Thyroid dysfunction in patients with type 2 diabetes mellitus and its association with diabetic complications

Background and Aims: Patients with type 2 diabetes mellitus are more prone to thyroid disorders. Hypothyroidism in them leads to an aggravation of microvascular complications. Diabetic patients with hypothyroidism also are at an increased risk of cardiovascular disease. Screening for thyroid dysfunction in diabetic patients will allow early treatment of hypothyroidism. The aim of this study was to assess the level of thyroid dysfunction in patients with type 2 diabetes mellitus and to identify the association of thyroid dysfunction with diabetic complications. Methods: This is a cross-sectional study that was conducted at departments of Medicine & Endocrinology in JIPMER, Pondicherry, between June 2016 and May 2019. 331 patients with type 2 diabetes mellitus attending the out-patient department without any prior history of thyroid disease, chronic liver disease or acute illness were recruited for the study. All subjects were screened for diabetic complications (nephropathy, neuropathy, retinopathy & cardiovascular disease). Thyroid function test was done in all subjects using chemiluminescent immunoassay method. Results: Hypothyroidism was seen in 13.9%, while hyperthyroidism was observed in 3.6% of the study subjects. Thyroid dysfunction was more common among females than males. No correlation was seen between thyroid dysfunction and diabetic complications in the study subjects. Conclusion: The prevalence of thyroid dysfunction is 17.5% in patients with type 2 diabetes mellitus. Thyroid dysfunction did not have any correlation with diabetic complications.