Insufficiency and deficiency of vitamin D in elderly patients with fragility fractures of the hip in the Japanese population.

Background: Data of vitamin D sufficiency in Asian patients with osteoporotic fragility hip fractures are limited. This study aimed to obtain data from the Japanese population. Methods: Patients aged 60 years or older with hip fractures were prospectively enrolled. Serum 25-hydroxyvitamin D (25(OH)D) levels were measured. Levels were compared between patients receiving and not receiving treatment for osteoporosis, those with and without previous contralateral hip fractures, and those with femoral neck versus trochanteric fractures. Sex-based differences were also assessed. The serum levels in patients younger than 60 years with extremity fractures were assessed, and differences between elderly and younger patients were evaluated. The individual correlation between 25(OH)D levels and the ultraviolet (UV) index and age was analyzed in elderly patients with hip fractures. Results: The data of 360 patients (aged 84.7 +/- 8.2 years), comprising 80 men and 280 women, were analyzed. The mean 25(OH)D level was 16.5 +/- 7.2 ng/mL. The prevalence of vitamin D insufficiency (25(OH)D <30 ng/mL) and deficiency (25(OH)D <20 ng/mL) was 93.9% and 71.7%, respectively. A significant difference was noted in the prevalence of vitamin D deficiency between patients with and without previous contralateral hip fractures. Age and 25(OH)D levels were found to be correlated, with no correlation between the UV index and the 25(OH)D levels. The 25(OH)D level in the younger population (n = 123) was 20.7 +/- 8.6 ng/mL, which was significantly higher than that of the elderly. Conclusion: Perennial vitamin D insufficiency is prevalent in elderly Japanese patients with hip fractures.