P116 Differential risk of incident and recurrent erythrodermic psoriasis in patients receiving systemic therapies: cohort analyses from the British Association of Dermatologists Biologics and Immunomodulators Register

Abstract

Erythrodermic psoriasis (EP) is a severe variant of psoriasis affecting > 90% of the skin. It is unknown whether systemic therapies used for psoriasis differentially affect the risk of EP. This study aimed to investigate whether biologics are associated with a reduced risk of incident or recurrent EP relative to nonbiologic systemic therapies. Data from the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR) were analysed. Participants received either nonbiologic (acitretin, apremilast, ciclosporin, deucravacitinib methotrexate, dimethyl fumarate) or biologic systemics [inhibitors of tumour necrosis factor, interleukin (IL)-17, IL-12/23 or IL-23]. Inverse probability of treatment weighting based on propensity scores was used for confounder adjustment. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident and recurrent EP. Sensitivity analyses included implementing a 30-day lag time (events starting within 30 days of a treatment cessation or switch were assigned to the previous exposure) and adjustment for combination therapy. Of the 13 637 patients with no history of EP at registration, 36 developed incident EP during 97 402 person-years of follow-up (incidence rate 0.36 per 1000 person-years, 95% CI 0.26–0.52). Risk of incident EP was lower with biologics than nonbiologics (HR 0.32, 95% CI 0.14–0.73). After introducing a lag time and adjusting for concomitant use of nonbiologic systemics, the risk lowered further (HR 0.16, 95% CI 0.07–0.37). Of the 2505 patients with a history of EP at registration, 50 developed at least one further EP episode during 19 629 person-years (incidence rate 2.61 per 1000 person-years, 95% CI 1.66–3.17). Risk of recurrent EP was lower with biologics than nonbiologics (HR 0.47, 95% CI 0.22–0.99), with minimal change after including a lag time and adjusting for concomitant treatment (HR 0.50, 95% CI 0.23–1.10). The risk of new onset or recurrence of EP is lower in those receiving biologics than nonbiologics. This supports preferential use of biologics in those at risk of or presenting with EP. Further research with a higher number of EP events is required to validate these findings.