Exploring the association between triglyceride glucose index-related obesity indices and asthma-COPD overlap: NHANES 2001 to 2018.

The association between asthma and chronic obstructive pulmonary disease overlap (ACO) and insulin resistance (IR) has not been adequately investigated. Triglyceride glucose (TyG) index-related obesity indices offer a novel measure for assessing IR. We aimed to explore the associations between these indices and ACO in US population. Data used in this study were obtained from the National Health and Nutrition Examination Survey. We performed logistic regression analysis, restricted cubic spline modeling, subgroup analysis, sensitivity analysis, and additional analyses to examine the association between TyG-related obesity indices and ACO. The study involved 11,453 participants. TyG-waist to height ratio, TyG-body mass index, TyG-weight adjusted waist index, and TyG-waist circumference were all associated with ACO in multivariate logistic regression, with adjusted odds ratios (ORs) (95% confidence interval [CI]) of 1.23 (1.11-1.37), 1.32 (1.12-1.57), 1.20 (1.08-1.34), 1.14 (1.06-1.22), respectively. The highest quartile of all indices had the strongest link with ACO, as evidenced for TyG-waist to height ratio (OR [95% CI] = 1.80 [1.29-2.52]), TyG-body mass index (OR [95% CI] = 1.59 [1.19-2.14]), TyG-weight adjusted waist index (OR [95% CI] = 1.82 [1.23-2.69]), and TyG-waist circumference (OR [95% CI] = 1.75 [1.28-2.39]) in the fully adjusted model. Most subgroup, sensitivity, and supplementary analyses revealed similar results. TyG-related obesity indices were significantly associated with ACO. This finding indicates a strong correlation between high IR and susceptibility to ACO in the US population.