The Clínica Universidad de Navarra-Body Adiposity Estimator index is a reliable tool for screening metabolic dysfunction-associated steatotic liver disease: an analysis from a gender perspective

Abstract Background The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) Index, serves as an effective tool for evaluating body fat (BF) levels. This research seeks to clarify the association between the CUN-BAE Index and metabolic dysfunction-associated steatotic liver disease (MASLD) from a gender perspective. Methods The study utilized data from a comprehensive health assessment initiative known as “Human Dock”, involving 14,251 participants. MASLD was diagnosed using abdominal ultrasound, primarily evaluated based on the following sonographic features: hepatorenal echo contrast, vascular blurring, deep attenuation, liver brightness. First, we evaluated the association of MASLD with the CUN-BAE Index using multivariate logistic regression. Second, we visualized this association and estimated potential threshold effect points using the restricted cubic spline (RCS) regression model. Ultimately, we evaluated the ability of the CUN-BAE Index to detect MASLD through receiver operating characteristic (ROC) curves. Results The female-to-male ratio was 1:1.08, with a MASLD prevalence rate of 17.59%. Following the adjustment for confounding variables, an increase of one unit in the CUN-BAE Index corresponded to a 14% increase in the risk of MASLD for males and an 18% increase for females. RCS analysis revealed an S-shaped relationship between MASLD prevalence and the CUN-BAE Index for both genders, with potential threshold effect points at approximately 30 in females and 15 in males. Beyond these threshold points, the prevalence of MASLD increased rapidly. Further subgroup analyses indicated significant differences in the relationship of the CUN-BAE Index with MASLD within age and body mass index (BMI) subgroups in females, with a stronger association observed in younger and non-obese female participants. Additionally, ROC analysis revealed that the CUN-BAE Index possesses a strong ability to distinguish MASLD in both genders, especially in females. Conclusions This research is the first to identify a positive relationship between the CUN-BAE Index and MASLD. The CUN-BAE Index appears to be more suitable for early screening of MASLD in females.