Clearance of Psoriasis: The Impact of Private Versus Public Insurance
February 2015 | Volume 14 | Issue 2 | Original Article | 119 | Copyright © February 2015
Catherine D. Buzney MA,a Caitlin Peterman BS,a Ami Saraiya MD,b Shiu-chung Au MD,b
Nicole Dumont,b Ryan Mansfield AS,b and Alice B. Gottlieb MD PhDa,b
aTufts University School of Medicine, Boston, MA
bDepartment of Dermatology, Tufts Medical Center, Boston, MA
METHODS: 258 subjects were included from a database of psoriasis patients seen at Tufts Medical Center (Boston, MA) during 2008-2014. Insurance was classified as primarily private or public (Medicare or MassHealth/Medicaid). Patients required a minimum of two consecutive visits per treatment and at least 8 weeks within one of four treatment categories: biologics, oral systemics/ phototherapy, combined biologics and oral systemics/phototherapy, or topicals only. Primary endpoint was the Simple-Measure for Assessing Psoriasis Activity (S-MAPA) calculated by multiplying Physician Global Assessment by Body Surface Area. S-MAPA<3 constituted absolute clearance. Insurance type was evaluated as a predictor of prescribed treatment categories, maximum S-MAPA
improvement from baseline, and total drugs used per treatment course (“drug-switching”).
RESULTS: 80.2% (n=207) and 19.8% (n=51) had primarily private and public insurance, respectively. 69.6% with private insurance were prescribed biologics versus 66.7% (public insurance) (P=0.689). 54% (private) versus 49% (public) achieved clearance (P=0.514). However, S-MAPA decreased 78.35% from baseline in those with private insurance compared to 61.48% (public) (P=0.036). On average, privately insured patients used at least twice as many same-category treatments, most commonly biologics, than publicly insured individuals (P=0.003). Drug-switching was significantly associated with clearance (P=0.024). Multivariate analysis demonstrated no significant differences in prescribed treatment categories, drug efficacy, clearance, S-MAPA, or drugswitching with respect to patient age.
CONCLUSIONS: Treatment categories were comparably prescribed between insurance subgroups. However, privately insured patients achieved significantly greater degrees of clearance and switched between more medications within biologic and systemic categories, potentially explaining their overall improved therapeutic response. Further studies including cost-analysis could clarify any difference in the effectiveness of prescribed therapy for these two patient populations.
J Drugs Dermatol. 2015;14(2):119-125.