Evaluating immunotherapy-related adverse events reporting in the French national hospital discharge database (PMSI): a pilot study

This work aims to support real-world studies of immunotherapy-related adverse events (irAEs). Our objective was to examine whether severe irAEs could be identified in the PMSI, using data collected as part of the Registry of Severe Adverse Reactions to Immunomodulatory Antibodies used in Oncology (REISAMIC). For this retrospective, single-center study, we included all irAEs that required hospitalization reported in REISAMIC in patients managed at Gustave Roussy (GR) between December 2013 and March 2021. We first linked REISAMIC data to GR's PMSI data and then reviewed all the International Classification of Diseases-10 (ICD) codes of diagnosis assigned at discharge to identify irAEs. If no ICD code reflecting an irAE was found in GR's PMSI, patient medical records were consulted to explore whether the patient was hospitalized at a different hospital. Of the 173 irAEs requiring an hospitalization that occurred in 151 patients, 81 (46.8 %) were coded with at least one irAE-related ICD code in the PMSI. Of note, an associated ICD code Y43 indicating the presence of a drug-related adverse event was found in only 30 cases. For the remaining 92 irAEs for which no ICD code was found in the GR's PMSI, a manual review of the medical records revealed that 71 (41 %) were treated at a different hospital and therefore could not be evaluated in our study, 15 (8.7 %) were untraced in the medical record, and only 6 (3.5 %) were reported in the medical record but not coded. irAEs leading to hospitalization reported in REISAMIC appear well coded in GR's PMSI. Despite the inherent limitations of single-center studies, this is an encouraging result for future research on severe irAE using the French national health data system (SNDS). Immunotherapy related adverse events ; Immunotherapy ; PMSI Les auteurs déclarent ne pas avoir de liens d'intérêts.