IDENTIFICATION OF EARLY METABOLIC DEFECTS IN DIABETES-PRONE AUSTRALIAN ABORIGINES

The aim of the present study was to identify in young, diabetes-prone subjects the early abnormalities which may predispose to the development of type 2 diabetes. We studied 10 full-blood Australian Aborigines all of whom had a family history of diabetes and who were from an urbanised community with a high prevalence of this disorder. They were compared to 10 age- and body-mass-index-matched Caucasian controls with no family history of diabetes. Glucose kinetics were measured basally and following an oral glucose load. Fasting plasma glucose was equal in the two groups, but 2 h following the 75 g glucose load, the Aboriginal subjects had higher glycaemia than the controls (P < 0.01). Insulinaemia was higher in the Aborigines both basally and following the glucose drink (P < 0.05). Despite the hyperinsulinaemia, hepatic glucose production was higher in the Aboriginal subjects (P < 0.01), while metabolic clearance rate was lower. It is concluded that in young Australian Aborigines with a strong family history of type 2 diabetes, both hepatic and peripheral insulin resistance are early abnormalities.