ABSTRACT
Objective The purpose of this study was to investigate the prevalence of vitamin D deficiency and hypertension in Henan rural residents, and to explore the association between vitamin D and risk of hypertension. Methods 2 013 Henan rural participants aged 18-80 years were recruited from a cross-sectional study. Logistic regression models and restricted cubic spline model were used to evaluate odds ratios (OR), 95% confidence intervals (95% CI) and dose-response relationship between vitamin D and risk of hypertension. Results In total population, the prevalence of hypertension was 40.34% (30.64% after age-standard), and the mean serum 25-(OH)D was (24.50 ± 16.18) ng/ml, and 53.95% of all participants were presenting vitamin D deficiency. Compared with non-hypertension, a lower level of serum 25-(OH)D was observed in people with hypertension. The prevalence of hypertension was 45.21% in vitamin D deficient group which was higher than in the vitamin D sufficient group (31.07%). Compared with the vitamin D sufficient group, the risk of hypertension was increase in the vitamin D deficient group (OR=1.59, 95% CI: 1.21-2.10), and the risk of hypertension decreased by 14% for every 10 ng/ml increase in serum 25-(OH) D levels. Moreover, an L-shaped relationship was observed between 25-(OH)D concentration and risk of hypertension. Conclusion Vitamin D deficiency is associated with risk of hypertension and there is an L-shaped relationship between 25-(OH)D concentration and risk of hypertension.