Liver fat is increased in type 2 diabetic patients and underestimated by serum alanine aminotransferase compared with equally obese nondiabetic subjects.

Description

In this cross-sectional study of middle-aged individuals, Kotronen et al. compared liver fat content, intra-abdominal (visceral) fat and other indices of body composition, as well as insulin sensitivity and liver enzymes markers in patients with type 2 diabetes and in healthy sex and age-matched controls with comparable body mass index (BMI). In both groups, liver fat (measured by 1H-magnetic resonance spectroscopy) was positively associated with BMI, waist circumference, fasting insulin, triglycerides, the liver enzymes S-AST and S-ALT, and negatively with HDL cholesterol levels. Importantly, the authors found that, compared to healthy sex and age-matched individuals, patients with type 2 diabetes had an 80% difference in liver fat despite having only 16% more intra-abdominal fat accumulation. Moreover, the authors noticed that S-ALT clearly underestimated liver fat accumulation in patients with type 2 diabetes. These results concur with several other recent publications by this group and others on the importance of liver fat as an underdiagnosed phenotype in patients with the metabolic syndrome and associated co-morbidities such as type 2 diabetes.