Impaired glucose tolerance and prediabetes
Impaired glucose tolerance (IGT) and impaired fasting glucose (IFG)are intermediate conditions in the transition phase of normality and diabetes, also referred to as prediabetes . Because there are no symptoms of IGT and IGF, many people have the condition and are unaware of it. Prediabetes as well as diabetes meet established criteria for conditions in which early detection is appropriate. Both conditions are common, are increasing in prevalence, and impose significant health burdens.
The American Diabetes Association (ADA) defines special categories at increased risk for diabetes (prediabetes):
- IGF as defined by a plasma glucose value of ≥140mg/dL and <200mg/dL (7.8mmol/L and <11.1mmol/L) after a 2–h oral glucose tolerance test (OGTT).
- IFG as defined by a fasting plasma glucose (FPG) ≥100 and ≤125 mg/dL (5.6-6.9 mmol/L).
- HbA1C 5.7-6.4%
People with IGT or IFG are at high risk of the progression to type 2 diabetes. (Figure 1) Both conditions are associated with obesity (especially abdominal or visceral obesity), dyslipidemia with high triglycerides and/or low HDL cholesterol, and arterial hypertension.
Importantly, the number of individuals with prediabetes considerably exceeds the number of individuals with overt diabetes.
In order to develop efficacious primary diabetes prevention options, prediabetes treatment clinical trials are needed. These should test the safety and efficacy of preventive measures and explore tools to early identify people at high risk for type 2 diabetes.
Prediabetes research
Profil has several methods to identify individuals who are at risk of diabetes. These range from the measurement of anthropometric parameters to the analysis of circulating markers implicated in the development of prediabetes and diabetes. Fasting serum insulin, fasting plasma glucose (with derived HOMA-B and HOMA-S) and oral glucose tolerance tests are commonly employed at Profil to serve as indicators of prediabetes. Insulin resistance (IR) is a classical feature of prediabetes. It may be present years before deterioration in blood glucose control becomes measurable. Profil uses the most accurate and reliable measure of insulin sensitivity: the hyperinsulinemic euglycemic clamp technique. Alternatively, measures of insulin sensitivity can be derived from meal tests or through the short Insulin Tolerance Test.
Recent evidence indicates an increase of liver fat as being another key factor predisposing obese people to the development of insulin resistance. Profil provides the measurement of liver fat directly using magnetic resonance spectroscopy (MRI-PDFF, or Fibroscan) or indirectly using the fatty liver index (FLI), which is a composite surrogate of gamma-glutamyltransferase, triglycerides, waist circumference and BMI. The FLI has been validated for indicating the presence of a fatty liver and a high FLI is associated with a high prevalence of insulin resistance (as assessed using the glucose clamp technique), elevated fasting plasma glucose and insulin levels, and impaired glucose tolerance.
