Utility of Serum Homocysteine and Lipoprotein(a) in Acute Coronary Syndrome: A Cross-Sectional Study From Western India

Background: Acute coronary syndrome (ACS) remains a major cause of cardiovascular morbidity and mortality in India, with disease onset occurring at younger ages than in Western populations. Serum homocysteine and lipoprotein(a) Lp(a) are recognized non-conventional risk factors whose interrelationship and age-specific relevance in Indian patients with ACS remain poorly defined. Methods: This cross-sectional study was undertaken at Dr. Sampurnanand Medical College and Mathura Das Mathur Hospital, Jodhpur, between January and November 2023. Seventy-five consecutive ACS patients (ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina) were enrolled. Serum homocysteine and Lp(a) were measured by immunoturbidimetry, with Lp(a) ≥30 mg/dL defined as elevated. Receiver operating characteristic (ROC) curve analysis was performed to identify the optimal homocysteine threshold for predicting young-onset ACS. Results: Younger patients (aged below 40 years) demonstrated significantly higher homocysteine levels than older counterparts (p=0.0009). Elevated Lp(a) was present in nearly half the cohort and was accompanied by significantly higher homocysteine concentrations (p<0.0001). Vitamin B12 deficiency was identified in over half of the patients, potentially contributing to hyperhomocysteinaemia. Conclusion: Serum homocysteine is markedly elevated in young-onset ACS and correlates positively with Lp(a) levels. These findings suggest that screening for both biomarkers, alongside vitamin B12 assessment, may warrant consideration in the workup of ACS patients, particularly in the Indian population. However, given the cross-sectional, single-center design of the present study and the absence of outcome data, prospective multicenter studies are needed to validate these associations.