Ultrasound assessment of abdominal fat: Subcutaneous maximum thickness as a practical marker of metabolic risk in primary care

Ultrasound is a cost-effective tool for characterizing abdominal fat, with measurement accuracy comparable to advanced imaging techniques. A lack of standard operating procedures has hindered widespread adoption. Our study aimed to describe, through ultrasound, the adipose tissue layers of the abdominal wall in patients living with excess body fat. Cross-sectional study including 103 adults. Patients with normal fat mass were excluded. Fat mass was quantified through Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE). Ultrasound was performed at the midpoint between the xiphoid appendix and the navel (1–3 cm above the umbilicus) along the alba line. Mean age (SD) was 46.6 (14.4) years, and 74.8% were women. A subcutaneous adipose tissue (SAT) measurement >1.8 cm showed significantly higher adiposity indices (BMI, CUN-BAE), systolic blood pressure, and laboratory metabolic parameters (insulin, HOMA-IR, triglycerides, creatinine) than those with SAT ≤1.8 cm. SAT was associated with an increased prevalence of dysglycemia (Q4 vs. Q1, adjusted OR 6.13; 95% CI 1.38–27.28), showing strong discriminative ability (AUC = 0.79; 95% CI 0.69–0.89). In a primary care setting, ultrasound characterization of abdominal fat should include measurement of the SAT maximum layer above the navel along the alba line, as it may aid in evaluating metabolic risk. • Adipose tissue ultrasound is an accurate tool to assess people living with obesity. • Maximum SAT (1–3 cm above the navel) >1.8 cm is linked to metabolic derangements. • Maximum SAT was associated with higher dysglycemia risk in adjusted models. • In primary care, abdominal adipose tissue ultrasound helps assess metabolic risk.