Social

cognitive

determinants

of

ecstasy

use

to

target

in

evidence-based

interventions

a

meta-analytical

review

Aims

The

health

hazards

and

prevalence

of

ecstasy

use

have

been

documented

in

two

decades

of

research

but

no

review

reporting

on

potentially

modifiable

antecedents

of

use

is

available

The

aim

of

this

study

was

to

integrate

systematically

research

identifying

cognitive

correlates

of

ecstasy

use

Such

research

has

the

potential

to

identify

targets

for

evidence-based

interventions

designed

to

discourage

use

INTRODUCTION

Ecstasy

use

is

potentially

damaging

to

health

-LSB-

-RSB-

yet

prevalent

-LSB-

-RSB-

Legislative

changes

have

not

been

effective

in

discouraging

ecstasy

use

and

the

development

of

theory-based

behavioural

interventions

is

warranted

because

these

have

been

successful

in

generating

behaviour

change

in

other

areas

-LSB-

-RSB-

Behaviour

change

interventions

are

more

likely

to

be

effective

if

they

target

modifiable

antecedents

of

the

target

behaviour

For

example

if

expected

positive

outcomes

of

a

target

behaviour

differentiate

between

those

who

do

and

do

not

engage

in

that

behaviour

it

is

prudent

to

target

outcome

expectancies

in

behaviour

change

interventions

-LSB-

-RSB-

Which

potentially

modifiable

cognitive

antecedents

of

ecstasy

use

should

interventions

target

Unfortunately

although

ecstasy

was

synthesized

in

-LSB-

-RSB-

and

ecstasy

use

has

been

studied

for

years

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

there

is

no

systematic

review

of

this

research

identifying

potentially

modifiable

cognitive

antecedents

of

use

We

aimed

to

summarize

research

to

date

synthesizing

quantitatively

all

published

quantitative

studies

of

psychological

determinants

of

ecstasy

use

among

young

people

living

in

western

society

METHOD

The

search

strategy

comprised

three

iterative

steps

First

the

databases

PsycINFO

MedLine

and

ERIC

-LRB-

Education

Resources

Information

Center

-RRB-

were

searched

using

several

combinations

of

keywords

-LRB-

see

Appendix

I

-RRB-

The

results

of

the

final

query

were

then

scanned

manually

for

relevant

entries

by

examining

the

paper

titles

and

abstracts

-LRB-

see

Appendix

II

-RRB-

Four

inclusion

criteria

were

used

Firstly

a

study

should

investigate

the

target

population

of

young

recreative

ecstasy

users

in

western

society

as

factors

influencing

behaviour

can

be

population-specific

-LSB-

-RSB-

Secondly

a

study

should

measure

one

or

more

potentially

modifiable

determinants

of

ecstasy

use-related

behaviour

that

is

an

antecedent

that

could

be

influenced

potentially

by

health

promotional

interventions

-LRB-

excluding

for

example

demographics

personality

etc.

-RRB-

for

a

list

see

chapter

of

Bartholomew

et

al.

-LSB-

-RSB-

Thirdly

the

study

should

measure

either

actual

behaviour

or

intention

Finally

it

should

assess

quantitatively

the

relationship

between

determinants

and

behaviour

or

intention

Publications

selected

by

this

process

were

examined

in

detail

Second

reference

lists

of

these

papers

were

scanned

for

relevant

publications

-LRB-

the

ancestry

approach

-RRB-

Third

texts

citing

the

relevant

papers

were

located

using

the

Web

of

Science

database

-LRB-

the

descendancy

approach

-RRB-

Potentially

modifiable

determinants

were

extracted

from

the

studies

using

a

recommended

published

list

-LSB-

-RSB-

on

the

basis

of

which

two

authors

selected

determinants

from

each

paper

and

perfect

agreement

was

observed

Associations

between

determinants

and

behaviour

or

intention

across

studies

were

integrated

by

converting

all

statistics

to

the

correlation

coefficient

r

These

coefficients

were

then

transformed

to

Fisher

's

Z

and

weighed

by

sample

size

-LRB-

cf.

-LSB-

-RSB-

-RRB-

The

mean

Fisher

's

Z

was

then

transformed

back

to

the

correlation

coefficient

r

When

a

study

tested

a

variable

several

times

-LRB-

e.g.

frequency

of

use

and

intensity

of

use

-RRB-

the

resulting

effect

sizes

were

averaged

before

being

included

in

the

calculations

RESULTS

The

search

yielded

hits

from

which

publications

were

included

-LRB-

see

Appendix

II

-RRB-

Many

excluded

studies

had

a

biological

focus

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

examined

determinants

not

feasibly

changed

by

health

promoting

interventions

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

or

used

qualitative

methods

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

All

included

publications

studied

the

behaviour

using

ecstasy

-LRB-

or

the

intention

to

use

-RRB-

examined

determinants

of

trying

out

ecstasy

ceasing

use

changing

use

patterns

or

applying

harm

reduction

practices

Of

these

publications

six

were

discarded

after

thorough

examination

as

they

were

then

discovered

to

yield

no

quantitative

information

on

the

relevance

of

potentially

modifiable

determinants

of

behaviour

in

the

target

population

-LRB-

-LSB-

-RSB-

see

also

Appendix

II

-RRB-

Application

of

the

ancestry

approach

yielded

no

additional

publications

-LRB-

citations

scanned

-RRB-

but

the

descendancy

approach

yielded

one

additional

publication

-LRB-

of

unique

citing

publications

-LSB-

-RSB-

-RRB-

Of

the

final

set

of

publications

-LSB-

-RSB-

one

publication

described

two

studies

-LRB-

-LSB-

-RSB-

and

refer

to

studies

and

respectively

-RRB-

Table

describes

the

included

studies

listing

the

sample

details

the

extracted

potentially

modifiable

antecedents

and

how

they

were

measured

in

the

original

studies

Table

Quantitative

studies

into

the

determinants

of

using

ecstasy

and

measures

used

No

Sample

details

n

Age

Relevant

variables

I

R

-LSB-

-RSB-

UK

before

July

Polydrug

users

Negative

mood

function

scale

Social

function

scale

Negative

effects

Other

functions

-LRB-

functions

-RRB-

Extent

of

peer

use

Partner/best

friend

use

Intensity

of

use

-LSB-

-RSB-

UK

before

March

Alcohol

and

drug

users

Mood

function

scale

Social/contextual

function

scale

Negative

effects/events

scale

Extent

of

peer

use

Intention

Intensity

of

use

Frequency

of

use

-LSB-

-RSB-

UK

March

Students

Attitudes

Subjective

norms

Perceived

behavioural

control

Behavioural

beliefs

-LRB-

-RRB-

Normative

beliefs

-LRB-

-RRB-

Control

beliefs

-LRB-

-RRB-

Intention

to

use

ecstasy

-LSB-

-RSB-

UK

Club

members

Attitudes

Normative

influences

Perceived

behavioural

control

Self-efficacy

Behavioural

beliefs

Control

beliefs

Intention

Behaviour

-LRB-

longitudinal

-RRB-

-LSB-

-RSB-

Netherlands

Party

attendants

Negative

outcome

expectancies

Enhancement

outcome

expectancies

Euphoria

outcome

expectancies

Sex

outcome

expectancies

Dancing

outcome

expectancies

Insight

outcome

expectancies

Communication

outcome

expectancies

Whether

ecstasy

was

currently

used

-LSB-

-RSB-

UK

October

Students

Attitude

Injunctive

norms

Perceived

behavioural

control

Descriptive

norms

Moral

norm

Intention

Behaviour

-LRB-

longitudinal

-RRB-

-LSB-

-RSB-

UK

before

College

students

Frequency

of

past

use

Intentions

to

use

Normative

influence

-LRB-

friends

use

-RRB-

Beliefs

about

ecstasy

use

-LRB-

beliefs

-RRB-

-LSB-

-RSB-

UK

Attitude

Subjective

norm

Perceived

behavioural

control

over

obtaining

ecstasy

Perceived

behavioural

control

over

taking

ecstasy

Intention

Habit

Specific

attitudinal

beliefs

-LRB-

beliefs

-RRB-

Behaviour

-LRB-

longitudinal

-RRB-

-LSB-

-RSB-

the

Netherlands

Energy

motives

Euphoria

motives

Self-insight

motives

Sociability/flirtatiousness

motives

Sexiness

motives

Coping

motives

Conformism

motives

Perceived

positive

effects

Perceived

negative

effects

Perceived

friends

use

Frequency

of

ecstasy

use

-LSB-

-RSB-

UK

Attitude

Subjective

norm

Perceived

behavioural

control

over

obtaining

ecstasy

Perceived

behavioural

control

over

taking

ecstasy

Intention

Habit

-LSB-

-RSB-

USA

Club

rave

attendees

Risk

associated

with

using

ecstasy

once

or

twice

Risk

associated

with

using

ecstasy

regularly

Harmful

short-term

physical

effects

Harmful

long-term

physical

effects

Harmful

short-term

psychological

effects

Harmful

long-term

psychological

effects

Positive

physical

effects

Positive

psychological

effects

Ecstasy

use

within

the

past

months

No

number

in

reference

list

I

number

of

items

used

to

measure

variable

R

number

of

scale

points

on

response

scale

of

each

item

Longitudinal

design

All

studies

can

be

viewed

as

tests

of

two

theoretical

frameworks

which

are

applied

frequently

in

drug

use

research

-LSB-

-RSB-

Six

studies

-LSB-

b

-RSB-

tested

the

theory

of

planned

behaviour

-LRB-

TPB

-LSB-

-RSB-

-RRB-

The

TPB

proposes

that

the

most

proximal

cognitive

determinant

of

behaviour

is

intention

which

in

turn

is

predicted

by

attitude

-LRB-

i.e.

