Generalized pustular psoriasis: A nationwide population-based study using the National Health Data System in France

Area of Science:

• Dermatology
• Epidemiology
• Real-world evidence

Background:

• Generalized pustular psoriasis (GPP) is a rare, chronic neutrophilic skin disease.
• Limited real-world data exists on GPP flares and their impact on disease progression and morbidity.
• Understanding GPP patient characteristics is crucial for effective management.

Purpose of the Study:

• To characterize clinical features, comorbidities, and epidemiology of GPP patients.
• To analyze the frequency and severity of GPP flares.
• To compare GPP patients with a matched severe psoriasis population.

Main Methods:

• Population-based real-world cohort study using the French national health database (SNDS).
• Algorithm developed to identify GPP flares.
• Prevalent (2010-2018) and incident (2012-2015) GPP cohorts established.
• Propensity score matching used to compare GPP incident cohort with severe psoriasis cohort.

Main Results:

• Prevalent and incident GPP cohorts included 4195 and 1842 patients, respectively (mean age 58 years, 53% male).
• GPP patients exhibited significantly higher rates of comorbidities (hypertension, ischemic heart disease, hyperlipidaemia) than severe psoriasis patients.
• Flare rate was 0.1 flares/person-year; hospitalized flares (569 patients) involved mean 11.6-day stays, with 25% ICU admission.
• Cumulative incidence and prevalence of GPP in 2017 were 7.1 and 45.2 per million, respectively.

Conclusions:

• GPP patients possess a distinct comorbidity profile compared to severe psoriasis patients.
• GPP flares are associated with significant morbidity, evidenced by prolonged hospitalizations and ICU admissions.
• Real-world data provides critical insights into GPP burden and patient characteristics.