The association of multiple whole blood metals with hypertension prevalence and blood pressure among general Chinese adults

Abstract Background Epidemiological associations between multiple metals exposure and hypertension or blood pressure remain limited and inconclusive, especially for essential metals. This investigation intended to examine the individual and collective effects of multiple metals on hypertension and blood pressure in general Chinese adults. Methods Whole blood levels of 8 essential metals and 3 nonessential metals were determined via inductively coupled plasma mass spectrometry in 867 adults from Shiyan, China. Multivariable logistic/linear regression, restricted cubic spline regression, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) analyses were employed for exploring associations of individual metals or metal mixtures with hypertension prevalence and blood pressures. Results In total, 239 participants (29.5%) were identified as being hypertensive. Multivariable logistic regression models indicated that magnesium and iron were positively, while calcium was inversely, associated with hypertension prevalence, with odds ratios (95% CI) of 2.19 (1.36, 3.54), 2.70 (1.62, 4.50), and 0.58 (0.35, 0.94) respectively for extreme-tertile comparisons. Multivariable linear regression analysis demonstrated a positive association of iron with mean arterial pressure, showing a β (95% CI) of 2.70 (0.88, 4.51) for extreme-tertile comparison. Both WQS regression and BKMR models demonstrated a positive collective effect of eleven metals on hypertension, with magnesium and iron being the top contributors. The WQS regression model also showed a positive combined effect of metal mixtures on systolic blood pressure and mean arterial pressure. BKMR analyses further indicated that the eight essential metals presented a stronger association with hypertension or blood pressure than the three nonessential metals. Conclusion The present study demonstrated positive associations between multiple metals (individually or collectively) and hypertension or blood pressure among general Chinese adults, with essential metals magnesium and/or iron as major contributors. It may present useful epidemiological evidence on the pathogenesis and prevention of hypertension.