RELATIONSHIP OF GLYCEMIC CONTROL WITH THYROID HORMONE LEVELS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

Abstract

Objective: To compare the results of thyroid function tests in euthyroid type
2 diabetic patients and normal healthy individuals on the basis of glycemic
control.
Methodology: This case control study of 300 subjects; 150 with type 2 diabetes
and 150 controls, paired by age and gender, was conducted at two teaching
hospitals of Peshawar during February-July 2013. They were sampled to investigate
the relationship of thyroid hormones with glycemic profile determinants.
Fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) were measured.
The concentration of thyroid stimulating hormone (TSH), total triiodothyronine
(TT3) and thyroxine (TT4) were evaluated using a Radioimmunoassay
procedure. Diabetics were further divided into 2 groups on the basis of their
good/poor glycemic control as shown by their HbA1c. P value of <0.05 was
considered significant for comparison.
Results: Serum concentration of TT3 and TT4 were significantly low and high,
respectively, in diabetic group as compared with healthy controls on the basis
of FPG and HbA1c (p <0.05). While comparing diabetics on the basis of glycemic
control, both TT3 and TT4 were significantly low in the group with poor
glycemic control (p <0.05). Diabetics with poor glycemic control had a raised
mean TSH level (2.52 ±3.21) as compared with diabetics with good glycemic
control (1.68 ±1.13) but the difference was not statistically significant.
Conclusion: Patients with type 2 diabetes were associated with a low TT3 and a
high TT4 level, respectively, as compared to their normal controls in euthyroid
diabetic patients.