Transient Elastography Measures of Hepatic Steatosis and Fibrosis Are Associated With Body Composition Among US Adolescents

Regional fat distribution and hepatic fibrosis and steatosis severity in patients with nonalcoholic fatty liver disease and type 2 diabetes

Background

Epidemiologic findings suggest that measures of body fat distribution predict health outcomes independent of the overall body fat assessed by body mass index (BMI). This study aimed to evaluate the associations of overall and regional body fat with the severity of hepatic steatosis and fibrosis in type 2 diabetic patients with non-alcoholic fatty liver disease.

Methods

Bioelectric impedance analysis and two newly developed anthropometric indices, namely, A Body Shape Index (ABSI) and Body Roundness Index (BRI), were used to estimate the body fat. Based on fibroscan parameters, significant hepatic fibrosis and severe steatosis were defined as ≥F2 and >66%, respectively.

Results

Higher total body fat (odds ratio [OR] 1.107, 95% confidence intervals (CI) 1.038-1.182, p = 0.002), trunk fat (OR 1.136, 95% CI 1.034-1.248, p = 0.008) and leg fat (OR 1.381, 95% CI 1.139-1.674, p = 0.001) were associated with liver fibrosis. However, in contrast to the total body fat (OR 1.088, 95% CI 1.017-1.164, p = 0.014) and leg fat (OR 1.317, 95% CI 1.066-1.628, p = 0.011), the trunk fat was not associated with severe hepatic steatosis. BRI performed better than trunk, leg and total body fat in predicting hepatic steatosis (OR 2.186, 95% CI 1.370-3.487, p = 0.001) and fibrosis (OR 2.132, 95% CI 1.419-3.204, p < 0.001). Moreover, the trunk to leg fat ratio and ABSI were not independent predictors of either steatosis or fibrosis (p > 0.05).

Conclusion

BRI revealed a superior predictive ability for identifying the degree of hepatic steatosis and stiffness than other obesity indices. Additionally, higher levels of adiposity in the trunk, legs, and overall body were linked to an increased risk of developing liver fibrosis. Although trunk fat did not show an association with severe hepatic steatosis, an increase in leg and total fat was related to liver steatosis.

Obesity and Body Composition in Relation to Liver and Kidney Ultrasound Elastography in Paediatric Patients with Either Hypertension or Chronic Kidney Disease

(1) Background: Ultrasound elastography is a novel ultrasound technique for evaluating tissue elasticity. One of the key factors influencing the measurement in children is excess weight. This study aimed to evaluate the effect of body composition, namely, fat mass, on liver and kidney ultrasound elastography in paediatric patients. (2) Methods: 114 participants, in whom bioimpedance, along with liver and kidney ultrasound elastography, were performed, were included (37 patients with chronic kidney disease, 46 patients with hypertension, and 31 healthy subjects). (3) Results: Bioimpedance analysis showed a significant correlation between liver elastography parameters and the phase angle (p = 0.002), fat-free mass (p = 0.001), body cell mass (p = 0.001), total body water (p = 0.001), extracellular water (p = 0.006), and, to lesser extent, fat mass (p = 0.041). On the contrary, kidney elastography parameters strongly correlated only with fat mass (p < 0.001 for both kidneys). (4) Conclusions: Liver and kidney stiffness increased in overweight participants and showed significant correlation with fat mass, particularly in the case of kidney elastography.