MRI-based examinations of hepatic steatosis and body fat are becoming more familiar and useful for metabolic studies including NAFLD. MRI-estimated proton density fat fraction (MRI-PDFF) can haptic fat exactly without biopsy, enabling us to evaluate the effect of liver fat more sophisticatedly than ever. Although hepatic fat and visceral fats are both important for metabolic and cardiovascular diseases, detailed evaluation of the effect of each fat depot on various metabolic profiles have not been performed, In the present study, we evaluated the differential effect between hepatic and visceral fats on various metabolic profiles including glucose and lipid metabolism, islet cell function, insulin resistance, and inflammation. A total of 82 subjects (25 healthy volunteers and 57 patients with suspected, or proven NAFLD) who underwent MRI examinations for MRI-PDFF and visceral fat measurement. Additionally, anthropometric and laboratory studies and total body fat measurement by DXA were also performed. Other causes of chronic liver diseases, such as alcoholic, autoimmune or viral hepatitis, and other diseases, were excluded from the study. The amounts of hepatic fat and visceral fats measured by MRI showed similar significant correlations with HOMA-IR (r=0.540 vs. r=0.538, p <0.01, respectively) as with A1C (r=0.448 vs. r=0.495, p <0.01 each). However, hepatic fat showed more close association with FBS, triacylglycerol, complement factor C3, and cytokeratin 18. Visceral fat correlated more with fasting plasma insulin, glucagon and angiotensinogen levels. Total body fat measured by DXA did not show such characteristic patterns of correlations and showed only a weak or no correlation with those parameters. Thus, our results showed that both hepatic fat and visceral fat depots are important determinants of whole-body insulin resistance and glucose metabolism.

Disclosure

I. Park: None. K. Lee: None. D. Lee: None.

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