Association between cardiometabolic index and hypertension among US adults from NHANES 1999–2020

Hypertension, a major global health issue and leading cause of death, is often under-assessed by traditional metrics like Body Mass Index which fail to capture comprehensive cardiovascular risks associated with obesity. The Cardiometabolic Index (CMI), which evaluates abdominal obesity and dyslipidemia, offers a more accurate assessment of visceral fat and metabolic dysfunction. In this study, we analyzed data from 45,250 participants from the National Health and Nutrition Examination Survey spanning 1999 to 2020. Using multivariable logistic regression, we explored the association between CMI and hypertension, employing Restricted Cubic Spline analysis to assess non-linear relationships and two-piecewise linear regression to identify threshold effects. Subgroup analyses confirmed the consistency of our findings across various demographic and clinical characteristics. Findings confirmed that hypertensive participants exhibited significantly higher CMI levels (median 0.46 vs. 0.73), with adjusted logistic regression showing a notable association between increased CMI and hypertension prevalence (OR 1.30, 95% CI 1.25-1.35, P < 0.01), characterized by a nonlinear L-shaped curve with a critical threshold identified at a CMI value of 1.37. Subgroup analysis revealed a more pronounced impact of CMI on hypertension in females. These results underscore CMI's potential to enhance cardiovascular risk assessment across diverse U.S. populations.