A higher triglyceride-glucose index was independently associated with severe coronary artery disease in patients with non–ST-segment elevation myocardial infarction, according to a dual-center analysis from China.
The study included 596 patients admitted to Shenzhen Nanshan People’s Hospital and The First Affiliated Hospital of Jinan University between September 2019 and May 2022. All had a first non-ST-segment elevation myocardial infarction (NSTEMI) diagnosis and underwent coronary angiography within 24 hours. Exclusions included prior bypass surgery, takotsubo cardiomyopathy, myocarditis, cardiomyopathy, pulmonary embolism, poor angiographic quality, or incomplete data.
Severe coronary artery disease (CAD), defined as left main stenosis of at least 50% or three-vessel stenosis of at least 50% with a SYNTAX score greater than 22, was identified in 17% of patients. The triglyceride-glucose (TyG) index, calculated from fasting glucose and triglyceride values, predicted severe left main and three-vessel disease. Each unit increase in TyG was associated with greater odds of severe disease. The optimal cut point was 7.39, above which patients had higher SYNTAX scores, more comorbidities, and less favorable laboratory profiles. Patients above the threshold were more likely to have obesity, hypertension, diabetes, hyperlipidemia, and chronic kidney disease, along with higher glucose, triglycerides, hemoglobin A1c, troponin I, and NT-proBNP, and lower HDL cholesterol.
When tested as a diagnostic model, TyG modestly improved prediction. Age alone yielded an area under the curve (AUC) of 0.726. Adding TyG and ST-segment elevation in lead aVR increased the AUC to 0.759. Subgroup analyses showed consistent associations across patients with or without diabetes, hypertension, hyperlipidemia, or varying hemoglobin A1c levels. A dose–response relationship was observed.
“The precise mechanisms responsible for the correlation between TyG and CAD have not been definitively explained,” said lead study author Xueying Han, MD, of Shenzhen Nanshan People’s Hospital. “First, TyG exhibits a robust correlation with the gold standard technique for assessing IR [insulin resistance], establishing itself as a simple and reliable marker of IR.”
Limitations included the retrospective cross-sectional design, modest sample size, recruitment from only two hospitals, and incomplete medication histories, which could have influenced TyG levels and outcomes. Larger prospective studies are needed to validate these findings and assess clinical applications.
The study was supported by local institutional grants. The researchers declared no competing interests.
Source: BMJ Open
