Relationship of regional adiposity to insulin resistance in nonobese Japanese type 2 diabetic patients.

Abstract

Type 2 diabetes is a heterogeneous disorder characterized by insulin resistance and/or defective insulin secretion (1,2). The mechanisms underlying insulin resistance in type 2 diabetes are not fully understood, but the numerous studies in nondiabetic populations have addressed the importance of upper body fat distribution. A study by Vague (3) was the first to show that upper body fat distribution has particularly adverse metabolic abnormalities. Higher concentrations of plasma glucose, insulin, and triglycerides have been shown to be associated with increasing abdominal body fat in nondiabetic subjects (4567). However, in diabetic patients, very little has been reported on the associations between insulin resistance and body fat distribution. Banerji et al. (8) recently disclosed that visceral but not subcutaneous abdominal fat volume is associated with insulin resistance in black subjects with type 2 diabetes. In contrast, Abate et al. (9) recently demonstrated that subcutaneous but not intraperitoneal nor retroperitoneal fat volume is associated with insulin resistance in non-Hispanic whites with type 2 diabetes. The reason for the discrepant result between the two groups is unknown, but it can be speculated that there may be an ethnic difference in the relationship between insulin resistance and body fat distribution in type 2 diabetes. Nonobese Japanese type 2 diabetic patients are unique in that they are divided into two variants: those with insulin resistance and those with normal insulin sensitivity (101112). However, to the best of our knowledge, the relationship between insulin resistance and body fat distribution has not been investigated in nonobese Japanese type 2 diabetic populations. Thus, the aim of the present study was to investigate the relationships among insulin resistance and subcutaneous or visceral fat area in nonobese Japanese type 2 diabetic patients. A total of 75 nonobese Japanese type 2 diabetic patients at …