evaluation

of

probable

consequences

of

that

behaviour

-RRB-

subjective

norm

-LRB-

i.e.

perception

of

others

approval

of

the

behaviour

-RRB-

and

perceived

behavioural

control

-LRB-

PBC

i.e.

perception

of

control

based

on

perception

of

skills

and

external

obstacles/facilitators

-RRB-

Each

of

these

constructs

is

based

on

underlying

beliefs

Several

extensions

of

the

TPB

have

been

proposed

-LSB-

-RSB-

for

example

personal

norm

-LRB-

personal

moral

evaluation

of

the

behaviour

-RRB-

descriptive

norm

-LRB-

perception

of

others

performance

of

the

behaviour

-LSB-

-RSB-

-RRB-

habit

-LSB-

-RSB-

and

anticipated

regret

-LRB-

the

regret

one

experiences

when

prospectively

imagining

having

or

not

having

performed

a

behaviour

-LSB-

-RSB-

-RRB-

Five

studies

-LSB-

-RSB-

tested

expectancy

models

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

which

propose

that

behaviour

is

determined

by

expectations

people

have

of

the

behaviours

consequences

Two

studies

-LSB-

-RSB-

assessed

how

often

participants

used

ecstasy

for

particular

reasons

-LRB-

e.g.

in

the

past

year

how

often

have

you

used

ecstasy

to

help

you

to

let

go

of

inhibitions

-RRB-

implying

germane

expectations

-LRB-

such

as

taking

ecstasy

helps

me

let

go

of

inhibitions

-RRB-

Three

studies

-LSB-

-RSB-

used

more

traditional

measures

-LRB-

e.g.

I

have

experienced/would

expect

that

ecstasy

makes

it

easier

to

communicate

-RRB-

Note

that

these

expectations

are

viewed

as

underlying

beliefs

in

the

TPB

particularly

in

relation

to

the

structure

of

attitudes

-LSB-

-RSB-

In

both

the

TPB

and

outcome

expectancy

models

higher-level

constructs

such

as

attitudes

are

based

on

lower-level

beliefs

Most

studies

tested

models

involving

this

hierarchical

cognitive

structure

For

the

purposes

of

this

review

higher-level

constructs

are

referred

to

as

compound

constructs

and

lower-order

cognitions

as

expectancies

-LRB-

e.g.

beliefs

about

probable

consequences

of

ecstasy

use

-RRB-

Details

of

the

particular

theoretical

models

explored

in

the

original

studies

are

not

provided

here

Only

bivariate

analyses

were

synthesized

because

multivariate

analyses

were

incommensurable

over

studies

as

they

tested

different

models

-LSB-

In

order

to

resolve

this

by

conducting

uniform

regression

analyses

all

authors

were

asked

to

provide

matrices

of

covariance

However

due

to

lost

data

sets

missing

data

and

non-response

not

enough

data

could

be

retrieved

to

render

this

feasible

The

authors

are

grateful

to

M.

Conner

and

T.

