Diagnose of Diabetes
Type 1 Diabetes
Type 1 diabetes manifests itself through the four warning signs of excessive thirst, frequent urination, fatigue and weight loss and is usually rapidly diagnosed. However, these symptoms can be overlooked or misinterpreted in some cases and can lead to a dangerous metabolic decompensation known as diabetic ketoacidosis (DKA). Particularly in children, type 1 diabetes is often only diagnosed after ketoacidosis has occurred.
Research news: Screening for Autoantibodies Can Prevent Metabolic Decompensation
Islet autoantibodies can be detected in the blood long before clinical symptoms of type 1 diabetes appear. General screening for the presence of these autoantibodies in children makes it possible for the first time to diagnose type 1 diabetes early and in presymptomatic stages at a population level. This innovative approach was successfully tested in the Fr1da study and has the potential to prevent dangerous metabolic decompensation at the onset of the clinical disease.
Type 2 Diabetes
Type 2 diabetes often remains undetected for a long time. The symptoms are usually non-specific and develop gradually, meaning that they are not perceived by affected individuals. They become accustomed to the symptoms, without perceiving them as pathological. As a result, it can even take up to ten years for type 2 diabetes to be recognized and complications may have developed as a result of the permanently elevated blood sugar values.
Check-Ups are Important: In order to detect type 2 diabetes at an early stage, it is important to go for regular check-ups. In the process, blood sugar is also measured as a crucial diagnostic criterion. Elevated blood sugar values that do not yet meet the definition criteria for diabetes can indicate prediabetes. Diabetes-specific complications can already develop at this stage.
Research news: Identification of Prediabetes Subtypes
To be able to diagnose prediabetes more precisely, studies by the DZD included additional variables (e.g., liver fat, body fat distribution, genetic risk) and identified six different subtypes of prediabetes: three low-risk and three high-risk subtypes. These should be taken into account in the further treatment of people with an increased risk of diabetes, as people with high-risk subtypes require closer monitoring than those with low-risk subtypes and also benefit more from lifestyle interventions.
Research news: People with High-Risk Prediabetes Benefit from Intensive Lifestyle Intervention
Blood Sugar Measurements at the Doctor’s Office
The doctor diagnoses diabetes mellitus on the basis of blood values. The parameters for the diagnosis are:
Fasting Blood Sugar
Fasting blood sugar or fasting blood glucose is measured in the morning before breakfast.
- Values indicating prediabetes: 100–125 mg/dl or 5.6–6.9 mmol/l
- Values indicating diabetes: ≥126 mg/dl or ≥7.0 mmol/l
Random Blood Sugar
A random blood sugar of ≥200 mg/dl or ≥11.1 mmol/l indicates the presence of diabetes.
Oral Glucose Tolerance Test
During an oral glucose tolerance test, the patient drinks a liquid containing 75 g of sugar. Blood sugar is measured before consuming the glucose solution and two hours afterwards.
- 2-hour glucose value indicating prediabetes: 140–199 mg/dl or 7.8–11.0 mmol/l
- 2-hour glucose value indicating diabetes: ≥200 mg/dl or ≥11.1 mmol/l after 2 hours
HbA1c Value
HbA1c (glycohemoglobin) is the pigment in red blood cells that has inseparably bonded with sugar and can thus indicate the average concentration of blood sugar over the last six to eight weeks. This value is therefore also referred to as saccharified hemoglobin or the blood sugar memory. An
- HbA1c level indicating prediabetes: 5.7–6.4% or 39–47 mmol/mol
- HbA1c indicating diabetes: ≥6.5% or ≥48 mmol/mol