Assessment of Thyroid Dysfunction and Thyroid Auto-Antibodies in Type 1 Diabetes

Background and Objective: To investigate the association between thyroid dysfunction, thyroid autoimmunity and type 1 diabetes mellitus, a sample of 146 type 1 diabetic patients were studied.Subjects and methods: All referrals to diabetes clinic in diabetes research center were screened for TSH/T3/T4 /T3Ru /HbA1c and Anti TG Ab, Anti Tpo Ab. For each patient, a questionnaire including variables such as time from diagnosis of Diabetes mellitus, age, gender, consumed hypoglycemic Drugs and type of diabetes were registered to determine association between thyroid dysfunction and each of these items.Results: Of all the diabetic patients 37.7% was known to have thyroid dysfunction. The most common forms were: subclinical hypothyroidism %13, hypothyroidism %8.9, hyperthyroidism %8.9, and subclinical hyperthyroidism %6.8. There was a significant difference between prevalence of thyroid dysfunction and gender (%40 of female, %30 of male, P=0.045). A significant difference was found between age and thyroid dysfunction in type 1 diabetes mellitus (P=0.001). There was no significant difference between HbA1C and Thyroid dysfunction.Positive TPo- Ab and TG- Ab were found in %60 and 42.9of patients respectively. There was a significant difference between time from diagnosis of diabetes mellitus (Type 1) and thyroid dysfunctions (P<0.05) Conclusion: Our prospective study confirms the association between thyroid dysfunction and type 1 Diabetes, and demonstrates the high prevalence of thyroid Auto Antibody in patients with type 1 Diabetes particularly women. We conclude that all patients with type 1 Diabetes mellitus should undergo annual screening with thyroid function tests.