Medium doses of daily vitamin D decrease falls and higher doses of daily vitamin D3 increase falls: A randomized clinical trial

• Published in: The Journal of steroid biochemistry and molecular biology Vol. 173; pp. 317 - 322
• Main Authors: Smith, Lynette M., Gallagher, J. Christopher, Suiter, Corinna
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2017
• Subjects: Accidental Falls - prevention & control; Aged; Cholecalciferol - administration & dosage; Cholecalciferol - blood; Cholecalciferol - therapeutic use; Clinical trial; Dietary Supplements - analysis; Double-Blind Method; Falls; Female; Humans; Middle Aged; Vitamin D - administration & dosage; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D - therapeutic use; Vitamin D Deficiency - blood; Vitamin D Deficiency - drug therapy; Vitamin D supplementation; Vitamins - administration & dosage; Vitamins - blood; Vitamins - therapeutic use; Falls; Clinical trial; Vitamin D supplementation
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/j.jsbmb.2017.03.015

•One year double blind trial, 7 daily oral doses of vitamin D or placebo, on incidence Fallers.•Faller rate was a U shaped curve, maximum decrease on doses 1600–3200 IU or serum 25OHD of 32–38ng/ml.•High vitamin D dose 4000–4800 IU increases Faller incidence in those with previous Fall history. Falls are a serious health problem in the aging population. Because low levels of vitamin D have been associated with increased fall rates, many trials have been performed with vitamin D; two meta-analyses showed either a small effect or no effect of vitamin D on falls. We conducted a study of the effect of vitamin D on serum 25 hydroxyvitamin D (25OHD) and data on falls was collected as a secondary outcome. In a 12-month double blind randomized placebo trial, elderly women, mean age 66 years, were randomized to one of seven daily oral doses of vitamin D or placebo. The main inclusion criterion for study was a baseline serum 25OHD<20ng/ml (50nmol/L). A history of falls was collected at baseline and fall events were collected every 3 months. Results showed that the effect of vitamin D on falls followed a U-shaped curve whether analyzed by dose or serum 25OHD levels. There was no decrease in falls on low vitamin D doses 400, 800 IU, a significant decrease on medium doses 1600, 2400,3200 IU (p=0.020) and no decrease on high doses 4000, 4800 IU compared to placebo (p=0.55). When compared to 12-month serum 25OHD quintiles, the faller rate was 60% in the lowest quintile <25ng/ml (<50nmol/L), 21% in the low middle quintile 32–38ng/ml (80–95nmo/L), 72% in the high middle quintile 38–46ng/ml (95–115nmo/L) and 45% in the highest quintile 46–66ng/ml (115–165nmol/L). In the subgroup with a fall history, fall rates were 68% on low dose, 27% on medium doses and 100% on higher doses. Fall rates on high doses were increased compared to medium doses (Odds Ratio 5.6.95% CI: 2.1–14.8). In summary, the maximum decrease in falls corresponds to a 12- month serum 25OHD of 32–38ng/ml (80–95nmol/L) and faller rates increase as serum 25OHD exceed 40–45ng/ml (100–112.5nmol/L). The Tolerable upper limit (TUL) recently increased in 2010 from 2000 to 4000 IU/day may need to be reduced in elderly women especially in those with a fall history.