Endocrine Abstracts

Objective: to assess the effects of associated autoimmune diseases on diabetes control, growth, lipid profile in children with type 1 diabetes mellitus (T1DM) and to determine the most predictive genetic, immune and metabolic risk factors of polyglandular autoimmunity in children with T1DM.

Material and Methods: 89 children with combined autoimmune pathology (main group, age 11.82 ± 3.68 years) and 100 patients with isolated T1DM (control group, age 10.91 ± 3.28 years) were recruited. Groups were comparable in age (P = 0.09) and T1DM duration (P = 0.99). Assessment of anthropometric parameters; biochemical blood parameters; glycosylated hemoglobin (HbA1c), vitamin D, thyroid hormones and antibodies to thyroid peroxidase (anti-TPO), to tissue transglutaminase IgA (tTGA) and to glutamate decarboxylase (GAD) levels was carried out. The assessment of height and body mass index (BMI) was carried out using the z-criterion (who, 2007).

Results: In the main group 42 children had combinations of T1DM with autoimmune thyroiditis (AIT), 15 - celiac disease (CD), 2 – Graves’ disease, 3 – AIT and CD, 27 – elevated anti-TPO-antibodies. BMI and height z-scores in both groups corresponded to the mean age values and didn’t differ significantly (P = 0.47 and 0.28 respectively). HbA1c level in children with combined autoimmune pathology was higher than in the control group (7.99 ± 1.74% vs 7.49 ± 1.30%, P = 0.029). Both groups demonstrated similar values of biochemical blood parameters: lipidogram, serum iron, and ferritin (P>0.05). Higher levels of anti-TPO antibodies were revealed in the main group (253.08 ± 308.06 IU/ml) compared to the control group (32.07 ± 28.83 IU/ml, P = 0.003). Among the risk factors for autoimmune thyroid damage, the association of thyroid pathology with vitamin D deficiency has been established (χ² = 4.79, P = 0.029, odds ratio (OR) 3.23, 95% confidence interval (CI) 1.10–10.46). Tendency to a higher risk in female patients (OR 1.64, CI 0.87–3.12), and with a high levels of GAD antibodies (OR 2.00, CI 0.89–10.52) was detected. The analysis of risk factors for CD revealed a tendency to an increased risk in patients with autoimmune thyroid disease (OR 1.463 (CI 0.606–3.530)), elevated levels of GAD (OR 2.514 (CI 0.892–7.085)). There was no association of CD risk with age of manifestation and duration of T1DM.

Conclusions: 1. Higher levels of HbA1c were detected in children with polyglandular autoimmune pathology.

2. Higher risk of autoimmune thyroid disease was found in patients with vitamin D deficiency. Potential risk factors for thyroid pathology include high levels of GAD antibodies, presence of gluten enteropathy, female gender and late puberty, and for CD – high levels of GAD antibodies.