Summary and perspectives on impaired glucose tolerance

There is much evidence to link impaired glucose tolerance (IGT) with the risk of developing non-insulin dependent diabetes mellitus (NIDDM) and of cardiovascular disease. However, it is unclear whether IGT is merely a marker or a risk factor or whether it is causally related to the development of these conditions. It is also unclear whether all individuals with IGT have an equal probability of developing NIDDM or cardiovascular disease. The exact pathogenetic relationship between IGT and these disease has important implications for preventive therapy which might be offered to such people. Patient compliance, physician motivation and supportive health-care funding will be greater if IGT is seen to be a definite stage in the development of a serious disease rather than simply a risk factor with statistically defined predictive power. As yet, there are insufficient data to justify routine therapy of subjects with IGT but further research into this condition and the development of effective preventive therapies could lead to widespread treatment.