ABSTRACT
The DS is a highly prevalent clinical entity and primarily a lifestyle disease with significant morbidity and premature mortality. We hypothesized that thyroid dysfunction may be relevant to the DS. We studied thyroid function [total T3, total T4, TSH, basal and after 20 and 60 minutes of IV injection of 200 micro g TRH] in thirty five type 2 diabetic patients with DS, in addition to ten age and sex -, matched controls. Fasting serum insulin, S cortisol, S uric acid, and lipogram were also performed for all participants after complete clinical history taking and examination. Body mass index [BMI], Waist [W], hip [H], W/H ratio together with blood pressure measurements were significantly higher in patients than in controls [P<0.001 each]. Furthermore, S cortisol, S insulin and S uric acid were significantly higher in patients than in controls [P< 0.001 each]. In addition total cholesterol [TC], triglyceride [TG], and LDL were significantly raised in patients than in controls while HDL was significantly reduced in patients than in controls [P<0.001 each]. Basal T3, T4, and TSH were not different in patients and controls. However, following TRH injection particularly after 60 minutes, patients were classified into three groups; Group I which had normal thyroid function in 25 patients [71.4%], Group II which had sub-clinical primary hypothyroidism in 4 patients [11.4%], and Group III which had secondary hypothyroidism in 6 patients [17.2%]. All patients with group II and 5 out of 6 patients with group III were females. Moreover, TSH response to TRH injection after 60 minutes was correlated significantly positively with S cortisol [r=.477, P<0.01], S insulin [r=.743, P<0.01,], S uric acid [r=.335, P<0.05], TC [r=.317, P<0.05] and LDL [r=0326, P<0.05,] and correlated significantly negatively with HDL [r= -.341, P<0.05]. The clustering of metabolic abnormalities in DS suggested underlying hormonal disturbances not only in insulin but also in thyroid dysfiunction in the form of sub-clinical hypothyroidism and suspected disturbed hypothalamo - pituitary - adrenal axis. However such conclusions should be re- evaluated on a large number of patients aiming to elucidate a possible dysfunction of hypothalamo -pituitary-thyroid axis in DS