This study assessed the comorbidity burden and direct healthcare costs associated with psoriatic arthritis (PsA). Adults (18-64 years) with ≥ 2 claims for a PsA diagnosis ≥ 30 days apart in the Truven Health MarketScan database (July 2009-June 2014) were selected as the case group. The index date was randomly selected after the first claim for PsA. Controls free of PsA and psoriasis (PsO) in their entire claims history were assigned the same index date and were matched with the cases on age, gender, and geographic region. All patients had ≥ 12 months of continuous eligibility before and after (study period) the index date. PsA-associated comorbidities, medication use, and medical service utilization were compared between matched groups using Wilcoxon signed rank and McNemar's tests. Costs were compared using multivariable generalized linear models. The 35,061 matched pairs had a mean age of 49.11 ± 10.20 years and 52.73% were female. During the study period, PsA patients had more PsA-associated comorbidities and significantly higher medication use than controls (all-cause medications 96.64 vs. 78.95%, p < 0.0001). PsA patients had significantly greater medical service use (inpatient admissions, hospitalization days, emergency room visits, outpatient services; all p < 0.0001) and higher annual direct healthcare costs per patient than controls (adjusted cost difference [ACD] = $18,482, including higher medical costs [ACD = $6440] and all-cause pharmacy costs [ACD = $11,737]; all p < 0.0001). Overall, PsA patients had a significantly higher PsA-related comorbidity burden, healthcare utilization, and direct healthcare costs than people free of PsA and PsO, underscoring the need for more effective treatments and improved care delivery systems.
Keywords: Comorbidity; Direct healthcare costs; Healthcare resource utilization; Psoriatic arthritis.