Can QRISK-3 and PREVENT Predict Premature Acute Coronary Syndrome in Adults under 40 Years? The Insights from Predicting the Risk of Acute Coronary Syndrome under 40 (PRACS-40) Study

Background: The occurrence of acute coronary syndrome (ACS) among individuals under 40 years has increased markedly, yet current atherosclerotic cardiovascular disease risk prediction models are primarily validated in older adults, leading to underrecognition of risk and missed prevention in the young. Objectives: The objectives of this study were to evaluate cardiovascular risk factors (CVRFs) in young adults with ACS and to assess the applicability and correlation of QRISK-3 and PREVENT risk prediction scores in this demographic. Methods: In this single-center observational study, 250 patients (<40 years of age) with ACS were assessed for the CVRFs; demographic, metabolic, and lifestyle profiles, echocardiographic and coronary angiographic (CAG) findings; and risk scores. The correlation between QRISK-3 and PREVENT models was assessed in the 30–40-year age subgroup. Results: The cohort (mean age: 35.1 ± 4.0 years; 93.2% of males) demonstrated a high prevalence of tobacco use (smoking – 40.8% and smokeless tobacco – 76.8%) and diabetes (26.8%). ST-segment-elevated myocardial infarction represented 63.6% of cases, and single-vessel disease predominated on CAG. The mean QRISK-3 10-year and 30-year estimates were 1.53+1.64 and 11.76+7.21, respectively. A strong correlation was observed between QRISK-3 and PREVENT for both 10-year ( r = 0.714, P < 0.001) and 30-year ( r = 0.868, P < 0.01) risk estimates in the 30–40-year age group. Smokeless tobacco users exhibited shorter sleep duration and lower 30-year QRISK scores compared with nonusers ( P < 0.001) Conclusions: Premature ACS links to modifiable factors such as tobacco and poor lifestyle. Standard models underpredict short-term risk but align well with long-term; integrating lifetime estimates and region-specific behaviors (e.g., smokeless tobacco) could improve prediction and enable earlier interventions.