Endocrine Abstracts

JOINT1262

Introduction.: Autoimmunity is the major cause of classical type 1 diabetes mellitus (T1DM) as well as heterogenic forms – latent autoimmune diabetes in adults (LADA) and latent autoimmune diabetes in youth (LADY). These categories of diabetes share biochemical markers of β-cell–directed autoimmunity with classical T1DM but also have main features of type 2 diabetes (T2DM) like slowly progression and insulin resistance. In clinical practice, autoimmunity in classical T1DM as well as in LADA and LADY is usually documented by antibodies against glutamic acid decarboxylase (antiGAD) to prevent misdiagnosis in these categories of patients.

The aim of the study.: To compare features of carbohydrate metabolism in patients with different types of autoimmune diabetes mellitus (DM).

Material and methods.: 71 patients with autoimmune DM were examined: 20 patients with classical type 1 DM (T1DM), 36 – with latent autoimmune diabetes in adults (LADA) (18 – LADA1 phenotype and 18 – LADA2), and 15 patients with latent autoimmune diabetes in youth (LADY). In addition to anamnesis data and general clinical research methods, indicators of carbohydrate metabolism (fasting glycemia, glycated hemoglobin (HbA1c)), and C-peptide level were evaluated.

Results.: The average age of manifestation of classical T1DM was 19 years, while in LADA1 it was 40.5 years, in LADA2 – 41, and in LADY – 20 years. Body mass index was in the normal range in patients with classical T1DM and LADY (21.99 and 23.39 kg/m² respectively), while in patients with LADA overweight was registered. Fasting plasma glucose level and HbA1c were recorded in the range from 9.22 to 9.90 mmol/l and 8.5% to 8.85% respectively and did not differ depending on the group. C-peptide level was 0.1 [0.10;0.15] and was significantly lower in patients with classical T1DM: by 6.4, 5 and 6.2 times compared with the LADA1, LADA2 and LADY respectively. HOMA-IR was the highest in patients with LADA2, but did not significantly differ from the LADA1 and LADY levels. AntiGAD level was the highest in classical T1DM and LADY groups (341.75 IU/ml and 270 IU/ml respectively); in LADA1 group the average level was 214.20 IU/ml and 95.50 IU/ml in LADA2, which significantly differ from two previous groups (р<0.05).

Conclusions.: Autoimmunity plays a major role in establishing the correct diagnosis of the type of diabetes mellitus and can prevent a misdiagnosis.