Rheumatoid arthritis, corticosteroid therapy and hip fracture.
OBJECTIVE--To identify the risk of hip fracture in patients with rheumatoid arthritis and those taking corticosteroids. METHODS--In a population based case-control study, we compared 300 consecutive patients with hip fracture aged 50 years and over from a defined district and 600 age and sex matched community controls. RESULTS--The risk of hip fracture was increased in patients with rheumatoid arthritis (odds ratio (OR) 2.1; 95% confidence interval (CI) 1.0 to 4.7) and those receiving corticosteroids (OR 2.7; 95% CI 1.2 to 5.8). The risk attributable to rheumatoid arthritis was markedly reduced by adjusting for functional impairment, while that for steroid use remained after adjusting for body mass index, smoking, alcohol, and functional status. CONCLUSIONS--Hip fracture risk is approximately doubled amongst patients with rheumatoid arthritis and among those taking steroids. These risk increases are, to some extent, independent of each other. In rheumatoid arthritis, the risk was most closely associated with functional impairment, whereas steroid use did not appear to be confounded by this variable.