Association between the urinary nickel and the diastolic blood pressure in general population.

AIM:To investigate the association of the level of nickel and blood pressure (BP) level in a general population. METHODS:A total of 2201 participants were enrolled from the National Health and Nutrition Examination Surveys (NHANES) 2017-2018. Urinary nickel level was measured using inductively coupled-plasma mass spectrometry. Multivariable linear regressions were performed to explore the associations between nickel and systolic BP and diastolic BP. Restricted cubic splines were used to explore the nonlinearity. RESULTS:Per one-fold increase of nickel was associated with a 0.67-unit decrease of diastolic BP (β -0.67, 95 % confidence interval [CI] [-1.15, -0.18]; p = 0.007). Comparing with the lowest quartile, the highest quartile decreased 2.21-unit diastolic BP (β -2.21, 95 % CI [-3.84, -0.59]; p = 0.007). Restricted cubic spline confirmed the relationship was linear. Subgroup analysis found that the association was only significant in population without hypertension. CONCLUSIONS:The urinary nickel, as a long-term exposure biomarker, was associated with the diastolic BP in individuals without hypertension.