Table 2.
Continuous blood lead levels (BLLs) or an elevated BLL (EBLL) ≥5 µg/dL after correcting for risk factors and other covariates in full multiple regression model analysis—the 1999 to 2010 NHANES.
| Independent Variable | BLL (in µg/dL) | EBLL (≥5 µg/dL) | ||||
|---|---|---|---|---|---|---|
| B Coeff. (β) | 95% CI | p-Value | Odds Ratio | 95% CI | p-Value | |
| Age in Years | ||||||
| 4–5 years | Reference | – | – | Reference | – | – |
| 3 years | +0.19 per unit (+0.105) | +0.10 to +0.28 | <0.001 ** | 1.7 | 0.92 to 3.2 | 0.089 |
| 2 years | 2.7 | 1.5 to 4.9 | 0.001 ** | |||
| 1 year | 3.4 | 1.7 to 6.9 | 0.001 ** | |||
| Anemia | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | +0.29 (+0.031) | −0.03 to +0.61 | 0.074 | 2.2 | 1.3 to 4.0 | 0.005 ** |
| Binary Gender | ||||||
| Female | Reference | – | – | Reference | – | – |
| Male | +0.11 (+0.025) | −0.04 to +0.25 | 0.151 | 1.3 | 0.90 to 1.8 | 0.178 |
| Bodyweight (in kg) | ||||||
| Continuous (scaled) | −0.02 per unit (−0.050) | −0.05 to 0.00 | 0.051 * | 0.98 | 0.92 to 1.1 | 0.554 |
| Health Insurance Coverage | ||||||
| Yes | Reference | – | – | Reference | – | – |
| No | +0.26 (+0.038) | +0.01 to +0.52 | 0.039 * | 1.3 | 0.77 to 2.2 | 0.332 |
| Household Income Level | ||||||
| Middle to upper class | Reference | – | – | Reference | – | – |
| Low income | +0.28 per unit (+0.109) | +0.17 to +0.39 | <0.001 ** | 2.2 | 1.4 to 3.7 | 0.002 ** |
| Poverty | 2.5 | 1.5 to 4.2 | 0.001 ** | |||
| Indoor Household Smoking | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | +0.42 (+0.072) | +0.21 to +0.62 | <0.001 ** | 1.8 | 1.2 to 2.7 | 0.002 ** |
| Low Birthweight | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | +0.05 (+0.007) | −0.21 to +0.31 | 0.681 | 1.3 | 0.79 to 2.3 | 0.285 |
| Medicaid/CHIP Enrollment | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | +0.12 (+0.027) | −0.07 to +0.31 | 0.204 | 1.0 | 0.70 to 1.5 | 0.859 |
| Primary Guardian Education | ||||||
| Some college or higher | Reference | – | – | Reference | – | – |
| 12th grade or GED | +0.11 per unit (+0.044) | +0.01 to +0.21 | 0.026 * | 1.0 | 0.65 to 1.6 | 0.986 |
| Less than 12th grade or GED | 1.3 | 0.86 to 2.0 | 0.210 | |||
| Race/Ethnicity | ||||||
| Hispanic | Reference | – | – | Reference | – | – |
| NH White | +0.46 per unit (+0.161) | +0.36 to +0.56 | <0.001 ** | 1.5 | 0.97 to 2.4 | 0.070 |
| NH Black | 3.5 | 2.2 to 5.5 | <0.001 ** | |||
| Survey Years | ||||||
| 1999 to 2002 | Reference | – | – | Reference | – | – |
| 2003 to 2006 | −0.40 per unit (−0.151) | −0.49 to −0.31 | <0.001 ** | 0.42 | 0.29 to 0.62 | <0.001 ** |
| 2007 to 2010 | 0.31 | 0.20 to 0.48 | <0.001 ** | |||
| Water Treatment Devices Used | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | −0.21 (−0.043) | −0.38 to −0.04 | 0.015 * | 0.83 | 0.52 to 1.3 | 0.420 |
| WIC Enrollment | ||||||
| No | Reference | – | – | Reference | – | – |
| Yes | −0.01 (−0.003) | −0.19 to +0.16 | 0.889 | 1.0 | 0.70 to 1.5 | 0.908 |
| Year Housing Built | ||||||
| 1978 to present | Reference | – | – | Reference | – | – |
| 1950 to 1977 | +0.61 per unit (+0.226) | +0.52 to +0.70 | <0.001 ** | 1.9 | 1.2 to 2.9 | 0.007 ** |
| Before 1950 | 7.1 | 4.6 to 10.8 | <0.001 ** | |||
Statistical significance: * p-value equal to 5% or less; ** p-value equal to 1% or less.