Applicability and Risk Stratification of QRISK®, Framingham Risk Score, Systematic Coronary Risk Evaluation (SCORE), and American College of Cardiology/American Heart Association (ACC/AHA) Risk Assessment Tools Among Patients in Taif, Saudi Arabia

Introduction Cardiovascular disease (CVD) is the leading cause of death globally and continues to pose significant challenges to public health in Saudi Arabia. Risk prediction tools are essential in guiding preventive strategies, yet their accuracy may vary across populations. This study aimed to assess and compare the applicability, which was based on the availability of all required variables, and the risk stratification performance of four cardiovascular risk assessment tools, such as the Framingham Risk Score (FRS), American College of Cardiology/American Heart Association (ACC/AHA) Atherosclerotic Cardiovascular Disease (ASCVD) Risk Estimator, Systematic Coronary Risk Evaluation (SCORE), and QRISK®, among Saudi patients diagnosed with acute coronary syndrome (ACS). Methods A retrospective cross-sectional study was conducted at Alhada Armed Forces Hospital in Taif, Saudi Arabia, including all Saudi patients aged 18 years and older who were diagnosed with either a first or second myocardial infarction (MI) between January 2020 and January 2025. Data were collected through patient interviews and electronic medical records to retrospectively reconstruct the cardiovascular risk profile prior to the first MI event. Risk scores were calculated using the four tools, and each tool's applicability was based on the availability of all required variables. Statistical analyses were performed to assess tool applicability, risk stratification, and correlations among the tools. Results A total of 65 patients were included, with a mean age of 61 ± 13 years and a mean BMI of 29.9 ± 4.5 kg/m². The majority were male (76.9%), and common comorbidities included hypertension (49.2%), chronic kidney disease (10.8%), and atrial fibrillation (12.3%). QRISK® had the highest applicability (98.5%), followed by FRS (86.2%), ACC/AHA ASCVD Risk Estimator (73.8%), and SCORE (66.2%). SCORE identified the highest proportion of high-risk patients (24.3%), followed by QRISK® (21.6%) and FRS (13.5%). Strong-to-very strong correlations were observed between the tools, especially between QRISK® and ACC/AHA ASCVD Risk Estimator (r = 0.937) and QRISK® and FRS (r = 0.905). Conclusion QRISK® showed the highest applicability in this cohort; however, applicability does not reflect predictive accuracy. As these tools were designed for primary prevention, their use in post-MI patients may overestimate risk. Variability in high-risk classifications by the tools could affect preventive decisions. These findings underscore the need for further validation in larger, prospective, primary prevention studies within the Saudi population.