GAD65 antibodies among Greenland Inuit and its relation to glucose intolerance

The aim of this study was to compare the prevalence of circulating Glutamin-Acid-decarboxylase 65 antibodies in a sample of Greenlanders (Inuit) with clinically verified diabetes with samples of participants from a population survey. The study population included participants with known diabetes from a population-based study (sample 1) and patients with clinically verified diabetes in Nuuk Greenland (sample 2). In addition, age- and gender-matched participants from the population study without known diabetes were categorized in groups with (1) normal glucose tolerance test, (2) with impaired fasting glycemia, (3) with impaired glucose tolerance and (4) with previously unknown diabetes based on oral glucose tolerance test and were enrolled in the study. Presence of circulating Glutamin-Acid-decarboxylase 65 antibodies were measured in all participants. A total of 484 persons were enrolled in the study. Six individuals had circulating Glutamin-Acid-decarboxylase 65 antibodies: four of them had known diabetes, one had impaired glucose tolerance and one normal glucose tolerance test. The prevalence of circulating Glutamin-Acid-decarboxylase 65 antibodies among Greenlanders with diabetes was 4.3 % and less than 1 % among Greenlanders without diabetes (p = 0.001). The prevalence of circulating Glutamin-Acid-decarboxylase 65 antibodies among Greenlanders with and without diabetes is relatively low in a global perspective in accordance with one former study among Inuit. Autoimmune diabetes seems to be uncommon in Greenland .