Comparison of the triglyceride/high-density lipoprotein ratio, lipid profile, and glycated hemoglobin and their association with coronary artery disease in the older adult Saudi population: a case-control study

Background and objective There is a lack of information regarding ethnic variability in the association between the triglyceride/high-density lipoprotein (TG/HDL) ratio and coronary artery disease (CAD), particularly in the Saudi population. This study aimed to evaluate the association, sensitivity, and specificity of TG/HDL ratio in relation to CAD in the Saudi population. Methods This study is a retrospective, analytical case–control study. Data were obtained from patients' electronic medical records at King Saud University Medical City (KSUMC) between 2015 and 2023. The vessel scores and Gensini score were used to assess the extent of vessel involvement and the severity of coronary occlusion. Participants were divided into two groups: (1) a healthy control group with no CAD and aged over 50 years, and (2) patients with CAD aged over 50 years. Patients with CAD underwent selective coronary angiography according to the hospital's routine procedures. Biochemical markers were measured at the time of coronary angiography. Results Multivariable logistic regression model showed that TG/HDL ratio was significantly associated with CAD (OR = 1.87, 95% CI [1.35, 2.58], p < 0.001). HbA1c demonstrated the strongest predictive ability, yielding an excellent area under the ROC curve (AUC = 0.837, 95% CI [0.807, 0.866], p < 0.001). High-density lipoprotein (HDL) levels also showed good discriminative performance (AUC = 0.716, 95% CI [0.682, 0.750], p < .001). The TG/HDL ratio demonstrated modest but statistically significant predictive ability (AUC = 0.630, 95% CI [0.592, 0.667], p < 0.001), whereas serum triglycerides (TG) levels alone showed poor-to-fair discrimination (AUC = 0.556, 95% CI [0.516, 0.596], p = 0.006). Regarding sensitivity/specificity values, the best cut-off value for the TG/HDL ratio was 1.41, sensitivity of 59% and specificity of 64%. Conclusion The TG/HDL ratio was significantly associated with the occurrence of CAD in Saudi population aged over 50 years. However, it was less sensitive and specific than HDL and HbA1c as biomarkers for detecting CAD. Overall, these findings indicate that HbA1c is the most powerful biomarker for predicting CAD among adults aged ≥ 50 years.