Anthropometric Indices and Metabolic Dysfunction-Associated Fatty Liver Disease in Males and Females Living With Severe Obesity.

Introduction: Metabolic dysfunction-associated fatty liver disease (MAFLD) is highly prevalent among people living with severe obesity (body mass index [BMI] ≥ 35 kg/m²). However, it remains unknown how sex and adipose tissue distribution are related to MAFLD onset and progression into metabolic dysfunction-associated steatohepatitis (MASH) or advanced stages of fibrosis. Methodology: We retrospectively studied patients with severe obesity who were eligible for bariatric surgery. Demographic characteristics, biomarkers, and cardiometabolic comorbidities were reported. Anthropometric indices such as BMI, waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), neck circumference (NC), lipid accumulation product (LAP), visceral adiposity index (VAI), body adiposity index (BAI), abdominal volume index (AVI), and body roundness index (BRI) were measured or calculated. MAFLD, MASH, and stages of fibrosis (F1-F4) were established from perioperative liver biopsies. Standardized univariate and multivariate logistic regression analyses were used to examine the association between demographic variables, anthropometric indices, cardiometabolic conditions, and the risk of MASH or severe fibrosis (F2-F4). Results: A total of 2091 participants with severe obesity were included in the analyses; BMI 47.9 ± 7.3 kg/m², age 46.2 ± 11.2 years, and 68.4% females. Overall, MAFLD prevalence was 79.5%, with 44.5% having MASH and 24.4% having severe fibrosis (Stage 2 or higher). No anthropometric indices of adiposity were associated with MASH or fibrosis severity. In this population, female sex was a risk factor for severe fibrosis (OR: 1.27, 95% CI 1.01-1.59, p < 0.05). Conclusions: MAFLD and MASH are highly prevalent in individuals living with severe obesity, but no anthropometric indices or laboratory tests are good predictors of MAFLD or MASH in this population. When MAFLD is diagnosed, our results suggest that females with severe obesity might be at higher risk of advanced stages of fibrosis.