Thyroid volume in patients with glucose metabolism disorders.

Objective: Thyroid volume and the prevalence of thyroid nodules are higher in patients with insulin resistance. A relationship between thyroid volume and glucose metabolism disorders (GMD) has not as yet been clarified. The present retrospective study aimed to investigate the association between GMD and thyroid volume.

Subjects and methods: We investigated the data of 2,630 patients who were evaluated for thyroid biopsy in our hospital. The study population included 602 patients with GMD, 554 patients with diabetes mellitus (DM) and 1,474 patients with normal glucose metabolism as a control group. We obtained the levels of serum thyroid stimulating hormone (TSH) and the thyroid volumes of those patients retrospectively.

Results: The median ages for the control group, GMD group and DM group were 55 (15-91) years, 60 (27-97) years, and 65 (27-91) years respectively and there was a statistically significant difference between the groups with regard to age and gender (p<0.001). Levels of TSH were similar in all groups. The median total thyroid volumes for patients with DM and GMD were significantly higher than that of the control group [22.5 (3-202) mL, 20.2 (4-190) mL, and 19.2 (3-168) mL respectively, p≤0.001 for all parameters]. Also the median total thyroid volume for patients with DM was significantly higher than that of the GMD group (p<0.001). According to the correlation analysis, thyroid volume was significantly correlated with age (r=0.92, p<0.001) and TSH (r=0.435, p<0.001). Age, gender, TSH levels, GMD and DM diagnosis were independently correlated with thyroid volume.

Conclusion: The thyroid gland is one of the target tissues of metabolic disorders. We reported a positive correlation between GMD/type 2 DM and thyroid volume. Further controlled, prospective, randomized studies on this subject are required to gain more information.