Falls among elderly individuals occur frequently, increase with age,
and lead to substantial morbidity and mortality. The role of vitamin D in
preventing falls among elderly people has not been well established.
To assess the effectiveness of vitamin D in preventing an older person
MEDLINE and the Cochrane Controlled Trials Register from January 1960
to February 2004, EMBASE from January 1991 to February 2004, clinical experts,
bibliographies, and abstracts. Search terms included trial terms: randomized-controlled trial or controlled-clinical
trial or random-allocation or double-blind method, or single-blind method or uncontrolled-trials with vitamin D terms: cholecalciferol or hydroxycholecalciferols or calcifediol or dihydroxycholecalciferols or calcitriol or vitamin
D/aa[analogs & derivates] or ergocalciferol or vitamin D/bl[blood]; and with accidental
falls or falls, and humans.
We included only double-blind randomized, controlled trials (RCTs) of
vitamin D in elderly populations (mean age, 60 years) that examined falls
resulting from low trauma for which the method of fall ascertainment and definition
of falls were defined explicitly. Studies including patients in unstable health
states were excluded. Five of 38 identified studies were included in the primary
analysis and 5 other studies were included in a sensitivity analysis.
Independent extraction by 3 authors using predefined data fields including
study quality indicators.
Based on 5 RCTs involving 1237 participants, vitamin D reduced the corrected
odds ratio (OR) of falling by 22% (corrected OR, 0.78; 95% confidence interval
[CI], 0.64-0.92) compared with patients receiving calcium or placebo. From
the pooled risk difference, the number needed to treat (NNT) was 15 (95% CI,
8-53), or equivalently 15 patients would need to be treated with vitamin D
to prevent 1 person from falling. The inclusion of 5 additional studies, involving
10 001 participants, in a sensitivity analysis resulted in a smaller
but still significant effect size (corrected RR, 0.87; 95% CI, 0.80-0.96).
Subgroup analyses suggested that the effect size was independent of calcium
supplementation, type of vitamin D, duration of therapy, and sex, but reduced
sample sizes made the results statistically nonsignificant for calcium supplementation,
cholecalciferol, and among men.
Vitamin D supplementation appears to reduce the risk of falls among
ambulatory or institutionalized older individuals with stable health by more
than 20%. Further studies examining the effect of alternative types of vitamin
D and their doses, the role of calcium supplementation, and effects in men
should be considered.