Plasma levels of resistin and ghrelin before and after treatment in patients with hyperthyroidism.

OBJECTIVE: To investigate ghrelin and resistin concentrations in patients with hyperthyroidism before and after restoration to a euthyroid state and to correlate the 2 peptides with anthropometric and insulin resistance parameters.
METHODS: The study included hyperthyroid patients and euthyroid healthy participants as a control group. Hyperthyroid patients were evaluated at the start of the study and after normalization of thyroid function with appropriate antithyroid drugs. Anthropometric parameters, insulin resistance parameters (fasting blood glucose, fasting insulin, and homeostasis model assessment-insulin resistance), thyroid function tests, and measurement of ghrelin and resistin were assessed in patients and control participants.
RESULTS: The study included 40 hyperthyroid patients (32 women and 8 men, aged 26-42 years) and 30 euthyroid healthy participants (20 women and 10 men, aged 25-43 years) as a control group. In hyperthyroid patients, serum resistin levels and insulin resistance parameters were higher and plasma ghrelin levels were lower than in control participants (P<.001), and all normalized after treatment. Ghrelin levels were correlated only with insulin resistance parameters, but no correlations with any anthropometric or laboratory data were found. Resistin levels did not correlate with any clinical or laboratory data of hyperthyroid patients.
CONCLUSION: In hyperthyroid patients, resistin was increased and ghrelin was decreased, they were not related to anthropometric parameters, and they normalized after treatment of hyperthyroidism.