The burden of palmoplantar pustulosis: A Canadian population-based study of inpatient care, emergency departments, and outpatient clinics

Background: Not much is known about the burden of palmoplantar pustulosis (PPP). Objectives: To document the burden of PPP in Canada, and to compare with psoriasis vulgaris (PV). Methods: Adult Canadians (excluding the province of Quebec) hospitalized or visiting an emergency department (ED) or hospital-/community-based clinic between April 1, 2007, and March 31, 2020, with a diagnostic code indicating PPP (ICD-10-CA: L40.3) or PV (ICD10-CA: L40.9 or L40.0) were identified using Canadian administrative data. 10-year prevalent- and 3-year incident-based approaches were conducted. Costs were determined when the most responsible diagnosis (MRD) for the admission was PPP or PV (MRD costs) and for all reasons (all-cause costs). Results: In the prevalence analysis, the 10-year mean (standard deviation [SD]) and MRD costs were $544 ($1874) for PPP and $222 ($1828) for PV (P < .01). In the incidence analysis, PPP patients had higher 3-year mean (SD) MRD costs ($1078 [$2705]) than PV ($503 [$2267]) (P < .01). All-cause costs were lower for the PPP cohort in the prevalent and incident analyses. There were no differences in all-cause inpatient mortality between PPP and PV. Limitations: Physician and prescription data were not available. Conclusion: PPP patients incurred significantly higher MRD costs than PV patients.