ArticlesVitamin D supplementation and falls: a trial sequential meta-analysis
Introduction
Vitamin D supplementation has long been advocated for maintaining and improving musculoskeletal health.1 More recently, the association between vitamin D insufficiency and a variety of non-skeletal disorders has led to calls for broader use of vitamin D supplements.2, 3 However, findings from several recent systematic reviews and meta-analyses of randomised controlled trials do not support such recommendations. Vitamin D supplementation (without coadministered calcium supplements) has no clinically relevant effect on bone mineral density,4 no effect on total fracture or hip fracture,5, 6 and no effect on a broad range of non-skeletal endpoints.7, 8 One of the remaining recommendations for vitamin D supplementation is in the prevention of falls, even though recent meta-analyses on this topic have reported conflicting results.9, 10, 11, 12, 13
Recently, we reported the results of a trial sequential meta-analysis of vitamin D supplements on fracture, cardiovascular events, cancer, and mortality.8 Trial sequential analysis complements traditional meta-analysis by permitting an estimation of the point at which the body of evidence is sufficiently large and consistent to make further trials futile, because of the low probability that they will affect the results of the existing meta-analysis.14, 15 This approach is similar to the early termination of a clinical trial when interim analyses suggest that continuing the trial is highly unlikely to alter the interim result, although there is more certainty that later data will be similar to earlier data for a trial than in a trial sequential analysis. Using this technique, we concluded that existing trials reliably show that vitamin D supplementation, with or without calcium, does not produce clinically relevant effects on fracture, cardiovascular events, cancer, and mortality in unselected community-dwelling individuals, and that future trials with similar designs were unlikely to change these conclusions.8 Here, we extend these trial sequential analyses to the most recent meta-analyses of vitamin D supplementation on falls.
Section snippets
Search strategy
We searched PubMed in January, 2014, with the terms “vitamin D”, “systematic review”, and “meta-analysis” and identified ten trial-level meta-analyses of the effects of supplementation with vitamin D, with or without calcium, on falls published since January, 2009 (appendix).9, 10, 11, 12, 13, 16, 17, 18, 19, 20 We also reviewed the recent report on vitamin D intake by the Institute of Medicine.21 We identified all randomised trials included in any of these meta-analyses that studied vitamin D
Results
We obtained falls data from 20 trials (table 1).22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 The risk of bias in the trials is described in the appendix. All trials were randomised, 17 were double-blind, placebo-controlled trials,22, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 40, 41 13 described the random sequence generation explicitly,22, 23, 24, 27, 28, 31, 32, 34, 35, 37, 39, 40, 41 and 14 described the methods of allocation concealment.22, 23,
Discussion
Supplementation with vitamin D, with or without calcium, had no effect on falls in traditional meta-analysis. Trial sequential analysis suggests that vitamin D supplementation, with or without calcium, does not decrease falls by 15% or more, and that results from similar future trials are unlikely to alter this finding. A sensitivity analysis suggests that similar conclusions apply when considering a 10% risk reduction. The results of the traditional meta-analyses and the trial sequential
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2020, BoneCitation Excerpt :The calcium dose ranged between 360-1,200 mg/d. The outcome of interest was the number of falls [18,20–24,26] and/or the number of patients suffering from one or more falls (number of fallers) [19–21,23–25]. The duration of the intervention in the included studies extended from 1 to 60 months [19,20,22–26] (see Table 1 [18–30], Appendix 1 [18–30]).
Clinical practice guideline for management of osteoporosis and fracture prevention in Canada: 2023 Update
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