Increasing the reporting of adverse drug reaction‐related hospitalizations using an ICD‐10‐based identification workflow: A multicentre study from Switzerland

BACKGROUND: Reporting adverse drug reactions (ADRs) is essential for drug safety. In Switzerland, healthcare professionals are legally required to report serious and unlabelled ADRs, yet under-reporting remains widespread. We tested a novel method to increase reporting of ADR-related hospitalizations. METHODS: This retrospective observational study used ADR-indicative ICD-10 codes to screen admissions to four Swiss hospitals, identify suspected drugs and send individual case safety reports (ICSRs) of confirmed cases to Swissmedic. RESULTS: Participating hospitals previously reported ~18 ICSRs annually. During the study period (7/2023-12/2023), 200 ADR-related hospitalizations were reported following a review of 814 pre-filtered admissions. Most ICSR data were available in structured format: Median age of patients was 59 (interquartile range [IQR] 42-75); 87 (44%) males; median of two comorbidities (IQR 1-3); the three most frequent ADRs were 'K52.1 Toxic gastroenteritis and colitis' (11 [6%]), 'T42.4 Poisoning by benzodiazepines' (10 [5%]) and 'R11 Nausea and vomiting' (10 [5%]). Discharge reports contained free-text information on suspected drugs: More than half of ADR-related hospitalizations were caused by antineoplastics (45 [23%]), psycholeptics (38 [19%]), opioids and other analgesics (34 [17%]). The median time to screen a case was 1 min, 8 min to collect, compile and send data of confirmed cases. CONCLUSION: The approach successfully increased reporting of serious ADRs. The time investment for creating ICSRs might soon be rendered obsolete, as most data are available in structured format, and large language models are key to identifying suspected drugs in discharge reports.