Exenatide Treatment Reduces Thyroid Gland Volume, but Has No Effect on the Size Of Thyroid Nodules

Abstract

Context.Exenatide is a Glucagon-like Peptide-1 receptor agonist, which is widely used for type 2 diabetes mellitus (T2DM). Limited and conflicting results are present about the effect of exenatide on the thyroid gland.Objective. The aim of this study was to evaluate the effect of exenatide treatment on structural and functional features of the thyroid gland in patients with T2DM.Design. The study was a prospective study, performed between 2015 and 2017. The laboratory values and thyroid ultrasonography features were compared before and after exenatide treatment.Subjects and Methods. The study included 39 obese diabetic patients. After inclusion to the study exenatide was started and patients were followed up for 6 months. Total thyroid volume, thyroid function tests, serum carcinoembryonic antigen (CEA) and calcitonin levels, the size and appearance of thyroid nodules were compared between baseline and after 6 months of treatment.Results. Exenatide at a dose of 5μg bid was started, increased to 10 μg bid after 4 weeks. We found a statistically significant decrease in thyroid volume (p=0.043) and serum thyroid stimulating hormone (TSH) levels (p=0.007), whereas serum ATPO. ATGl, fT4, fT3, CEA and calcitonin levels did no change with 6 months of exenatide treatment. There were no significant differences in the size and appearance of the thyroid nodules with treatment. The thyroid volume decrease was not correlated with TSH, body mass index and HbA1c reduction.Conclusion. Exenatide treatment for 6 months decreased serum TSH levels and thyroid volume, but had no effect on thyroid nodules and serum CEA and calcitonin levels.

The GLP‐1 receptor agonist exenatide reduces serum TSH by its effect on body weight in people with type 2 diabetes

“…And, weight loss is associated with reduction in serum TSH levels 5‐7 . All the previous studies that evaluated the effect of treatment of people with type 2 diabetes and obesity with GLP‐1 RA therapies on thyroid function have demonstrated a significant reduction in serum TSH levels with no difference in FT4 or FT3 levels with GLP‐1 RA agents 7,19,20 . Compared to our analysis, however, these erstwhile studies included a smaller number of participants (ranging between 33 and 49), most had a shorter duration of follow‐up (ranging between 6 and 16 months), and did not include a comparator group.…”

“…[5][6][7] All the previous studies that evaluated the effect of treatment of people with type 2 diabetes and obesity with GLP-1 RA therapies on thyroid function have demonstrated a significant reduction in serum TSH levels with no difference in FT4 or FT3 levels with GLP-1 RA agents. 7,19,20 Compared to our analysis, however, these erstwhile studies included a smaller number of participants (ranging between 33 and 49), most had a shorter duration of follow-up (ranging between 6 and 16 months), and did not include a comparator group. One of these studies, that included 33 patients with type 2 diabetes and who were followed-up for 6 months, didn't find any significant relationship between reduction in body weight and serum TSH using univariate correlation analysis.…”

“…18 Previous studies have demonstrated that treatment with GLP-1 RA leads to a significant reduction in serum TSH levels and is also associated with weight loss. 7,19,20 These studies included a relatively small number of participants and/or had a short duration of follow-up of 6 months. Therefore, it remains unclear whether the reduction in serum TSH is a direct effect of the GLP-1 RA or related to reduction in body weight.…”

“…Exenatide is a GLP‐1 receptor agonist (GLP‐1 RA) which is approved for the treatment of type 2 diabetes mellitus (T2DM) and is associated with weight loss 18 . Previous studies have demonstrated that treatment with GLP‐1 RA leads to a significant reduction in serum TSH levels and is also associated with weight loss 7,19,20 . These studies included a relatively small number of participants and/or had a short duration of follow‐up of 6 months.…”

Implications of GLP-1 Receptor Agonist on Thyroid Function: A Literature Review of Its Effects on Thyroid Volume, Risk of Cancer, Functionality and TSH Levels

“…The literature suggests that GLP-1R activation may have an impact on thyroid hormone levels and, more generally, on thyroid function parameters, although the exact mechanism and outcomes are still being elucidated. However, several studies reported contrasting findings, with a decrease in thyroid-stimulating hormone (TSH) levels as a result of GLP-1R activation [ 39 , 40 , 41 ].…”