Associations between cardiometabolic index and sleep disorders: Results from NHANES 2015 to 2020
Sleep disorders have already been recognized as a public health concern, with evidence suggesting that lipid metabolism significantly affects sleep quality and circadian rhythms. Cardiometabolic index (CMI), a novel lipid index, has been confirmed to be associated with obesity-associated metabolic disorders, such as diabetes and cardiovascular disorders. Despite these findings, the exact relationship between CMI and sleep disorders remains to be fully validated. Consequently, our objective was to investigate the association between CMI and sleep disorders using data from the National Health and Nutrition Examination Survey (NHANES). Based on data from NHANES spanning 2015 to 2020, this study employed weighted multivariate logistic regression and restricted cubic spline (RCS) regression analysis to investigate the relationship between CMI and sleep disorders. Additionally, receiver operating characteristic analysis and the area under the curve were also utilized to assess the predictive performance of CMI for sleep disorders. Subgroup analyses and interaction tests were conducted to examine the consistency of this association across different populations. A positive association between CMI and sleep disorders was found in a cohort comprising 5817 participants aged 20 and above, which was further verified to be nonlinear through RCS regression analysis. Within the context of a fully adjusted model, when CMI was considered as a continuous variable, each one-unit increase was linked to a 17% increase in the prevalence of sleep disorders (odds ratio [OR] = 1.17; 95% CI: 1.06–1.29; P = .004). Upon stratifying CMI into quartiles, it was observed that participants in the highest quartile exhibited an 81% greater risk of developing sleep disorders compared to those in the lowest quartile (OR = 1.81; 95% confidence interval [CI]: 1.29–2.54; P = .002). Subgroup analyses and interaction tests demonstrated that the association between CMI and sleep disorders remained consistent across different subgroups, and no significant modification of this relationship was observed by other covariates except for body mass index. An elevated CMI is correlated with a higher probability of sleep disorders among individuals in the United States. Given the difficulty in establishing a causal relationship between the 2, further extensive prospective studies are necessary to investigate the role of CMI in the development of sleep disorders.