Association Between Polypharmacy and Hospital Readmissions in Elderly Patients with Cardiovascular Disease

Abstract

Background: Multiple chronic conditions render polypharmacy prevalent among elderly people with cardiovascular disease (CVD). This study examines the correlation between polypharmacy and hospital readmissions in older cardiovascular patients, focusing on adverse drug reactions (ADRs), drug-drug interactions (DDIs), and medication adherence. Objectives: To ascertain polypharmacy in elderly cardiovascular disease patients, investigate its correlation with hospital readmissions, evaluate the impact of adverse drug reactions and drug-drug interactions, and identify issues related to adherence and mortality risks associated with polypharmacy.  Methodology: A cross-sectional study was conducted at the Dhi Qar General Hospital in Iraq from September to December 2024. They enlisted 400 patients aged 65 and older with a verified diagnosis of cardiovascular disease (CVD). Polypharmacy denotes the concurrent use of five or more medications. We retrieved demographic data, clinical information, prescription details, and hospital readmission statistics from medical records at 30, 90, and 180 days post-discharge. we conducted logistic regression analysis on polypharmacy, readmission, adverse drug reactions (ADRs), drug-drug interactions (DDIs), and mortality, controlling for potential confounders. Results: The results showed that polypharmacy affected half of the 400 patients. Readmission rates for polypharmacy patients significantly above those of non-polypharmacy patients at 30 days (20% vs 12%), 90 days (35% vs 20%), and 180 days (50% vs 30%) (p < 0.05). Patients using polypharmacy had elevated rates of adverse drug reactions (30%) and drug-drug interactions (25%), along with increased readmission occurrences. Patients using polypharmacy exhibited poorer adherence rates (60%) compared to those not on polypharmacy (80%), along with elevated rates of readmission and mortality. Patients experiencing polypharmacy exhibited a higher mortality rate at 180 days (15%) compared to 8% (p< 0.05).  Multivariate research established polypharmacy as an independent predictor of hospital readmission and mortality. Conclusion: Polypharmacy is linked to much higher rates of hospital readmission, adverse drug reactions (ADRs), drug-drug interactions (DDIs), not taking medications as prescribed, and death in older people with cardiovascular disease (CVD). These findings suggest that we should implement routine medication evaluations, the cessation of unnecessary medications, and adherence interventions to mitigate polypharmacy risks in this particularly susceptible demographic.