Inverse association between cardiometabolic index and endometriosis in women of reproductive age: A cross-sectional, population-based study

ObjectiveThis study aimed to investigate the relationship between the cardiometabolic index and the prevalence of endometriosis among reproductive-age women in the United States. This cross-sectional population-based study used data from the National Health and Nutrition Examination Survey (NHANES) 2003-2006.MethodsWe conducted a cross-sectional analysis using data from 1156 women aged 20-54 years who participated in NHANES 2003-2006. Cardiometabolic index was calculated as the product of the waist-to-height ratio and the triglyceride-to-high-density lipoprotein cholesterol ratio. Logistic regression models adjusted for demographic, reproductive, and lifestyle factors were used to assess the association between cardiometabolic index and self-reported endometriosis. Structural equation modeling was applied to explore potential mediating and moderating effects.ResultsA significant inverse association between cardiometabolic index and endometriosis was observed. In the fully adjusted model, each one-unit increment in cardiometabolic index corresponded to a 42% reduction in the odds of self-reported endometriosis (odds ratio = 0.58, 95% confidence interval = 0.38-0.91, <i>p</i> < 0.05). Compared with women in the lowest cardiometabolic index quartile, those in the highest quartile exhibited a 51% (precise value: 50.6%) lower prevalence of endometriosis (odds ratio = 0.49, 95% confidence interval = 0.29-0.83). Additionally, the use of oral contraceptives significantly moderated the cardiometabolic index-endometriosis relationship <i>p</i> for interaction <0.05.ConclusionsCardiometabolic index is significantly and inversely associated with endometriosis among US women of reproductive age. However, given the cross-sectional design of this study, these findings should be considered preliminary, and causal inferences cannot be drawn.