# Presentation: 650312

## Precursors, Insulators, and Consequences of Inhalant Use

**RTI International**
- Diana H. Fishbein, Ph.D. - Principal Investigator
- Christopher P. Krebs, Ph.D. - Co-Investigator
- Tara Williams, M.A. - Research Analyst
- Nancy Trevarthen, M.A. - Data Collection Task Leader
- Jane Hammond, Ph.D. – Developmental Psychologist
- Barbara Flannery, Ph.D. - Psychopharmacologist
**Funded by**** **
- National Institute on Drug Abuse
- (Grant #R01 DA15935 )

## What do we know about inhalant users?

- Age of onset (mean = ~12) often precedes that of other drugs and users are typically young
- Males and females are equally as likely to use inhalants
- Inhalant use is associated with low SES, family instability, and depression
- Inhalant use varies somewhat by race/ethnicity*
- Whites = 9.7%
- Hispanics = 9.7%
- Native Americans/Alaskan Natives = 12.4%
- Blacks = 5.9%
*** NSDUH 2000 data, 12-17 year-olds, self-reported lifetime inhalant use**

## Lifetime Prevalence of Cocaine and Inhalant Use: NSDUH and MTF

## Background

- Evidence that inhalant use produces serious cognitive, neurological, social, and behavioral consequences
- Existing research studies have employed retrospective designs
- There are no credible studies of the risk or protective factors (i.e., precursors) for the onset of inhalant use
- So-called “consequences” may instead antedate use and act as precursors that are, then, exacerbated by subsequent inhalant use

## The Inhalants Project overcomes limitations of existing research

- A stocked pond of inhalant users (Cicero, IL): data from national evaluation study showed >18% of 7th graders in Cicero reported using inhalants in past 30 days
- Prospective panel research design: collects data before onset and after inhalant use
- Emphasis on neurocognitive precursors and consequences
- Studies interactions between neurocognitive, psychosocial, background, cultural, and experiential factors
- Identifies differential etiological pathways to inhalant use versus other drug use and no use

## Prospective Panel Research Design

*** Primary caregivers are also interviewed at baseline**

| Child Age | Baseline Testing* | 12-month Follow-up | 24-month Follow-up |
| --- | --- | --- | --- |
| 10 Years |  |  |  |
| 11 Years |            |  |  |
| 12 Years |  |  |  |
| 13 Years |  |  |  |
| 14 Years |  |  |  |

- Three waves of data collection (perhaps more?)
- Most youth have not used drugs prior to baseline
- A proportion of youth will begin to use, some chronically, over the course of the study

## Likely Candidates for Vulnerability and Exacerbating Effects

- Dimensions of cognitive and emotional functions found to be predictive of substance abuse in general and that are vulnerable to inhalants’ adverse effects
- Depression
- Cultural influences given concentrated pockets of reported use
- Parental history of drug use and mental illness, involvement and disciplinary practices
- Lack of knowledge within family and community about inhalants
- Peer attitudes and use
- Academic performance and school involvement
**A possible unique interaction between the above factors**

## Focal Point: Executive Cognitive Function (ECF) Deficits

- Compromises the ability to interpret social cues during interpersonal interactions
- Leads to misperceptions of threat or hostility in conflict situations
- Permits negative affective states and other maladaptive responses to dominate
- Heightened sensitivity to rewards
- Impulsivity and Inattention
- Insensitivity to Consequences

## Emotional Regulation

**PFC modulates functions of anterior cingulate and limbic system**
- Substrate for motivation and emotion
- Ascribes feeling to environmental inputs
- Stimulates emotionally driven behaviors
- Physiological stress responses
-    altered
- Serotonin and dopamine terminal
-    projections involved in rewarding
-    and addictive properties of drugs
-    and other forms of novelty

## Disconnect in Brain’s Regulatory System may Heighten Risk 

- Deficits in **prefrontal cortex** associated with disinhibition, insensitivity to penalty, impaired decision making, dysregulated affect.
- Instability in **limbic system** associated with inability to perceive and regulate emotion = poor self regulation

**Disconnect in Brain’s Regulatory System may Heighten Risk**** **

## Alters brain function, disengages coping mechanisms, and compromises ability to execute rational choices
Increases the likelihood of psychopathology: depression, drug abuse & violent behavior 
Genetic vulnerabilities affect particular behavioral outcomes of stress
Positive attributes of individual or environment provides protection from drug use. 

- Increases the likelihood of psychopathology: depression, drug abuse & violent behavior
- Genetic vulnerabilities affect particular behavioral outcomes of stress
- Positive attributes of individual or environment provides protection from drug use.

