Cardiometabolic Index and chronic obstructive pulmonary disease: A population-based cross-sectional study

Background: Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide and constitutes a global health problem. The cardiometabolic index (CMI) is a new metric that combines abdominal obesity and lipid levels. Studies have shown that the prevalence of lipid metabolism disorders is greater among COPD patients and that the CMI can help reveal the potential role of lipid metabolism in disease progression by assessing the body's metabolic status; however, the association between the CMI and COPD is not known. Objective: To explore the association between the CMI and the prevalence of COPD. Methods: A cross-sectional study was conducted with 14,340 participants aged >= 20 years from the 2007-2018 NHANES databases. To assess the relationship between the CMI and the odds of COPD prevalence, we performed multivariate logistic regression analyses, subgroup analysis interaction tests, smoothed curve fitting, and threshold effect analyses. Results: The study included a total of 14,340 participants, 48.49 % male and 51.51 % female, and the average age was 49.75 +/- 17.49 years. According to the regression model adjusted for all confounding variables, participants in the highest quartile of the CMI had 22 % greater odds of having COPD than did those in the lowest quartile (OR = 1.22, 95 % CI: 1.03, 1.21, p = 0.010). A nonlinear association was found between the CMI and COPD, with an inflection point of 0.26. The OR (95 % CI) before the inflection point was 1.27 (1.12, 1.44), p = 0.0002. The interaction was statistically significant only in the sex analysis. Conclusions: The level of the CMI and the odds of COPD prevalence were positively correlated in our study. These findings suggest that managing abdominal obesity and lipid levels may help prevent or mitigate COPD, emphasizing the potential value of the CMI as an indicator for early intervention and precision therapy.