Serious infection risk in children with psoriasis on systemic treatment: a propensity score matched population-based study
Background: Psoriasis (PsO) is increasingly treated with systemic medications, yet their safety is not well characterized in children. Objective: We sought to estimate the 6-month risk of serious infections in children with PsO treated with biologics, systemic non-biologics and phototherapy. Methods: Using insurance claims data, we identified children <18 years with PsO and compared the frequency of serious infections in those initiating biologics, systemic non-biologics, and phototherapy. Relative risks (RR) were estimated before and after 1:1 propensity-score matching. Results: Among 57,323 children with PsO, the 6-month risk of infection was 4.2 per 1,000 patient-years in 722 biologic initiators, 5.1 in 988 systemic non-biologic initiators, and 1.1 in 2,657 phototherapy initiators. The RR of infection in biologics vs. non-biologics was 0.67 (0.11, 3.98), in biologics vs. phototherapy was 1.50 (0.25, 8.95) and in non-biologics vs. phototherapy was 5.00 (0.59, 42.71). The background risk of infection in children with PsO was 1 per 1,000, almost double the risk compared to children without PsO (RR=1.84; 1.15, 1.97). Conclusions: We found no meaningful difference in infection risk between biologics vs. non-biologics, and no robust difference between systemic users vs. phototherapy. Independent of treatment, children with PsO had a higher risk of infection than those without PsO.