Impaired glucose tolerance, is a risk factor for progression to diabetes. The decline in glycemic control is not inevitable if intervention to correct the underlying defects that lead to glucose intolerance are addressed at an early stage. Both lifestyle interventions and pharmacological approaches have proved effective in preventing the progression from impaired glucose tolerance to type 2 diabetes.

If not controlled, postprandial hyperglycaemia contributes to insulin resistance and exacerbates hyperinsulinaemia. The increased need for insulin increases beta-cell stress. In the longer term, excessively elevated levels of post-meal glucose have been linked with increased cardiovascular morbidity and mortality.

Glucobay delays the progression from impaired glucose tolerance to diabetes

Until recently, the management of diabetes has focused on lowering fasting plasma glucose levels. However, it is becoming increasingly evident that elevated postprandial plasma glucose levels play an important role in the progression of glucose in tolerance established type 2 diabetes. IGT is a highly prevalent prediabetic state that is identified by excessive 2-hour postchallenge plasma glucose levels measured by an oral glucose tolerance test (OGTT).

The STOP-NIDDM was conducted to test the hypothesis that preventing postprandial hyperglycemia can prevent or delay the progression of glucose intolerance.

The multicentre Study to Prevent Non-insulin Dependent Diabetes Mellitus (STOP-NIDDM) randomized 1,429 individuals with chronic IGT (2hPG level 7.8 - 11.0 mmol/L and FPG 5.6 - 7.7 mmol/L) to receive acarbose or placebo for 3 years. Compared with placebo, acarbose was shown to significantly reduce the development of established diabetes by 25% based on a single oral glucose tolerance test (OGTT) (p=0.0015), and by 36% based on the stricter criterion of two OGTTs (Chiasson et al. 2002).

The results of the STOP-NIDDM are supported by a prospective, 3-year trial conducted in China (Wenying et al. 2001). The effects of acarbose, metformin, lifestyle modification (diet and exercise), and no intervention on progression to type 2 diabetes were observed in 321 in dividuals with IGT. Compared with the control group, the risk of type 2 diabetes was significantly reduced in the acarbose (87.8%, relative risk=0.122, p=0.0001) and metformin (76.8%, relative risk=0.232, p=0.0002) groups, but not in the lifestyle modification group (odds ratio=0.572, p=0.0928).

Chiasson et al., Diabetes Care 21: 1720-1725 (1998)
Chiasson et al., Lancet 359: 2072-2077 (2002)