Thyroxine (T4), triiodothyronine (T3), reverse T3 (rT3) and HbA1c were assayed in 21 insulin-dependent (type 1) diabetics and in 45 non-insulin-dependent (type 2) diabetics with normal thyroid function and different levels of control, and were compared to values found in apparently healthy controls. rT3 and rT3/T3 ratio were significantly increased both in type 1 and type 2 diabetics. T3 and T4 were significantly lower in type 2 diabetics than in the controls. Significant positive correlations of HbA1c to rT3 (r = 0.63) and to rT3/T3 ratio (r = 0.53) were found in type 1, and in type 2 diabetics (HbA1c, rT3-r = 0.50), (HbA1c, rT3/T3-r = 0.37). There was no correlation between glycemia (BG), relative body weight (RBW) and thyroid hormones. These data suggest that the alterations of thyroid hormones in type 1 and type 2 diabetes mellitus reflect the degree of control better than the hyperglycemia and the duration of metabolic unbalance.

Adolescent↗

PubMedDate not supplied

Residual B-cell function in type 1 (insulin-dependent) diabetes mellitus: its relation to clinical and metabolic features.

The aim of the present study was to investigate whether or not residual B-cell function could be related to insulin sensitivity as well as to duration of disease, insulin requirement, and indices of metabolic control in a population of Type 1 (insulin-dependent) diabetic patients. A positive correlation was found between fasting C-peptide and age at onset of diabetes, whereas a negative relationship occurred between C-peptide and duration of disease. Fasting C-peptide negatively correlated also to mean daily plasma glucose, 24-h glycosuria, and fasting free fatty acid concentration. Moreover, a negative correlation was found between C-peptide and daily insulin requirement. Conversely, a positive relationship occurred between C-peptide levels and the parameter we used for estimating insulin sensitivity, i.e. glucose disappearance rate after i.v. insulin injection. These results once more emphasize the importance of residual B-cell function in Type 1 (insulin-dependent) diabetes mellitus, and suggest that the residual endogenous insulin secretion might play an important role in glucose homeostasis of Type 1 diabetes by influencing the sensitivity to insulin.

Adolescent↗

PubMedDate not supplied

Insulin release in hyperuricemic patients.

The insulin response to oral glucose and to i.v tolbutamide was stuied in a group of hyperuricemic subjects and in a group of weight-matched controls. Glucose tolerance was impaired only in obese hyperuricemic subjects. Insulin response to oral glucose was enhanced in hyperuricemic subjects. Tolbutamide gave rise to a sharp increase in IRI levels already 2 min after the injection and this rise was significantly higher in hyperuricemic subjects than in controls. The same result was observed also after i.v. fructose. The interpretation of these data is not easy. Uric acid plasma level and obesity do not seem to be directly involved because an abnormal IRI response has been observed also after a rapid fall in uric acid plasma level after allopurinol treatment and is evident also in lean subjects. In our opinion the problem is more complex and must be considered from the point of view of a change involving carbohydrate as well as purine metabolism.

Adolescent↗