CRD summary

This review evaluated the effectiveness of vitamin D in preventing falls in older people. The authors concluded that vitamin D supplementation reduced the risk of falls by more than 20%. This seems a well-conducted review and the conclusions are likely to be reliable.

Authors' objectives

To assess the effectiveness of vitamin D in preventing falls in older people.

Searching

MEDLINE (1960 to February 2004), the Cochrane Controlled Trials Register (1960 to February 2004) and EMBASE (1991 to February 2004) were searched with no language restrictions; the search terms were reported. Reference lists and conference abstracts of the American Society for Bone and Mineral Research (1995 to 2002) were also searched, and experts were contacted.

Study selection

Assessment of study quality

The criteria used to assess study quality were randomisation, allocation concealment, blinding and withdrawals. The authors did not state how the papers were assessed for quality, or how many reviewers performed the quality assessment.

Data extraction

Three reviewers independently extracted the data. The data abstracted for each study were the odds ratio (OR) and the associated 95% confidence interval (CI).

Methods of synthesis

Results of the review

Ten RCTs in total were included. Of these, 5 RCTs met the inclusion criteria and were included in the main analysis (1,237 participants); the 5 RCTs that did not meet the inclusion criteria were included in the sensitivity analysis. A total of 10,0001 participants were included in the secondary analyses.

Of the 5 RCTs included in the main analyses, four reported the method of randomisation and allocation concealment, and the results were analysed on an intention-to-treat basis. Three were blinded to treatment allocation. The reasons for drop-out were balanced between the treatment and control groups, and ranged from 7 to 28% across the trials.

There was a statistically significant decrease of 22% in the risk of having a fall in older people taking vitamin D in comparison with participants receiving calcium or placebo (5 RCTs) The corrected OR was 0.78 (95% CI: 0.64, 0.92), with an associated NNT of 15 (95% CI: 8, 53). The authors reported that there was no statistically significant heterogeneity between these studies.

When the additional 5 studies that did not meet the inclusion criteria were included in the analysis, there was a statistically significant decrease of 13% in the risk of having a fall in older people taking vitamin D in comparison with the control. The corrected OR was 0.87 (95% CI: 0.80, 0.96).

The results of several subgroup analyses were reported in the review. The authors reported that there was no evidence of publication bias.

Authors' conclusions

Vitamin D supplementation appeared to reduce the risk of falls among ambulatory and institutionalised older people with stable health by more than 20%.

CRD commentary

The review question and the inclusion criteria were clearly defined in terms of the interventions, participants, outcomes and study designs. The authors searched relevant databases without language restrictions, and also attempted to obtain both published and unpublished studies. The data extraction was carried out in duplicate. The authors did not report whether the study selection process was duplicated to reduce selection bias, although they did perform sensitivity analyses using the excluded studies. The authors used appropriate summary measures and a meta-analysis. This seems a well-conducted review and the conclusions are likely to be reliable.

Implications of the review for practice and research

Practice: The authors stated that vitamin D supplementation should be considered in the elderly.

Research: The authors suggested further studies in men and for cholecalciferol are required. The impact of calcium and its dose on fall outcomes needs to be investigated.

Funding

Harvard/Harford Foundation; Charles A King Trust Fellowship Award; Irene and Frederick Stare Nutrition and Education Fund; Swiss Foundation for Nutrition Research; International Foundation for the Promotion of Nutrition Research and Nutrition Education.

Bibliographic details

Bischoff-Ferrari H A, Dawson-Hughes B, Willett W C, Staehelin H B, Bazemore M G, Zee R Y, Wong J B. Effect of vitamin D on falls: a meta-analysis. JAMA 2004; 291(16): 1999-2006. [PubMed: 15113819]

Original Paper URL

http://jama.ama-assn.org/

Other publications of related interest

These additional published commentaries may also be of interest. Monaghan H. Review: prophylactic use of vitamin D reduces falls in older people. Evid Based Nurs 2004;7:119. Johnson BE. Review: prophylactic use of vitamin D reduces falls in older persons. ACP J Club 2004;141:66. Johnson BE. Review: prophylactic use of vitamin D reduces falls in older persons. Evid Based Med 2004;9:169.

Indexing Status

Subject indexing assigned by NLM

MeSH

Accidental Falls /prevention & control /statistics & numerical data; Aged; Humans; Randomized Controlled Trials as Topic; Vitamin D /therapeutic use

AccessionNumber

12004008298

Database entry date

30/09/2005

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.