Alfacalcidol Reduces the Number of Fallers in a Community-Dwelling Elderly Population with a Minimum Calcium Intake of More Than 500 Mg Daily

Authors


  • This study was supported by TEVA Pharmaceuticals Industries Ltd., Israel, and University Hospital, Basel, Switzerland.

Address correspondence to Laurent C. Dukas, MD, MPH, Geriatric University Clinic, Hebelstrasse 10, Kantonsspital, 4031 Basel, Switzerland. E-mail: dukasl@uhbs.ch

Abstract

Objectives: To study the effect of alfacalcidol (1α(OH)D3) on fall risk in community-dwelling elderly men and women.

Design: Randomized, double-blind, placebo-controlled intervention trial.

Setting: Basel, Switzerland.

Participants: Three hundred seventy-eight community-dwelling elderly (191 women/187 men).

Intervention: Participants were randomly assigned to receive 1 μg of alfacalcidol or matched placebo daily for 36 weeks.

Measurements: Serum 25-hydoxyvitamin D3 (25(OH) D,1,25-dihydroxyvitamin D3 (D-hormone), and intact parathormone (iPTH) levels were measured using radioimmunoassay at baseline and every 12 weeks. Numbers of fallers and falls were assessed using a questionnaire during each study site visit. Dietary calcium intake was assessed at baseline using a food frequency questionnaire.

Results: At baseline, participants had, on average, normal vitamin D and D-hormone serum levels. Over 36 weeks, alfacalcidol treatment was associated with fewer fallers (odds ratio (OR)=0.69, 95% confidence interval (CI)=0.41–1.16) than placebo. In a post hoc subgroups analysis by medians of total calcium intake, this reduction reached significance in alfacalcidol-treated subjects with a total calcium intake of more than 512 mg/d (OR=0.45, 95% CI=0.21–0.97, P=.042) but not in those who consumed less than 512 mg/d (OR=1.00, 95% CI= 0.47–2.11, P=.998). Alfacalcidol treatment was also, independent of total calcium intake, associated with a significant 37.9% reduction in iPTH serum levels (P<.0001). No cases of clinically relevant hypercalcemia were observed.

Conclusion: Provided a minimal calcium intake of more than 512 mg/d, alfacalcidol treatment significantly and safely reduces number of fallers in an elderly community dwelling population.

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