Prediabetes and risk for myocardial infarction by hypertension status in a Chinese population: a prospective cohort study

Background: Whether prediabetes alone or combined with hypertension is a more important risk factor for cardiovascular disease is controversial. In this study, we aimed to examine this association to fill the research gap. Methods and results: A total of 85 570 participants (mean age: 58.0 years) without diabetes and no previous myocardial infarction (MI) were recruited for this study. Participants were divided into four groups according to prediabetes status and were further stratified according to hypertension status. Hazard ratios with 95% confidence intervals (CIs) were calculated using Cox regression models. After a mean follow-up period of 11.0 years, 1122 (rate 1.19/1000 person-years) individuals developed MI. Compared with participants without either condition, the multivariable-adjusted hazard ratios for MI events among participants with prediabetes alone, hypertension alone, and both prediabetes and hypertension were 1.06 (95% CI: 0.84-1.36), 1.73 (95% CI 1.49-2.00), and 1.89 (95% CI 1.57-2.27), respectively. Among participants with and without hypertension, there was no association between prediabetes and an increased risk for MI (hazard ratio: 1.11 95% CI 0.94-1.32 and hazard ratio: 1.02 95% CI 0.80-1.30, respectively). Conclusion: The current study indicated that among the Chinese general population, the increased risk of MI associated with prediabetes is largely driven by concomitant hypertension rather than prediabetes per se.