Correlation between the triglyceride-glucose index and maximal oxygen uptake in coronary artery disease

Abstract Introduction The triglyceride–glucose (TyG) index has emerged as a reliable marker of metabolic syndrome and shows predictive value for cardiovascular events. Maximal oxygen uptake (VO2 max) represents the gold-standard measure of cardiopulmonary fitness and is strongly associated with prognosis and overall cardiovascular mortality. The aim of this study was to assess the relationship between the TyG index and VO2 max in patients with coronary disease. Methods Consecutive patients presenting for an initial post–myocardial infarction follow-up were included in this observational cross-sectional study. Baseline data, cardiovascular risk factors, laboratory tests (glucose (mg/dL) and triglycerides (mg/dL)) from a fasting blood sample were collected. TyG index was calculated with the previously described and validated formula: TyG index = ln triglycerides (mg/dL) × plasma glucose (mg/dL)/2. Cardiopulmonary exercise testing was performed to assess VO2 max. Linear regression models and Pearson test correlation were used to investigate the correlation between TyG index and VO2 max. A two-tailed p0.05 was considered significant. Results A total of 107 participants were included, 21 (19,6%) were females, median age was 57 ± 10,9 years, 68 (63,6%) were diagnosed with STEMI and 39 (36,4%) with NSTEMI, 80 (74,8%) had arterial hypertension, 9 (8,4%) had type 2 diabetes, 68 (63,6%) had hyperlipidaemia. 49 (45,8%) had a history of smoking and 41 (38,3%) had a positive family history of cardiovascular disease. The TyG index demonstrated a significant inverse association with VO2 max (r = –0.287, p = 0.004), with higher TyG values correlating with lower cardiopulmonary fitness (Figure 1). In the univariate linear regression model, the TyG index independently predicted VO2 max (B = –3.35, 95% CI –5.60 to –1.10, p = 0.004), explaining 8.3% of its variance. In the multivariate model, the TyG index remained independently inversely associated with VO2 max after adjustment for sex, age and traditional risk factors (Table 1). Conclusion Our findings demonstrate a significant inverse association between the TyG index and VO2 max, suggesting that higher metabolic risk is linked to reduced cardiorespiratory fitness. These results highlight the potential utility of the TyG index as a simple, accessible marker for early identification of patients with impaired exercise capacity, supporting its integration into cardiovascular risk stratification and rehabilitation planning.For image description, please refer to the figure legend and surrounding text. For image description, please refer to the figure legend and surrounding text.