Aims: To perform a meta-analysis on the published studies of serum levels of 25 hydroxyvitamin D in older people with fractures of the proximal femur compared to control groups.
Methods: A 'Medline' literature search using key words vitamin D' and 'hip fractures' for the years January 1966 to June 1999, seeking only papers published in English and available from New Zealand medical libraries, was performed. Bibliographies of identified papers were also searched. Studies which compared 25 hydroxyvitamin D levels in people with a fracture of the proximal femur to an older control group were eligible for inclusion. 30 studies were identified and 28 papers could be found in New Zealand. The method of weighted Z statistics was used in the meta-analysis.
Results: The pooled reduction in serum 25 hydroxyvitamin D for the fracture group compared to the controls was 0.66 of a standard deviation with a 95% confidence interval of 0.74 to 0.59.
Conclusions: Although there may be publication bias in this meta-analysis and there was some evidence of heterogeneity in the studies, there is very good evidence that older people with fracture of the proximal femur have reduced levels of vitamin D compared to controls. Older people with fracture of the proximal femur should be treated with vitamin D.