Independent associations of serum concentrations of 25-hydroxyvitamin D and parathyroid hormone with blood pressure among US adults

Abstract
Vitamin D deficiency or high levels of parathyroid hormone (PTH) appear to be emerging risk factors for hypertension. This study examined whether serum concentrations of 25-hydroxyvitamin D [25(OH)D] and PTH were independently associated with blood pressure and the presence of hypertension or prehypertension among the United States adults. Cross-sectional data from 7228 participants (aged ≥20 years) in the 2003–2006 National Health and Nutrition Examination Survey were analyzed. The least square means and the regression coefficients of systolic blood pressure, diastolic blood pressure, and pulse pressure across quintiles of serum 25(OH)D and PTH were estimated by conducting multiple linear regression analyses. The adjusted prevalence ratios with 95% confidence intervals for hypertension and prehypertension were estimated using the log-binomial method. Among participants not taking blood pressure medications (n = 5414), the mean age- and sex-adjusted systolic and diastolic blood pressure decreased linearly across quintiles of serum 25(OH)D but increased linearly across quintiles of serum PTH (P Conclusion Serum concentrations of 25(OH)D and PTH were independently associated with blood pressure and with the presence of hypertension or prehypertension among the United States adults, though casual relationships remain to be elucidated.