ABSTRACT
Both diabetes mellitus and thyroid disorders are common in the general population. A lot of studies in different countries have tried to estimate the prevalence of thyroid disorders among type-2 diabetics. The aim of our work was to evaluate thyroid function, autoimmunity and morphology among patients with type-2 diabetes attending medical clinics at National Institute of Diabetes and Endocrinology [NIDE]. The study subjects included 250 type-2 diabetics and 50 healthy non-diabetic persons of matched age and gender who were recruited from medical clinics of [NIDE]. Routine and related specialized investigation [HbA1c, lipids profile, thyroid function tests and anti-thyroid autoantibodies] and thyroid ultrasound were done for all study subjects. Both thyroid dysfunction [13.1%] and abnormal thyroid ultrasound findings [47.6%] were significantly higher among diabetic patients than control subjects with higher frequency among females than males. The ratio of frequency of thyroid dysfunction in females to males was [14.7%: 7.5%], while the abnormal thyroid ultrasound findings female to male ratio was [51.5%: 34.5%]. Thyroid autoimmunity was comparable among both type-2 diabetics and control subjects. Hypothyroidism [subclinical 6.3% and overt 3.4%] was the most common thyroid dysfunction and nodular [multinodular and solitary] disorders were the most frequent abnormal thyroid morphology among diabetic subjects. While female sex, fasting plasma glucose, LDL, freeT4 and free T3 were associated with TSH [as a marker of thyroid dysfunction], linear regression revealed that the fasting plasma glucose, free T4 and free T3 were the independent risk factors for thyroid dysfunction. High prevalence of both thyroid dysfunction and abnormal thyroid morphology were determined among type-2 diabetics. These conditions not only occurred more frequently among female than male diabetics but also were associated with comparable lipid profile to non-diabetics. The frequency of thyroid autoimmunity was high among type-2 diabetics with thyroid dysfunction denoting the important role of autoimmunity in development of thyroid dysfunction among type-2 DM. Hypothyroidism [subclinical and overt] was the most common type of thyroid dysfunction while nodular [multinodular and solitary] disorders were the most abnormal thyroid morphology reported among these patients. The fasting plasma glucose, free T4, free T3 and anti-TPO antibodies were predictors for thyroid dysfunction while patient's age was the only predictor of abnormal thyroid morphology