Thyroid Dysfunction in Type 2 Diabetic Patients and the Effect of Diabetes Duration and Anti-glycemic Medications on Mean TSH and A1c levels: A Retrospective study

ABSTRACT

Background: The association between type 2 diabetes mellitus and thyroid disorder is a well-recognized one, necessitating checking diabetic patient for the presence of thyroid abnormality. Objective: To check the presence of hypo or hyperthyroidism in a sample of type 2 diabetic patients and to see whether anti-glycemic medications have any effect on mean TSH and A1c levels. Methods: This is a retrospective study on records of 1341 type 2 diabetic patients in the Specialized Center for Endocrinology and Diabetes, Baghdad for a period of 3 months in 2019, data were taken from patient records software and analyzed the presence of hypo or hyperthyroidism. Results: Out of 1341 type 2 diabetic patients 108 have thyroid dysfunction (8%), 7% for hypothyroidism and 1% for hyperthyroidism. Mean TSH levels were significantly lower with diabetes duration>5 years in hypothyroid patients (p=0.032) and lower when metformin was included in the treatment of hypothyroidism (p=0.036). No such an effect was present in hyperthyroid patients. Conclusion: Thyroid disorders among type 2 diabetic patients are under-estimated in our country, mean TSH levels are lower in hypothyroid patients when their treatment included metformin and lower with diabetes duration more than 5 years.