Effect of radioactive iodine therapy on carotid intima media thickness in patients with hyperthyroidism

The aim of this study was to evaluate the carotid intima media thickness (IMT) in patients with thyrotoxicosis who received radioactive iodine (RAI) treatment.

This study was planned to be conducted with two different groups of people. There were 87 patients in the patient group and 98 controls. Participants were evaluated for atherosclerosis risk factors. Mean carotid IMT was measured from three consecutive traces at the common carotid artery bifurcation.

The mean carotid IMT was 0.81 ± 0.20 in patient group and this was higher than the controls (0.68 ± 0.19) (p < 0.01). IM thickening was positively correlated with the applied RAI dose levels in the treatment group (p = 0.029). In patients with only HT, the data of the two groups showed a significant difference, with the average IMT being higher in the patient group than that of the control group (p: 0.011).

RAI used in the treatment of thyrotoxicosis increases the IMT of carotid artery independent of age and sex. This treatment yields better results with higher doses, and this effect is more marked in patients with HT. Hence, we believe that it is necessary to calculate the dose properly for hyperthyroid cases in which treatment with RAI is planned. In particular, the patients with HT need to be treated with the minimum possible dose. Further, carotid arteries should be evaluated with US following RAI treatment.