[Adverse Drug Events in Hospitalized Patients in Chile: Prevalence & Implications].

Objective: To study the prevalence of adverse drug events (ADE) in hospitalized patients in Chile. As part of our research, we also assessed the validity of the method used to identify the occurrence of an ADE based on the discharge diagnoses of the patient.

Design: The study included 1,7 million patients hospitalized during 2019-2020. We analyzed the following variables for each patient: ICD-10 discharge diagnoses, sociodemographic information, and clinical outcome indicators, i.e., diagnosis-related group (DRG) weight, length of stay, and mortality. To validate the method for the identification of ADEs, first, we generated a random representative sample of patients, stratified by sex and medical specialty, hospitalized in a Chilean public hospital in 2019, and then we compared the outcome of the method with the opinion of a group of clinical experts that reviewed each patient's discharge summary retrospectively.

Results: The prevalence of ADEs in hospitalized patients in Chile during 2019 and 2020 was 2,7% and 3,1%, respectively. The precision of the method used to identify ADEs was 83,3% or higher (CI 90%).

Conclusions: This paper uses nationwide data to describe the prevalence of ADEs and their correlation with different factors associated with the patient, the patient's disease, and the health service. These studies are essential to designing public health policies that effectively address healthcare quality and patient safety.