Serum levels of glucagon-like peptide (GLP)-1 and GLP-2 in patients with Hashimoto's thyroiditis

BACKGROUND The influence of Hashimoto's thyroiditis (HT) with subclinical hypothyroidism or euthyroid status on the alteration of glucagon-like peptide (GLP)-1 and GLP-2 levels remains uncertain. MATERIALS AND METHODS Twenty-four untreated HT patients with subclinical hypothyroidism, 24 euthyroid HT patients, and 24 age- and gender-matched controls were enrolled in the study. The levels of GLP-1, GLP-2, glucose, glycated albumin, insulin, thyroid hormone, and thyroid autoantibodies were measured and evaluated. RESULTS The levels of GLP-1, blood glucose, and triglyceride were higher in HT patients with subclinical hypothyroidism than in controls (all P < 0.05, respectively). However, the above variables, including GLP-2, were similar in euthyroid patients and controls. Neither GLP-1 nor GLP-2 was correlated with thyroid hormone, thyroid autoantibodies or metabolic parameters. CONCLUSION The serum levels of GLP-1, not GLP-2, were increased in patients with subclinical hypothyroidism. Our data suggest that subclinical hypothyroidism affects circulating GLP-1 levels.