Prevalence of risk factors and their associations for Acute Coronary Syndrome among patients admitted to secondary and tertiary care hospitals in Kalutara district of Sri Lanka- a lower–middle-income country

Background: Acute coronary syndrome (ACS) arises from reduced coronary blood flow causing myocardial injury and is driven by both non-modifiable and modifiable risk factors. In low- and middle-income countries, ACS is a leading cause of adult mortality with an increasing burden of cardiovascular risk factors. This study aimed to assess the prevalence, distribution, and associations of ACS risk factors among patients admitted to secondary and tertiary care hospitals. Methods: A descriptive cross-sectional study was conducted among adult patients admitted with Acute Coronary Syndrome (ACS) to secondary and tertiary care hospitals in the Kalutara District, Sri Lanka, from December 2021 to January 2022. Patients aged ≥18 years with STEMI, NSTEMI, or unstable angina were consecutively recruited. Data were collected using a pre-tested, validated interviewer-administered questionnaire on socio-demographic characteristics and cardiovascular risk factors. Descriptive statistics and chi-square tests were used, with 5% statistical significance level. Results: Response rate was 91%. The mean age was 61.7 years, and the majority(62.5%) were males. Non-ST elevation myocardial infarction was the most frequent(41.9%) diagnosis, followed by ST elevation myocardial infarction(36.8%) and unstable angina (21.3%). High blood pressure(50.8%), diabetes mellitus(43.2%), and elevated blood lipids (39.8%) were the most prevalent risk factors. Around 30% were current or recent smokers, and 24.5% with a family history of coronary disease. Increasing age was significantly associated with high blood pressure(P=0.005), diabetes(P=0.042), and smoking(P=0.002). Smoking showed a strong association with ST elevation myocardial infarction (P=0.011), while elevated lipids were more common among non-ST elevation cases(P=0.011). A lower level of education was significantly related to high blood pressure(P=0.005). Despite good knowledge of risk factors among patients, no significant association was found between knowledge level and risk factors. Conclusion: Acute coronary syndrome in Sri Lanka is largely influenced by modifiable risk factors—particularly high blood pressure, diabetes, lipid abnormalities, and smoking. Although awareness of these factors was high, behavioural change was inadequate. Comprehensive, community-based prevention and lifestyle interventions are essential to reduce the burden of Acute Coronary Syndrome.