1670-P: Fast and Robust Assessment of Abdominal Obesity in Individuals with a Range of Cardiometabolic and Liver Tissue Characteristics—A Retrospective Analysis of UK Biobank Data

Current guidelines recommend screening individuals with diabetes for risk of metabolic dysfunction-associated steatotic liver disease (MASLD), and use of magnetic resonance imaging (MRI) in the assessment of MASLD. We compared two methods of MRI-based assessment of visceral and subcutaneous adipose tissue (VAT, SAT) and their relationship to cardiometabolic risk factors and liver tissue characteristics. A subset of 266 participants from the UK Biobank were selected based on type 2 diabetes (T2D) with imaging and controls matched for age, sex, and BMI (50% T2D, median: BMI 29kg/m2, age 56 years, 68% male). Liver MRI scans were analysed using LiverMultiScan.  A single slice at the third lumbar (L3) vertebra was extracted from whole-body Dixon MRI and cross-sectional areas of SAT and VAT were manually segmented. These were paired with SAT and VAT from a volumetric approach (top of T9 to top of femoral head). The results show a very strong correlation between a single-slice L3 assessment and volumetric assessment of body composition (VAT T2D [rho=0.9] and non-T2D [rho: 0.93]; SAT T2D [rho=0.91] and non-T2D [rho=0.94], all p values < 0.0001). Strength of correlations was maintained even with abnormal liver characteristics (MASLD in 55% and steatohepatitis in 9%) and regardless of sex, age or BMI categories (median rho value 0.92, all p values < 0.0001). The single-slice L3 method for quantifying VAT and SAT demonstrates a robust correlation with the fully-sampled volumetric assessment in individuals with a broad range of cardiometabolic characteristics. The short scanning duration (<15 min when combined with LiverMultiScan) offers a practical and efficient option for clinical applications, including monitoring treatment responses in MASLD and obesity clinical trials.