Serum 25-hydroxyvitamin D and parathyroid hormone levels in relation to blood pressure in a cross-sectional study in older Chinese men.

Vitamin D status, parathyroid hormone (PTH) level and their associations with blood pressure in Chinese population are unknown. This study examined these associations in older Chinese men. Blood pressure, serum 25-hydroxyvitamin D (25OHD) and PTH was measured in 939 community-dwelling Chinese men aged 65 years and older. Linear regression analyses were performed with adjustments for age, body mass index, education, season of measurement, medication use, self-reported history of stroke and Parkinson's disease, and other lifestyle factors. In either crude or adjusted models, serum 25OHD was not associated with blood pressure, whereas increasing PTH levels was associated with higher blood pressure. Men in the highest quartile of serum PTH level had a mean difference of 3.4 mm Hg and 2.8 mm Hg higher in as systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively, than men in the lowest quartile of serum PTH level (P(trend)=0.019 for SBP and <0.001 for DBP). In conclusion, the findings support an association between serum PTH and blood pressure, but not for serum 25OHD in older Chinese men whose vitamin D status is optimal. The lack of association between serum 25OHD and blood pressure may possibly because of the relatively high serum 25OHD levels of the study sample.