Inclusion of 95 % range in the model to account for inter-individual variability increased the predicted intake of vitamin D needed to maintain serum 25(OH)D ≥ 50 nmol/l to 930 IU/d .
Does daily vitamin D 800 IU and calcium 1000 mg supplementation decrease the risk of falling in ambulatory women aged 65-71 years? A 3-year randomized population-based trial (OSTPRE-FPS).
OBJECTIVE The hypothesis was that the calcium and vitamin D supplementation prevents falls at the population level . STUDY DESIGN The OSTPRE-FPS was a r and omized population -based open-trial with 3-year follow-up . The supplementation group ( n=1566 ) received daily cholecalciferol 800IU+calcium carbonate 1000 mg , while the  control group ( n=1573 ) received no supplementation or placebo .  A r and omly selected sub sample of 593 subjects underwent a detailed measurement program including serum 25(OH)D measurements . MAIN OUTCOME MEASURE The occurrence of falls was the primary outcome of the study . The participants in the sub sample were telephoned at 4 months intervals and the rest of the trial population was interviewed by phone once a year . RESULTS In the entire trial population ( ETP ) , there were 812 women with 1832 falls in the intervention group and 833 women with 1944 falls in the control group ( risk ratio was 0.98 , 95 % CI 0.92 - 1.05 , P=0.160 ) . The supplementation was not associated with single or multiple falls in the ETP . However , in the sub sample , multiple fall incidence decreased by 30 % ( odds ratio ( OR ) 0.70 , 95 % CI 0.50 - 0.97 , P=0.034 ) in the supplementation group . Further , the supplementation decreased the incidence of multiple falls requiring medical attention ( OR 0.72 , 95 % CI 0.53 - 0.97 , P=0.031 ) in the ETP . The mean compliance in the entire trial population was 78 % and in the sub sample 79 % . DISCUSSION Overall , the primary analysis showed no association between calcium and vitamin D supplementation and risk of falls . However , the results of a post hoc analysis suggested that there was a decreased risk of multiple falls requiring medical attention : this finding requires confirmation
Inclusion of 95 % range in the model to account for inter-individual variability increased the predicted intake of vitamin D needed to maintain serum 25(OH)D ≥ 50 nmol/l to 930 IU/d .