Hypertension risk is associated with elevated concentrations of rare earth elements in serum.

ABSTRACT

BACKGROUND: Hypertension is a major contributor to cardiovascular morbidity and mortality, affecting over 17.1 million individuals worldwide. Environmental exposure such as toxic trace elements could be risk factors for hypertension, but the associations of toxic metal exposure with hypertension are not well understood. METHODS: We recruited 400 volunteers consisting of 200 patients with hypertension (cases) and 200 healthy individuals without hypertension (controls). In the case or control group, half of the subjects came from the rare earth mining (REM) areas and the other half from non-REM areas. Serum levels of 8 rare earth elements (REEs) and 13 non-REEs were determined. RESULTS: The concentrations of Ce and La were significant higher in the cases than in the controls in all comparisons. Serum concentrations of Mg, Mn, Dy, Ce and La were positively correlated with blood pressure, while those of concentrations K and Se were negatively correlated with blood pressure (p < 0.05). Compared with the lowest quartiles, participants in the highest quartiles of Sm, Gd, Dy, Yb, La and Ce had a 6.01-fold (95 % CI 2.28, 15.8), 3.29-fold (95 % CI 1.18, 9.16), 4.07-fold (95 % CI 1.51,10.9), 7.83-fold (95 % CI 2.78, 22.4), 20.00-fold (95 % CI 5.48-72.9) and 6.13-fold (95 % CI 2.13-17.6) increase in the probability of having hypertension respectively. Among all the detected metals, the univariate odds ratios (UORs) and adjusted odds ratios (AORs) of hypertension for highest vs. lowest quartile serum concentrations of Sm, Gd, Dy, Yb, La and Ce were significantly > 1 (p < 0.05), with the positive dose-response relationships observed between their serum levels and ORs associated with hypertension risk. CONCLUSIONS: Collectively, there appears to be a positive correlation between hypertension and environmental exposure to REEs, especially La and Ce. Further studies are warranted to investigate the underlying mechanisms responsible for the risk.