Introduction: Diabetes mellitus (DM) is fast spreading in developed as well as developing world. With improvements in socioeconomic status and a sedentary life style more and more people are getting affected at a relatively younger age. There are various studies which have reported that there is an increased incidence of thyroid abnormalities in patients with diabetes mellitus. Moreover, presence of thyroid abnormalities is associated with poor metabolic control. Therefore we conducted this study to compare thyroid function in patients with diabetes mellitus type II and healthy individuals.

Materials and Methods: This was a case control study in which 80 patients with Diabetes Mellitus Type II and 80 age matched healthy individuals were included on the basis of a predefined inclusion and exclusion criteria. A detailed history was taken in all the cases with particular attention on duration of diabetes mellitus and presence of other systemic illnesses. Patients were classified as to be having subclinical hypothyroidism (TSH- 4.5 to 10 and normal free T4), Overt hypothyroidism (TSH more than 10 with low free T4 levels), hyperthyroidism (TSH less than 0.45 and raised free T4) and subclinical hyperthyroidism (TSH less than 0.45 and raised free T4). For statistical purposes p value less than 0.05 was taken as statistically significant. 

Results: Out of total 160 individuals enrolled in this study there were 92 (57.50%) females and 68 (42.50%) males with a M:F ratio of 1:0.73. The age groups were found to be comparable and there was no statistically significant difference in mean age of both the groups (p=0.53). The comparison of the patients of both the groups on the basis of whether they had a normal or abnormal thyroid function test showed that patients with diabetes mellitus type 2 were more likely to be having abnormal thyroid function test as compared to healthy individuals and the difference was found to be statistically significant (p=0.043).

Conclusion: Thyroid abnormalities are more common in patients with diabetes mellitus type II as compared to age matched healthy individuals. It is therefor important from point of view of a treating physician to screen patients with DM type II for presence of thyroid function abnormalities.

Keywords: Diabetes Mellitus Type II, Thyroid function abnormalities, Free T4, TSH.

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Radhika Manjeshwar (M.B.B.S.)

Medical Officer, Primary Health Center Edu, Karnataka, India