ter

Bogt

who

did

supply

additional

data

-RSB-

It

is

worth

noting

the

less

that

in

the

two

TPB-based

studiesin

which

ecstasy

use

was

regressed

onto

compound

constructs

the

average

-LRB-

weighed

-RRB-

was

-LSB-

-RSB-

and

in

the

five

TPB-based

studies

in

which

intention

to

use

was

regressed

onto

compound

constructs

the

average

was

-LSB-

b

-RSB-

The

average

for

the

three

expectancy

studies

in

which

ecstasy

use

was

regressed

onto

expectancies

was

-LSB-

-RSB-

and

in

the

expectancy

study

where

intention

to

use

was

regressed

onto

expectancies

was

-LSB-

-RSB-

In

three

prospective

studies

ecstasy

use

was

found

to

be

related

strongly

to

prior

intention

to

use

with

an

average

-LRB-

weighed

-RRB-

r

of

-LSB-

-RSB-

Table

shows

the

strength

of

association

between

predictor

variables

and

measures

of

ecstasy

use

and

intention

to

use

The

strongest

predictor

of

intention

and

use

was

the

TPB-specified

attitude

measure

Attitudes

are

thought

to

be

based

on

more

specific

expectancies

-LSB-

-RSB-

and

these

are

shown

separately

in

Table

grouped

into

positive

and

negative

expectancies

In

addition

to

these

perceived

advantages

and

disadvantages

of

ecstasy

use

normative

measures

have

been

used

especially

subjective

and

descriptive

norms

as

well

as

perceived

behavioural

control

over

ecstasy

use

Variables

proposed

as

extensions

to

the

TPB

have

been

categorized

as

miscellaneous

Table

Effect

sizes

of

predictors

of

ecstasy

use

and

intention

to

use

Association

with

behaviour

Association

with

intention

Variable

type

Compound

or

expectancy

k

r

k

r

Attitude

Attitude

-LSB-

C

-RSB-

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Positive

expectancies

Social

function

-LSB-

C

-RSB-

-LRB-

M

-RRB-

Produces

a

positive

mood

state

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Mood

function

-LSB-

C

-RSB-

-LRB-

S

-RRB-

-LRB-

L

-RRB-

Helps

lose

weight

Enhances

sex

-LRB-

S

-RRB-

Helps

stay

awake

Helps

keep

fit

-LRB-

S

-RRB-

-LRB-

S

-RRB-

Enhances

insight/openness

-LRB-

S

-RRB-

Helps

to

relax/helps

coping

Produces

excitement

-LRB-

M

-RRB-

Produces

intoxication

-LRB-

S

-RRB-

Eases

after-effects

-LRB-

S

-RRB-

Improves

other

drugs

effects

-LRB-

S

-RRB-

Is

conforming

to

peers

Helps

work

Negative

expectancies

Short-term

negative

effects

-LSB-

C

-RSB-

-LRB-

L

-RRB-

Produces

mood

swings

-LRB-

M

-RRB-

-LRB-

M

-RRB-

Leads

on

to

more

frequent

use

-LRB-

M

-RRB-

-LRB-

L

-RRB-

Produces

mental

side-effects

-LRB-

M

-RRB-

-LRB-

L

-RRB-

Leads

on

to

worse

drugs

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Produces

physical

side-effects

-LRB-

S

-RRB-

-LRB-

L

-RRB-

Makes

one

unhealthy

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Produces

depression

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Produces

lethargy

-LRB-

S

-RRB-

Produces

addiction

-LRB-

M

-RRB-

-LRB-

S

-RRB-

Leads

to

death

-LRB-

M

-RRB-

-LRB-

M

-RRB-

Produces

paranoia

-LRB-

M

-RRB-

-LRB-

M

-RRB-

Makes

one

feel

run

down

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Subjective

injunctive

norm

Subjective

norms

-LRB-

approval

-RRB-

-LSB-

C

-RSB-

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Best

friends

approval

-LRB-

M

-RRB-

-LRB-

M

-RRB-

Partners

approval

-LRB-

S

-RRB-

-LRB-

M

-RRB-

Parents

approval

-LRB-

S

-RRB-

Health

experts

approval

Other

ecstasy

users

approval

Subjective

descriptive

norm

Subjective

norms

-LRB-

descriptive

-RRB-

-LSB-

C

-RSB-

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Perceived

peer

use

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Perceived

use

in

close

relatives

-LRB-

S

-RRB-

Perceived

best

friend/partner

use

-LRB-

L

-RRB-

Perceived

behavioural

control

PBC

-LSB-

C

-RSB-

-LRB-

M

-RRB-

-LRB-

L

-RRB-

PBC

-LRB-

over

obtaining

ecstasy

-RRB-

-LRB-

M

-RRB-

-LRB-

M

-RRB-

PBC

-LRB-

over

taking

ecstasy

-RRB-

Being

with

friends

who

use

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Going

out

dancing

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Being

offered

ecstasy

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Ecstasy

being

available

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Cheap

ecstasy

-LRB-

M

-RRB-

-LRB-

L

-RRB-

Having

alcohol

-LRB-

S

-RRB-

PBC

-LRB-

over

not

taking

ecstasy

-RRB-

Needing

to

lose

weight

Needing

to

exercise

Miscellaneous

Habit

-LSB-

C

-RSB-

-LRB-

L

-RRB-

-LRB-

L

-RRB-

Moral

norm

-LSB-

C

-RSB-

-LRB-

M

-RRB-

-LRB-

M

-RRB-

Denial

of

negative

consequences

-LRB-

S

-RRB-

-LRB-

S

-RRB-

Anticipated

regret

-LRB-

S

-RRB-

-LRB-

S

-RRB-

-LSB-

C

-RSB-

compound

construct

k

no

of

samples

r

weighed

average

correlation

-LRB-

S

-RRB-

small

-LRB-

M

-RRB-

medium

-LRB-

L

-RRB-

large

effect

size

magnitude

according

to

Cohen

-LSB-

-RSB-

PBC

perceived

behavioural

control

Table

is

based

on

the

Pearson

correlations

reported

in

five

studies

-LSB-

-RSB-

and

correlation

matrices

received

from

the

authors

of

two

publications

-LSB-

-RSB-

One

study

-LSB-

-RSB-

reported

t-values

which

were

converted

into

effect

size

correlations

using

r

-LSB-

-LRB-

df

-RRB-

-RSB-

The

results

from

two

studies

-LSB-

-RSB-

could

not

be

converted

and

will

be

provided

later

Only

associations

found

in

at

least

two

samples

of

magnitudes

corresponding

to

a

medium

-LRB-

Cohen

's

d

-LSB-

-RSB-

r

-RRB-

or

large

effect

size

-LRB-

d

and

r

-RRB-

are

considered

All

significant

associations

were

in

the

expected

direction

and

some

large

effect

sizes

were

observed

suggesting

that

both

the

theory

of

planned

behaviour

and

the

expectancy

approach

can

help

to

explain

ecstasy

use

and

intentions

to

use

In

the

TPB

studies

intention

and

behaviour

are

associated

most

strongly

with

TPB

's

attitude

with

a

large

effect

size

-LRB-

r

with

behaviour

r

with

intention

-RRB-

Specifically

this

compound

construct

appears

to

be

associated

mainly

with

positive

outcomes

regarding

mood

control

and

social

facilitation

and

negative

expectations

regarding

short-term

negative

effects

escalating

use

and

physical

and

mental

side

effects

Normative

influences

are

also

important

covariates

of

use

and

intention

to

use

with

stronger

associations

observed

for

descriptive

-LRB-

r

with

behaviour

r

with

intention

-RRB-

than

injunctive

norms

-LRB-

r

with

behaviour

r

with

intention

-RRB-

The

strongest

effect

sizes

for

expectancies

underpinning

these

compound

constructs

were

observed

for

perceived

ecstasy

use

by

peers

and

approval

of

use

by

one

's

best

friend

and

partner

The

results

also

indicate

that

whether

parents

health

experts

and

other

ecstasy

users

approve

is

inconsequential

Perceived

behavioural

control

was

related

to

use

with

a

medium

-LRB-

near

large

-RRB-

effect

size

-LRB-

r

-RRB-

and

also

related

strongly

to

intention

-LRB-

r

-RRB-

Underlying

beliefs

showed

a

medium

effect

regarding

control

over

obtaining

ecstasy

and

large

effects

of

control

in

relation

to

being

with

friends

who

use

going

out

dancing

being

offered

ecstasy

and

ecstasy

being

available

Two

proposed

extensions

to

TPB

appear

relevant

habit

with

a

large

effect

size

-LRB-

r

with

behaviour

r

with

intention

-RRB-

and

moral

norm

with

a

medium

effect

size

-LRB-

r

with

behaviour

r

with

intention

-RRB-

Two

studies

reported

results

using

statistics

that

could

not

be

transformed

to

an

effect

size

measure

One

study

-LSB-

-RSB-

conducted

a

polynomial

logistic

regression

predicting

user

group

-LRB-

six

levels

rejectors

at-risk

non-users

ex-users

and

light

moderate

and

heavy

users

for

details

see

-LSB-

-RSB-

-RRB-

testing

whether

a

number

of

variables

contributed

significantly

to

model

fit

when

predicting

user

group

Another

study

-LSB-

-RSB-

conducted

t-tests

on

beliefs

-LRB-

also

predicting

user

group

with

two

levels

non-user

and

user

-RRB-

but

did

not

report

t-values

exact

P-values

or

variance

information

The

variables

tested

in

these

studies

are

shown

in

Table

Effect

sizes

were

estimated

-LRB-

conservatively

-RRB-

on

the

basis

of

sample

size

and

significance

Table

Significant

and

non-significant

predictors

of

user

group

-LRB-

user

group

had

six

levels

in

study

-LSB-

-RSB-

and

two

levels

in

study

-LSB-

-RSB-

-RRB-

Variable

Study

Significance

Association

Effect

size

Perceived

use

by

friends

-LSB-

-RSB-

Positive

M

Anticipated

regret

-LRB-

use

would

induce

guilt

-RRB-

-LSB-

-RSB-

Negative

M

Is

hard

to

resist

-LSB-

-RSB-

Positive

M

Moral

norm

-LRB-

ecstasy

use

is

immoral

-RRB-

-LSB-

-RSB-

Negative

S

Perceived

availability

of

ecstasy

-LSB-

-RSB-

Positive

S

Is

bad

for

one

's

physical

health

-LSB-

-RSB-

Is

bad

for

one

's

mental

health

-LSB-

-RSB-

Subjective

norm

-LRB-

approval

-RRB-

-LSB-

-RSB-

Harmful

long-term

physical

effects

-LSB-

-RSB-

Negative

M

Risk

associated

with

using

regularly

-LSB-

-RSB-

Negative

M

Risk

association

with

using

once

or

twice

-LSB-

-RSB-

Negative

M

Harmful

long-term

psychological

effects

-LSB-

-RSB-

Negative

M

Harmful

short-term

physical

effects

-LSB-

-RSB-

Harmful

short-term

psychological

effects

-LSB-

-RSB-

Positive

physical

effects

-LSB-

-RSB-

Positive

psychological

effects

-LSB-

-RSB-

S

small

M

medium

effect

size

magnitude

according

to

Cohen

-LSB-

-RSB-

These

additional

results

confirm

the

relevance

of

descriptive

norm

negative

expectancies

-LRB-

particularly

long-term

effects

-RRB-

and

perceived

control

and

add

anticipated

regret

with

at

least

a

medium

effect

size

to

the

list

DISCUSSION

Synthesis

of

the

included

studies

shows

the

main

predictors

of

intention

to

use

and

actual

ecstasy

use

to

be

attitude

-LRB-

specifically

positive

outcomes

regarding

mood

control

and

social

facilitation

and

negative

outcomes

regarding

escalating

use

and

physical

and

mental

side-effects

-RRB-

subjective

and

descriptive

norms

regarding

one

's

friends

partner

and

peers

perceived

control

regarding

obtaining

ecstasy

and

control

in

relation

to

being

with

friends

who

use

going

out

dancing

being

offered

ecstasy

and

ecstasy

being

available

and

habit

moral

norm

and

anticipated

regret

In

addition

to

lending

support

to

both

the

TPB

and

expectancy

models

these

findings

show

that

some

expectancies

underlying

attitude

are

irrelevant

-LRB-

e.g.

ecstasy

enhances

sex

-RRB-

as

are

norms

relating

to

some

social

referents

-LRB-

e.g.

parents

-RRB-

and

perceived

control

regarding

some

ecstasy-related

behaviours

-LRB-

e.g.

taking

ecstasy

-RRB-

As

it

is

now

clear

which

determinants

best

predict

intention

to

use

and

ecstasy

use

according

to

the

research

so

far

these

determinants

seem

advisable

intervention

targets

However

not

all

determinants

are

equally

easy

to

modify

As

attitude

encompasses

several

specific

expectancies

it

may

be

easier

to

target

these

more

concrete

expectancies

than

the

abstract

attitude

construct

Also

not

all

expectancies

are

influenced

equally

easily

Because

most

users

have

experienced

positive

mood

shifts

it

may

be

difficult

to

develop

persuasive

messages

that

undermine

this

expectancy

among

users

-LSB-

-RSB-

Negative

variables

are

also

associated

strongly

and

changed

more

easily

However

simply

presenting

information

about

negative

outcomes

-LRB-

fear

appeals

-RRB-

has

been

shown

not

to

work

or

even

work

inversely

unless

a

number

of

critical

conditions

are

met

such

as

efficacy

enhancement

-LRB-

see

-LSB-

-RSB-

also

see

-LSB-

-RSB-

-RRB-

Similarly

it

may

be

difficult

to

change

a

subjective

norm

if

it

reflects

reality

As

ecstasy

use

is

social

-LSB-

-RSB-

and

most

users

take

ecstasy

at

a

dance

event

-LSB-

-RSB-

where

ecstasy

use

is

high

-LRB-

in

the

Netherlands

about

two-thirds

of

the

visitors

use

ecstasy

-LSB-

-RSB-

-RRB-

it

might

be

hard

to

reduce

descriptive

norms

especially

if

participants

friends

use

ecstasy

Similarly

it

may

be

challenging

to

establish

a

disapproving

norm

-LRB-

see

-LSB-

-RSB-

-RRB-

Similarly

it

may

be

difficult

to

reduce

perceived

control

over

obtaining

ecstasy

among

users

as

they

probably

have

repeatedly

performed

this

behaviour

successfully

However

the

large

effects

of

specific

control

beliefs

suggest

that

users

who

wish

to

stop

may

well

be

aided

by

adopting

a

stimulus

control

strategy

avoiding

the

social

contexts

of

use

In

addition

enhancing

refusal

skills

would

influence

perceived

behavioural

control

while

also

diminishing

the

effect

of

undesirable

subjective

norms

-LRB-

by

decreasing

users

motivation

to

comply

see

-LSB-

-RSB-

-RRB-

Thus

among

those

with

intentions

not

to

use

refusal

skills

training

and

stimulus

control

are

recommended

-LSB-

-RSB-

Finally

habit

and

moral

norm

are

useful

predictors

but

may

be

difficult

to

change

-LRB-

-LSB-

-RSB-

but

also

see

-LSB-

-RSB-

-RRB-

Although

anticipated

regret

has

a

smaller

association

with

use

and

intention

to

use

it

can

be

changed

more

easily

-LRB-

e.g.

-LSB-

-RSB-

-RRB-

A

list

of

methods

and

strategies

to

change

these

determinants

and

the

theoretical

parameters

prerequisite

to

success

is

provided

in

chapter

of

Bartholemew

et

al.

