A randomised, controlled comparison of different calcium and vitamin D supplementation regimens in elderly women after hip fracture: The Nottingham Neck of Femur (NoNOF) Study

Background: survivors of hip fracture are at 5- to 10-fold risk of a second hip fracture. There is little consensus about secondary prevention. Many are given calcium and vitamin D, but the evidence supporting this is circumstantial. Objective: to compare the effects of different calcium and vitamin D supplementation regimens on bone biochemical markers, bone mineral density and rate of falls in elderly women post-hip fracture. Design: randomised controlled trial. Setting: orthogeriatric rehabilitation ward. Methods: 150 previously independent elderly women, recruited following surgery for hip fracture, were assigned to receive a single injection of 300,000 units of vitamin D-2, injected vitamin D-2 plus 1 g/day oral calcium, 800 units/day oral vitamin D-3 plus 1 g/day calcium, or no treatment. Follow-up was one year, with measurement of 25-hydroxyvitamin D, parathyroid hormone, bone mineral density, and falls. Results: mean 25-hydroxyvitamin D increased and mean parathyroid hormone was suppressed in all the actively treated groups, more so in the group receiving combined oral vitamin D and calcium. Twenty per cent of participants injected with vitamin D were deficient in 25-hydroxyvitamin D a year later. Bone mineral density showed small but statistically significant differences of up to 4.6% between actively treated groups and placebo. Relative risk of falling in the groups supplemented with vitamin D was 0.48 ( 95% CI 0.26-0.90) compared with controls. Conclusion: Vitamin D supplementation, either orally or with injected vitamin D, suppresses parathyroid hormone, increases bone mineral density and reduces falls. Effects may be more marked with calcium co-supplementation. The 300,000 units of injected vitamin D may not last a whole year.