33
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Effects of vitamin D supplementation on bone density in healthy children: systematic review and meta-analysis

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Objective To determine the effectiveness of vitamin D supplementation for improving bone mineral density in children and adolescents and if effects vary with factors such as vitamin D dose and vitamin D status.

          Design Systematic review and meta-analysis.

          Data sources Cochrane Central Register of Controlled Trials, Medline (1966 to present), Embase (1980 to present), CINAHL (1982 to present), AMED (1985 to present), and ISI Web of Science (1945 to present), last updated on 9 August 2009, and hand searching of conference abstracts from key journals.

          Study selection Placebo controlled randomised controlled trials of vitamin D supplementation for at least three months in healthy children and adolescents (aged 1 month to <20 years) with bone density outcomes. Two authors independently assessed references for inclusion and study quality and extracted data.

          Data synthesis Standardised mean differences of the percentage change from baseline in bone mineral density of the forearm, hip, and lumbar spine and total body bone mineral content in treatment and control groups. Subgroup analyses were carried out by sex, pubertal stage, dose of vitamin D, and baseline serum vitamin D concentration. Compliance and allocation concealment were also considered as possible sources of heterogeneity.

          Results From 1653 potential references, six studies, totalling 343 participants receiving placebo and 541 receiving vitamin D, contributed data to meta-analyses. Vitamin D supplementation had no statistically significant effects on total body bone mineral content or on bone mineral density of the hip or forearm. There was a trend to a small effect on lumbar spine bone mineral density (standardised mean difference 0.15, 95% confidence interval −0.01 to 0.31; P=0.07). Effects were similar in studies of participants with high compared with low serum vitamin D levels, although there was a trend towards a larger effect with low vitamin D for total body bone mineral content (P=0.09 for difference). In studies with low serum vitamin D, significant effects on total body bone mineral content and lumbar spine bone mineral density were roughly equivalent to a 2.6% and 1.7% percentage point greater change from baseline in the supplemented group.

          Conclusions It is unlikely that vitamin D supplements are beneficial in children and adolescents with normal vitamin D levels. The planned subgroup analyses by baseline serum vitamin D level suggest that vitamin D supplementation of deficient children and adolescents could result in clinically useful improvements, particularly in lumbar spine bone mineral density and total body bone mineral content, but this requires confirmation.

          Related collections

          Most cited references47

          • Record: found
          • Abstract: found
          • Article: not found

          Flexible regression models with cubic splines

          We describe the use of cubic splines in regression models to represent the relationship between the response variable and a vector of covariates. This simple method can help prevent the problems that result from inappropriate linearity assumptions. We compare restricted cubic spline regression to non-parametric procedures for characterizing the relationship between age and survival in the Stanford Heart Transplant data. We also provide an illustrative example in cancer therapeutics.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Meta-analysis of how well measures of bone mineral density predict occurrence of osteoporotic fractures.

            To determine the ability of measurements of bone density in women to predict later fractures. Meta-analysis of prospective cohort studies published between 1985 and end of 1994 with a baseline measurement of bone density in women and subsequent follow up for fractures. For comparative purposes, we also reviewed case control studies of hip fractures published between 1990 and 1994. Eleven separate study populations with about 90,000 person years of observation time and over 2000 fractures. Relative risk of fracture for a decrease in bone mineral density of one standard deviation below age adjusted mean. All measuring sites had similar predictive abilities (relative risk 1.5 (95% confidence interval 1.4 to 1.6)) for decrease in bone mineral density except for measurement at spine for predicting vertebral fractures (relative risk 2.3 (1.9 to 2.8)) and measurement at hip for hip fractures (2.6 (2.0 to 3.5)). These results are in accordance with results of case-control studies. Predictive ability of decrease in bone mass was roughly similar to (or, for hip or spine measurements, better than) that of a 1 SD increase in blood pressure for stroke and better than a 1 SD increase in serum cholesterol concentration for cardiovascular disease. Measurements of bone mineral density can predict fracture risk but cannot identify individuals who will have a fracture. We do not recommend a programme of screening menopausal women for osteoporosis by measuring bone density.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Prevalence of vitamin D deficiency among healthy adolescents.

              Although vitamin D deficiency has been documented as a frequent problem in studies of young adults, elderly persons, and children in other countries, there are limited data on the prevalence of this nutritional deficiency among healthy US teenagers. To determine the prevalence of vitamin D deficiency in healthy adolescents presenting for primary care. A cross-sectional clinic-based sample. An urban hospital in Boston. Three hundred seven adolescents recruited at an annual physical examination to undergo a blood test and nutritional and activity assessments. Serum levels of 25-hydroxyvitamin D (25OHD) and parathyroid hormone, anthropometric data, nutritional intake, and weekly physical activity and lifestyle variables that were potential risk factors for hypovitaminosis D. Seventy-four patients (24.1%) were vitamin D deficient (serum 25OHD level,
                Bookmark

                Author and article information

                Contributors
                Role: senior research fellow in general practice
                Role: endocrinologist
                Role: honorary associate and postdoctoral fellow
                Role: head of musculoskeletal unit
                Journal
                BMJ
                bmj
                BMJ : British Medical Journal
                BMJ Publishing Group Ltd.
                0959-8138
                1468-5833
                2011
                2011
                25 January 2011
                : 342
                : c7254
                Affiliations
                [1 ]Menzies Research Institute, University of Tasmania, Private Bag 23, Hobart, TAS 7000, Australia
                [2 ]Royal Hobart Hospital, Liverpool St Hobart, Tasmania
                [3 ]ASLaRC Aged Services Unit, Southern Cross University, Coffs Harbour, Queensland Australia
                Author notes
                Correspondence to: T Winzenberg tania.winzenberg@ 123456utas.edu.au
                Article
                wint804930
                10.1136/bmj.c7254
                3026600
                21266418
                5d3afec9-dc70-4493-bf35-469fe9b034eb
                © Winzenberg et al 2011

                This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.

                History
                : 22 November 2010
                Categories
                Research
                1600
                Clinical Trials (Epidemiology)
                Cleveland Clinic CME
                Internet

                Medicine
                Medicine

                Comments

                Comment on this article