Background: The purpose of this study was to investigate the association of the triglyceride glucose (TyG) index, a surrogate marker of insulin resistance (IR) with a high sensitivity of 96.5% and a specificity of 85.0% for the diagnosis of IR, with computed tomography (CT) features in patients with tuberculosis and diabetes mellitus.
Methods: A total of 247 subjects were enrolled from July, 2020 to May, 2021. The basic clinical features and CT features were analyzed. In addition, multivariate logistic regression analysis models were employed to evaluate the association of the TyG indicator with CT features in participants.
Results: In the quartile groups of TyG index, air bronchial sign detection rate was 11.7%, 14.5%, 23.2%, and 44.1%; large segmented leafy shadow detection rate was 27.9%, 40.6%, 46.4%, and 66.2%; thick-walled cavity was found in 38.2%, 43.4%, 57.9%, and 69.1%; the rate of multiple cavities was 17.6%, 27.5%, 36.2%, 52.9%; the rate of lymph node enlargement was 22.1%, 17.4%, 28.9%, and 38.2%, respectively. In addition, the positive relation with the TyG index and the prevalence of abnormal CT signs was observed in the fully adjusted model: TyG, per one-unit increase: air bronchial sign: adjusted odds ratio (AOR) 3.92, 95% CI 1– 15.35, P = 0.049; multiple cavities: AOR 4.1, 95% CI 1.26– 13.31, P = 0.019; thick-walled cavity: AOR 2.89, 95% CI 1.05– 8.03, P = 0.041. In quartile of TyG index, compared with patients in quartile 1, the AOR (95% CI) values for air bronchial sign in quartile 4 was 8.1 (1.7– 44), p = 0.011; multiple cavities was 7.1 (1.7– 32), p = 0.008; thick-walled cavity was 7.8 (1.9– 34.7), p = 0.005.
Conclusion: The present study showed that an increased TyG index was positively related to the severity of patients with T2DM-PTB.
Keywords: CT features, insulin resistance, triglyceride glucose index, pulmonary tuberculosis, T2DM