Heterogeneous glycaemic and insulinaemic responses to oral glucose in non-diabetic men: interactions between duration of obesity, body fat distribution and family history of diabetes mellitus.

The interaction between environmental and genetic factors in the alterations of glucose-insulin homeostasis was studied in 104 non-diabetic men. Family history of diabetes mellitus was used as an index of genetic predisposition to diabetes. Body composition was measured by underwater weighing whereas subcutaneous and visceral adipose tissue areas were measured at the abdominal and femoral levels by computed tomography. The sample was first divided into two groups. The first group included subjects with "normal" glycaemic and insulinaemic responses during a 75 g oral glucose tolerance test. The second group was composed of subjects either with a high glucose response or high insulin response or both. Men included in the second group were different from the "normal" subjects for almost all body fatness variables. They also presented a prevalence of a positive family history of diabetes which was significantly higher than "normal" subjects. The second group was then divided into three distinct subgroups based on insulin and glucose responses of the subjects during the oral glucose tolerance test. Subjects with high insulin but "normal" glucose responses were characterized by significantly higher levels of total body fat and deep abdominal adipose tissue when compared to the "normal" group (p less than 0.05). Men with both high insulinaemic and glycaemic responses displayed higher body fatness values and higher deep and subcutaneous abdominal adipose tissue areas (p less than 0.05) in comparison with "normal" subjects. They also had a higher body mass index at age 20 years than control subjects and subjects with high insulin but "normal" glucose responses.(ABSTRACT TRUNCATED AT 250 WORDS)