Characteristics and outcomes of subarachnoid hemorrhage from vertebral artery dissection: A comparative study with other non-traumatic etiologies

Aim: Vertebral artery dissection (VAD) is a rare cause of non-traumatic subarachnoid hemorrhage (SAH) with significant clinical implications. This study compared the clinical characteristics and outcomes of SAH from intracranial VAD rupture to those from other etiologies, primarily aneurysmal rupture.
Methods: This single-center retrospective cohort study at Okayama University Hospital included patients with non-traumatic SAH diagnosed between 2019 and 2023. Patients were categorized into "VAD rupture" and "other etiologies" groups. The main outcome was clinical presentation and symptoms. Additional outcomes included ICU mortality, in-hospital mortality, and unfavorable outcomes at discharge and 6 months, defined as a modified Rankin Scale score of 3-6.
Results: A total of 66 patients were included, with 14 in the VAD rupture group and 52 in the other etiologies group. The VAD rupture group was younger (median age 49 vs. 64 years, p = 0.003) and had a higher incidence of out-of-hospital cardiac arrest (42.9% vs. 9.6%, p = 0.011). Preceding headache was more common in the VAD rupture group (78.6% vs. 11.5%, p < 0.001), with a median duration of 36 h before presentation. ICU and in-hospital mortality was higher in the VAD rupture group (both 50.0% vs. 19.3%, p = 0.019). No significant differences were found in unfavorable neurological outcomes at hospital discharge and 6 months.
Conclusions: VAD-related SAH often presents with prodromal headaches, severe symptoms like out-of-hospital cardiac arrest, and higher ICU and in-hospital mortality than other SAH causes, though long-term outcomes are similar. Larger, prospective studies are needed to refine interventions.