[Prognostic factors in the evolution of psoriatic arthritis].
BACKGROUND: The aim of this study is to determine the evolution and prognostic factors in the patients with psoriatic arthritis. PATIENTS AND METHODS: We have reviewed retrospectively the follow-up of 96 patients with psoriatic arthritis seen in our service. We have collected the following data at onset of the disease: age and sex, age at onset of cutaneous and articular manifestations, clinical form, distal interphalangeal affection, axial involvement, erythrocyte sedimentation rate, rheumatoid factor, antinuclear antibody and HLA antigen. Likewise, we have collected the present functional class. We have correlated the data at onset of the disease with the present functional class. RESULTS: Mean +/- SD age of 96 patients (48 male, 48 female) was 51 +/- 14 years. The majority of patients (78%) were in ACR functional class I or II. The most frequent clinical form was the oligoarticular (46%), except in the female group, in which the most frequent was the symmetric polyarticular one (46%). We found statistically significant correlation between the present functional class and the clinical form at onset and the disease duration. We didn't found a statistically correlation between the present functional class and the axial involvement. CONCLUSIONS: Patients with psoriatic arthritis and symmetric polyarthritis are more frequently female, and have a worse prognosis. The axial involvement does not imply a worse prognosis.