Background/Purpose: This study aimed to quantify the direct and indirect costs of psoriatic arthritis (PsA) at a single center in Toronto, Ontario and to assess whether these costs varied with respect to socioeconomic status.

Methods: Participants were identified from the Psoriatic Arthritis Clinic at Toronto Western Hospital in Toronto, Ontario. To be included in the study, patients fulfilled the Classification criteria for Psoriatic Arthritis (CASPAR) and attended the clinic for ≥ 1 year. Participants were excluded if they were <18 years old or if they were non-English speakers.

Consented participants completed a questionnaire that included healthcare utilization, out-of-pocket expenses, and productivity losses in the preceding 12 months. Results from this survey were supplemented with a chart review of participant’s prescription medication in the past year, demographic information, socioeconomic characteristics, and disease severity measures.

Direct costs were estimated according to the Ontario Drug Benefit Formulary, Ontario Health Insurance Plan, or industry averages. Indirect costs were estimated from productivity losses due to sick days or early retirement. Age, sex, education, marital status, employment status and household income were used as indicators of socioeconomic status. The relationship between cost of PsA and socioeconomic status was assessed using the Kruskal-Wallis test, with significance of p <0.05.

Results: Of the 188 patients included in the study, the mean annual direct cost of PsA was $15,802 per patient, of which $5,499 and $10,219 accounted for non-pharmacologic and pharmacologic costs, respectively. Women, unemployed, and lower income patients had significantly higher non-pharmacologic costs, whereas patients under the age of 65 had significantly higher pharmacologic costs compared to their counterparts. Thirteen % of patients were unemployed due to psoriatic arthritis, with an average 3.3 years of lost employment.

Conclusion: This study showed that PsA generates a substantial economic burden for patients in Toronto, Ontario. This burden is composed of healthcare resource consumption as well as productivity loss due to early retirement. Furthermore, age, sex, employment status, and income are all significantly associated with the direct cost of PsA. Information from this study will help to estimate the cost-effectiveness of new PsA medications and to allocate healthcare resources more effectively to certain socioeconomic groups in need.