Table 4.
Incidence RR of each DDE quartile of prenatal exposure compared to the first quartile
| Unadjusted (n = 199)
|
Adjusted (n = 177)a |
|||||||
|---|---|---|---|---|---|---|---|---|
| Incidence RR (95% CI)b |
Incidence RR (95% CI)b |
|||||||
| Infection type | 2nd quartile (n = 50) | 3rd quartile (n = 50) | 4th quartile (n = 50) | p-Value for trendc | 2nd quartile (n = 40) | 3rd quartile (n = 46) | 4th quartile (n = 45) | p-Value for trendc |
| 6-Month follow-up | ||||||||
| URTIs | 1.50 (1.05–2.13) | 1.06 (0.72–1.55) | 1.19 (0.82–1.73) | 0.91 | 1.56 (1.05–2.33)* | 1.15 (0.75–1.75) | 1.40 (0.90–2.16) | 0.24 |
| Otitis media | 1.27 (0.79–2.05) | 1.63 (1.04–2.57)* | 1.50 (0.95–2.38) | 0.04* | 1.03 (0.59–1.77) | 1.83 (1.09–3.07)* | 1.55 (0.90–2.68) | 0.07 |
| GI infections | 2.16 (1.02–4.55)* | 1.76 (0.81–3.82) | 1.67 (0.76–3.64) | 0.34 | 1.91 (0.84–4.35) | 1.66 (0.69–3.97) | 1.35 (0.54–3.42) | 0.58 |
| LRTIs | 1.52 (1.00–2.32)* | 1.01 (0.64–1.59) | 1.01 (0.64–1.59) | 0.75 | 1.40 (0.86–2.29) | 1.22 (0.72–2.05) | 0.96 (0.55–1.66) | 0.89 |
| All infectionsd | 1.49 (1.19–1.87)* | 1.23 (0.97–1.55) | 1.25 (0.99–1.57) | 0.22 | 1.38 (1.07–1.78)* | 1.33 (1.03–1.73)* | 1.27 (0.96–1.67) | 0.11 |
| 12-Month follow-up | ||||||||
| URTIs | 1.27 (0.98– 1.63) | 1.03 (0.79– 1.34) | 1.11 (0.85–1.44) | 0.85 | 1.34 (1.00–1.78)* | 1.09 (0.81–1.47) | 1.30 (0.96–1.78) | 0.27 |
| Otitis media | 1.00 (0.79–1.27) | 1.12 (0.89–1.42) | 1.08 (0.85–1.36) | 0.36 | 0.89 (0.68–1.17) | 1.08 (0.83–1.41) | 1.02 (0.76–1.35) | 0.72 |
| GI infections | 1.49 (1.00–2.23)* | 1.30 (0.86–1.96) | 1.20 (0.79–1.82) | 0.98 | 1.59 (1.03–2.47)* | 1.27 (0.81–2.00) | 1.43 (0.87–2.34) | 0.59 |
| LRTIs | 1.15 (0.85–1.55) | 0.96 (0.70–1.30) | 1.05 (0.78–1.42) | 0.89 | 1.07 (0.75–1.51) | 0.98 (0.69–1.40) | 1.00 (0.69–1.45) | 0.99 |
| All infectionsd | 1.17 (1.02–1.35)* | 1.08 (0.93–1.24) | 1.09 (0.95–1.26) | 0.59 | 1.13 (0.97–1.33) | 1.08 (0.92–1.26) | 1.13 (0.95–1.34) | 0.38 |
CI, confidence interval.
a
Model included mother’s age, season of birth, year of birth, breast-feeding duration, sex, socioeconomic status of the caregiver, tobacco use during pregnancy, village of residence, and number of children living with the participant.
b
Incidence RR when the given quartile was compared to the first quartile of exposure (Poisson regression).
c
p-Values for trends were calculated by Poisson regression in which the contaminant concentration (lipid-based) was entered as a continuous variable (log-transformed).
d
Only infections with a mean incidence > 1.0 episode/year/infant were included; see details in “Materials and Methods”).
*
p < 0.05.