Table 6.
Study II: PFOA and pregnancy outcome based on birth records linked to the C8 Health Project: association of PFOA with pregnancy-induced hypertension, Mid-Ohio Valley, 1990–2004.
| Estimated PFOA | Live births (n) | Cases (n) | Crude OR | Adjusteda OR (95% CI) | ||||
|---|---|---|---|---|---|---|---|---|
| Uncalibrated | ||||||||
| IQR(lnPFOA)b increase | 3,905 | 250 | 1.08 | 1.05 (0.85, 1.31) | ||||
| 100-ng/mL increase | 3,905 | 250 | 0.98 | 1.01 (0.91, 1.12) | ||||
| < 40th percentile (3.9 to < 8.9 ng/mL) | 1,632 | 96 | 1.0 | 1.0 | ||||
| 40th to < 60th percentile (8.9 to < 21.8 ng/mL) | 778 | 52 | 1.1 | 1.0 (0.7, 1.4) | ||||
| 60th to < 80th percentile (21.8 to 83.3 ng/mL) | 736 | 52 | 1.2 | 1.1 (0.7, 1.5) | ||||
| ≥ 80th percentile (83.3 to 921.3 ng/mL) | 759 | 50 | 1.1 | 1.1 (0.8, 1.5) | ||||
| Bayesian calibration | ||||||||
| IQR(lnPFOA)c increase | 3,905 | 250 | 1.11 | 1.13 (0.92, 1.37) | ||||
| 100-ng/mL increase | 3,905 | 250 | 0.92 | 0.97 (0.85, 1.11) | ||||
| < 40th percentile (3.9 to < 8.9 ng/mL) | 1,635 | 88 | 1.0 | 1.0 | ||||
| 40 to < 60th percentile (8.9 to < 19.6 ng/mL) | 757 | 46 | 1.1 | 1.0 (0.7, 1.4) | ||||
| 60 to < 80th percentile (19.6 to 53.1 ng/mL) | 735 | 67 | 1.7 | 1.5 (1.1, 2.1) | ||||
| ≥ 80th percentile (53.1 to 1897.0 ng/mL) | 778 | 49 | 1.2 | 1.2 (0.8, 1.7) | ||||
| Traditional calibration | ||||||||
| IQR(lnPFOA)d increase | 3,905 | 250 | 1.01 | 1.03 (0.87, 1.22) | ||||
| 100-ng/mL increase | 3,905 | 250 | 0.83 | 0.89 (0.75, 1.06) | ||||
| < 40th percentile (0.05 to < 11.4 ng/mL) | 1,628 | 82 | 1.0 | 1.0 | ||||
| 40th to < 60th percentile (11.4 to < 21.0 ng/mL) | 759 | 63 | 1.6 | 1.5 (1.1, 2.2) | ||||
| 60th to < 80th percentile (21.0 to 49.0 ng/mL) | 729 | 62 | 1.7 | 1.5 (1.1, 2.2) | ||||
| ≥ 80th percentile (49.0 to 2468.4 ng/mL) | 789 | 43 | 1.1 | 1.1 (0.8, 1.7) | ||||
| aAdjusted for maternal age, education, parity, smoking status, exposure year, state of residence. bEffect estimates represent the change in outcome for a shift from the 25th percentile to the 75th percentile in estimated PFOA serum levels [IQR(lnPFOA) = 2.39]. cEffect estimates represent the change in outcome for a shift from the 25th percentile to the 75th percentile in estimated PFOA serum levels [IQR(lnPFOA) = 1.92]. dEffect estimates represent the change in outcome for a shift from the 25th percentile to the 75th percentile in estimated PFOA serum levels [IQR(lnPFOA) = 1.61]. | ||||||||