P4.6 Pulsatile and Steady Blood Pressure Components in Relation to Environmental Lead Exposure in the National Health and Nutrition Examination Survey 2003–2010

In view of the declining environmental lead exposure in the US, we analyzed the National Health and Nutrition Examination Survey (2003–2010) for association of pulsatile and steady BP components and hypertension (HT) with blood lead (BPb). The 12,725 participants included 21.2% Blacks, 20.5% Hispanics, 58.4% Whites, and 48.7% women. Blacks compared with non-Blacks had higher SBP, DBP, and mean arterial pressure (MAP) (126.5 vs. 123.9; 71.9 vs. 69.6; and 90.1 vs. 87.7mmHg, respectively) and higher HT prevalence (44.7 vs. 36.8%). SBP, DBP and MAP (123.3 vs. 125.5; 68.9 vs. 71.2; and 87.1 vs. 89.3mmHg) were lower in women than men with no significant sex difference in PP and HT prevalence ( P ≥0.11). BPb was lower in Whites than non-Whites (1.46 vs. 1.57µg/dL) and in women than men (1.25 vs. 1.80µg/dL). In multivariable analyses of all participants, BPb doubling was associated with higher ( P ≤0.0007) SBP, DBP and MAP (0.76 [CI, 0.38–1.13]; 0.43 [0.18–0.68]; and 0.54 [0.29–0.79]mmHg, respectively) with no change in PP ( P = 0.063) or the odds of HT ( P = 0.11). Associations with BPb were nonsignificant ( P ≥0.09) for SBP in women and for DBP and MAP in non-Whites. Among men, SBP increased with BPb ( P ≤0.060) with effect sizes associated with BPb doubling ranging from +0.65mmHg in Whites to +1.61mmHg in Blacks. For SBP and PP, interactions of ethnicity and sex with BPb were all significant ( P ≤0.027). In conclusion, small and inconsistent effect sizes in the associations of BP with BPb likely exclude current environmental lead exposure as a major HT cause in the US.