Re: Should vitamin D supplements be recommended to healthy elderly people?
We highly appreciate the response provided by Professor Meyer et al to our previous comment (1). However, in our opinion this new explanation doesn’t focus on the most relevant issue: is there good-quality evidence that vitamin D plus calcium reduce sound outcomes for the general elderly population?
Among the several references cited by the authors on nutritional recommendations, 2011 IOM guideline is probably the most significant (2). Its recommendation (600-800 IU of vitamin D) is based mainly on bone health criteria, a concept that comes from the 2007 Evidence Report on vitamin D published by the American Agency for Healthcare Research and Quality. In the conclusion of this report (3) it can be read that “There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults)”. Therefore, even if the recommendation of vitamin D supplements was carefully followed, a decrease in overall fractures cannot be taken for granted (and especially if we consider the outcomes on the main target, that is, hip fractures).
On the other hand, “a modestly decreased risk of all-cause mortality (from 11.4% to 11.0%; RR 0.94, 95% CI 0.91-0.98)” is claimed based on the Bjelakovic et al Cochrane review (4). However, we should not miss out the authors’ remarks on the quality of evidence of this statement: “We found evidence suggesting that vitamin D3 may significantly benefit survival of elderly ambulatory participants living in institutional care who were likely to be vitamin D deficient with significant risk of falls and fractures, when we disregard the risks of attrition bias and outcome reporting bias. However, if these bias risks are considered, we do not yet know whether vitamin D3 affects mortality”.
Thus, according to the above-mentioned considerations, we maintain our suggestion of thinking twice before recommending a vitamin D plus calcium supplement to healthy people.
(2) Ross AC, Manson JE, Abrams SA, Aloia JF, Brannon PM, Clinton SK, et al. The 2011 report on dietary reference intakes for calcium and vitamin D from the Institute of Medicine: what clinicians need to know. J Clin Endocrinol Metab2011;96:53-8.
(3) Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, et al. 2007 Effectiveness and safety of vitamin D in relation to bone health. Evidence Report/Technology Assessment no. 158 (prepared by the University of Ottawa Evidence-based Practice Center. AHRQ Publication no. 07-E013. Rockville, MD: Agency for Healthcare Research and Quality.
(4) Bjelakovic G, Gluud LL, Nikolova D, Whitfield K, Wetterslev J, Simonetti RG, et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database Syst Rev 2014;1:CD007470.
Competing interests: No competing interests