Predictive factors of psoriatic arthritis in a diverse population with psoriasis

Objective We aimed to analyze the clinical characteristics of patients with psoriasis and determine the predictive factors of psoriatic arthritis (PsA). Methods This retrospective cohort study was performed among patients with psoriasis. Demographic and clinical data were collected. Psoriasis treatment was categorized as topical agents, phototherapy, oral therapy, and biologics. Predictive factors of PsA development were determined using logistic regression analyses. Results We included 330 patients with psoriasis, and 83 (25%) patients developed PsA. Thirty-eight (45.8%) patients who developed PsA were Malay, 24 (28.9%) were Chinese, and 21 (25.3%) were Indian. The mean age of patients with PsA was 54.2 (±15.8) years, and the duration from diagnosis of psoriasis to diagnosis of PsA was 36 (3.5–114) months. Predictive factors for developing PsA were female sex (odds ratio [OR] = 3.33, 95% confidence interval [CI] 1.78–6.22), presence of nail involvement (OR = 5.36, 95% CI 2.50–11.51), severe psoriasis (OR = 27.41, 95% CI 7.58–99.11), and oral systemic therapy prior to PsA diagnosis (OR = 4.09, 95% CI 2.04–8.22). Conclusion Patients with psoriasis who are female, have nail involvement, severe skin psoriasis, and require oral systemic therapy for psoriasis may have an increased risk of developing PsA.