Table 2.
Results from adjusted multiple linear regression models of diphtheria and tetanus antibody outcomes for single and combined metal exposures among the overall study population (n = 502)
| Water arsenic | Water manganese | Blood lead | ||||
|---|---|---|---|---|---|---|
| Change (%) (95% CI) | Change (%) (95% CI) | Change (%) (95% CI) | ||||
| Single elementa | Combinedb | Single elementa | Combinedb | Single elementa | Combinedb | |
| Diphtheria IgG antibody | ||||||
| Pregnancy | −3.4 (−7.2, 0.6) | −2.9 (− 7.0, 1.5) | −1.6 (−8.3, 5.5) | −1.1 (− 7.9, 6.2) | 4.7 (− 4.9, 15.3) | 4.1 (− 5.9, 15.2) |
| Toddlerhood | 1 (− 2.7, 4.9) | 0.8 (− 2.9, 4.8) | 2.7 (− 3.1, 8.8) | 2.7 (− 3.2, 8.9) | 5.9 (− 10.4, 25.2) | 4.6 (− 11.9, 24.1) |
| Early childhood | 1.7 (− 1.6, 5.1) | 2 (− 1.4, 5.5) | − 0.7 (− 5.8, 4.8) | −1.1 (− 6.4, 4.5) | −6.4 (− 20.4, 10.1) | −6.2 (− 20.5, 10.5) |
| Tetanus IgG antibody | ||||||
| Pregnancy | 0.5 (− 3.8, 5.0) | 2.6 (− 2.0, 7.5) | 5.1 (− 2.5, 13.3) | 5.4 (−2.3, 13.6) | 10.2 (− 0.6, 22.1) | 13.3 (1.7, 26.2) |
| Toddlerhood | − 0.8 (− 4.7, 3.3) | −1 (− 4.9, 3.1) | − 2.7 (− 8.5, 3.5) | −3.9 (− 9.7, 2.3) | 1.6 (− 15.5, 22.2) | 3.2 (− 14.1, 24.1) |
| Early childhood | −0.1 (− 3.6, 3.6) | 0.4 (− 3.2, 4.1) | − 0.6 (− 6.1, 5.2) | −1.5 (− 7.1, 4.4) | 2 (− 14.3, 21.4) | 3.4 (− 13.2, 23.2) |
Note: Missing values of arsenic, manganese, and lead were estimated by multiple imputation. All models are adjusted for maternal education, breastfeeding duration, and child sex. Outcomes are interpreted as percent change in median antibody concentration per doubling in given exposure
a Models include includes single metal exposure category (arsenic, manganese, or lead) at all three periods of exposure
b Model includes all metal exposure categories (arsenic, manganese, and lead) at all three periods of exposure