Effect of Liver Surface Nodularity, Sarcopenia and Visceral Obesity as Risk Factors in African Americans Adults
Benjamin Rushing1, Sarah Miller1, Elliot Varney1, Charlene Claudio1, Caroline Doherty1, Juliana Sitta1, Niki Patel1, Khalid Manzoul1, Rana Gordji1, Amy Krecker1, Gerri Wilson1, Stella Powell1, Seth Lirette2, Edward Florez1, Candace Howard1
1Department of Radiology, University of Mississippi Medical Center, Jackson, MS
2Department of Data Science, University of Mississippi Medical Center, Jackson, MS
This retrospective observational study was designed to assess the association between Liver Surface Nodularity, muscle mass and visceral fat depots in a high-risk population of African Americans (AAs). Non-enhanced abdominal CT images from AAs were analyzed (N=2006). Waist circumference (WC) and sagittal abdominal diameter (SAD) were measured. Muscle volumes (paraspinal, abdominal wall, psoas) and regional abdominal fat volumes, including visceral adipose tissue (VAT) and superficial adipose tissue (SAT), were quantified using a multi-layer segmentation software. Liver surface nodularity (LSN) scores were measured by two readers using a validated quantitative software. Linear regression models were used to associate LSN scores with body composition. Intraclass correlation coefficients (ICC) were used to assess inter-observer agreement. LSN scores showed direct proportionality with WC (R2=0.18, 0.42, p<0.001), SAD (R2=0.20, 0.45, p<0.001), and all fat compartments. There was no statistically supported relationship between WC, SAD and LSN when WC <100cm (ß=0.0, p=0.707) and SAD <25cm (ß=0.01, p=0.267). However, for SAD ≥25cm, each 1cm increase in SAD was associated with a 0.07 unit increase in LSN score (ß=0.07, p<0.001). WC ≥100cm also correlated with an increase in LSN (ß=0.02, p<0.001). Finally, interobserver agreement was excellent (ICC>0.89, N=300). Anthropomorphic measurements above a certain cut-off point (SAD ≥25cm; WC ≥100cm), were linked to increased LSN scores.