Razi Journal of Medical Sciences

Background: Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease co-occurred with a high incidence of other autoimmune disorders including thyroid function abnormalities. This study investigated the prevalence of autoimmune thyroid disorders in patients with T1DM.

Methods: In this retrospective cross sectional study, 150 patients with T1DM aged 7 - 17 years old, admitted in Ali-Asghar and Hazrat-e-Rasool Hospitals during 2006 to 2011 were studied. The records of patients in terms of sex, age, age at onset of diabetes, duration of diabetes, HbA1c levels of patients and thyroid hormones T3, T4 and hormone TSH, thyroid antibodies such as anti-thyroid peroxidase (anti -TPO) and thyroglobulin antibodies (anti-Tg) were investigated. The collected data were analyzed using SPSS 11 software.

Results: Eighty two patients (54.7%) were female and 68 (45.3%) were male and their mean (SD) age was 11.5 ± 2.8 years. Anti-thyroid peroxidase antibody (anti-TPO) was positive in 41 patients (27.3%) and thyroglobulin antibody (anti-Tg) in 23 patients (15.3%) and in 16 patients (10.6%) anti-TPO and anti-Tg were positive simultaneously. Prevalence of clinical hypothyroidism (21.9%) and subclinical hypothyroidism (7.3%) in patients with positive anti-TPO were higher than patients with anti-TPO negative. The presence of anti-thyroid antibodies were associated with factors, including female gender, older age, longer duration of diabetes and higher levels of HbA1c.

Conclusion: According to high prevalence of autoimmune thyroid disorders in children with T1DM evaluating these patients in terms of thyroid function and thyroid auto-antibodies is suggested.