The response of elderly veterans to daily vitamin D3 supplementation of 2,000 IU: a pilot efficacy study

Abstract

Objectives: To determine the prevalence of hypovitaminosis D (serum 25-hydroxyvitamin D<32 ng/mL; HVD) in a population of elderly veterans and conduct a preliminary assessment of the efficacy of supplementation with cholecalciferol in correcting HVD.

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

Setting: Geriatric clinic at the Bruce W. Carter Veterans Affairs Medical Center, Miami, Florida.

Participants: Veterans aged 70 and older.

Intervention: Oral cholecalciferol 2,000 IU daily or placebo for 6 months.

Measurements: Serum calcium, 25-hydroxyvitamin D, parathyroid hormone, and 24-hour urinary calcium.

Results: Of the 34 participants who completed the study, 62% had HVD at baseline. In the treatment group, mean serum 25-hydroxyvitamin D level rose from 28.4±7.9 ng/mL at baseline to 42.7±10.5 ng/mL at the end of the trial, but levels remained less than 32 ng/mL in three of 17 (18%) of the participants. In the placebo group, the baseline level of 27.7±8.3 ng/mL remained unchanged (28.8±8.7 ng/mL). Supplementation did not alter serum or urinary calcium levels and did not result in any adverse events.

Conclusion: These initial observations suggest that, in older veterans, cholecalciferol 2,000 IU daily for 6 months is generally safe and corrects HVD in most but not all individuals.