Our objective was to determine the percentage of opioid overdose events among medical and surgical inpatient admissions, and to identify risk factors associated with these events.
We searched PubMed and CINAHL databases from inception through July 30, 2017 and identified additional studies from reference lists and other reviews. Articles were included if they reported original research on the rate of opioid overdoses or opioid-related adverse events, and the adverse events occurred in a general medical hospital during an inpatient stay. We extracted information on study population, design, results, and risk for bias using the Newcastle-Ottawa Quality Assessment Scale. We performed this review in accordance with recently suggested standards and report our findings as per the Meta-Analyses and Systematic Reviews of Observational Studies guidelines.
Thirteen studies met our eligibility criteria. The percentage of opioid overdoses ranged from 0.06% to 2.50% of hospitalizations. The majority of studies used only 1 method of event detection. Risk factors for overdose included older age, infancy, medical comorbidity, substance use disorder diagnosis, combining opioids with other sedatives, and admission to hospitals with higher opioid-prescribing rates.
Opioid overdose in the inpatient setting is a serious preventable harm and is likely underestimated in much of the current literature. Improved detection methods are needed to more accurately measure the rate of inpatient opioid overdose. Refined estimates of opioid overdose should be used to drive safety and quality improvement initiatives in hospitals.