Investigating the Causal Impact of COVID-19 on Acute Myocardial Infarction: A Multi-ancestry Mendelian Randomization Study

Observational studies suggest an association between COVID-19 and acute myocardial infarction (AMI), however, whether this relationship is causal remains unclear. We conducted a multi-ancestry Mendelian randomization (MR) study across European, East Asian, South Asian, and African populations, evaluating three COVID-19 phenotypes: very severe COVID-19, hospitalized COVID-19, and general infection association with AMI. GWAS summary statistics were obtained from the COVID-19 Host Genetics Initiative Round 7 and UK Biobank/Biobank Japan for AMI. Inverse-variance weighted (IVW) MR was the primary method, with fixed- or random-effects models selected according to heterogeneity test. MR-Egger, weighted median and weighted mode were conducted as sensitivity analyses. In European ancestry, genetic liability to very severe COVID-19 and hospitalized COVID-19 was slightly inversely associated with AMI risk, but without statistical significances across sensitivity analyses. Hospitalized COVID-19 showed a suggestive but non-significant inverse association in South Asian ancestry. No significant associations were identified in East Asian or African ancestries. Our findings did not support a robust causal association between COVID-19 susceptibility or severity and AMI risk across ancestries, suggesting that the observed cardiovascular burden may be driven more by acute pathophysiological mechanisms than shared genetic architecture.