**Chronic stress primes the brain for drug self-administration**

## The Adolescent Brain

- Particularly vulnerable to environmental inputs, including stress and drug effects
- Effects are longstanding
- Prefrontal cortex not fully developed until early adulthood
- Unique stage of change in metabolism, pruning, and increased efficiency in prefrontal function
- Emotional centers (limbic) without checks and balances
- Greater sensitivity to rewards, less inhibition
- Seek altered states of consciousness

## Data Collected from Youth

- Demographic and Environmental: neighborhood, school, violence, gangs, peer use, etc.
- Behavioral: drug use, aggression, school, crime
- Attitudinal: toward drugs, well being, safety
- Social/Psychological: family functioning, depression, peers, social supports, maltreatment
- Neurocognitive
- Raven’s Progressive Matrices: non-verbal IQ
- Tower of London: memory and executive cognitive function
- Stroop Interference Task: cognitive flexibility
- Logan Stop-Signal Task: impulsivity and distractibility
- Rogers Task: risk taking and sensitivity to consequences*
- Facial Recognition Task: emotional recognition*

**Notes:**
Behavioral – school, violence, delinquency, situational
Attitudinal – towards school, family, peers/friends, life, future, drugs
Social/Psychological – trauma, depression, social support, coping, pro-social indicators

## Current Status of Inhalants Project

- Successfully recruited and collected baseline data from 553 dyads: 10-12 yr olds and caregivers
- More than half way through wave 2 of data collection with >300 youth retested
- 94% retention rate
- Analysis of baseline data has commenced
- Descriptives
- Relationship between high risk behaviors and cognitive function
- Moderating effects of cognitive function on relations between experiential factors and high risk behaviors

## Background Data on Youth

- Gender: 48% male
- Age:
- 27% are 10
- 40% are 11
- 33% are 12
- Race/Ethnicity: 90% Hispanic, 10% White
- Grade:
- 10% in 4th
- 33% in 5th
- 41% in 6th
- 16% in 7th

## Attitudes Toward Drug Use

- 78% think using marijuana poses “great” risk
- 78% think using cocaine poses “great” risk
- 72% think using heroin poses “great” risk
**54%** think using inhalants poses “great” risk
**39%** think using inhalants is more harmful than other illicit drugs

## Adversity Data on Youth

- 16% have seen family members beating each other
- 35% have witnessed neighborhood violence
- 15% have seen weapon used or someone threatened with a weapon
- Boys have significantly higher rates of early trauma exposure and lifetime stressful events than girls
- Kids with problems tend to have multiple problems not just one or two: “all or none”

## Baseline Data on Drug Use*

- 5% reported having used alcohol
- <1% reported having used marijuana
- 3% reported having used inhalants
- * Most who have tried drugs have done so only once or twice and are 12 years old.

## Baseline Data on Primary Caregiver Sample

- Gender: 46% male
- Age:
- Range: 25-72
- Mean: 37
- Race/Ethnicity: 94% Hispanic, 5% White
- Annual Income Mean: $28,623
- 33% have graduated high school or obtained GED
- 26% have lived in the U.S. for less than 10 years
- 16% have hit their child with a belt, brush, or stick in past 12 months
- 35% have spanked their child with their hand

## Baseline Data on Primary Caregiver Sample, cont.

- 62% have talked to their children about the dangers of using drugs “many times” in the past 12 months
- 9% have not talked about drugs at all
- 38% have spoken to their children about the dangers of using inhalants “many times” in the past 12 months
- 31% have not talked about inhalants at all
- 71% “strongly agreed” they wish they knew more about what to say to their child about drugs
- 15% “strongly agreed” and 34% “agreed” there are places in the community they can turn to learn more about how to prevent their child from using drugs

## Factors Predicting Dysregulation (A Precursor to Drug Abuse)*

- Positive Outlook, Depression, and Symptoms of PTSD.
- Higher Emotional Abuse, Physical Abuse and Physical Neglect scores (not sexual abuse or emotional neglect).
- Other experiential and background factors are correlated highly significantly, but not when considered relative to one another.
- Interactions between child abuse and all primary cognitive variables, esp IQ (e.g., child abuse + deficit = dysreg)
- Interactions between depression with all primary cognitive variables, esp IQ (e.g., depression + deficit = dysreg).
- * Regression analyses adjusted for age and gender

## Future of the Inhalants Project

- Scheduled to wrap-up data collection in early 2007
- Goals:
- isolate risk and protective factors for and consequences of inhalant use
- Identify differential, developmental changes over time
- Generate much-needed data on the use and users of inhalants
- Inform the development and implementation of targeted prevention programs
- Conduct similar research in other places that are plagued by inhalant use (e.g., Central and/or South America)