Association Between Fasting Blood Glucose and Myocardial Infarction Risk: Findings From the 2015–2018 NHANES Database and Mendelian Randomization Studies

Introduction Fasting blood glucose and myocardial infarction share some common pathophysiological risk factors, but the exact relationship between them remains unclear. This study aims to provide evidence for the association between fasting blood glucose and myocardial infarction by analyzing data from the National Health and Nutrition Examination Survey (NHANES) 2015–2018 and Mendelian randomization (MR) analysis. Methods A two‐sample MR study was conducted to explore the causal relationship between fasting blood glucose and myocardial infarction using summary statistics from genome‐wide association studies (GWAS). The inverse variance weighted (IVW) method and other supplementary MR methods were mainly used to verify the causal association, and sensitivity analysis was performed to confirm the robustness of the results. In addition, weighted multivariable adjusted logistic regression analysis was used to evaluate the relationship between fasting blood glucose and the myocardial infarction–related multivariable association model constructed with HDL as the core indicator based on NHANES data from 2015 to 2018. Results A total of 4807 participants were included in the observational study based on NHANES data. Weighted multivariable adjusted logistic regression analysis showed a positive correlation between fasting blood glucose and the myocardial infarction model, with an odds ratio (OR) of −0.027 and a 95% confidence interval (CI) of [−0.042, −0.011]. MR analysis also indicated a causal relationship between myocardial infarction and fasting blood glucose (IVW: OR = 1.0026, 95% CI = 1.0006–1.0046, p = 0.0098). Sensitivity analysis further confirmed the robustness and reliability of these study results (all p > 0.05). Conclusion There is a causal relationship between fasting blood glucose and myocardial infarction.