Epidemiology and Geographic Distribution of Generalized Pustular Psoriasis in Spain: A National Population-Based Study of Hospital Admissions from 2016 to 2020.

INTRODUCTION

Little has been published on the epidemiology of generalized pustular psoriasis (GPP). The aim of this study was to describe and analyze the geographic distribution of hospital admissions for GPP in Spain.

METHODS

We performed a cross-sectional study using the hospital discharge database of the Spanish Basic Minimum Data Set (CMBD), which is a mandatory data set of all admissions to public hospitals in the country. We included patients with a primary diagnosis of psoriasis or GPP at discharge for the period 2016 to 2020. We performed a descriptive analysis of clinical and sociodemographic characteristics of patients admitted with GPP, a spatial analysis at the province level assessing the presence of geographic heterogeneity and a GPP disease map.

RESULTS

We detected 949 diagnoses of psoriasis and 744 primary diagnoses of GPP. Mean age of patients admitted with GPP was 62.2 years. Intensive care unit admissions were ordered for 6.1% of patients and 4.8% died. The overall incidence rate of GPP among newly hospitalized patients during the study period was 3.18 cases per 1,000,000 person-years. The geographic distribution varied widely, with higher rates observed in the north-west of the country.

CONCLUSIONS

We describe the characteristics of GPP hospitalized patients in Spain and provide the first disease map for the country. The findings could help guide future research and suggest the possibility of genetic or environmental factors driving geographic differences.