[Vitamin D deficiency and related factors in patients with osteoporotic hip fracture]

Hypovitaminosis D is frequent in the elderly, and it is especially prevalent among patients with hip fracture. The prevalence of vitamin D deficiency and its related factors are not well known in our population. The objective of this study was to determine the prevalence of hypovitaminosis D in patients with osteoporotic hip fracture and to analyze which factors are associated with this deficit.

Transversal study. Inclusion of all consecutive patients older than 65 years, admitted in our hospital with osteoporotic hip fracture during the period of March 2002-February 2003. The prevalence of hypovitaminosis D and secondary hyperparathyroidism were analysed. Sunlight exposure, functional and nutritional status, and presence of comorbidity were investigated.

324 patients were included. Mean (standard deviation) age was 83 (7) years, and 80% were female. Vitamin D deficiency was observed in 217 cases (67%; 95% confidence interval [CI], 62-72%); and 57% of these patients had secondary hyperparathyroidism. A low nutritional status -albumin < 4 g/l (odds ratio [OR] = 4.5; 95% CI, 1.3-16; p = 0.019)- and a low functional status (Barthel index < 60; OR = 3; 95% CI, 1.3-6.7; p = 0.008) - were factors independently associated with hypovitaminosis D. However, an active sunlight exposure was a protective factor (OR = 0.09; 95% CI, 0.02-0.5; p = 0.004).

The prevalence of hypovitaminosis D is high in patients with osteoporotic hip fracture, and in more than a half of the cases a secondary hyperparathyroidism is observed. The vitamin D deficiency is especially prevalent among patients with low sunlight exposure and low nutritional and functional status.