Very early changes in circulating T3 and rT3 during development of metabolic derangement in diabetic patients

Area of Science:

• Endocrinology
• Metabolic Disorders
• Thyroid Hormone Research

Background:

• Type 1 diabetes involves insulin deficiency, impacting metabolic regulation.
• Thyroid hormones, like triiodothyronine (T3) and reverse triiodothyronine (rT3), play crucial roles in metabolism.
• Insulin withdrawal in diabetic patients can precipitate metabolic decompensation.

Purpose of the Study:

• To investigate alterations in circulating iodothyronines during metabolic derangement in juvenile diabetics after insulin withdrawal.
• To compare these hormonal changes between patients with and without residual beta-cell function.

Main Methods:

• Studied 15 juvenile type diabetic patients.
• Measured circulating iodothyronines (T3, rT3) and C-peptide levels.
• Patients were categorized based on residual beta-cell function after insulin withdrawal.

Main Results:

• A decrease in serum T3 and an increase in serum rT3 were observed within 12 hours of insulin withdrawal.
• These thyroid hormone alterations and metabolic derangements were more pronounced in patients lacking residual beta-cell function.
• The presence of residual beta-cell function appeared to mitigate the severity of hormonal and metabolic changes.

Conclusions:

• Insulin withdrawal in juvenile diabetics significantly alters thyroid hormone levels, particularly T3 and rT3.
• Residual beta-cell function plays a protective role against severe thyroid hormone dysregulation and metabolic derangement in diabetic patients.
• These findings highlight the intricate relationship between insulin, thyroid hormones, and metabolic control in diabetes.