A Cochrane review [Abstract] 1 included 53 studies with a total of 91 791 subjects. Thirty-one trials, with sample sizes ranging from 70 to 36 282 participants, examined vitamin D (including 25-hydroxy vitamin D) with or without calcium in the prevention of fractures in community, nursing home or hospital inpatient populations. Twelve of these 31 trials had participants with a mean or median age of 80 years or over.22 smaller trials examined calcitriol or alfacalcidol (1-alphahydroxyvitamin D3), mostly with participants who had established osteoporosis. These trials were carried out in the setting of institutional referral clinics or hospitals.
Vitamin D alone, in the formats and doses tested, did not prevent hip fracture (RR 1.12, 95% CI 0.98 to 1.29; 11 studies, n= 27 693) or any new fracture (RR 1.03, 95% CI 0.96 to 1.11; 15 studies, n=28 271).
Vitamin D plus calcium resulted in a small reduction in hip fracture risk (RR 0.84, 95% CI 0.74 to 0.96; 9 studies, n=49 853). In low-risk populations (residents in the community: with an estimated 8 hip fractures per 1000 per year), this equates to 1 fewer hip fracture per 1000 older adults per year (95% CI 0 to 2). In high risk populations (residents in institutions: with an estimated 54 hip fractures per 1000 per year), this equates to 9 fewer hip fractures per 1000 older adults per year (95% CI 2 to 14). Vitamin D plus calcium also reduced the risk of new non-vertebral fractures (RR 0.86, 95% CI 0.78 to 0.96; 8 studies, n=10 380) and any type of fractures (RR 0.95, 95% CI 0.90 to 0.99; 10 studies, n=49 976). No statistically significant reduction in vertebral fractures was seen (RR 0.89, 95% CI 0.74 to 1.09; 4 studies, n=42 185). Mortality was not adversely affected by vitamin D plus calcium supplementation (RR 0.94, 95% CI 0.87 to 1.02; 6 studies, n=46 794). Most studies used 400 IU to 800 IU vitamin D3 daily with co-administration of 1000 mg calcium.
Two trials of alfacalcidol suggested that vertebral fractures may be prevented by taking alfacalcidol (RR 0.57, 95% CI 0.49 to 0.65; 2 studies, n=872), although the evidence did not suggest prevention of hip or non-vertebral fractures. The effect of calcitriol in fracture prevention was unclear, but it was associated with a statistically significant increase in risk of hypercalcaemia (RR 4.41, 95% CI 2.14 to 9.09; 4 studies, n=988).
Date of latest search: 2014-01-14
Primary/Secondary Keywords