Background/Purpose: PsA is associated with higher rates of developing certain comorbidities, but little has been done to understand the incidence rates of comorbidities in American populations. This study compared incidence rates of comorbidities between patients with newly diagnosed PsA and a matched control cohort without PsA, using a large national US claims database.

Methods: Adults with ≥1 inpatient or 2 outpatient diagnoses of PsA (ICD-9-CM 696.0) in 1/1/2008 – 9/30/2015 were extracted from MarketScan Commercial and Medicare Databases, with the first PsA diagnosis as the index date. Patients had ≥24 months continuous enrollment prior to the index date (pre-period) and were followed for ≥12 months until the earliest of inpatient death, end of continuous enrollment, or end of the data. These PsA patients were matched on calendar year, age, gender, and geographic region to those with no PsA diagnosis anytime in 2007-2015 (controls). The incidence of new comorbidities (not present in the 24-month pre-period) per 100 person-years was estimated and compared between PsA patients and their controls.

Results: A total of 14,898 PsA patients were matched to 35,037 controls (mean age:  53.4 years for PsA vs. 54.8 for controls; male: 44.6% vs. 44.4%; mean length of follow up: 3.0 vs. 3.0 years). Compared with controls, PsA patients had higher incidence rate of autoimmune disease, cardiovascular disease, fatigue, eczema, obesity/overweight, depression, anxiety, smoking, cancer, diabetes, alcohol use, osteoporosis, uveitis, and liver disease (Figure 1). Figure 1. Incidence Rates per 100 Person-Years of New Comorbidities for PsA vs. Controls    

Conclusion:   PsA patients had high incidence rates of cardiovascular comorbidities, autoimmune conditions, fatigue, eczema, depression, and anxiety than controls.  Understanding these comorbidity profiles will help evaluate the impact of comorbid conditions on disease management and costs associated with PsA.