A study on prevalence of hypothyroidism in Type-II diabetes mellitus and correlation of Hba1c levels with TSH levels

Background: Thyroid diseases and Diabetes Mellitus are the two most common endocrine disorders encountered in clinical practice. Diabetes and Thyroid disorders have been shown to mutually influence each other and an association between both conditions has been reported in literature. This study aims to estimate the prevalence of Thyroid dysfunction among patients with TYPE-II Diabetes Mellitus and correlation of HbA1C levels with TSH levels.

Methods: 55 Patients coming with history of type 2 Diabetes Mellitus with or without history of hypothyroidism of more than 3 years duration or patients on treatment for hypothyroidism with history of diabetes mellitus presenting to OPDs or admitted in wards from May 2023 to December 2024 are included in the study. Patients are subjected to symptom analysis, clinical examination, blood investigations including HbA1C and TSH levels.

Results: The study found that the prevalence of hypothyroidism in diabetes patients was 12.7%. Specifically, 48 out of 55 diabetes patients were found to be non-hypothyroid, also known as euthyroid, representing 87.3% of the total sample. The study demonstrates a significant association between hypothyroidism and poor glycemic control in patients with T2DM. Hypothyroid patients had higher FBS, PPBS, and HbA1c levels, indicating a potential impact of thyroid dysfunction on diabetes management. The study also confirms that thyroxine treatment improves metabolic parameters in hypothyroid patients, emphasizing the need for integrated thyroid and diabetes care.

Conclusion: The study demonstrates that individuals with hypothyroidism tend to have higher average TSH-after thyroxine levels compared to those with normal thyroid function, consistent with several previous studies. These findings underscore the challenges in managing thyroid dysfunction in patients with T2DM and highlight the need for individualized treatment strategies to achieve optimal thyroid function and glycemic control. Further research is needed to explore the factors contributing to elevated TSH-after thyroxine levels in hypothyroid patients and to evaluate the impact of optimized thyroid hormone replacement on metabolic outcomes in this population.