Elevated Thyroid Autoantibodies Aggravate Stroke Severity in Euthyroidism with Acute Ischemic Stroke

Abstract

Introduction. Studies have indicated that immune reactions contribute to endothelial dysfunction and atherosclerosis. It is unclear whether thyroid dysfunction or elevated thyroid autoantibodies are associated with atherosclerosis. Therefore, we investigated the influence of thyroid autoimmunity related to elevated thyroid autoantibodies on functional outcome in euthyroidism with acute ischemic stroke (AIS). Methods. All patients with AIS underwent tests for thyroid function and thyroid antibodies (thyroid peroxidase antibody and thyroglobulin autoantibody). We divided the patients suffering from euthyroidism and AIS into positive thyroid autoantibody and negative thyroid autoantibody groups. Demographic profiles, risk factors, and functional outcomes were compared between the two groups. Results. Out of the total 422 patients, 50 (11.8%) were included in the positive thyroid autoantibody group. The National Institutes of Health Stroke Scale (NIHSS) score at admission and discharge was higher in the positive thyroid autoantibody group than the negative thyroid autoantibody group ( $P<0.05$ ). In addition, there was significant difference in the mortality during hospitalizations between the two groups ( $P<0.01$ ). Conclusion. This study showed that thyroid autoantibodies aggravate stroke severity in euthyroidism with AIS. We speculate that vascular damage related to thyroid autoimmunity may aggravate the increased risk of unfavorable outcomes, independent of thyroid function.