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Diagnosing type 1 diabetes

Typical symptoms of high blood sugar include the need to urinate more, thirst, tiredness and weight loss.

Usually, the possibility of type 1 diabetes enters the frame on the back of symptoms caused by high blood sugar: person's urination increases, they feel thirsty and tired and they have weight loss. Typically, the blood sugar level is high, above 10–20 mmol/l. Symptoms typically develop and become worse over few days or weeks. The symptoms may take longer to develop in adults than in children.

Signs of of type 1 diabetes:

  • under the age of 40 when diagnosed

  • originally of normal weight or only slightly overweight

  • losing a lot of weight quickly

  • no clear metabolic syndrome

  • (close) family has type 1 diabetes

  • they have another autoimmune disease

At the time of diagnosis

At the time of diagnosis, the majority (over 80%) exhibit antibodies related to an autoimmune inflammation in the blood.

Normally, the onset of type 1 diabetes happens when approximately 20% of functional, insulin-producing beta cells remain. At that point, the remaining cells’ ability to produce insulin no longer suffices to maintain a normal blood sugar level, causing it to increase. Body’s insulin production can be examined on the basis of C-peptide in a blood test.

In severe insulin deficiency, the body breaks down the fat tissue, and the released fatty acids generate ketones. The ketone level in a blood sample is measured using a ketone meter or laboratory test. If the ketone level is high, there is a risk of ketoacidosis.

Temporary remission

After initiation of insulin therapy and when blood sugar levels normalize, the insulin secretion capacity of pancreatic beta cells often partially recovers temporarily. The need for injected insulin often decreases as the body's own cells become more active. This is called a remission. It can last from a few months up to a couple of years. However, it is only a temporary phase, and when remission ends, the body's own insulin production ceases permanently, and the need for insulin medication increases again.

Updated 30.9.2023