-LSB-

-RSB-

This

review

is

limited

mainly

by

the

fact

that

only

bivariate

associations

could

be

synthesized

and

by

two

consequences

of

the

paucity

of

research

into

ecstasy

use

thus

far

First

the

small

number

of

studies

into

determinants

of

ecstasy

use

limit

the

robustness

of

the

current

findings

Second

many

theories

and

models

have

not

yet

been

studied

and

are

therefore

not

included

in

this

review

Only

social

cognitive

theories

have

been

tested

no

studies

have

investigated

for

example

the

predictive

value

of

implicit

cognitions

However

recent

research

implies

that

implicit

processes

may

be

changeable

-LSB-

-RSB-

Moreover

within

social

cognitive

research

recently

developed

constructs

such

as

consideration

of

future

consequences

-LSB-

-RSB-

have

not

yet

been

applied

to

ecstasy

use

but

may

aid

in

intervention

development

Regarding

the

theories

that

have

been

studied

in

order

to

gain

a

more

comprehensive

understanding

of

motives

for

ecstasy

use

future

research

should

combine

the

two

theoretical

perspectives

studied

thus

far

so

that

relative

overlap

can

be

determined

It

would

be

interesting

to

see

whether

and

to

what

degree

particular

expectancies

account

for

the

predictive

utility

of

the

TPB

attitude

measures

Also

the

list

of

expectancies

that

has

been

studied

so

far

may

omit

a

number

of

consequences

-LRB-

such

as

suicide

Tuesday

a

term

for

a

period

following

use

when

low

serotonin

levels

can

induce

depressive

feelings

-RRB-

Another

important

gap

in

the

literature

concerns

behaviours

other

than

using

ecstasy

Not

only

can

the

determinants

of

trying

ecstasy

out

starting

use

ceasing

use

and

maintaining

cessation

differ

from

the

determinants

of

using

ecstasy

-LSB-

-RSB-

little

is

known

about

the

determinants

of

harm

reduction

practices

such

as

having

one

's

ecstasy

tested

by

a

test

service

ensuring

sufficient

hydration

and

maintaining

a

low

body

temperature

-LRB-

although

studies

such

as

-LSB-

-RSB-

are

a

step

in

the

right

direction

-RRB-

Intervening

to

promote

these

behaviours

could

prove

to

be

more

beneficial

to

the

health

of

party

visitors

given

the

difficulty

of

intervening

on

most

variables

determining

ecstasy

use

In

conclusion

this

review

suggests

that

there

is

sufficient

evidence

to

guide

intervention

development

so

that

evidence-based

practice

is

established

These

interventions

could

then

be

evaluated

to

test

the

utility

of

particular

theoretical

frameworks

The

priorities

for

interventions

should

be

negative

expectancies

perceived

behavioural

control

and

anticipated

regret

Tailored

interventions

can

offer

refusal

skills

training

and

strategies

to

avoid

risky

situations

to

participants

not

intending

to

use

ecstasy

Appendix

I

Search

terms

used

in

PsycINFO

-LRB-

equivalent

terms

used

in

corresponding

fields

in

MedLine

and

ERIC

-RRB-

-LSB-

query

in

words

as

corresponding

to

concepts

column

in

brackets

-RSB-

-LRB-

English

-RRB-

or

-LRB-

Dutch

-RRB-

type

-LRB-

journal

-RRB-

or

-LRB-

peer-reviewed-journal

-RRB-

Publication

date

-LRB-

clubdrug

-RRB-

or

-LRB-

club

near

drug

-RRB-

or

-LRB-

dance

near

drug

-RRB-

or

-LRB-

dancedrug

-RRB-

or

-LRB-

party

near

drug

-RRB-

or

-LRB-

partydrug

-RRB-

or

-LRB-

xtc

-RRB-

or

-LRB-

mdma

-RRB-

or

-LRB-

methylenedioxymethamphetamine

-RRB-

or

-LRB-

-RRB-

or

-LRB-

ecstasy

-RRB-

Title

abstract

-LRB-

theor

-RRB-

or

-LRB-

attitud

-RRB-

or

-LRB-

motivat

near

functio

-RRB-

or

-LRB-

mode

-RRB-

or

-LRB-

norm

-RRB-

or

-LRB-

perceived

near

control

-RRB-

or

-LRB-

pbc

-RRB-

or

-LRB-

social

cognitive

-RRB-

or

-LRB-

self

adj

efficacy

-RRB-

or

-LRB-

stages

near

change

-RRB-

or

-LRB-

perceived

adj

-LRB-

harm

or

risk

or

functions

-RRB-

-RRB-

or

-LRB-

functional

-RRB-

or

-LRB-

outcome

adj

-LRB-

expectancies

or

expectations

-RRB-

-RRB-

or

-LRB-

sct

-RRB-

or

-LRB-

tpb

-RRB-

or

-LRB-

patter

-RRB-

or

-LRB-

psychosoc

-RRB-

or

-LRB-

health

adj

belief

adj

model

-RRB-

or

-LRB-

hbm

-RRB-

Title

abstract

-LRB-

determin

-RRB-

or

-LRB-

facto

-RRB-

or

-LRB-

variabl

-RRB-

or

-LRB-

parameter

-RRB-

or

-LRB-

reason

-RRB-

or

-LRB-

caus

-RRB-

or

-LRB-

motiv

-RRB-

or

-LRB-

incentive

-RRB-

or

-LRB-

correlat

-RRB-

or

-LRB-

antecedent

-RRB-

or

-LRB-

character

-RRB-

Title

abstract

-LRB-

start

-RRB-

or

-LRB-

commenc

-RRB-

or

-LRB-

originat

-RRB-

or

-LRB-

onset

-RRB-

or

-LRB-

initiat

-RRB-

or

-LRB-

instigat

-RRB-

or

-LRB-

-LRB-

use

-RRB-

not

-LRB-

user

-RRB-

-RRB-

or

-LRB-

using

-RRB-

or

-LRB-

usage

-RRB-

or

-LRB-

establish

-RRB-

Title

abstract

-LRB-

maint

-RRB-

or

-LRB-

sustain

-RRB-

or

-LRB-

continu

-RRB-

or

-LRB-

uphold

-RRB-

or

-LRB-

persist

-RRB-

or

-LRB-

further

-RRB-

or

-LRB-

prolong

-RRB-

Title

abstract

-LRB-

end

-RRB-

or

-LRB-

stop

-RRB-

or

-LRB-

discontinu

-RRB-

or

-LRB-

terminat

-RRB-

or

-LRB-

ceas

-RRB-

or

-LRB-

cessat

-RRB-

or

-LRB-

abstain

-RRB-

or

-LRB-

abstin

-RRB-

or

-LRB-

quit

-RRB-

or

-LRB-

remiss

-RRB-

or

-LRB-

resolut

-RRB-

or

-LRB-

recover

-RRB-

Title

abstract

reduction

-LRB-

harm

or

risk

or

damage

or

casualt

-RRB-

and

-LRB-

reduc

or

manag

or

limit

or

minimi

-RRB-

Title

abstract

-LRB-

-LRB-

treatment

not

-LRB-

not

in

treatment

or

non-treatment

or

non

treatment

or

no

treatment

-RRB-

-RRB-

or

rat

or

rats

or

mouse

or

mice

or

animal

or

monkey

or

pigeon

or

spectro

or

cardio

or

seroton

or

dopamin

or

neurotransm

or

receptor

or

psychiatr

or

psychopath

or

cell

or

diagnos

-RRB-

and

and

-LSB-

Language

and

Publication

Type

and

Publication

Date

-RSB-

or

or

or

-LSB-

Initiation

or

Maintenance

or

Cessation

or

Harm

reduction

-RSB-

near

-LSB-

Determinants

near

Behaviour

-RSB-

query

and

near

-LRB-

or

-RRB-

not

-LSB-

Inclusion

and

Ecstasy

near

-LRB-

Theoretical

or

Empirical

-RRB-

not

Excluded

-RSB-

When

executed

the

query

consisted

of

one

command

therefore

the

use

of

the

near

operator

was

valid

here

Appendix

II

Search

procedure

number

of

resulting

hits

and

results

of

each

step

Step

Activity

Number

of

resulting

publications

Input

of

query

at

August

in

PsycINFO

-LRB-

-RRB-

MedLine

-LRB-

-RRB-

and

ERIC

-LRB-

-RRB-

Removal

of

duplicate

records

-LRB-

-RRB-

Removal

of

records

about

publications

that

-LRB-

entries

were

removed

in

this

order

-RRB-

studied

biological

variables

-LRB-

e.g.

sequelae

of

ecstasy

use

-RRB-

did

not

study

ecstasy

use

or

a

related

behaviour

-LRB-

such

as

trying

out

ecstasy

ceasing

use

changing

use

patterns

or

applying

harm

reduction

practices

-RRB-

studied

variables

that

can

not

be

changed

using

a

health

promotion

intervention

-LRB-

e.g.

sex

ethnicity

or

religion

-RRB-

studied

ecstasy

use

as

an

independent

variable

in

a

multivariate

or

longitudinal

analysis

-LRB-

-RRB-

did

not

employ

quantitative

methods

-LRB-

e.g.

qualitative

studies

-RRB-

did

not

study

behaviour

or

cognitions

-LRB-

-RRB-

studied

a

non-normal

subpopulation

or

gathering

data

from

samples

inseparably

encompassing

these

subpopulations

-LRB-

e.g.

dependent

participants

patients

or

delinquents

-RRB-

studying

generic

drug

categories

-LRB-

e.g.

hard

drugs

-RRB-

or

not

explicitly

stating

which

drugs

were

studied

-LRB-

-RRB-

were

not

published

in

a

peer-reviewed

journal

-LRB-

-RRB-

inclusion

of

these

subpopulations

would

restrict

generalization

of

the

results

to

the

target

population

of

the

current

study

-LRB-

i.e.

the

average

adolescent

see

-LSB-

-RSB-

-RRB-

this

demand

of

drug

specificity

is

necessary

because

previous

research

has

shown

that

beliefs

about

drugs

can

vary

between

different

drugs

-LSB-

-RSB-

rendering

aggregation

questionable

O O B O B O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O B O O O O B O O O O B O O O O B O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O B O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B O O B O O O O O O O O O O O O O B O O B O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O

determinants
drugs
ecstasy
expectancies
review
theory of planned behaviour


Applicability

of

current

staging/categorization

of

α-synuclein

pathology

and

their

clinical

relevance

In

Parkinson

's

disease

-LRB-

PD

-RRB-

and

dementia

with

Lewy

bodies

-LRB-

DLB

-RRB-

α-synuclein

-LRB-

αS

-RRB-

pathology

is

seen

that

displays

a

predictable

topographic

distribution

There

are

two

staging/categorization

systems

i.e.

