Epidemiological profile and clinical outcomes of very young (<35 years) and young (35-50 years) patients with STEMI: Insights from the NORIN STEMI registry.

BACKGROUND: Despite significant progress in primary prevention, rates of myocardial infarction (MI) in South Asian population is alarmingly high.

OBJECTIVES: We sought to compare risk factor profiles and outcomes between individuals with ST-Segment Elevation Myocardial Infarction (STEMI) in young (<50 years) and old (≥50 years) age groups.

METHODS: North India STEMI Registry (NORIN-STEMI) is a prospective observational registry of patients hospitalised with STEMI. We conducted a study of young patients (<50 years) regarding their risk factors for coronary artery disease (CAD), in-hospital and 30-day mortality and compared with their older counterpart.

RESULTS: Among 5335 patients enrolled, 1752 (32.8%) were young and were 19 years younger than the older cohort. Major risk factors in young patients were physical inactivity (75.1%) and alcohol intake (67.8%). Higher prevalence of tobacco use (66.6% vs 52.4%), but lower prevalence of diabetes (16% vs 26.3%) and hypertension (18.5% vs 29.9%) were seen in young STEMI. Young patients were less likely to die both in-hospital (5.9% vs 10.0%) and at 30-days (11.1% vs 16.2%). Left ventricular ejection fraction (LVEF) < 30% at admission [OR: 8.00, 95% confidence interval (CI): 4.60-13.90, P < 0.001 in-hospital, OR: 3.92, 95% CI: 2.69-5.73 at 30-days] and female sex were strongest predictors of mortality.

CONCLUSIONS: Young STEMI patients constituted one-third of total cohort. Most of them were tobacco consumers with lesser prevalence of diabetes and hypertension. They were less likely to die both in-hospital and at 30 days because of earlier presentation to a health care facility and hence a relatively preserved LVEF.