A Case-control Study Of The Association Between Thyroid Autoantibodies And Intracranial Large Artery Stenosis In Acute Ischemic Stroke

Objective: In recent years, some studies found that thyroid autoantibodies may be associated with intracranial artery stenosis.But most of the present studies which studied on the relationship of thyroid autoantibodies and intracranial artery stenosis didn’t excluded the effect of abnormal thyroid hormone levels on intracranial artery stenosis.This study aimed to investigate the association between thyroid autoantibodies and intracranial large artery stenosis in young and middle-aged acute ischemic stoke patients with completely normal throid hormones level.Methods:We conducted a retrospective case-control study. The included subjects were the patients with acute ischemic stroke who were admitted to the neurology department of The First Affiliated Hospital of Fujian Medical University and the neurology department of Fu Jian Provincial Hospital from January 2011 to December 2014.The age range of patients was limited to young and middle-aged people(18-64 years old) and their thyroid hormone levels were completely normal without antithyroid drugs or thyroid hormones therapies in the past.Based on the results of cerebral vascular imaging examinations(MRA/CTA/DSA),patients with any intracranial large artery’s stenosis rate more than fifty percent were classified as intracranial large stenosis group(Group ILAS), and the rest were non-intracranial large artery stenosis group(Group NIAS). We compared the baseline characteristics between the two groups and used multivariate logistic regression analysis to explore the relationship between antithyroperoxidase antibodies(TPOAb), antithyroglobulin antibodies(Tg Ab) and intracranial large artery stenosis.Results:A total of 301 subjects were included.The median age was 55.0 years old. 231 cases were males,accounting for 75.7%.According to Chinese ischemic stroke subclassification(CISS),large artery atherosclerosis was the main cause(69.8%) of ischemic stroke in admitted study objects.In the study,there were 116 cases(38.5%) in the ILAS group,185 cases(61.5%) in the NIAS group..In ILAS group,the most frequent location of ILAS was middle cerebral artery(40.78%).Univariate analysis showed that positive TPOAb was associated with intracranial large artery stenosis(P=0.003).Multivariate analysis showed that positive TPOAb was an independent risk factor of ILAS(OR:3.358,95%CI: 1.443-7.815, P=0.005).The study objects were further divided into TPOAb positive group and TPOAb negative group.Compared with TPOAb negative group,the probability of intracranial large artery stenosis involving middle cerebral artery was higher in TPOAb positive group(P=0.010).Conclusion: Positive TPOAb was an independent risk factor of intracranial large artery stenosis in young and middle-aged patients with acute ischemic stroke.In the young and middle-aged patients with acute ischemic stroke, abnormally elevated TPOAb significantly increased risk of intracranial large artery stenosis.Compared with patients with negative TPOAb,intracranial artery stenosis was more often involved in middle cerebral artery in patiets with positive TPOAb.It is necessary to undertake imaging examinations to evaluate intracranial arteries for young and middle-aged people with positive TPOAb,which may help to the early diagnosis and intervention of ischemic stroke.