Prevalence and Determinants of Polypharmacy: A Cross-Sectional Study Among Elderly Patients With Cardiovascular Diseases in Outpatient Clinics.

Polypharmacy, commonly defined as the concurrent use of five or more medications, is a pressing public health concern among older adults with cardiovascular disease, given its strong association with adverse drug-drug interactions, medication errors, and increased hospitalization rates. Despite its clinical significance, evidence from low- and middle-income countries, including Iran, remains limited. This study sought to determine the prevalence of polypharmacy and identify its key determinants among elderly cardiovascular patients in Kermanshah, Iran. In this cross-sectional survey of 426 participants, eligible participants were recruited using convenience sampling, and demographic, clinical, and medication-related data were collected using structured questionnaires. Statistical analyses, including chi-square tests and multivariate logistic regression, were employed to examine associations. The findings revealed that 60.1% of participants were taking five to nine medications daily. Polypharmacy was significantly associated with lower educational attainment and income, prolonged treatment duration, hospitalization history, multimorbidity, insufficient pharmacist counseling, and limited knowledge of medications and their potential adverse effects. Multivariate analysis identified the number of chronic conditions (AOR: 5.05, p < 0.001), hospitalization history (AOR: 5.15, p < 0.001), and poor medication knowledge (AOR: 6.48, p = 0.017), as independent predictors. These results highlight the urgent need for targeted, evidence-based interventions, particularly pharmacist-led counseling and patient education programs, to mitigate the burden and adverse clinical outcomes of polypharmacy, especially in resource-constrained healthcare settings.