PROSPECTIVE STUDY OF AIR POLLUTION AND BRONCHITIC

SYMPTOMS IN CHILDREN WITH ASTHMA

ONLINE DATA SUPPLEMENT

Rob McConnell, M.D.

Kiros Berhane, Ph.D.

Frank Gilliland, M.D., Ph.D.

Jassy Molitor

Duncan Thomas

Fred Lurmann

Edward Avol, M.S.

W. James Gauderman, Ph.D.

John M. Peters, M.D.RESULTS

Table E1: Pearson correlation coefficients of 4

- year average pollutant concentrations across study communities

(N=12)

NO 2 O 3 PM 10 PM 2.5 PM 10

- 2.5 Inorganic

acid Organic

acid EC OC

NO 2 1

O 3

- 0.17 1

PM 10 0.63* 0.20 1

PM 2.5 0.75† 0.21 0.96† 1

PM 10

- 2.5 0.43 0.18 0.94† 0.82† 1

Inorganic acid 0.84† 0.36 0.72† 0.83† 0.51 1

Organic acid 0.83† 0.33 0.83† 0.88† 0.69* 0.94† 1

EC 0.92† 0.01 0.86† 0 .92† 0.70* 0.88† 0.90† 1

OC 0.58* 0.18 0.97† 0.90† 0.95† 0.64* 0.81† 0.81† 1

*P < .05; † P < .01The between

– community effect estimates for the pollutants examined were, in general,

not significant in the presence of other pollutants in two pollutant models (see Table E2).

The effect estimates for NO 2 ( ? = 0.017/ppb) and for EC ( ? = 0.441/μg/m 3 ) in single

pollutant models were markedly attenuated in models with PM 2.5 . The effect of NO 2 was

modestly reduced when adjusted for PM 10 , EC, or OC. The effect of PM 2.5 ( ? = 0.026/μg/m

3 ) was markedly reduced, when adjusted for NO 2 . No pollutant had a

consistent significant association with symptoms in models adjusted for other pollutants.

Table E2: Two pollutants models of between

- community

ef fects (4

- year average

concentrations; N=12) among children with asthma*

Main

Pollutant Adjustment pollutants

NO 2 O 3 PM 10 PM 2.5 PM 10

- 2.5 Inorganic

acid Organic

acid EC OC

NO 2 0.017 † 0.016† 0.014 0.0 09 0.017† 0.020 0.017 0.014 0.014

O 3

- 0.003

- 0.006

- 0.009

- 0.010

- 0.007

- 0.012

- 0.011

- 0.006

- 0.008

PM 10 0.004 0.013 0.011

- 0.027 0.043† 0.009 0.006

- 0.001 0.010

PM 2.5 0.016 0.029‡ 0.069 0.026 † 0.043† 0.036 0.034 0.02 5 0.037

PM 10

- 2.5 0.000 0.016

- 0.069

- 0.027 0.013 0.003

- 0.005

- 0.011

- 0.070

Inorganic

- 0.037 0.137† 0.035

- 0.069 0.089 0.098

- 0.044

- 0.073 0.044

acid

Organic

- 0.001 0.091† 0.039

- 0.035 0.078 0.094 0.069

- 0.027 0.050

acid

EC 0.097 0.443† 0.450 0.018 0.557 0.658 0.567 0.441 † 0.389

OC 0.020 0.059 0.004

- 0.043 0.213† 0.043 0.021 0.004 0.054

*Each row gives estimates (beta) for the indicated pollutant, adjusted for age, maternal and chi ld’s smoking history,

sex, and race, the within

- community effect of that pollutant and for both the between

- and within

- community effect

of the adjustment pollutant listed at the top of each column. The estimate for each pollutant in a single pollutant

mod el is presented along the diagonal (in bold). Estimates are expressed per ppb for NO 2 , O 3 , acid; per ? g/m 3 for

PM, elemental and organic carbon.

†P < .05; ‡ P < .01Figure E1

Figure E1: Odds ratios for the within

- community effects of NO2 and of organic carbon,

adjusted for each of the other pollutants examined.

A: Risk of Bronchitic Symptoms as a Function

of Yearly Deviation in NO 2

0.9 1.0 1.1 1.2 1.3 1.4 1.5

NO2+ O3(10-6) PM10 PM2.5 PM10-25 I ACID O ACID EC OC

Adjustment Air PollutantsOdds Ratio* / ppb B: Risk of Bronchitic Symptoms as a Function of Yearly

Deviation in OC

0.5 1.0 1.5 2.0 2.5 3.0 3.5

OC+ NO2 O3(10-6) PM10 PM2.5 PM10-25 I ACID O ACID EC

Adjustment Air PollutantsOdds Ratio* / (mcg / m3)

*All odds ratios were adjusted for age, maternal and child’s smoking history, sex, and

race, and for the between

- community effect of the pollutant indicated.

+NO2+ and OC+ indicate the within

- community odds ratio in a single pollutant model,

adjusted only for the between

- community effects of NO2 (A) and OC (B) and for

personal covariates. All other odds ratios are also for NO2 (A), or for OC (B), but

adjusted in addition for both within

- and between

- community effects of the adjustment

pollutant indicated.