Table 3.
Incidence RR of each PCB-153 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 | 1.08 (0.76–1.55) | 0.98 (0.68–1.41) | 1.19 (0.84–1.68) | 0.69 | 1.08 (0.69–1.67) | 1.08 (0.71–1.65) | 1.32 (0.87–2.00) | 0.22 |
| Otitis media | 1.33 (0.85–2.07) | 1.15 (0.73–1.82) | 1.30 (0.83–2.02) | 0.17 | 1.11 (0.65–1.89) | 0.99 (0.59–1.66) | 1.39 (0.82–2.35) | 0.17 |
| GI infections | 1.63 (0.80–3.34) | 1.31 (0.62–2.76) | 1.55 (0.75–3.20) | 0.33 | 1.89 (0.78–4.56) | 1.52 (0.65–3.54) | 1.54 (0.66–3.60) | 0.38 |
| LRTIs | 1.12 (0.71–1.76) | 1.54 (1.01–2.35)* | 1.01 (0.63–1.61) | 0.61 | 1.16 (0.65–2.09) | 1.68 (1.00–2.81)* | 1.18 (0.68–2.04) | 0.38 |
| All infectionsd | 1.19 (0.95–1.50) | 1.18 (0.94–1.48) | 1.19 (0.95–1.50) | 0.14 | 1.17 (0.88–1.55) | 1.19 (0.92–1.54) | 1.27 (0.98–1.66) | 0.04* |
| 12-Month follow-up | ||||||||
| URTIs | 0.93 (0.72–1.20) | 0.87 (0.67–1.13) | 1.12 (0.88–1.43) | 0.81 | 0.99 (0.71–1.36) | 0.96 (0.71–1.29) | 1.23 (0.92–1.65) | 0.29 |
| Otitis media | 1.05 (0.83–1.32) | 0.97 (0.76–1.22) | 0.94 (0.75–1.20) | 0.89 | 1.02 (0.77–1.35) | 0.89 (0.68–1.17) | 0.97 (0.73–1.28) | 0.89 |
| GI infections | 1.27 (0.86–1.88) | 1.22 (0.82–1.82) | 1.05 (0.69–1.58) | 0.81 | 1.53 (0.94–2.49) | 1.59 (1.01–2.49)* | 1.26 (0.78–2.04) | 0.29 |
| LRTIs | 0.88 (0.65–1.19) | 1.08 (0.81–1.45) | 0.96 (0.71–1.29) | 0.48 | 0.86 (0.57–1.28) | 1.10 (0.78–1.55) | 1.03 (0.72–1.48) | 0.36 |
| All infectionsd | 1.00 (0.87–1.15) | 0.99 (0.86–1.14) | 1.01 (0.88–1.16) | 0.67 | 1.02 (0.86–1.21) | 1.01 (0.86–1.19) | 1.08 (0.92–1.28) | 0.24 |
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.