Serum 25-hydroxyvitamin D3, parathyroid hormone and blood pressure in an elderly cohort from Germany: a cross-sectional study

Cross-sectional data of 132 non-institutionalised subjects (90 women and 42 men, aged 66- 96 years) from Giessen, Germany, were analysed. Serum 25(OH)D3 and iPTH were measured by an electrochemiluminescence immunoassay and BP was determined with a sphygmomanometer. We performed univariate and multiple regression analyses to examine the influence of 25(OH)D3 and iPTH on BP with adjustments for age, body composition and lifestyle factors.While iPTH had no impact on BP, 25(OH)D3 was negatively associated with systolic BP in men, but not in women. After splitting the cohort into antihypertensive medication users and non-users, 25(OH)D3 was a significant predictor for systolic and diastolic BP only in men not receiving antihypertensive medicine, even after multiple adjustment. Adjustment for 25(OH)D3 resulted in an inverse association of iPTH with diastolic BP also only in men without intake of antihypertensive medicine.In elderly men without vitamin D deficiency and not taking antihypertensive medicine, 25(OH)D3 may be a negative determinant of BP, independent of iPTH, body composition and lifestyle factors. Furthermore, iPTH may be an independent negative determinant of diastolic BP in men not taking antihypertensive medicine.Vitamin D may play an important role in blood pressure (BP) regulation. Numerous cells within the human body are able to express the vitamin D receptor, including cardiomyocytes, vascular smooth muscle cells, endothelial cells and renin-producing juxtaglomerular cells [1-3].At present, results regarding the impact of vitamin D status, determined by circulating 25-hydroxyvitamin D concentrations [25(OH)D], on BP or hypertension are inconsistent. While some studies reported a negative association between vitamin D and BP [4-11], other studies failed to confirm a relationship [12-18] or even reported a positive association [19]. Parathyroid hormone (PTH), which rises in case of a low vitamin D status, may also affect BP [17,18,20-22], but studies are