Transient Thyroid Dysfunction in New-Onset Type 1 Diabetes: Reassessing Test Timing for Accurate Results

Objective: Type 1 diabetes mellitus (T1DM) is a prevalent chronic disease affecting children, necessitating ongoing care from multidisciplinary clinics. This study aimed to determine the prevalence of thyroid dysfunction in newly diagnosed T1DM patients, investigating long-term thyroid function through periodic monitoring. Materials and Methods: A retrospective cohort study utilized the medical records of pediatric patients with newly diagnosed T1DM. Extracted data included age at initial diagnosis, presenting clinical manifestations, standard laboratory findings, and thyroid function panel results. Results: The sample included 208 T1DM patients, with a higher proportion of males (54.8%) than females (45.2%). Initial assessment revealed that 69.2% of patients were euthyroid, 24.5% exhibited euthyroid sick syndrome (ESS), 5.8% compensated hypothyroidism, and 0.5% primary hypothyroidism. About 76.5% of patients initially diagnosed with ESS were euthyroid at the second visit. Analysis confirmed a significant difference in the distribution of euthyroid and ESS patients between the first and second visits (P < .001). Temporal analysis indicated that thyroid function tended to normalize within 1-2 weeks of the initial presentation. Conclusion: Tests should be performed within 1-2 weeks following clinical stabilization to evaluate thyroid function in newly diagnosed T1DM patients. However, patients with a history of thyroid disease, or those with clinical signs indicative of thyroid dysfunction, should undergo immediate testing at the time of diagnosis.