Prevalence of osteoarthritis in rural areas of Iran: a WHO-ILAR COPCORD study

Aim To estimate the prevalence of osteoarthritis (OA) of different joints in rural areas of Iran. Methods From five villages of Tuyserkan County, 1565 individuals were randomly selected and were interviewed to complete the Community Oriented Programme for Control of the Rheumatic Diseases (COPCORD) Core Questionnaire. Among these cases 1192 cases with rheumatic complaints were examined by a rheumatologist and laboratory and radiology tests were performed if necessary for the diagnosis. Definition of OA in various joints, were based on American College of Rheumatology (ACR) criteria. Results About 20% of the study population had OA in at least one of their joints. Prevalence of OA in the knee joint was 19.34%, in hand joins was 2.66% and in the neck was 2.21%. The most common findings on physical examination of patients with knee OA, hand OA and neck OA were bony crepitus (88.9%), Heberden's nodes (73.2%) and pain on movement (59.9%), respectively. Conclusions This study revealed that OA in rural areas of Iran was more frequent in comparison with urban areas of Iran. Moreover, the prevalence of OA in rural areas of Iran was higher in comparison with prevalence of OA in rural areas of other Asian countries. Similar to previous studies OA was more frequently detected in the knee joint.