Braak

's

and

McKeith

's

currently

in

use

for

the

assessment

of

αS

pathology

The

aim

of

these

diagnostic

strategies

in

pathology

is

in

addition

to

assess

the

stage/severity

of

pathology

to

assess

the

probabilities

of

the

related

clinical

symptomatology

i.e.

dementia

and

extrapyramidal

symptoms

-LRB-

EPS

-RRB-

Herein

we

assessed

the

applicability

of

these

two

staging/categorization

systems

and

the

frequency

of

dementia

and

EPS

in

a

cohort

of

αS-positive-subjects

These

subject

were

selected

from

a

large

autopsy

sample

-LRB-

n

-RRB-

irrespective

of

the

clinical

presentation

based

on

the

detection

of

αS-immunoreactivity

-LRB-

IR

-RRB-

in

one

of

the

most

vulnerable

nuclei

in

the

dorsal

motor

nucleus

of

vagus

substantia

nigra

and

basal

forebrain

The

frequency

of

αS-IR

lesions

in

this

large

cohort

was

-LRB-

out

of

-RRB-

If

applicable

each

of

the

subjects

with

all

required

material

available

was

assigned

a

neuropathological

stage/category

of

PD/DLB

and

finally

the

neuropathological

data

was

analyzed

in

relation

to

dementia

and

EPS

of

subjects

showed

a

distribution

pattern

of

αS-IR

that

was

compatible

with

the

current

staging/categorization

systems

Around

of

subjects

with

widespread

αS

pathology

-LRB-

Braak

's

PD

stages

-RRB-

lacked

clinical

signs

of

dementia

or

EPS

Similarly

in

respect

to

those

subjects

that

fulfilled

the

McKeith

criteria

for

diffuse

neocortical

category

and

displaying

only

mild

concomitant

Alzheimer

's

disease-related

pathology

only

were

demented

and

displayed

EPS

It

is

noteworthy

that

some

subjects

-LRB-

-RRB-

deviated

from

the

suggested

caudo-rostral

propagation

suggesting

alternative

routes

of

progression

perhaps

due

to

concomitant

diseases

and

genetic

predisposition

In

conclusion

our

results

do

indeed

confirm

that

current

staging/categorization

systems

can

readily

be

applied

to

most

of

the

subjects

with

αS

pathology

However

finding

that

around

half

of

the

subjects

with

abundant

αS

pathology

remain

neurologically

intact

is

intriguing

and

raises

the

question

whether

we

do

assess

the

actual

disease

process

Introduction

There

are

two

staging/categorization

systems

commonly

in

use

for

the

assessment

of

the

progressive

regional

distribution

of

the

pathology

seen

in

Parkinson

's

disease

-LRB-

PD

-RRB-

and

dementia

with

Lewy

bodies

-LRB-

DLB

-RRB-

Both

of

these

staging/categorization

systems

are

based

on

the

assessment

of

misfolded

α-synuclein

-LRB-

αS

-RRB-

protein

within

selectively

vulnerable

neuronal

populations

which

is

considered

to

be

either

directly

responsible

or

at

least

intimately

linked

to

the

neuronal

dysfunction

seen

in

PD

and

DLB

In

this

respect

αS-immunoreactive

-LRB-

IR

-RRB-

inclusions

in

the

brainstem

have

been

claimed

to

be

responsible

for

the

extrapyramidal

symptoms

-LRB-

EPS

-RRB-

whereas

dementia

has

been

attributed

to

the

limbic

and

neocortical

spread

of

these

lesions

Thus

PD

and

DLB

are

thought

to

form

a

clinico-pathologic

continuum

wherein

the

clinical

manifestation

of

EPS

and/or

dementia

depends

on

the

anatomical

distribution

and

the

load

of

αS

pathology

-LSB-

-RSB-

In

Braak

and

colleagues

reported

that

the

αS

pathology

begins

in

clearly

defined

induction

sites

and

advances

not

in

a

random

but

in

a

predictable

sequence

with

increasing

severity

throughout

the

brain

-LSB-

-RSB-

Based

on

the

analysis

of

the

regional

distribution

of

αS-IR

inclusions

in

a

cohort

including

both

neurologically

unimpaired

subjects

and

patients

with

PD

a

staging

system

was

devised

whereby

αS

pathology

was

divided

into

six

successive

stages

In

the

central

nervous

system

the

proposed

sequence

begins

in

the

dorsal

motor

nucleus

of

vagus

-LRB-

dmV

-RRB-

and

then

proceeds

with

an

upward

progression

via

locus

coeruleus

-LRB-

LC

-RRB-

-LRB-

stage

-RRB-

to

the

substantia

nigra

-LRB-

SN

-RRB-

-LRB-

stage

-RRB-

and

then

to

the

basal

foreberain

-LRB-

BFB

-RRB-

and

transentorhinal

region

-LRB-

stage

-RRB-

until

it

finally

reaches

the

neocortex

-LRB-

stages

-RRB-

Already

in

the

consortium

on

DLB

international

workshop

proposed

their

consensus

guidelines

for

the

clinical

and

pathologic

diagnosis

of

DLB

-LSB-

-RSB-

that

later

in

were

somewhat

revised

-LSB-

-RSB-

These

consensus

criteria

of

DLB

subdivide

subjects

into

three

different

neuropathological

categories

brainstem

predominant

limbic/transitional

and

diffuse

neocortical

depending

on

the

anatomical

distribution

of

the

αS-IR

structures

-LSB-

-RSB-

These

criteria

also

include

the

semiquantitative

grading

of

lesion

density

although

the

pattern

of

regional

involvement

has

been

assumed

to

be

more

important

than

the

actual

count

of

inclusions

It

is

noteworthy

that

in

the

revised

recommendations

by

McKeith

et

al

from

-LSB-

-RSB-

it

is

emphasized

that

the

concomitant

pathologies

should

be

taken

into

account

when

assessing

the

causative

relationships

between

pathologies

and

symptoms

Thus

the

most

common

pathology

seen

in

aged

demented

individuals

i.e.

Alzheimer

's

disease

-LRB-

AD

-RRB-

related

pathology

should

be

evaluated

while

assessing

the

likelihood

of

causation

i.e.

that

the

αS

pathology

is

associated

with

a

DLB

clinical

syndrome

Herein

we

assess

the

applicability

of

these

two

current

staging/categorization

systems

of

synucleinopathies

in

a

large

autopsy

material

collected

not

on

the

basis

of

clinical

presentation

but

by

αS

immunoreactivity

in

some

of

the

most

vulnerable

nuclei

dmV

SN

and

BFB

Thus

the

selection

of

material

was

entirely

based

on

the

presence

of

αS

pathology

irrespective

of

clinical

phenotype

All

subjects

if

applicable

were

assigned

a

stage

following

in

detail

Braak

staging

recommendations

and

a

McKeith

neuropathological

category

following

in

detail

recommendations

by

the

consortium

on

DLB

international

workshop

-LSB-

-RSB-

The

frequency

of

dementia

and

EPS

was

assessed

in

each

stage

and

the

likelihood

that

dementia

was

due

to

AD-related

pathology

or

αS

pathology

was

also

examined

Materials

and

methods

Selection

of

subjects

and

the

clinical

assessment

The

flowchart

delineates

the

logistics

of

this

study

-LRB-

Fig.

