Identification of Adverse Drug Events The Use of ICD-10 Coded Diagnoses in Routine Hospital Data

Background: Adverse drug events (ADE) are a common cause of hospital admission as well as a common complication of inpatient care. The current reporting systems in Germany are of only limited use for the identification of ADE. The aim of this study is to examine the potential usefulness of ICD-10 coded diagnoses in routine hospital data for the identification of ADE. Methods: The common, major manifestations of ADE were mapped to the ICD-10-GM, and categories in the ICD-10-GM for which a possible causal relationship with medications is explicitly mentioned were included as well. A total of 505 relevant ICD-10-GM codes were identified. An evaluation was carried out on the basis of an aggregated data set from eleven million inpatients treated in 2006. Results: 0.7% of hospital admissions were revealed by routine data to be causally related to the administration of a drug. In 5.3% of admissions, there was at least a reason to suspect such a causal relation. Furthermore, one of the 505 relevant codes was found to be present in 9.0% of the secondary diagnoses. Conclusions: The available ICD-10-GM codes for manifestations of ADE are used in routine hospital data in Germany. Their usefulness for the identification of ADE should be better exploited. Our results and other relevant published literature imply that this procedure will result in both false-positive and false-negative findings, which will have to be taken into account as well.