Healthcare costs in psoriasis and psoriasis sub-groups over time following psoriasis diagnosis

Aims: To quantify healthcare costs in patients with psoriasis overall and in psoriasis patient sub-groups, by level of disease severity, presence or absence of psoriatic arthritis, or use of biologics. Methods: Administrative data from Truven Health Analytics MarketScan Research Database were used to select adult patients with psoriasis from January 2009 to January 2014. The first psoriasis diagnosis was set as the index date. Patients were required to have >= 6 months of continuous enrollment with medical and pharmacy benefits pre-index and >= 12 months post-index. Patients were followed from index until the earliest of loss to follow-up or study end. All-cause healthcare costs and outpatient pharmacy costs were calculated for the overall psoriasis cohort and for the six different psoriasis patient sub-groups: (a) patients with moderate-to-severe disease and mild disease, (b) patients with psoriatic arthritis and those without, and (c) patients on biologics and those who are not. Costs are presented per-patient-per-year (PPPY) and by years 1, 2, 3, 4, and 5 of follow-up, expressed in 2014 US dollars. Results: A total of 108,790 psoriasis patients were selected, with a mean age of 46.0 years (52.7% females). Average follow-up was 962 days. All-cause healthcare costs were $ 12,523 PPPY. Outpatient pharmacy costs accounted for 38.6% of total costs. All-cause healthcare costs were highest for patients on biologics ($ 29,832), then for patients with psoriatic arthritis ($ 23,427) and those with moderate-to-severe disease ($ 21,481). Overall, all-cause healthcare costs and outpatient pharmacy costs presented an upward trend over a 5-year period. Conclusions: Psoriasis is associated with significant economic burden, which increases over time as the disease progresses. Patients with moderate-to-severe psoriasis, those with psoriatic arthritis, or use of biologics contributes to higher healthcare costs. Psoriasis-related pharmacy expenditure is the largest driver of healthcare costs in patients with psoriasis.