Maternal Concentrations of Persistent Organochlorine Pollutants and the Risk of Asthma in Offspring: Results from a Prospective Cohort with 20 Years of Follow-up

http://dx.doi.org/10.1289/ehp.1206397



Table 2. Maternal and offspring characteristics of 872 mother–child pairs across tertiles of maternal PCB, HCB, and p,p´-DDE serum concentrations.
Characteristic 1st tertile 2nd tertile 3rd tertile p-Valuea
Values are mean ± SD, n, or n (%).
aDifferences in maternal age, fish intake, alcohol, prepregnancy BMI, birth weight, gestational age across tertiles of maternal POP concentrations were evaluated using F-test. Differences in previous births, smoking, maternal education, sex, asthma medication, asthma hospital diagnoses, and self-reported diagnoses, self-reported medication across tertiles of maternal POP concentrations were evaluated using chi-square test.
PCB concentration (pmol/mL) (range) 1.4–7.7 7.7–11.1 11.1–80.6  
Maternal        
Maternal age at birth (years) 27.6 ± 4.1 29.1 ± 3.9 30.4 ± 4.2 < 0.001
Fish intake (g/day) 18.8 ± 16.3 18.4 ± 13.4 20.6 ± 16.7 0.21
Alcohol (g/day) 2.5 ± 3.7 2.9 ± 3.3 3.4 ± 4.2 0.01
Previous births (% nulliparous) 152 (52.4) 160 (55.0) 188 (64.6) 0.02
Smoking during pregnancy (% no) 157 (57.5) 182 (66.4) 154 (56.2) 0.09
Maternal education (% higher academic) 37 (13.6) 42 (15.4) 46 (16.8) 0.02
Prepregnancy BMI (kg/m2) 21.5 ± 3.0 21.5 ± 3.1 21.3 ± 3.2 0.72
Offspring        
Birth weight (g) 3514.8 ± 507.7 3503.3 ± 563.8 3462.7 ± 541.1 0.47
Gestational age (days) 283 ± 10.8 283 ± 12.2 281 ± 12.3 0.03
Sex (% boys) 142 (49.0) 150 (51.6) 169 (58.1) 0.08
Asthma medication (n cases) 33 36 42 0.53
Asthma hospital diagnoses (n cases) 8 12 12 0.60
Self-reported diagnoses (n cases) 22 34 33 0.26
Current self-reported medication use (n cases) 11 18 19 0.35
HCB concentrations (ng/mL) (range) 0.1–0.5 0.5–0.6 0.6–2.5  
Maternal        
Maternal age at birth (years) 28.0 ± 4.1 28.9 ± 3.8 30.2 ± 4.2 < 0.001
Fish intake (g/day) 18.1 ± 14.5 19.5 ± 15.7 20.2 ± 16.3 0.24
Alcohol (g/day) 2.6 ± 3.8 3.0 ± 3.5 3.2 ± 3.9 0.14
Previous births (% nulliparous) 140 (48.3) 168 (57.7) 192 (66.0) < 0.001
Smoking during pregnancy (% no) 162 (59.6) 162 (59.3) 169 (61.2) 0.64
Maternal education (% higher academic) 36 (13.2) 44 (16.2) 45 (16.3) 0.22
Prepregnancy BMI (kg/m2) 21.0 ± 2.5 21.2 ± 2.4 22.1 ± 4.0 < 0.001
Offspring        
Birth weight (g) 3483.2 ± 503.1 3534.7 ± 534.8 3463.0 ± 572.8 0.25
Gestational age (days) 283 ± 11.7 283 ± 10.9 281 ± 12.8 0.04
Sex (% boys) 147 (50.7) 155 (53.3) 159 (54.6) 0.63
Asthma medication (n cases) 28 35 48 0.04
Asthma hospital diagnoses (n cases) 8 12 12 0.60
Self-reported diagnoses (n cases) 20 34 35 0.07
Current self-reported medication use (n cases) 6 20 22 0.01
p,p´-DDE concentrations (ng/mL) (range) 0.2–1.9 1.9–3.2 3.3–38.8  
Maternal        
Maternal age at birth (years) 28.0 ± 4.2 28.8 ± 4.0 30.3 ± 4.1 < 0.001
Fish intake (g/day) 19.1 ± 14.7 17.7 ± 14.4 20.9 ± 17.3 0.05
Alcohol (g/day) 2.4 ± 3.2 3.1 ± 3.9 3.4 ± 4.1 0.01
Previous births (% nulliparous) 148 (51.0) 171 (58.8) 181 (62.2) 0.05
Smoking during pregnancy (% no) 162 (58.5) 174 (64.4) 157 (57.3) 0.59
Maternal education (% higher academic) 35 (12.6) 38 (14.1) 52 (19.0) 0.03
Prepregnancy BMI (kg/m2) 20.9 ± 2.7 21.5 ± 2.9 21.8 ± 3.6 0.003
Offspring        
Birth weight (g) 3499.9 ± 533.5 3494.7 ± 519.8 3486.6 ± 561.1 0.96
Gestational age (days) 283 ± 11.7 282 ± 11.8 282 ± 12.0 0.49
Sex (% boys) 146 (50.3) 159 (54.6) 156 (53.6) 0.56
Asthma medication (n cases) 37 34 40 0.76
Asthma hospital diagnoses (n cases) 10 11 11 0.97
Self-reported diagnoses (n cases) 30 31 28 0.89
Current self-reported medication use (n cases) 16 16 16 0.99