Myocardial Infarction Without Standard Modifiable Risk Factors From 2025-2040

BACKGROUND: Standard modifiable risk factors (SMuRFs) are associated with increased risk of acute myocardial infarction (AMI). Patients with AMI in the absence of standard modifiable risk factors (SMuRF-less) have demonstrated excess mortality. OBJECTIVES: The study aims to forecast trends in prevalence and case fatality of SMuRF-less AMI in Singapore and United Kingdom. METHODS: Data from the Singapore Myocardial Infarction Registry and the UK Myocardial Ischemia National Audit Project were used to construct Poisson regression models to predict the prevalence and case fatality rate of SMuRF-less AMI from 2025 to 2040. RESULTS: From 2025 to 2040, SMuRF-less AMI cases are expected to contribute to larger proportions of total AMI cases in Singapore (5.8% [95% CI: 5.2%-6.4%] to 8.5% [95% CI: 6.2%-10.8%]) and United Kingdom (13.8% [95% CI: 13.0%-14.6%] to 16.9% [95% CI: 15.1%-18.7%]). The proportion of SMuRF-less AMI mortality of the total AMI mortality is set to decrease in the United Kingdom (11.3% [95% CI: 10.5%-12.1%] to 9.5% [95% CI: 7.7%-11.4%]), but increase in Singapore (6.3% [95% CI: 5.7%-6.9%] to 13.3% [95% CI: 10.9%-15.6%]). Men continue to bear the majority of SMuRF-less AMI prevalence, with the most rapid rise in young adults in Singapore (8.1%; 95% CI: 7.5%-8.7%) and middle-aged adults in the United Kingdom (2.3%; 95% CI: 1.5%-3.1%). The increase in SMuRF-less AMI prevalence is set to be more rapid in the overweight/obesity population (3.9%; 95% CI: 3.3%-4.5%). CONCLUSIONS: By 2040, SMuRF-less AMI will expand to a larger proportion of the AMI census in Western and Eastern populations. SMuRF-less AMI vulnerability will shift toward a younger, male-dominant demographic, with overweight/obesity as a dominant risk factor.