Gladman DD, Ye JY, Chandran V, et al. - In this study population of psoriatic arthritis (PsA) patients, oligoarticular disease was evident in 47% of cases and was similar to polyarticular disease. SF-36 MCS (36-item Short Form Health Survey mental component summary) was the sole predictor for progression to polyarthritis.

• PsA patients with oligoarticular presentation were compared with those with polyarticular disease in this study.

• A total of 407 PsA patients with ≥ 2 clinic visits were included, 192 (47%) had oligoarthritis.

• Despite similar demographic features, dactylitis and enthesitis was present in more patients with polyarthritis.

• Similar joint distribution, most often involving small joints of the hands and feet, was evident.

• Higher Health Assessment Questionnaire and lower SF-36 scores were detected in polyarthritis cases.

• 61% of patients with oligoarticular disease remained oligoarticular and 39% progressed to polyarthritis.