Background: India has the highest burden of acute coronary syndromes in the world, yet little is known about the treatments and outcomes of these diseases. We aimed to document the characteristics, treatments, and outcomes of patients with acute coronary syndromes who were admitted to hospitals in India.
Methods: We did a prospective registry study in 89 centres from 10 regions and 50 cities in India. Eligible patients had suspected acute myocardial infarction with definite electrocardiograph changes (whether elevated ST [STEMI] or non-STEMI or unstable angina), or had suspected myocardial infarction without ECG changes but with prior evidence of ischaemic heart disease. We recorded a range of clinical outcomes, and all-cause mortality at 30 days.
Findings: We enrolled 20,937 patients. Of the 20,468 patients who were given a definite diagnosis, 12,405 (60.6%) had STEMI. The mean age of these patients was 57.5 (SD 12.1) years; patients with STEMI were younger (56.3 [12.1] years) than were those with non-STEMI or unstable angina (59.3 [11.8] years). Most patients were from lower middle 10,737 (52.5%) and poor 3999 (19.6%) social classes. The median time from symptoms to hospital was 360 (IQR 123-1317) min, with 50 (25-68) min from hospital to thrombolysis. 6226 (30.4%) patients had diabetes; 7720 (37.7%) had hypertension; and 8242 (40.2%) were smokers. Treatments for STEMI differed from those for non-STEMI or unstable angina. More patients with STEMI than with non-STEMI were given anti-platelet drugs (98.2%vs 97.4%); angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARB) (60.5%vs 51.2%); and percutaneous coronary interventions (8.0%vs 6.7%, p<0.0001 for all comparisons). Thrombolytics (96.3% streptokinase) were used for 58.5% of patients with STEMI. Conversely, fewer patients with STEMI than those with non-STEMI or unstable angina were given beta blockers (57.5%vs 61.9%); lipid-lowering drugs (50.8%vs 53.9%); and coronary bypass graft surgery (1.9%vs 4.4%, p<0.0001 for all comparisons). The 30-day outcomes for patients with STEMI were death (8.6%), reinfarction (2.3%), and stroke (0.7%). Outcomes for those with non-STEMI or unstable angina were better: death (3.7%), reinfarction (1.2%), and stroke (0.3%, p<0.0001 for all comparisons). Use of key treatments also differed by socioeconomic status: more rich patients than poor patients were given thrombolytics (60.6%vs 52.3%), beta blockers (58.8%vs 49.6%), lipid-lowering drugs (61.2%vs 36.0%), ACE inhibitors or ARB (63.2%vs 54.1%), percutaneous coronary intervention (15.3%vs 2.0%), and coronary artery bypass graft surgery (7.5%vs 0.7%, p<0.0001 for all comparisons). Mortality was higher for poor patients than for rich patients (8.2%vs 5.5%, p<0.0001). Adjustment for treatments (but not risk factors and baseline characteristics) eliminated this difference in mortality.
Interpretation: Patients in India who have acute coronary syndromes have a higher rate of STEMI than do patients in developed countries. Since most of these patients were poor, less likely to get evidence-based treatments, and had greater 30-day mortality, reduction of delays in access to hospital and provision of affordable treatments could reduce morbidity and mortality.