EFFECT OF VITAMIN D SUPPLEMENTATION ON MUSCLE FUNCTION IN ELDERLY INDIVIDUALS: A META-ANALYSIS

Abstract

AbstractBackground: Sarcopenia (the loss of muscle mass and strength) has estimated prevalence rates of 5-13% and 11-50% in the young-old and old-old, respectively. Recent studies have shown that vitamin D plays important roles in various systems, including the musculoskeletal system. Objective:The aim of this meta-analysis was to determine the effects of vitamin D supplementation on muscle function in community‐dwelling elderly individuals.Methods: We conducted systematic searches of PubMed, Medline, Egyptian Knowledge Bank, and the reference sections of previous reviews, and we discussed the topic with several experts in the field. Only randomized controlled trials that evaluated the effect of vitamin D supplementation on muscle function [muscle strength was evaluated by the hand grip strength (HGS) test, and physical performance was evaluated by the timed up-and-go (TUG) test] were included. Only studies published in English between January 2000 and June 2018 were considered.Results: In total, 14 randomized controlled clinical trials (RCTs) met our inclusion criteria. The participants in these studies were all community-dwelling elderly individuals, who were generally in good health for their age. The pooled mean difference in HGS was higher in the vitamin D supplementation group than in the control group. The pooled mean difference in the TUG test was slightly lower in the vitamin D supplementation group than in the control group.Conclusions: Our meta-analysis shows that vitamin D supplementation could improve muscle function in elderly individuals. Future studies should use standardized durations and doses of vitamin D supplementation.