SG10 (P058) The epidemiology of epidermolysis bullosa in England, 1997–2024: a retrospective national cohort study

Abstract Epidermolysis bullosa (EB) comprises a group of rare genetic blistering disorders with variable severity. Epidemiological studies on EB have previously often relied on data from specialist centres. However, many patients are managed outside of this setting. This national retrospective cohort study identified all cases of EB in England from April 1997 to April 2024 using International Classification of Diseases 10th Revision code Q81. Records were obtained from NHS England’s national Hospital Episode Statistics (HES) inpatient and outpatient data and data from the National Congenital Anomaly and legacy regional congenital anomaly registers. Cases were linked to primary care prescription data from the National Health Service Business Services Authority and mortality data from the Office for National Statistics. Crude counts and point prevalence per million in 2023 in England were calculated. Patient sociodemographic factors, treatments, prescriptions and mortality rates were described. In total, 3419 patients with EB were identified, of whom 2980 were alive as of June 2023, resulting in a prevalence of 51.7 per million [95% confidence interval (CI) 49.8–53.5]. The most common subtype was unspecified EB (n = 1442), with a prevalence of 25.0 per million (95% CI 23.7–26.3), followed by EB simplex (n = 765; prevalence 13.3, 95% CI 12.3–14.2), dystrophic EB (n = 512; prevalence 8.9, 95% CI 8.1–9.7), other EB (n = 235; prevalence 4.1, 95% CI 3.6–4.6) and severe junctional EB (n = 26; prevalence 0.5, 95% CI 0.3–0.7). Overall, 66% of patients identified as White ethnicity, followed by 10% as Asian ethnicity; however, 18% had missing ethnicity data. Female patients comprised 54% of cases. In total, 21% lived in areas of the lowest deprivation, compared with 16% in the quintile of the most deprived population. During the follow-up 481 of 3419 (14%) patients died, and 4.6% died before age 15 years, with severe junctional EB showing a median age at death of < 6 months. In the last 5 years of data, 123 of 160 (76.9%) patients underwent upper gastrointestinal tract procedures. Analysis of the community prescriptions dataset showed that 819 915 items (412 882 prescriptions) were issued from April 2018 to September 2024. Of these, 23.4% were dressings, followed by 14.8% central nervous system and 9.4% cardiovascular system medications, amounting to a total prescription cost of £62.2 million. The annual median cost per patient (2019–2023) was £244 (interquartile range £55.20 to £1027), which was highest in patients with dystrophic EB (median £735, interquartile range £152 to £6145). This is the first population-level study of EB and presents the largest and most comprehensive national EB dataset reporting prevalence, demographics and treatments for EB. It highlights the utility of national datasets in understanding rare conditions and supporting improvements in patient care.