Correlation between thyroid autoantibodies and intracranial arterial stenosis in stroke patients with hyperthyroidism

We performed a retrospective case review of stroke patients with diagnosis of hyperthyroidism admitted in our hospital from January 2008 to December 2010. We reviewed their routine assessments of intracranial and extracranial arteries or heart and then compared the demographic profiles, thryroid function test, and thyroid autoantibody status between stroke patients with and without intracranial stenosis. We also compared the baseline characteristics, thyroid function test (TFT), and prevalence of intracranial arterial stenosis between patients with or without elevated TPO-Ab level. We use the Wicoxon rank sum test for nonparametric and Fisher's exact test for categorical comparisons. A total of 17 acute ischemic stroke patients with hyperthyroidism were included and 8 (47.0%) patients was found to have intracranial stenosis. The patients with intracranial stenosis had a higher prevalence of elevated antithyroperoxidase antibody (TPO-Ab), compared with those without intracranial stenosis (100% versus 33.3%, p=0.004), while thyroid function tests were not significantly different between two groups. So we come to the conclusion that elevated thyroid autoantibody, especially TPO-Ab, is associated with the development of intracranial stenosis in hyperthyroid patients and therefore monitoring of intracranial vessels is suggested in hyperthyroid patients with high level of thyroid autoantibodies.