No significant effect of calcium and vitamin D supplementation on blood pressure and calcium metabolism in elderly Chinese.

To examine the effects of calcium and vitamin D supplementation on blood pressure and calcium metabolism, we conducted a randomized, double-blind, 2 x 2 factorial intervention study in 58 institutionalized elderly persons. The subjects were randomly allocated into four groups to receive: (1) calcium (800 mg/day) + vitamin D3 placebo, (2) vitamin D3 (5 micrograms/day) + calcium placebo, (3) calcium + vitamin D3, or (4) placebo treatment. Blood pressure was measured and a 24-h urine specimen and an 8-h fasting blood sample were collected at the time of recruitment before treatment and after 2 and 11 weeks of treatment. The changes in urinary calcium levels and plasma vitamin D concentrations were highly correlated with the corresponding treatments in each group, indicating good compliance. Mean systolic blood pressure decreased slightly during intervention in the group given calcium supplements, but increased slightly in the group given calcium + vitamin D. The data suggest that oral supplements of 800 mg calcium or 5 micrograms vitamin D daily produce no significant effect on blood pressure in the elderly in 11 weeks.

RCT Entities:   Population Interventions Outcomes