Influence of residual C‐peptide secretion on nocturnal serum TSH peak in well‐controlled diabetic patients

Abstract

These data indicate that the absence of residual pancreatic beta-cell function in patients with insulin-dependent diabetes mellitus is associated with neuroendocrine dysfunction in the regulation of circadian TSH secretion, which is not reversible after restoration of good glycaemic control.

Thyroid Disorders in Patients of Type 2 Diabetes Mellitus

“…those with totally absent pancreatic beta cell function [19]. In the present study HbA1c was found to be significantly increased in patients with diabetes, and it was directly proportional to the fasting blood glucose levels.…”

Thyroid Disorders and Diabetes Mellitus

“…This “low T3 state” could be explained by an impairment in peripheral conversion of T4 to T3 that normalizes with improvement in glycemic control. However, in a study by Coiro et al involving type 1 diabetes patients with absent residual pancreatic beta cell function, an amelioration in glycemic control did not restore the normal nocturnal TSH peak suggesting a diabetes-dependent alteration in the central control of TSH [90]. Higher levels of circulating insulin associated with insulin resistance have shown a proliferative effect on thyroid tissue resulting in larger thyroid size with increased formation of nodules [91, 92].…”

Influence of residual insulin secretion and duration of diabetes mellitus on the control of luteinizing hormone secretion in women

“…Previous studies have reported impaired LH responses to Gn-RH in CpN but not CpP patients with short-term (3 years) diabetes mellitus [8]. This phenomenon is part of a general abnormality in hypothalamic, anterior and posterior pituitary function (for review see Refs 8,[10][11][12][15][16][17] observed in CpN diabetic patients. The present results confirm these observations and show that a similar impairment affects naloxone-induced LH secretion.…”

“…Eleven subjects in group 1 (mean age Ϯ SE 29·8 Ϯ 1·4 years) and 11 subjects in group 2 (mean age 31·1 Ϯ 1·5 years) were CpP, whereas 11 subjects in group 1 (30·4 Ϯ 1·6 years) and 11 subjects in group 2 (32·0 Ϯ 1·8 years) were CpN. The inclusion criteria for CpP or CpN groups were decided by preliminary studies according to previous reports [8][9][10][11][12]. None of the diabetic and control subjects was affected by major affective disorders as determined by the Hamilton Depressive Rating Scale [13].…”