Survival and predictors of major adverse cardiovascular events among patients with acute coronary syndrome in Ethiopia: a retrospective cohort study

Abstract

OBJECTIVES: To determine the time to major adverse cardiovascular events (MACE) and identify its predictors among patients with acute coronary syndrome (ACS) discharged on secondary prevention medications in Ethiopia. DESIGN: Institution-based retrospective cohort study. SETTING: University of Gondar Comprehensive Specialized Hospital, Northwest, Ethiopia. PARTICIPANTS: A total of 400 adult patients diagnosed with ACS and discharged with secondary prevention medications between January 2020 and December 2024. OUTCOME MEASURES: The primary outcome was time to first MACE, defined as reinfarction, stroke or heart failure, measured in years from hospital discharge. A Cox proportional hazards regression model was fitted to identify predictors of time to develop MACE. Data collected from patient medical charts were exported to STATA V.17 for analysis. The log-rank test was used to determine the survival difference between subgroups of participants. RESULTS: During follow-up, 33.8% of patients experienced at least one MACE. The median time to MACE was 1.5 years. Female sex (adjusted HR (AHR)=2.08; 95% CI 1.24 to 3.49), presence of chronic comorbidities (AHR=2.09; 95% CI 1.42 to 4.41) and higher Killip class (IV vs I: AHR=1.57; 95% CI 1.22 to 1.78) were independently associated with a shorter time to MACE. Patients aged ≤55 years had a lower risk of MACE compared with those aged ≥66 years (AHR=0.77; 95% CI 0.54 to 0.98). CONCLUSIONS: Among patients with ACS discharged on secondary prevention medications, one-third experienced MACE within a median of 1.5 years. Older age, female sex, presence of comorbidities and higher Killip class were significant predictors of shorter time to MACE. These findings highlight the need for targeted postdischarge monitoring and secondary prevention strategies, particularly in resource-limited settings.