Comparison of Glucose Tolerance in Patients with Graves Disease Treated with Methimazole with Those who Have Received Radioiodine

One of the major concern of the administration of radioiodine is its complications. Pancras has sodium iodine symporter and may concentrate radioiodine. This study compared glucose tolerance in Graves disease patients on continuous treatment with antithyroid drugs, with those who received radioiodine.

In this study, 132 patients with Grave's disease who relapsed after drug therapy were randomly selected on by the patient preference for long-term treatment with either methimazole or radioactive iodine. In each group, fasting blood sugar, glucose tolerance test, and lipid profiles, TSH, insulin, HOMA-IR and HOMA-B were measured.

The two groups showed no significant difference in age sex, BMI and BP. Median FBS and HOMA-IR in the radioactive iodine group were higher than in the methimazole group (94 mg/dl vs. 90 mg/dl, P=0.019) and 1.5(1.2-2.3) vs. 1.3(0.8-2.1, P=0.045, respectively, but after adjustment there was no difference between the two groups; no significant difference was seen in HOMA-B, median two-hour blood glucose and serum insulin levels, between the two groups.

Results indicate no relationship between radioactive iodine treatment and glucose intolerance.