Radiographic osteoarthritis and obesity

To determine the association between obesity and radiographic osteoarthritis (OA) of the knee and generalized OA.

A cross-sectional survey of patients attending 14 primary clinics for a variety of medical complaints was conducted. They were consented, interviewed, examined and radiographed for the presence of knee and generalized OA. The association between OA and weight was then assessed. This study was carried out in 14 primary care clinics in North Riyadh, Kingdom of Saudi Arabia, between September 1998 through to March 1999.

Two hundred and nineteen patients (118 males, 101 females) completed the study and their results were analyzed. We found a strong association between excess weight and knee OA in females [overall ratio (OR) 3.28 (95% confidence intervals (CI), 2.07-5.36)] and a weaker link with knee OA in males [OR 1.88 (95% CI, 1.24-2.92)]. Generalized OA was found to be associated with obesity in females only [OR 1.93 (95% CI, 1.09-3.43)]. Reporting of joint symptoms in patients with radiographic knee OA was also associated with obesity (P=0.0001).

Excess weight is strongly associated with knee OA in females and symptoms of joint pain in all OA patients, with a weaker but still significant link with male knee OA and generalized OA in females.