-RRB-

A

total

of

elderly

individuals

-LRB-

age

at

death

years

-RRB-

that

had

undergone

an

autopsy

together

with

an

examination

of

the

brain

during

the

years

in

the

Kuopio

University

Hospital

were

included

in

this

study

From

this

large

autopsy

sample

we

selected

-LRB-

-RRB-

subjects

that

displayed

αS-IR

structures

in

the

SN

and/or

BFB

nuclei

nucleus

basalis

of

Meynert

-LRB-

nbM

-RRB-

and

amygdaloid

complex

-LRB-

AC

-RRB-

Screening

of

dmV

was

also

carried

out

in

and

revealed

that

in

subjects

out

of

-LRB-

-RRB-

αS-IR-structures

were

restricted

to

the

lower

brain

stem

nuclei

-LRB-

dmV

and/or

LC

-RRB-

-LSB-

-RSB-

Five

subjects

were

excluded

from

the

analysis

because

they

had

received

a

pathological

diagnosis

of

MSA

Seventeen

subjects

were

excluded

due

to

lack

of

clinical

information

or

inadequate

amount

of

brain

material

required

for

the

classification

as

recommended

by

Mc

Keith

and

Braak

-LSB-

-RSB-

and

thus

ultimately

this

study

examined

subjects

Fig.

flowchart

delineating

the

logistics

of

this

study

a

The

αS-immunoreactive

inclusions

were

screened

in

substantia

nigra

amygdaloid

complex

and

dorsal

motor

nucleus

of

vagus

b

Schematic

presentation

of

both

Braak

staging

and

McKeith

categorization

-LSB-

-RSB-

and

c

schematic

presentation

of

assessment

of

likelihood

that

αS-immunoreactive

inclusion

are

associated

with

dementia

with

Lewy

bodies

-LSB-

-RSB-

The

diagnosis

of

dementia

was

based

on

the

DSM-III

criteria

and

the

criteria

of

the

National

Institute

of

Neurological

and

Communicative

Disorders

and

Stroke-Alzheimer

's

Disease

and

Related

Disorders

Association

-LRB-

NINCDS-ADRDA

-RRB-

-LSB-

-RSB-

The

diagnosis

of

PD

followed

the

criteria

established

by

the

United

Kingdom

Parkinson

's

Disease

Society

Brain

Bank

whereby

PD

was

considered

present

if

the

patient

had

at

least

two

of

the

four

cardinal

symptoms

-LRB-

resting

tremor

rigidity

hypokinesia

and

postural

instability

-RRB-

and

exhibited

a

positive

response

to

levodopa

-LSB-

-RSB-

The

initial

screening

for

both

dementia

and

EPS

had

taken

place

in

a

primary

health

care

centre

With

respects

to

dementia

all

patients

scoring

or

less

in

minimental

State

Examination

-LRB-

MMSE

-RRB-

had

been

referred

to

a

neurologist

for

further

evaluation

and

all

patients

scoring

in

MMSE

but

displaying

signs

of

memory

impairment

had

been

referred

to

a

CERAD

test

Consequently

many

subjects

had

been

examined

by

a

neurologist

and

all

had

at

least

visited

a

general

physician

-LRB-

within

a

maximum

of

year

before

death

-RRB-

It

is

noteworthy

that

many

of

the

subjects

included

in

this

study

had

been

under

continuous

clinical

follow-up

due

to

some

chronic

disease

Admittedly

some

subjects

may

have

developed

subtle

extrapyramidal

signs

or

mild

cognitive

impairment

between

the

last

clinical

examination

and

death

but

it

is

most

unlikely

that

the

presence

of

moderate

or

full-blown

parkinsonian

syndrome/dementia

would

have

been

overlooked

Neuropathological

assessment

According

to

the

dissection

protocol

used

in

the

Kuopio

University

Hospital

the

brains

were

weighed

evaluated

for

grossly

detectable

lesions

and

vessel

abnormalities

perfused

with

and

immersed

in

buffered

formalin

for

at

least

one

week

and

cut

in

coronal

slices

of

cm

thickness

Brain

specimens

were

embedded

in

paraffin

and

cut

into

μm-thick

sections

Immohistochemical

-LRB-

IHC

-RRB-

methodology

was

used

to

visualize

the

expression

of

αS

and

hyperphosphorylated

τ

-LRB-

HPτ

-RRB-

The

sections

were

deparaffinized

and

rehydrated

according

to

a

routine

procedure

For

αS

IHC

the

sections

were

autoclaved

-LRB-

°C

-RRB-

in

citrate

buffer

for

min

and

pretreated

with

formic

acid

at

room

temperature

for

min

Monoclonal

antibodies

to

human

-LRB-

Novocastra

Newcastle

upon

Tyne

UK

-RRB-

at

a

dilution

of

and

to

human

HPτ

at

a

dilution

of

-LRB-

Innogenetics

Ghent

Belgium

-RRB-

were

applied

For

detection

Histostain

SP

kit

-LRB-

Zymed

San

Francisco

CA

-RRB-

was

used

with

Romulin

AEC

chromogen

-LRB-

Biocare

Medical

Walnut

Creek

CA

-RRB-

The

expression

of

αS

was

assessed

in

brain

regions

-LRB-

-RRB-

medulla

with

dmV

-LRB-

-RRB-

pons

with

LC

and

raphe

nucleus

-LRB-

RN

-RRB-

-LRB-

-RRB-

midbrain

with

SN

-LRB-

-RRB-

BFB

including

nbM

AC

and

transentorhinal

cortex

-LRB-

-RRB-

posterior

hippocampus

at

the

level

of

geniculate

nucleus

including

the

region

of

the

hippocampus

and

temporo-occipital

gyrus

-LRB-

-RRB-

insular

cortex

-LRB-

-RRB-

anterior

cingulate

gyrus

-LRB-

-RRB-

superior

temporal

gyrus

-LRB-

Broadman

area

-RRB-

-LRB-

-RRB-

frontal

cortex

-LRB-

Broadman

area

and

-LRB-

-RRB-

parietal

cortex

-LRB-

Broadman

areas

-RRB-

The

selection

of

regions

was

based

on

the

currently

used

staging

systems

-LSB-

-RSB-

-LRB-

See

Fig.

-RRB-

HPτ

IHC

was

carried

out

on

sections

from

hippocampus

temporal

and

occipital

cortices

and

the

regional

distribution

of

AD-related

neurofibrillary

pathology

was

subdivided

into

stages

-LRB-

I-VI

-RRB-

as

has

been

described

previously

-LSB-

-RSB-

The

number

of

αS-IR

inclusions

was

counted

within

the

microscopic

field

at

magnification

-LRB-

diameter

of

mm

-RRB-

and

assessed

semiquantitatively

in

all

brain

areas

examined

The

total

thickness

of

the

cortical

grey

matter

and

AC

were

assessed

according

to

the

established

pathological

guidelines

-LSB-

-RSB-

and

rated

as

follows

mild

-LRB-

sparse

inclusions

at

-RRB-

moderate

-LRB-

inclusion

in

low

power

field

at

magnification

-RRB-

severe

-LRB-

inclusions

in

low

power

field

at

magnification

-RRB-

very

severe

-LRB-

numerous

inclusions

-RRB-

In

the

nbM

and

all

subcortical

regions

αS-IR

inclusions

were

counted

unilaterally

within

entire

nuclei

and

assessed

following

an

arbitrary

grading

system

in

nbM

and

SN

mild

-LRB-

inclusions

-RRB-

moderate

-LRB-

inclusions

-RRB-

severe

-LRB-

inclusions

-RRB-

in

LC

and

dmV

mild

-LRB-

inclusions

-RRB-

moderate

-LRB-

inclusion

-RRB-

severe

-LRB-

inclusions

-RRB-

Several

inclusions

within

one

neuron

were

counted

as

a

single

inclusion

The

αS-IR

structures

were

designated

as

being

present

-LRB-

-RRB-

or

not

-LRB-

-RRB-

in

raphe

nucleus

and

region

of

the

hippocampus

If

no

αS-IR

inclusions

were

identified

in

the

sections

of

medulla

pons

midbrain

or

BFB

the

result

was

verified

in

at

least

consecutive

sections

i.e.

the

subsequent

and

sections

were

stained

This

was

done

in

order

to

increase

the

likelihood

of

capturing

incipient

neurons

with

αS-IR

inclusions

Results

Assessment

of

clinical

data

The

αS-positive

subjects

examined

included

-LRB-

-RRB-

patients

with

a

clinical

diagnosis

of

a

neurodegenerative

disorder

-LRB-

-RRB-

patients

with

other

neurological

disorders

and

-LRB-

-RRB-

individuals

in

whom

the

clinical

information

indicated

that

they

had

no

neurological

impairment

The

mean

age

at

death

was

years

ranging

from

to

years

and

the

gender

was

rather

evenly

distributed

-LRB-

males

-RRB-

Frequency

of

αS-immunoreactivity

in

the

most

vulnerable

anatomical

regions

The

most

frequently

affected

regions

in

the

αS-positive

subjects

were

dmV

-LRB-

-RRB-

and

SN

-LRB-

-RRB-

where

the

αS-IR

was

seen

in

of

the

analyzed

subjects

The

LC

was

affected

in

-LRB-

-RRB-

of

subjects

making

this

area

the

second

most

vulnerable

nuclei

The

large

neurons

in

the

nbM

were

αS-immunopositive

in

of

cases

-LRB-

-RRB-

whereas

the

involvement

of

AC

particularly

the

cortico-medial

nuclear

group

was

seen

in

-LRB-

-RRB-

of

subjects

Staging

of

Parkinson

disease-related

αS

pathology

according

to

Braak

and

the

frequency

of

dementia

and

extrapyramidal

symptoms

Out

of

the

αS-positive

subjects

-LRB-

-RRB-

displayed

a

distribution

pattern

of

αS-IR

that

was

compatible

with

the

current

staging

systems

of

PD/DLB-related

synucleinopathies

-LSB-

-RSB-

Braak

stage

was

applicable

for

subjects

for

subjects

and

for

subjects

-LRB-

Table

-RRB-

When

all

subjects

with

severe

AD-related

neurofibrillary

pathology

i.e.

Braak

's

AD

stage

V-VI

were

excluded

cases

of

the

subjects

remained

Notably

only

of

the

subjects

with

PD-related

Braak

stage

and

of

subjects

with

PD-related

Braak

stage

were

demented

and/or

had

EPS

It

is

noteworthy

that

when

only

demented

subjects

were

included

in

the

analysis

-LRB-

out

of

-RRB-

-LRB-

-RRB-

were

assigned

to

PD-related

Braak

Similarly

when

only

subjects

with

EPS

were

included

in

the

analysis

-LRB-

out

of

-RRB-

-LRB-

-RRB-

were

in

the

PD-related

Braak

stages

Table

of

Braak

staging

and

the

incidence

of

dementia

and

extrapyramidal

signs

-LRB-

EPS

-RRB-

in

each

stage

Categorization

of

the

distribution

of

αS

pathology

following

the

recommendations

by

the

consortium

on

DLB

international

workshop

i.e.

