Newly proposed insulin resistance indexes called TyG-NC and TyG-NHtR show efficacy in diagnosing the metabolic syndrome

Purpose Obesity and insulin resistance are considered cardinal to the pathophysiology of metabolic syndrome. Several simple indexes of insulin resistance calculated from biochemical or anthropometric variables have been proposed. The study aimed to assess the diagnostic accuracy of indirect insulin resistance indicators in detecting metabolic syndrome in non-diabetic patients, including TG/HDLc, METS-IR, TyG, TyG-BMI, TyG-WC, TyG-WHtR, and new indicators TyG-NC (TyG-neck circumference) and TyG-NHtR (Tyg-neck circumference to height ratio). Methods The diagnostic accuracy of eight insulin resistance indexes was assessed using the receiver operating characteristic curves (ROC curves) in 665 adult non-diabetic patients. Then, the analysis was performed after the division into groups with proper body mass index, overweight and obese. Results All indexes achieved significant diagnostic accuracy, with the highest AUC (area under the curve) for TyG (0.888) and Tg/HDLc (0.874). The highest diagnostic performance in group with the proper body mass index was shown for TyG (0.909) and TyG-BMI (0.879). The highest accuracy in the group of overweight individuals was presented by TyG (0.884) and TG/HDLc (0.855). TG/HDLc and TyG showed the highest AUC (0.880 and 0.877, respectively) in the group with obesity. Both TyG-NC and TyG-NHtR reached significant areas under the curve, which makes them useful diagnostic tests in metabolic syndrome. Conclusions Indirect indices of insulin resistance, including proposed TyG-NC and TyG-NHtR, show an essential diagnostic value in diagnosing metabolic syndrome. TyG and TG/HDLc seem to be the most useful in the Caucasian population.