(A-161) Hospital admissions due to adverse drug reactions and adverse drug events in older adults: A systematic review

Background: Adverse drug events (ADEs) and adverse drug reactions (ADRs) are consistently reported to be the cause of up to 30% of hospital admissions in older adults resulting in significant morbidity and mortality with an added health economic burden.

Objectives: We wish to systematically review the literature to establish the frequency of ADRs and ADEs as a cause of hospitalization with a secondary aim of determining the implicated drugs and risk factors.

Methods: Standard databases and citations were searched (2017 to 2024) and studies specifically assessing ADR and ADE prevalence and risk factors in older adults were included. The ‘strengthening the reporting of observational studies in epidemiology’ (STROBE) guidelines were used for quality assessment.

Results: Seven studies met the inclusion criteria and underwent further evaluation and quality assessment. The prevalence of ADRs was reported to be 3.3% to 23.1% and the reported prevalence of ADEs ranged from 11.75% to 18%. The median age of those included ranged from 77 to 86 years. Falls (19.4-20.9%), hypotension (7.6-33.5%), delirium (7.3-12.9%) and bleeding (8-30.2%) were the most encountered ADR/ADEs with anti-thrombotics (11.5-30.2%) diuretics (14.7-30.2%) and renin-angiotensin-aldosterone system (RAAS) inhibitors (7.5-8.9%) accounting for the highest proportion of ADR/ADE causative agents. Only two studies performed logistic regression analysis to establish risk factors for ADE/ADRs.

Conclusions: ADRs and ADEs remain a significant cause of hospital admissions in older adults despite their reported preventability. Future research into methods for risk assessment and prevention of ADEs and ADRs is urgently needed to address this significant health burden for older adults.