McKeith

's

categorization

and

the

frequency

of

dementia

and

extrapyramidal

symptoms

Sixty-six

subjects

fulfilled

Mc

Keith

's

criteria

for

the

brainstem

predominant

form

for

the

limbic

-LRB-

transitional

-RRB-

and

for

the

diffuse

neocortical

form

of

DLB

-LRB-

Table

-RRB-

Table

of

neuropathological

categorization

as

recommended

by

the

consortium

on

DLB

international

workshop

i.e.

McKeiths

categorization

and

the

incidence

of

dementia

and

extrapyramidal

signs

-LRB-

EPS

-RRB-

in

each

category

Fifty-seven

percent

of

subjects

with

the

diffuse

neocortical

form

of

DLB

were

demented

and

displayed

EPS

-LRB-

Table

-RRB-

When

AD-related

pathology

was

taken

into

account

as

suggested

by

McKeith

and

colleagues

-LSB-

-RSB-

-LRB-

Table

-RRB-

the

percentage

of

demented

in

the

high

likelihood

category

varied

from

to

Irrespective

of

the

αS

pathology

in

Braak

's

AD

stage

V-VI

all

subjects

were

demented

Notably

when

only

demented

subjects

were

included

in

the

analysis

and

the

subject

with

severe

AD-related

pathology

-LRB-

Braak

's

AD

stage

V-VI

-RRB-

were

excluded

-LRB-

-RRB-

were

assigned

to

a

high

likelihood

category

of

DLB

Table

of

likelihood

that

the

pathological

findings

are

associated

with

a

DLB

clinical

syndromeCategory

of

Lewy

body

type

pathologyAlzheimer

type

pathologyBraak

stage

stage

III-IVBraak

stage

V-VIBrainstem

predominant

n

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Low

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Low

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Limbic

transitional

n

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Intermediate

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Low

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Diffuse

neocortical

n

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

High

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Intermediate

n

demented

-LRB-

-RRB-

with

EPS

-LRB-

-RRB-

Atypical

cases

i.e.

cases

that

could

not

be

classified

as

recommended

Thirty-nine

cases

were

not

classifiable

as

recommended

and

thus

were

assigned

as

being

atypical

i.e.

neither

Braak

staging

nor

McKeith

categorization

systems

could

be

applied

The

deviating

topographical

distribution

of

αS-IR

inclusions

of

these

subjects

is

shown

in

Table

In

four

subjects

the

BFB

nuclei

-LRB-

AC

predominant

-RRB-

were

severely

affected

-LRB-

cases

-RRB-

together

with

some

cortical

inclusions

whereas

the

brainstem

had

been

preserved

Five

subjects

displayed

isolated

minor

involvement

of

SN

without

any

αS-IR

inclusions

in

the

lower

brainstem

nuclei

-LRB-

cases

-RRB-

In

six

subjects

-LRB-

cases

-RRB-

minor

involvement

of

both

SN

and

BFB

nuclei

was

detected

-LRB-

cases

-RRB-

In

addition

to

these

two

areas

three

cases

exhibited

severe

αS

pathology

in

AC

-LRB-

cases

AC

predominant

-RRB-

In

seven

subjects

some

inclusions

were

seen

in

the

BFB

SN

and

LC

but

not

in

the

dmV

-LRB-

cases

-RRB-

In

the

final

subjects

-LRB-

cases

-RRB-

inclusions

were

seen

in

the

dmV

and

SN

but

not

in

the

LC

together

with

variable

affection

of

BFB

and

other

cortical

regions

In

only

minority

of

these

cases

EPS

symptoms

were

seen

-LRB-

-RRB-

whereas

dementia

was

more

common

-LRB-

-RRB-

In

cases

dementia

was

due

to

AD-related

neurofibrillary

pathology

-LRB-

Braak

stage

V-VI

-RRB-

in

six

cases

numerous

multifocal

microscopic

infarcts

and

concomitant

severe

white

matter

rarefaction

was

considered

as

the

causative

agent

regarding

dementia

and

in

one

cases

neuropathological

lesions

consistent

with

frontotemporal

dementia

with

ubiquitin

only

lesions

were

seen

Table

distribution

of

αS

immunoreactive

lesions

in

the

atypical

cases

i.e.

not

classifiable

following

current

recommendationsIDAgeSexEPSDemAD

stageTopographical

distribution

of

αS-immunoreactive

structuresdmVRNLCSNnbMACTrEnt

EPS

extrapyramidal

signs

Dem

clinical

signs

of

dementia

AD

stage

the

stage

of

Alzheimer

's

disease

related

neurofibrillary

pathology

stages

as

recommended

by

Braak

from

to

VI.

dmV

dorsal

motor

nucleus

of

vagus

RN

raphe

nucleus

LC

locus

coeruleus

SN

substantia

nigra

nbM

nucleus

basalis

of

Meynert

AC

amygdaloid

complex

TrEntCx

transentorhinal

cortex

region

of

the

Cornu

Ammonis

of

the

hippocampus

Temp-Occ

temporo-occipital

gyrus

Ins

Cx

insular

cortex

CG

cingulate

gyrus

TCx

temporal

cortex

FCx

frontal

cortex

PCx

parietal

cortex

not

available

The

αS-immunoreactive

inclusions

were

examined

in

the

total

thickness

of

the

cortical

grey

matter

and

AC

and

rated

as

follows

mild

-LRB-

sparse

inclusions

in

-RRB-

moderate

-LRB-

inclusion

in

magnification

-RRB-

severe

-LRB-

inclusions

in

magnification

-RRB-

very

severe

-LRB-

numerous

inclusions

-RRB-

in

the

nbM

and

subcortical

regions

αS

immunoreactive

inclusions

were

counted

unilaterally

within

entire

nuclei

and

assessed

following

an

arbitrary

grading

system

in

nbM

and

SN

mild

-LRB-

inclusions

-RRB-

moderate

-LRB-

inclusions

-RRB-

severe

-LRB-

inclusions

-RRB-

and

in

LC

and

dmV

mild

-LRB-

inclusions

-RRB-

moderate

-LRB-

inclusion

-RRB-

severe

-LRB-

inclusions

-RRB-

In

Raphe

nucleus

and

region

of

the

hippocampus

αS-immunoreactive

structures

-LRB-

inclusion

and/or

neurites

-RRB-

were

marked

to

be

present

-LRB-

-RRB-

or

not

-LRB-

-RRB-

Discussion

Most

of

our

-LRB-

-RRB-

αS-positive

cases

could

be

assigned

to

one

of

the

six

PD

stages

as

described

by

Braak

and

also

into

the

brainstem

limbic

or

diffuse

neocortical

neuropathological

category

as

recommended

by

McKeith

and

colleagues

-LSB-

-RSB-

Braak

and

colleagues

depicted

the

topographical

distribution

of

αS-IR

structures

by

assessing

αS-positive

subjects

-LRB-

incidental

and

symptomatic

PD

patients

-RRB-

-LSB-

-RSB-

The

initial

intent

of

Braak

and

colleagues

was

not

to

correlate

the

designated

neuropathological

stages

with

clinical

symptoms

however

this

was

later

contemplated

-LSB-

-RSB-

Stages

and

i.e.

stages

where

αS

pathology

is

confined

to

the

dmV

and/or

LC

are

considered

to

be

presymptomatic

whereas

EPS

appear

and

the

cognitive

decline

increases

with

each

stage

In

stage

when

SN

is

affected

EPS

appear

and

subsequently

in

stage

when

amygdaloid

complex

transentorhinal

region

and

temporo-occipital

gyrus

become

involved

moderate

cognitive

impairment

is

observed

-LRB-

MMSE

scores

-RRB-

and

finally

in

stage

and

when

the

neocortex

succumbs

to

the

pathology

severe

cognitive

impairment

is

evident

-LRB-

MMSE

scores

and

respectively

-RRB-

-LSB-

-RSB-

Our

results

also

suggest

that

the

risk

of

EPS

increases

with

disease

progression

though

not

to

the

same

extent

as

earlier

reported

In

our

study

we

found

one

subject

with

EPS

already

in

stage

whereas

of

our

cases

in

stage

displayed

EPS

and

more

importantly

no

EPS

had

been

reported

in

of

subjects

who

exhibited

widespread

pathology

-LRB-

Braak

stages

-RRB-

i.e.

this

being

compared

with

the

previously

reported

by

Braak

and

colleagues

-LSB-

-RSB-

The

initial

decline

in

cognition

was

postulated

to

occur

already

during

stages

and

i.e.

