A RETROSPECTIVE STUDY ON THE THYROID DYSFUNCTION IN PATIENTS WITH TYPE 2 DIABETES MELLITUS AND THE EFFECT OF DURATION OF DIABETES AND ANTI-GLYCEMIC MEDICATIONS ON MEAN HBA1C AND TSH LEVELS

Background: The relationship between type 2 diabetes and thyroid disorders is well established and requires testing a diabetic patient for the presence of thyroid abnormalities. Aim: to check the presence of hypothyroidism or hyperthyroidism in a sample of patients with type 2 diabetes and to check if anti-glycemic drugs have any effect on average levels of TSH and A1c.

Methods: This is a retrospective study of the documentation of 1,341 patients with type 2 diabetes at the Endocrinology and Diabetology department of Services Hospital Lahore for one-year duration from March 2019 to March 2020. The data was taken from patient registration software and analyzed for the presence of hypothyroidism or hyperthyroidism.

Results: Out of 1,341 patients with type 2 diabetes, 108 had thyroid dysfunction (8%), 7% had hypothyroidism, and 1% had hyperthyroidism. Mean TSH levels were significantly lower with diabetes duration> 5 years in patients with hypothyroidism (p = 0.032) and lower when metformin was introduced to treat hypothyroidism (p = 0.036). In patients with hyperthyroidism, this effect did not occur.

Conclusion: Thyroid disorders in patients with type 2 diabetes are underestimated in our country, mean TSH levels are lower in patients with hypothyroidism when metformin was used, and lower in patients with diabetes lasting more than 5 years.

Keywords: Type 2 diabetes, Hypothyroidism, Hyperthyroidism, Metformin.