Association of 25-Hydroxyvitamin D With Prevalent Osteoarthritis of the Hip in Elderly Men The Osteoporotic Fractures in Men Study

Objective. To examine the cross-sectional association of serum levels of 25-hydroxyvitamin D, or 25(OH) D, with prevalent radiographic hip osteoarthritis (OA) in elderly men. Methods. In a cohort of 1,104 elderly men from the Osteoporotic Fractures in Men Study, 25(OH) D serum levels were determined by mass spectrometry, followed by pelvic radiographs similar to 4.6 years later. Categories of vitamin D levels were defined as follows: deficiency as <= 15 ng/ml, insufficiency as 15.1-30 ng/ml, and sufficiency as >30 ng/ml. Radiographs were assessed for severity of hip OA using a summary grade of 0-4 for individual features of hip OA. Logistic regression was used to assess associations of serum 25(OH) D levels with prevalent radiographic hip OA; covariates included age, clinic site, season at the time of blood withdrawal, self-reported hip pain for >30 days, timed 6-meter walk, presence of at least 1 coexisting condition, and self-rated health status. Results. Men with radiographic hip OA had a slower 6-meter walking time (P < 0.0001), reported more hip pain (P = 0.0001), had a lower vitamin D level (P = 0.0002), and had a higher prevalence of vitamin D insufficiency (P = 0.002) and vitamin D deficiency (P = 0.012) compared with controls. Higher 25(OH) D levels were associated with a lower prevalence of radiographic hip OA (odds ratio [OR] 1.39 per 1 SD decrease in 25[OH] D, 95% confidence interval [95% CI] 1.11-1.74) after adjusting for age, season, and clinic site. Men with vitamin D insufficiency had an increased likelihood of prevalent radiographic hip OA (OR 2.19, 95% CI 1.21-3.97) compared with men with sufficient levels of 25(OH) D, and in men with vitamin D deficiency, there was a tendency toward an increased likelihood of radiographic hip OA (OR 1.99, 95% CI 0.83-4.74). Conclusion. Men with vitamin D deficiencies are twice as likely to have prevalent radiographic hip OA, and therefore vitamin D therapy to augment skeletal health in the elderly is warranted.