Association of physician specialty with psoriatic arthritis treatment and costs

To describe current psoriatic arthritis treatment and costs by provider specialty using real-world claims data.

Observational, retrospective cohort study of patients in the IBM MarketScan Commercial and supplemental Medicare databases.

Eligible patients had newly diagnosed psoriatic arthritis with 12 months of continuous enrollment pre- and post index date for their initial claim. Patients were assigned to 1 of 5 provider specialty cohorts. During the 1-year follow-up period, we collected psoriatic arthritis treatment agent and regimen type and total annual medical and health care costs. We used multivariate regression models to determine the conditional associations of provider specialty with costs.

A total of 2132 patients with incident psoriatic arthritis qualified. Most providers were rheumatologists (n = 1365; 64%). Rheumatologists commonly prescribed oral small molecules (methotrexate, 56.3% of prescriptions; sulfasalazine, 8.6%; apremilast, 7.0%) as the index therapy, whereas 23.8% of prescriptions were for tumor necrosis factor inhibitors (adalimumab, 14.2%; etanercept, 7.9%; and infliximab, 1.7%). Compared with other specialists, dermatologists prescribed biologics and other specialty drugs more frequently-adalimumab (32.7%), apremilast (14.3%), etanercept (11.6%), and ustekinumab (8.8%)-and methotrexate less frequently (30.6%). The greatest unadjusted median health care costs were observed among dermatologists ($45,548) compared with rheumatologists ($30,411), primary care physicians ($29,927), rheumatologists/dermatologists ($27,393), and other specialists ($27,774). However, after adjusting for patient-level factors, multivariate regression analyses found that provider specialty was not associated with higher health care costs.

In patients with newly diagnosed psoriatic arthritis, physician specialty was associated with different medication choices but not costs.