Polypharmacy, cardiovascular-specific medication use, and comorbidity burden among elderly residents in care homes of Colombo District, Sri Lanka: A cross-sectional study

Background Multimorbidity is a significant contemporary public health challenge globally, with older adults being disproportionately affected. This vulnerability often necessitates long-term pharmacotherapy, increasing the risk of polypharmacy. The concurrent use of multiple medications can lead to adverse health outcomes. Elderly care home residents are particularly susceptible to this risk. This study aimed to determine the prevalence and associated factors of polypharmacy, with a specific emphasis on cardiovascular medication use, in relation to comorbidity burden among elderly residents in care homes in Colombo District, Sri Lanka. Methods A descriptive, cross-sectional study was conducted among 373 elderly residents (>60 years) from ten elderly care homes in Colombo District, Sri Lanka. Participants were recruited using proportionate stratified sampling. Data were collected via a validated interviewer-administered questionnaire and a structured medication checklist. Descriptive statistics were computed for demographic and clinical variables. Group differences were analyzed using t-test, ANOVA, and Chi-square test. Multivariate logistic regression was performed to identify factors associated with polypharmacy, with statistical significance set at p<0.05. Results The mean age of the participants was 74.74 ± 7.56 years, and 75.1% were female. Multimorbidity was reported by 79.4% of residents. The most prevalent chronic condition was hypertension (75.1%). The mean number of medications per resident was 5.50 ± 2.98. The prevalence of overall polypharmacy was 59.0%, while cardiovascular-specific polypharmacy was 20.9%. Multimorbidity (AOR: 2.44, 95% CI:1.03-5.78, p = 0.043), frequent contact with a general practitioner (AOR:2.17, 95% CI:1.04-4.52, p = 0.039), and a history of myocardial infarction (AOR:3.51, 95% CI:1.10-11.17, p = 0.033) were significantly associated with polypharmacy. Cardiovascular-specific polypharmacy was independently associated with frequent hospitalization (AOR:2.83, 95% CI:1.21-6.59, p = 0.016), a history of myocardial infarction (AOR:7.26, 95% CI:2.44-21.57, p<0.001) and a history of congestive heart failure (AOR:5.20, 95% CI:1.57-17.19, p = 0.007). Conclusion The high prevalence of both overall and cardiovascular-specific polypharmacy among elderly care home residents highlights an urgent need to implement structured deprescribing initiatives and integrated, multidisciplinary geriatric care models within care homes. Priority interventions should include strengthening medication review systems, establish coordinated care pathways, and deploy targeted strategies to minimize inappropriate medication use and its associated risks.