A Randomized Double-Blinded Superiority Trial to Compare the Efficacy of Vitamin D3 and Calcium versus placebo in Prevention of Hip Fractures in Elderly Women

Background and Aim: The role of vitamin D plus calcium to protect against hip fracture in postmenopausal women remains controversial. Two major studies on this subject presented diverse outcomes; they implemented different doses of Vitamin D and Calcium, and they studied different populations. One study found evidence that Calcium plus Vitamin D do protect against fractures; the second study failed to demonstrate such protection. The aim of the present study is to test the hypothesis that a higher dose of vitamin D plus calcium is effective in reducing hip fractures in non-osteoporotic elderly women when compared to placebo. Methods: This will be a randomized, double-blinded superiority, multicenter trial involving three centers in Sao Paulo, Lima and Mexico City. After a three-month run-in period, 7176 participants will receive Calcium + Vitamin D or Placebo. The primary outcome is the occurrence of hip fractures assessed by the pelvic radiographic image; secondary outcomes include other fractures, the variation of Bone Mass Density, and the adverse effects rate. Conclusion: There is an increase in morbidity, mortality, and costs resulting from hip fractures since it is an important risk fact following accidents. A possible lack of benefit inside the active group drives more attention to an eventual over-prescription of those substances. Therefore, further studies including a phase II trial with different exclusion criteria could be desirable to confirm these findings and help to reduce the incidence of hip fractures.. Key-Words: Hip Fractures, Bone Loss, Postmenopausal, Vitamin D Deficiency, Bone Density, Calcium, Dietary, Osteopenia, Postmenopausal Osteoporosis, Design, Research Protocol, Clinical Research.