Incidence, In-Hospital and Long-Term Mortality, and Sequelae of Epidermal Necrolysis in Adults.

Importance: The incidence of epidermal necrolysis (EN), including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), varies across studies. While in-hospital mortality rates range from 15% to 20%, contributors to long-term mortality have been rarely evaluated and remain unknown.

Objective: To assess the incidence of and compare factors associated with in-hospital mortality and postdischarge mortality and sequelae among patients with EN.

Design, setting, and participants: This cohort study used French Health System data from January 1, 2013, to December 31, 2022, and included all adult patients (aged ≥18 years) with EN identified using International Statistical Classification of Diseases, Tenth Revision codes combined with a validated algorithm.

Exposure: Epidermal necrolysis.

Main outcomes and measures: Incidence, in-hospital mortality, postdischarge mortality, and sequelae were assessed as main outcomes. Factors associated with mortality were assessed using a multivariable Cox proportional hazards model.

Results: A total of 1221 adult patients with EN (median [IQR] age, 66 [49-79] years; 688 females [56.3%]) were included. Incidence was 2.6 (95% CI, 2.5-2.7) cases per million person-years. The in-hospital mortality rate was 19% (95% CI, 17%-21%) and postdischarge mortality rate, 15% (95% CI, 13%-17%) for an overall mortality of 34% (95% CI, 31%-36%). In multivariable analysis, factors associated with in-hospital mortality were age (adjusted hazard ratio [AHR], 1.03 per year of age; 95% CI, 1.02-1.04 per year of age), history of cancer (AHR, 2.04; 95% CI, 1.53-2.72), dementia (AHR, 1.85; 95% CI, 1.12-3.07), liver disease (AHR, 1.81; 95% CI, 1.24-2.64), and EN severity (TEN vs SJS: AHR, 2.14; 95% CI, 1.49-3.07). Cancer, liver disease, and dementia remained associated with postdischarge mortality (AHR, 3.26 [95% CI, 2.35-4.53], 1.86 [95% CI, 1.11-3.13], and 1.95 [95% CI, 1.11-3.43], respectively). Conversely, EN initial severity was not associated with mortality after hospital discharge (TEN vs SJS: AHR, 0.95; 95% CI, 0.60-1.47), but acute complications remained associated (AHR, 2.14 [95% CI, 1.26-3.63] and 2.44 [95% CI, 1.42-4.18] for acute kidney injury and sepsis, respectively). The main sequelae were ophthalmologic and mood disorders.

Conclusion: The findings of this cohort study suggest that although EN is a rare condition, it is associated with high rates of in-hospital and postdischarge mortality among patients who are older and have comorbid conditions. However, in contrast with in-hospital mortality, postdischarge mortality is not associated with EN initial severity but with acute in-hospital complications (eg, acute kidney injury and sepsis). Future studies are needed to construct models to estimate long-term outcomes and sequelae in patients with EN.