Role of triglyceride-glucose index in metabolic assessment of sarcoidosis patients

: Sarcoidosis is a rare granulomatous disease that can affect any organ. It leads to an increased risk of metabolic syndrome and insulin resistance, due to biochemical pathways involved in low-grade inflammation in both diseases. The aim of our retrospective case-control study was to evaluate the utility of triglyceride-glucose (TyG) index, a surrogate of insulin resistance, for metabolic assessment of sarcoidosis patients. A cohort of 90 sarcoidosis patients and a cohort of 90 control subjects were enrolled. Clinical, anamnestic, and biochemical data were collected. Results showed that TyG index values were higher in the sarcoidosis cohort than in the control group (p < 0.001), even after excluding the influence of diabetes and metabolic syndrome (p = 0.018). In the sarcoidosis cohort, TyG index was not correlated with clinical phenotyping (p = 0.358), gender (p = 0.139), radiological stage (p = 0.656), glucocorticoids cumulative dose (p = 0.682) or treatment regimen (p = 0.093), while significant positive correlations with waist circumference (p < 0.001), systolic and diastolic pressure (p = 0.041 and p = 0.029, respectively), Framingham score (p = 0.007) were found. Receiving operating characteristics curve analysis identified a TyG index optimal cut-off value of 8.64 (66.7% sensitivity, 77.8% specificity, area under the curve -AUC- 75%, 95% confidence interval -CI- 65-85, p < 0.001) to detect metabolic syndrome and a cut-off value of 8.69 (64.1% sensitivity, 70.6% specificity; AUC 67%, 95% CI 55-78, p = 0.007) to detect an intermediate cardiovascular risk according to Framingham risk score. Concluding, TyG index can be considered a useful tool for the metabolic assessment of sarcoidosis patients, given its capacity to predict metabolic syndrome and cardiovascular risk.