Laboratorydiagnosis of prediabetes

Prediabetes is the term used to describe the condition with impaired fasting glucose (IFG), glucose concentrations higher than normal but below the established threshold for diabetes, or impaired glucose tolerance (IGT) recognized based on the results of a 2-hour oral glucose tolerance test (OGTT). People with prediabetes are at high-risk for developing diabetes and associated complications. Occurrence of IFG and/or IGT is associated with abdominal or visceral obesity, high serum triglycerides and/or low HDL-cholesterol, hypertension. From the practical point of view, screening with HbA1c is easier to perform however, it was suggested that fewer cases of prediabetes are detected than with OGTT. It may be understandable as both measurements reflect different physiological processes. In the above presented studies the performance of hemoglobin A1c, advocated for the diagnosis of diabetes and prediabetes, has been assessed in corroboration with fasting plasma glucose (FPG) or with the combination of FPG and 2-hr OGTT glucose values. It is important to point out that HbA1c below 5.7% do not reliably exclude the presence of prediabetes. The above presented data support the idea for greater use of oral glucose tolerance tests in combination with FPG for diagnosis of dysglycemia.