Prevalence of psoriatic arthritis in patients with psoriasis: A systematic review and meta-analysis of observational and clinical studies.
Background: Wide-ranging prevalence estimates of psoriatic arthritis (PsA) in patients with psoriasis have been reported.
Objectives: To assess the prevalence and incidence of PsA in patients with psoriasis.
Methods: Two authors independently searched three databases for studies reporting on the prevalence or incidence of PsA in patients with psoriasis. A proportion meta-analysis was performed to calculate the pooled proportion estimates of PsA in patients with psoriasis.
Results: A total of 266 studies were included, examining 976,408 patients with psoriasis. Overall, the pooled proportion (95% confidence interval) of PsA among patients with psoriasis was 19.7% (18.5%-20.9%). In children and adolescents (<18 years), the pooled prevalence was 3.3% (2.1%-4.9%). The PsA prevalence was 22.7% (20.6%-25.0%) in European, 21.5% (15.4%-28.2%) South American, 19.5% (17.1%-22.1%) North American, 15.5% (0.009%-51.5%) African, and 14.0% (11.7%-16.3%) in Asian psoriasis patients. The prevalence of PsA was 23.8% (20.1%-27.6%) in studies where the ClASsification criteria for Psoriatic ARthritis (CASPAR) was applied. The incidence of PsA among psoriasis patients ranged from 0.27 to 2.7 per 100 person-years.
Limitations: Between-study heterogeneity may have affected the estimates.
Conclusions: We found that one in five patients with psoriasis have PsA. With the growing recognition of CASPAR, more homogenous and comparable prevalence estimates are expected to be reported.