Objective: To determine whether vitamin D supplementation decreases the incidence of hip fractures and other peripheral bone fractures.
Design: Prospective, double-blind trial.
Setting: Community setting (Amsterdam and surrounding area).
Patients: 2578 persons (1916 women, 662 men) 70 years of age and older (mean age ±SD, 80 ± 6 years) living independently, in apartments for elderly persons, or in homes for elderly persons.
Intervention: Participants were randomly assigned to receive either vitamin D3, 400 IU in one tablet daily, or placebo for a maximum of 3.5 years.
Measurements: Dietary calcium intake and serum 25-hydroxyvitamin D [25(OH)D] were estimated in a subset of participants. During follow-up, attention was concentrated on hip fractures and other peripheral fractures. The maximal follow-up period was 4 years. The results were evaluated by survival analysis.
Results: Mean dietary calcium intake from dairy products was 868 mg/d. Mean serum 25(OH)D concentration in the third year of the study was 23 nmol/L in the placebo group and 60 nmol/L in the vitamin D group. Median follow-up was 3.5 years, and total follow-up was 8450 patient-years. During follow-up, 306 persons in the placebo group and 282 persons in the vitamin D group died (P = 0.20). Hip fractures occurred in 48 persons in the placebo group and 58 persons in the vitamin D group (P = 0.39, intention-to-treat analysis). Other peripheral fractures occurred in 74 persons in the placebo group and 77 persons in the vitamin D group (P = 0.86).
Conclusion: Our results do not show a decrease in the incidence of hip fractures and other peripheral fractures in Dutch elderly persons after vitamin D supplementation.