around

the

same

time

when

the

initial

manifestation

of

somatosensor

dysfunction

start

to

appear

When

assessing

subjects

Braak

and

colleagues

reported

that

of

their

subjects

in

stage

in

stage

in

stage

and

in

stage

were

demented

-LSB-

-RSB-

This

is

clearly

in

odds

with

our

results

where

the

percentage

of

demented

increased

from

to

between

stages

It

is

noteworthy

that

when

only

demented

subjects

were

included

were

assigned

to

PD-related

Braak

stages

and

when

only

subjects

with

EPS

were

included

were

in

the

PD-related

Braak

stages

Thus

the

key

difference

between

our

study

when

compared

to

most

other

clinico-pathological

correlation

studies

that

have

reported

good

correlation

between

risk

of

disease

and

progression

of

pathology

is

the

study

design

-LSB-

-RSB-

Consequently

when

we

only

included

subjects

with

clinical

signs

in

our

analysis

the

correlation

between

stage/severity

of

αS

pathology

and

EPS/dementia

was

excellent

in

line

with

previous

reports

PD

and

DLB

are

distinguished

as

separate

clinical

entities

and

in

the

consortium

of

the

DLB

international

workshop

subdivided

the

neuropathological

features

of

DLB

into

three

categories

brainstem

predominant

limbic

and

diffuse

neocortical

type

-LSB-

-RSB-

The

foundation

of

these

three

categories

is

also

based

on

the

progressive

propagation

of

αS

pathology

along

a

caudo-striatal

axis

Similarly

to

the

Braak

staging

-LSB-

-RSB-

when

applying

this

categorization

it

is

presumed

that

of

subjects

with

widespread

αS

pathology

i.e.

in

the

diffuse

neocortical

stage

all

will

be

demented

and

display

EPS

When

we

followed

the

classification

strategy

proposed

by

McKeith

and

colleagues

-LSB-

-RSB-

our

results

also

differed

from

those

expected

i.e.

only

a

subset

of

our

subjects

who

were

classified

to

be

in

the

diffuse

neocortical

category

displayed

dementia

and/or

EPS

-LRB-

and

respectively

-RRB-

In

line

with

the

above

when

only

demented

subjects

were

included

in

the

analysis

the

correlation

between

αS

pathology

and

dementia

was

close

to

excellent

-LRB-

-RRB-

The

clinical

relevance

of

cortical

αS

pathology

in

relation

to

dementia

is

a

matter

of

intense

debate

Some

authors

have

emphasized

their

key

causative

role

-LSB-

-RSB-

whereas

others

have

reported

that

there

may

be

abundant

cortical

pathology

in

non-demented

PD

patients

-LSB-

-RSB-

as

well

as

in

neurologically

unimpaired

subjects

-LSB-

-RSB-

It

is

noteworthy

that

the

current

study

differs

significantly

from

most

other

studies

since

it

is

based

on

neuropathologiacal

findings

rather

than

on

clinical

presentation

Our

results

emphasize

that

abundant

pathology

may

be

detected

in

many

subjects

without

notable

signs

of

dementia

-LRB-

MMSE

-RRB-

-LRB-

-RRB-

if

it

is

sought

This

has

one

unexpected

consequence

i.e.

a

detailed

regional

assessment

of

αS

pathology

can

not

reliably

predict

the

clinical

status

observed

premortem

-LSB-

-RSB-

There

has

been

much

discussion

concerning

the

significance

and

influence

of

concomitant

AD-related

pathology

particularly

as

this

is

quite

frequently

seen

in

aged

subjects

Therefore

the

revised

consensus

criteria

have

recommended

taking

AD-related

pathology

into

account

while

assessing

subjects

with

suspected

DLB

-LSB-

-RSB-

It

was

presumed

that

this

would

increase

the

diagnostic

specificity

since

it

was

believed

that

the

pathological

substrate

behind

DLB

was

indeed

αS

pathology

When

we

assessed

our

unique

material

we

found

that

within

the

neuropathological

high

likelihood

categories

of

DLB

i.e.

those

cases

where

limbic/diffuse

neocortical

αS

pathology

is

combined

with

mild/moderate

AD-related

changes

of

subjects

remained

cognitively

intact

However

when

we

examined

only

demented

subjects

without

severe

AD-related

pathology

-LRB-

Braak

's

AD

stage

V-VI

-RRB-

were

assigned

to

a

high

likelihood

category

of

DLB

This

shows

that

when

αS

pathology

is

examined

in

clinically

demented

subjects

the

correlation

received

between

particular

pathologic

change

and

dementia

is

good

It

is

noteworthy

that

with

respect

of

AD-related

neurofibrillary

pathology

all

cases

in

the

neocortical

stage

-LRB-

Braak

stage

V-VI

-RRB-

were

indeed

demented

One

important

issue

with

respect

to

the

pathogenesis

of

synucleinopathies

is

not

only

to

understand

the

molecular

mechanisms

behind

the

intracytoplasmic

aggregation

of

αS

but

also

to

appreciate

where

this

process

first

appears

and

how

it

may

progress

through

the

brain

Thus

many

recent

studies

have

attempted

to

localize

the

most

vulnerable

neuronal

populations

In

this

study

dmV

and

SN

were

found

to

be

equally

susceptible

nuclei

but

even

earlier

affected

structures

have

been

reported

to

appear

in

the

spinal

cord

dmV

olfactory

bulb

and

AC

-LSB-

-RSB-

Thus

mapping

out

the

trigger

site

for

αS

pathology

appears

to

depend

on

the

screening

process

i.e.

if

one

screens

medulla

alone

those

cases

where

lesions

are

restricted

to

other

areas

-LRB-

e.g.

SN

-RRB-

are

not

found

and

vice

versa

At

variance

to

the

studies

of

Del

Tredici

and

Braak

-LSB-

-RSB-

we

identified

a

number

of

subjects

where

dmV

and/or

LC

were

not

affected

but

αS-IR

inclusions

were

found

in

the

SN

BFB

and

or

other

cortical

regions

and

thus

the

distribution

of

αS

pathology

did

not

strictly

follow

the

caudo-rostral

propagation

pattern

described

by

Braak

and

colleagues

-LSB-

-RSB-

Thus

the

proposed

ascending

pathway

is

not

the

only

possible

route

and

our

results

indicate

that

pathology

can

emerge

simultaneously

in

subcortical

and

cortical

regions

Jellinger

has

also

reported

subjects

with

multiple

αS-IR

inclusions

but

with

preservation

of

medullary

nuclei

-LSB-

-RSB-

Furthermore

in

some

subjects

we

found

the

AC

to

be

devoid

of

pathology

although

αS-IR

structures

were

detected

elsewhere

in

the

neocortex

This

refutes

the

proposal

that

in

order

to

have

neocortical

involvement

then

the

subcortical

lesions

have

to

expand

through

the

basal

forebrain

nuclei

In

addition

according

to

Braak

and

colleagues

-LSB-

-RSB-

the

αS

pathology

in

previously

involved

regions

should

become

exacerbated

with

disease

progression

It

is

difficult

to

evaluate

this

proposal

when

one

takes

into

account

the

increasing

neuronal

loss

If

these

two

pathological

hallmarks

are

linked

in

a

causative

chain

the

load

of

αS-IR

structures

should

show

an

inverted

u-shape

distribution

over

time

where

the

number

of

inclusions

would

increases

with

the

progression

of

the

disease

until

the

neurons

start

to

die

-LSB-

-RSB-

We

observed

some

cases

with

severe

αS

pathology

in

AC

and

in

that

situation

this

structure

was

either

only

involved

region

or

was

affected

together

with

BFB

and

SN

All

these

subjects

were

demented

and

exhibited

coexistent

severe

AD-related

pathology

-LRB-

Braak

AD

stage

V-VI

-LSB-

-RSB-

-RRB-

In

one

case

the

dementia

was

considered

to

be

vascular

in

origin

This

is

in

line

with

the

results

of

Uchikado

and

colleagues

who

have

reported

the

AC

predominant

form

to

be

common

finding

among

patients

with

AD

-LSB-

-RSB-

In

conclusion

our

results

confirm

that

the

current

staging/categorization

systems

can

readily

be

applied

to

most

of

the

subjects

when

assessing

regional

distribution

of

αS-pathology

It

is

noteworthy

however

that

outliers

do

exist

and

in

these

cases

the

presumed

distribution

may

have

been

modified

by

other

coexisting

pathologies

or

genetic

factors

-LSB-

-RSB-

It

is

intriguing

that

around

every

second

subject

displaying

abundant

pathology

did

remain

neurologically

intact

It

is

noteworthy

that

these

results

were

seen

when

a

rather

unselected

sample

of

cases

was

investigated

It

has

been

suggested

that

the

key

lesions

begin

to

develop

a

considerable

time

prior

to

the

appearance

of

clinical

symptoms

-LSB-

-RSB-

but

based

on

our

results

there

do

seem

to

be

some

subjects

who

can

tolerate

substantial

amounts

of

pathology

As

only

of

subjects

with

widespread

αS

pathology

were

demented

-LRB-

MMSE

-RRB-

and

displayed

EPS

the

clinical

relevance

of

αS-IR

inclusions

as

such

still

remains

to

be

resolved

Hitherto

the

aggregation

of

αS

has

been

thought

to

lead

to

neuronal

death

but

recent

evidence

has

suggested

that

the

formation

of

large

inclusions

may

actually

represent

a

protective

process

-LSB-

-RSB-

Many

biophysical

studies

have

suggested

that

it

is

a

protofibrillar

form

of

αS

rather

than

the

mature

fibrils

that

are

responsible

for

the

cell

death

-LSB-

-RSB-

and

moreover

the

fibrillar

form

that

is

typically

observed

at

autopsy

may

actually

be

a

sign

of

a

well

functioning

neuroprotection

-LSB-

-RSB-

Thus

when

we

are

assessing

regional

distribution

of

αS

pathology

the

question

arises

if

we

are

really

evaluating

a

stage

of

degeneration

or

conversely

monitoring

the

level

of

functional

neuroprotection

O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

lewy body dementia
parkinson disease
α-synuclein