Prevalence of Thyroid Dysfunction in Patients with Type 2 Diabetes Mellitus in Mumbai, Maharashtra, India: A Cross-sectional Study

Abstract

Introduction: India bears a high burden of Type 2 Diabetes Mellitus (T2DM) and Thyroid Dysfunction (TD). Though the coexistence of T2DM and TD has been evaluated, such studies from the perspective of metropolitan cities, including Mumbai, are lacking. Aim: To assess the prevalence of TD in patients with T2DM and to evaluate the association of TD with glycaemic control, duration, and complications of T2DM. Materials and Methods: The present observational cross-sectional study was performed in the Department of General Medicine, The Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India, from January 2016 to December 2017. The study involved 220 diagnosed patients with T2DM, of either gender, aged 18 years or more. All patients were evaluated for TD by performing thyroid profile {T3, T4 and Thyroid Stimulating Hormone (TSH)}. The association of TD prevalence with age, gender, Body Mass Index (BMI), duration of T2DM, Glycated Haemoglobin (HbA1c), and complications was assessed. The qualitative and quantitative parameters were compared with Chi- square and independent sample t-test, respectively, with a p-value <0.05 considered statistically significant. Results: The patients were predominantly males, 127 (57.7%) with a mean±Standard Deviation (SD) age and BMI of 63.4±14.02 years and 25.9±4.5 Kg/m2, respectively. The prevalence of TD was 36.8%. The predominant TD in patients with T2DM was subclinical hypothyroidism (75.9%). TD was significantly associated with advancing age (p-value=0.0167). However, gender and BMI were not significantly associated with TD. Poor glycaemic control was significantly associated with subclinical hypothyroidism (p-value=0.0255). The duration of T2DM was significantly associated with the prevalence of subclinical hypothyroidism (p-value=0.0144), primary hypothyroidism (p-value=0.0257), and subclinical hyperthyroidism (p-value=0.0310). TD was found to be significantly associated with both micro and macrovascular complications of T2DM (all p-values <0.05). Conclusion: In Mumbai, the prevalence of T2DM-associated TD was 36.8%. TD was significantly associated with advancing age, duration of T2DM, high HbA1c levels, and both micro and macrovascular complications.