The rationale for using vitamin D in older people to prevent fractures exists beyond doubt but both the dose of vitamin D and the need for co-supplementation with calcium are not exactly clear. Conflicting results have been reported from various randomized trials examining the effect of vitamin D supplementation (with or without calcium) on the incidence of fractures.
The DIPART (Vitamin D Individual Patient Analysis of Randomized Trials) Group has recently published an analysis using pooled data from 68,500 participants from seven major randomized, vitamin D fracture trials in the USA and Europe . The criteria for inclusion of a study in their analysis included that it must have at least 1000 participants, have at least one interventional arm using vitamin D, and have fracture as an outcome. Logistic regression and the Cox’s hazards model were used for data analysis to identify significant interactions. The results of individual patient data analysis showed that vitamin D alone in doses of 10–20 µg (400–800 IU) was not effective in preventing fractures. On the other hand, vitamin D given with calcium showed a reduced overall risk of fracture (hazard ratio 0.92, 95% confidence interval 0.86–0.99; [i]p[/i] = 0.025).
Senior Consultant, Department of Obstetrics & Gynecology, PGIMER, Chandigarh, India
DIPART (Vitamin D Individual Patient Analysis of Randomized Trials) Group. Patient level pooled analysis of 68 500 patients from seven major vitamin D fracture trials in US and Europe. BMJ 2010;340:b5463. Published online January 12, 2010.
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