Patient characteristics, treatment patterns and disease outcomes in patients with psoriatic arthritis followed in a combined Dermatology–Rheumatology clinic: a retrospective real-world study

The aim of this study was to assess the patient characteristics, treatment patterns and disease outcomes in patients with psoriatic arthritis (PsA) referred to a combined Dermatology–Rheumatology (Derm–Rheum) Clinic. This was a retrospective study of patients seen in a combined Derm–Rheum Clinic (February 2018 to June 2020) in a Tertiary University Hospital. Consecutive patients with suspicious musculoskeletal symptoms or a known diagnosis of PsA referred to the Derm–Rheum Clinic were examined and followed simultaneously by experienced dermatologists and rheumatologists. Among 151 patients with psoriasis (PSO) with suspicious musculoskeletal complaints, 129 (85%) with a final diagnosis of PsA were included (56% females, mean age: 55 years, median disease duration: 14.2 years). In 62% of these patients (n = 94), PsA was diagnosed for the 1st time. At initial evaluation, 95% had peripheral arthritis, 45% nail involvement, 23% axial involvement, 12% enthesitis and 6% dactylitis with a median DAPSA and PASI scores of 20.5 and 1.6, respectively. 31% of the patients were not receiving any systemic treatment, 45% were on biologics, 29% on non-biologics and 10% on targeted synthetic agents (apremilast). At last visit (median interval time: 15 months), only 8% did not receive any systemic therapy (p < 0.001 compared to 1st visit), 62% were on biologics (p = 0.009 compared to 1st visit), 46% on non-biologics (p = 0.01 compared to 1st visit) and 10% remained on apremilast. The median DAPSA and PASI scores decreased significantly to 5.3 and 0, respectively. In conclusion, about 2/3 of patients with PSO and musculoskeletal complaints referred to a combined Derm–Rheum Clinic were diagnosed for the 1st time with PsA. During follow-up, the percentage of PsA patients on systemic therapies significantly increased with major improvement of disease activity indices. These data emphasize the value of combined Derm–Rheum Clinics for earlier referral, diagnosis, and more effective treatment of PsA patients.