Disturbed calcium metabolism in subjects with elevated diastolic blood pressure

Summary Essential hypertension has been associated with disturbed calcium metabolism, but the available data are controversial. We measured parameters of calcium metabolism in groups of untreated male subjects (n = 78) with elevated diastolic blood pressure (101 ± 6 mmHg, mean ± SD) and age-matched male subjects (n=79) with low diastolic blood pressure (62 ± 4 mmHg). The participants of the study were drawn from a random population sample. Subjects with high diastolic blood pressure had significantly higher carboxy-terminal parathyroid hormone (PTH) plasma concentrations than controls with low diastolic blood pressure (median 114 vs. 43 pmol/l, P < 0.01). The 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations were comparable in both groups. Individuals with high diastolic blood pressure had significantly lower total serum calcium (2.41 ± 0.10 vs. 2.47 ± 0.10 mmol/l, mean ± SD; P < 0.01). PTH concentrations were correlated with diastolic pressure (r = –0.39, P < 0.001). The data are compatible with increased parathyroid activity despite unchanged concentrations of vitamin D metabolites in human hypertension.Abbreviations PTH parathyroid hormone - C-PTH carboxy-terminal parathyroid hormone - 1,25(OH)₂D 1,25-di-hydroxyvitamin D - 25(OH)D 25-hydroxyvitamin D