Clinical and Patient-reported Outcomes in Patients with Psoriatic Arthritis (PsA) by Body Surface Area Affected by Psoriasis: Results from the Corrona PsA/Spondyloarthritis Registry

Objective. Psoriatic arthritis (PsA) is commonly comorbid with psoriasis; the extent of skin lesions is a major contributor to psoriatic disease severity/burden. We evaluated whether extent of skin involvement with psoriasis [body surface area (BSA) > 3% vs <= 3%] affects overall clinical and patient-reported outcomes (PRO) in patients with PsA. Methods. Using the Corrona PsA/Spondyloarthritis Registry, patient characteristics, disease activity, and PRO at registry enrollment were assessed for patients with PsA aged >= 18 years with BSA > 3% versus <= 3%. Regression models were used to evaluate associations of BSA level with outcome [modified minimal disease activity (MDA), Health Assessment Questionnaire (HAQ) score, patient-reported pain and fatigue, and the Work Productivity and Activity Impairment questionnaire score]. Adjustments were made for age, sex, race, body mass index, disease duration, and history of biologics, disease-modifying antirheumatic drug, and prednisone use. Results. This analysis included 1240 patients with PsA with known BSA level (n = 451, BSA > 3%; n = 789, BSA = 3%). After adjusting for potential confounding variables, patients with BSA > 3% versus = 3% had greater patient-reported pain and fatigue and higher HAQ scores (p = 2.33 x 10(-8), p = 0.002, and p = 1.21 x 10(-7), respectively), were 1.7x more likely not to be in modified MDA (95% CI 1.21-2.41, p = 0.002), and were 2.1x more likely to have overall work impairment (1.37-3.21, p = 0.0001). Conclusion. These Corrona Registry data show that substantial skin involvement (BSA > 3%) is associated with greater PsA disease burden, underscoring the importance of assessing and effectively managing psoriasis in patients with PsA because this may be a contributing factor in PsA severity.