Prevalence of thyroid disorders is not different in type 2 diabetes mellitus compared to nondiabetics in South India

Studies on thyroid disorders in type 2 diabetes mellitus (DM) are fewer than those in type 1 diabetes, but data from different parts of the world have shown conflicting results. To look at the prevalence of thyroid disorders in type 2 DM and nondiabetic controls separately in a community cohort and a hospital cohort from the same locality in South India. Thyroid function tests and thyroid autoantibodies were done in 986 people in the community (258 diabetics and 634 nondiabetics). In the hospital cohort of 194 people (147 diabetics and 47 nondiabetics), an ultrasonography of the neck was done in addition. Thyroid dysfunction was more common in the community compared to the hospital cohort 15.9 vs 9.6% but there was no difference in the proportion of people with thyroid dysfunction in diabetics and nondiabetics in both the community and the hospital cohorts. (15.6 vs 16.2% in the community and 9.6 vs 6.3% in the hospital in diabetics and nondiabetics respectively). Clinical goiter and sonographically detected goiter were also similar in diabetics and nondiabetics in the community and the hospital cohorts respectively. Females had more prevalence of goiter irrespective of the presence of diabetes. Commonest thyroid dysfunction was hypothyroidism and subclinical hypothyroidism in both cohorts. This unique study conducted in a community and hospital cohort from the same locality showed that the prevalence of thyroid disorders is similar in type 2 diabetic and nondiabetic subjects in our population.