Association between the triglyceride glucose-body mass index and mortality risk in cardiovascular disease populations: a longitudinal cohort study

Abstract

Background: Cardiovascular disease (CVD) is a leading cause of global mortality, with increasing prevalence and impact, especially in the elderly and developing countries. Insulin resistance (IR) plays a significant role in CVD progression, and the triglyceride glucose-body mass index (TyG-BMI) index, combining fasting glucose and triglycerides, offers a simple, cost-effective method for assessing IR. However, its prognostic value in CVD populations remains underexplored. This study aims to investigate the relationship between TyG-BMI and mortality in CVD patients. Methods: Data from the National Health and Nutrition Examination Survey (NHANES) (1999–2018) combined with the linked National Death Index were analyzed. The CVD population was split into two groups (Q1 and Q2) based on the median TyG-BMI. The primary outcomes were all-cause mortality and cause-specific mortality. Results: The study ultimately included 2,576 participants, of which 56% were male. The median age of the participants was 69 years, and the median TyG-BMI was 256.59. After adjusting for potential confounders, a negative relationship was found between TyG-BMI and all-cause mortality in populations with CVD, coronary heart disease (CHD), congestive heart failure (CHF), and heart attack. The hazard ratios (HR) and 95% confidence intervals (CI) were 0.73 (0.64, 0.85), 0.67 (0.53, 0.84), 0.69 (0.54, 0.88), and 0.73 (0.59, 0.91), respectively. At the same time, a notable inverse relationship was noted between the TyG-BMI and non-CVD mortality in the CVD and CHD population, with HR and 95% CI of 0.70 (0.58, 0.84) and 0.61 (0.45, 0.82), respectively. In this study, there was no observed noteworthy relationship between TyG-BMI and CVD mortality. Furthermore, sensitivity analysis yielded similar results. Conclusion: Among populations with CVD in the United States, a heightened TyG-BMI was notably correlated with a decreased likelihood of mortality. This index can effectively classify the risk levels of CVD patients and may serve as a valuable prognostic marker.