Abstract P565: Influence of Thyroid Disease on Presentation and Outcomes of Moyamoya Disease

Introduction: The presence of thyroid autoantibodies may play a role in the pathogenesis of moyamoya-type angiopathy. However, the influence of thyroid disease on presenting characteristics and treatment outcomes of moyamoya disease (MMD) remains unclear. Methods: Consecutive patients with MMD prospectively treated at our institution from 2015-2018 were reviewed. Results: 264 MMD patients with MMD were identified, 33 (12.5%) of whom presented with concurrent thyroid disease (4 hyperthyroid, 28 hypothyroid, 1 unspecified). Comparing groups with and without thyroid disease, there were no differences in age of presentation (p=0.12), racial composition (p=0.38), or rates of diabetes (p=0.32), hypertension (p=1.0), and hyperlipidemia (p=0.71). There was a higher proportion of females (94% F vs. 74% F, p=0.02) and lower rates of smoking (p=0.04) and alcohol consumption (p=0.04) in the thyroid disease group. Despite lower rates of vascular risk factors, the thyroid disease group exhibited more severe angiographic MMD at presentation, with higher Suzuki grade (p=0.002), higher proportion of bilateral disease (91% vs. 67%, p=0.007), and a trend towards more posterior circulation involvement (39% vs. 24%, p=0.09). MMD patients with concurrent thyroid disease were also more likely to present with carotid occlusion as opposed to large vessel stenosis (39% vs 10%, p=0.03), resulting in increased collateral filling via the extracranial (3.5% vs. 2.8%, p=0.04) and posterior circulations (24% vs. 16%, p=0.002). Patients with thyroid disease trended towards having higher rates of ischemic complications (28% vs. 16.8%, p=0.06) perioperatively; however, there were no differences in rates of post-operative hemorrhage (p=1.0) or transient neurologic events (p=0.85). Conclusions: Patients with concurrent moyamoya and thyroid disease present with more advanced angiographic intracranial disease, which may be associated with higher rates of ischemic complications in the perioperative period.