Amygdalar metabolic activity associated with cerebrovascular events and carotid-vertebral artery stenosis in takayasu arteritis.

Abstract

To investigate the association of amygdalar activity with disease activity, inflammatory markers, cerebrovascular events, and structural vascular injury in patients with Takayasu arteritis (TAK). A total of 303 TAK patients underwent 18F-fluorodexoyglucose positron emission tomography/computed tomography (¹⁸F-PET/CT). Amygdalar, bone marrow, and vessel wall SUV were quantified. Clinical, laboratory, and imaging data were collected. The median follow-up duration was 27 months, during which adverse events were recorded. No significant association was found between amygdalar SUV and cerebrovascular events in the overall cohort. However, among treatment-naïve patients, those with cerebrovascular events had significantly lower amygdalar SUVmax (9.3±2.0 v.s. 10.3±2.0, p=0.011) and SUVmean (6.6±1.2 v.s. 7.4±1.5, p=0.003) than event-free patients. The low SUV group had a higher proportion of cerebrovascular events (24.3% vs. 15.9%, P=0.045), along with elevated IgG and IgA levels and decreased lymphocyte counts. Amygdalar SUVmax was an independent protective factor against combined carotid and vertebral artery stenosis (OR=0.876, P=0.032). During follow-up, the event group had significantly lower amygdalar SUVmax than the new-onset symptom group (8.2±2.6 v.s. 10.4±1.8, P=0.030). Low amygdalar metabolic activity in TAK is associated with adverse vascular outcomes and serves as an independent protective factor against combined carotid-vertebral artery stenosis, suggesting its potential as a novel imaging biomarker.