Implications of Abdominal Adipose Tissue Distribution on Nonalcoholic Fatty Liver Disease and Metabolic Syndrome: A Chinese General Population Study

Abstract

INTRODUCTION: Visceral adipose tissue (VAT) has been found to play a critical role in the development of metabolic syndrome and nonalcoholic fatty liver disease (NAFLD) independent of generalized obesity. METHODS: In this secondary study of prospectively acquired data, 625 participants underwent magnetic resonance spectroscopy and chemical shift fat–water separation MRI (2-point Dixon) of the liver and whole abdomen, respectively, in a 3 Tesla magnet. Whole abdominal VAT and subcutaneous adipose tissue (SAT) were extracted from the 2-point Dixon image series using an automated method. Clinical/anthropometric/blood biochemistry parameters were measured. Using region-specific body mass index, participants were classified into 3 paired subgroups (lean, overweight, and obese) and presence of NAFLD (liver fat content ≥ 5.5%). RESULTS: All relevant clinical/anthropometric/blood biochemistry characteristics and liver enzymes were statistically significant between groups (P < 0.001). NAFLD was found in 12.1%, 43.8%, and 68.3% and metabolic syndrome in 51.1%, 61.9%, and 65% of the lean, overweight, and obese, respectively. Odds ratio for metabolic syndrome and NAFLD was increased by 2.73 (95% confidence interval [CI] 2.18–3.40) and 2.53 (95% CI 2.04–3.12), respectively, for 1SD increase in VAT volume while prevalence of metabolic syndrome was increased by 2.26 (95% CI 1.83–2.79) for 1SD increase in liver fat content (%). VAT/SAT ratio in the lean with fatty liver showed the highest ratio (0.54) among all the subgroups, without a significant difference between the lean and obese with NAFLD (P = 0.127). DISCUSSION: Increased VAT volume/disproportional distribution of VAT/SAT may be vital drivers to the development of metabolic syndrome and NAFLD irrespective of body mass index category.

The Interplay between Insulin Resistance, Inflammation, Oxidative Stress, Base Excision Repair and Metabolic Syndrome in Nonalcoholic Fatty Liver Disease

“…In general, lipodystrophy, obesity, NAFLD, and MS demonstrate disturbances in visceral fat tissue, which together with subcutaneous tissue, form white adipose tissue [188]. Often, the visceral adipose tissue/subcutaneous adipose tissue ratio is increased in NAFLD [189]. Excessive production of FFAs by visceral fat tissue in a pathological situation impairs the PI3K/Akt signaling pathway, increases oxidative stress, and reduces insulin sensitivity [5].…”

The Association of Pericardial Fat and Peri-Aortic Fat With Severity of Nonalcoholic Fatty Liver Disease

“…Independent positive association were observed between VAT and NAFLD [21]. And the reverser association between subcutaneous adipose tissue (SAT)and NAFLD has also been reported [22]. It is probably due to retaining adipose tissue in subcutaneous in human obesity could reduce overall and regional-speci c VAT and improve insulin resistance [23].…”

The Perirenal Fat Thickness Was Associated with Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus

“… 20 Chiyanika C suggested that VAT may be a vital driver of NAFLD based on a prospectively acquired data. 16 Another large cohort study indicated that VAT was longitudinally associated with higher risk of incident NAFLD. 15 In terms of severity of NAFLD, we did not get positive result about PrFT, PnFT and NAFLD.…”

“… 12–16 The obesity indices in clinical studies included BMI, 12 , 13 waist circumference 14 and visceral obesity. 15 , 16 However, not all obese patients develop NAFLD and, more importantly, NAFLD can occur in nonobese and even lean individuals, especially in Asian populations. Previous study indicated that 40% of global NAFLD patients were non-obese and approximately 20% were lean.…”

“… 20 Chiyanika C conducted one study using prospectively acquired data and suggested that increased visceral adipose tissue (VAT) may be a vital driver to the development of NAFLD irrespective of BMI category. 16 In addition, there is an established relationship between visceral fat and liver steatosis. 21 In a large cohort study, larger areas of VAT were associated with higher risk of incident NAFLD.…”