Where we Live matters: Varied Disease Burden and Treatment Patterns in Psoriatic Arthritis in the United States.

OBJECTIVE To evaluate the clinical characteristics, social deprivation, insurance coverage, and medication use across regional subsets of patients with psoriatic arthritis (PsA) in the US. METHODS A cross-sectional study of PsA patients in the Rheumatology Informatics System for Effectiveness (RISE) registry between January 2020 and March2023 was conducted. Distribution of high disease activity (HDA - RAPID3>12), high comorbidity (RxRisk ≥90th percentile), high Area Deprivation Index (ADI ≥80), insurance coverage, prednisone ≥10mg daily, and all DMARD therapies across geographic regions were evaluated. Logistic regression models were used to identify regional correlates of HDA and comorbidity. RESULTS Of 32,732 PsA RISE patients, 58.8% were White females [mean (SD) age 57.7(13.5) years] with private insurance (60%); 55.8% resided in the South. A majority (81.8%) had a BMI of ≥25, highest in the Midwest (32.4 ±7.8). Women, despite prevalent HDA, received less bDMARD therapy. Both HDA and ADI ≥80 were more prevalent in the South and Midwest. Compared to the Northeast, Midwest patients had a higher burden of comorbidity [aOR:1.59, 95% CI 0.98 - 2.59] with frequent use of prednisone in conjunction with conventional DMARDs (31.3% vs. Northeast 20.5%, South 13.6%, West 17.6%). Uveitis affected 1.2% of the cohort. Only 14 (7.1%) and 20 (10.1%) RISE practices provided care for half of all Medicaid and high deprivation patients, respectively. CONCLUSIONS PsA disease characteristics and care vary across the US, with higher-than-expected prednisone use, and unequal provider care burden in some regions. Further work is needed to assess the impact of varied regional care on disease outcomes.