Hypothyroidism among pediatric patients with type 1 diabetes mellitus, from patients' characteristics to disease severity.

We performed this study to evaluate the associations of hypothyroidism with clinical severity and the occurrence of diabetic ketoacidosis (DKA) at initial diagnosis among pediatric patients with type 1 diabetes mellitus (T1DM). 330 children with T1DM who referred to Diabetes Clinic were enrolled. The medical records were e valuated and a blood sample was drawn from patients for measuring thyroid function and antibodies, blood glucose, and glycated hemoglobin (HbA1C) levels. Hypothyroidism was detected in 9.6% of children with T1DM and was associated with higher rates of DKA (OR = 3.15, 95%CI = 1.48-6.71) and younger age at initial diagnosis (7.3 ± 3.2 vs. 10.1 ± 2.5, p = 0.04), higher levels of HbA1C upon enrolment (9.8 ± 2.2 vs. 8.8 ± 1.9, p = 0.02) and the requirement for higher insulin doses to control the disease (0.9 ± 0.42 vs. 0.81 ± 0.2, p = 0.03) compared to children with T1DM and normal thyroid function. Additionally children with T1DM and hypothyroidism had significantly higher rates of anti-TPO antibodies (p < 0.001), consanguinity in their parents (p =0.01), and family history of diabetes mellitus (p = 0.02) in their first degree relatives. In conclusion autoimmune hypothyroidism is prevalent among children with T1DM and is associated with a more aggressive disease at initial presentation, poorly controlled T1DM, and requirement for higher Insulin doses for controlling the disease.