Impaired glucose tolerance (IGT)

This is a stage of impaired glucose regulation (Fasting plasma glucose < 7.0 mmol/l and OGTT 2-hour value >= 7.8 mmol/l but < 11.1 mmol/l). (1)

The risk of subsequent conversion to diabetes is about 4.7% per year in Caucasians and higher in some ethnic minority groups.

• these people should be followed up annually to reassess glucose regulation and all other cardiovascular risk factors

In 2010, the worldwide prevalence of glucose intolerance was about 8% (2)

Complications of impaired glucose tolerance include:

• cardiovascular disease - in middle aged men with glucose intolerance have double the risk of death from cardiovascular disease
• study evidence has revealed an increased mortality risk associated with IGT (3)
  • impaired glucose tolerance was associated with an increased mortality risk (HR 1.5, 95% CI 1.1 to 2.0)

Reference:

1. American Diabetes Association. 2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2018. Diabetes Care. 2018 Jan;41(Suppl 1):S13-S27.
2. Bansal N. Prediabetes diagnosis and treatment: A review. World J Diabetes. 2015 Mar 15;6(2):296-303
3. Barr EL et al. Risk of cardiovascular and all-cause mortality in individuals with diabetes mellitus, impaired fasting glucose, and impaired glucose tolerance: the Australian Diabetes, Obesity, and Lifestyle Study (AusDiab).Circulation. 2007 Jul 10;116(2):151-7