The Extent of Medication-Related Hospital Admissions in Australia: A Review from 1988 to 2021

Introduction Medication-related problems often lead to patient harm. This paper aims to review the Australian literature to determine the overall incidence, severity and preventability of medication-related hospital admissions, as well as providing a national estimate on their extent and cost. Methods The first part of the paper includes a literature search to identify studies that provided estimates of medication-related problems that caused hospital admissions. Incidence of medication-related hospital admissions, type of medication-related problem contributing to admission (e.g. adverse medicine reaction) and method used to estimate incidence (e.g. chart review) were extracted. Data on severity and preventability of the admissions were extracted where available. The second part of the paper involves use of methodological triangulation to estimate the extent and cost of medication-related hospital admission. Median estimates used to assess medication-related hospital admissions and the 2019–2020 national hospital admissions data were used to calculate the national estimate on the extent of medication-related hospital admission. Costs were also estimated. Results Seventeen studies provided estimates on the extent of medication-related hospital admissions as assessed using medication chart review. The median incidence of 2.5% (interquartile range [IQR] 0.6%) as a proportion of all hospital admissions suggests 275,000 hospital admissions annually in Australia are medication related. The median incidence of 9% (IQR 3.9%) of emergency admissions suggests that 270,000 admissions annually are medication related. Eight studies provided estimates of the extent of medication-related hospital admissions identified from administrative health data; the median incidence of 1.7% with an under-reporting rate of 82% suggests 280,000 hospital admissions annually are medication related. Triangulation of results suggests that at least 250,000 hospital admissions annually in Australia are medication related, with an estimated cost of 1.4 billion Australian dollars (AUD$). Five studies assessed severity, and nine studies assessed preventability. Preventability estimates suggest two-thirds of medication-related hospital admissions are potentially preventable. Conclusions We estimated that 250,000 hospital admissions in Australia are medication related, with an annual cost of AUD$1.4 billion to the healthcare system. Two-thirds of medication-related hospital admissions are potentially preventable.