Vitamin D deficiency is associated with an increased risk of falls and fractures. Assuming this association is causal, we aimed to identify the number and proportion of hospitalisations for falls and hip fractures attributable to vitamin D deficiency (25 hydroxy D (25(OH)D) <50 nmol/l) in Australians aged ≥65 years. We used 25(OH)D data from the 2011/12 Australian Health Survey and relative risks from published meta-analyses to calculate population-attributable fractions for falls and hip fracture. We applied these to data published by the Australian Institute of Health and Welfare to calculate the number of events each year attributable to vitamin D deficiency. In men and women combined, 8·3 % of hospitalisations for falls (7991 events) and almost 8 % of hospitalisations for hip fractures (1315 events) were attributable to vitamin D deficiency. These findings suggest that, even in a sunny country such as Australia, vitamin D deficiency contributes to a considerable number of hospitalisations as a consequence of falls and for treatment of hip fracture in older Australians; in countries where the prevalence of vitamin D deficiency is higher, the impact will be even greater. It is important to mitigate vitamin D deficiency, but whether this should occur through supplementation or increased sun exposure needs consideration of the benefits, harms, practicalities and costs of both approaches.
