Cerebrovascular Reactivity to Hypercapnia in Patients with Migraine: A Dual-Echo Arterial Spin Labeling MRI Study

Objective: This study aimed to compare cerebrovascular reactivity between patients with migraine and controls using state-of-the-art magnetic resonance imaging (MRI) techniques. Background: Migraine is associated with an increased risk of cerebrovascular disease, but the underlying mechanisms are still not fully understood. Impaired cerebrovascular reactivity has been proposed as a link. Previous studies have evaluated cerebrovascular reactivity with different methodologies and results are conflicting. Methods: In this single-center, observational, case-control study, we included 31 interictal patients with migraine without aura (aged 19-66 years, 17 females) and 31 controls (aged 22-64 years, 18 females) with no history of vascular disease. Global and regional cerebrovascular reactivities were assessed with a dual-echo arterial spin labeling (ASL) 3.0 T MRI scan of the brain which measured the change in cerebral blood flow (CBF) and BOLD (blood oxygen level dependent) signal to inhalation of 5% carbon dioxide. Results: When comparing patients with migraine to controls, cerebrovascular reactivity values were similar between the groups, including mean gray matter CBF-based cerebrovascular reactivity (3.2 +/- 0.9 vs 3.4 +/- 1% Delta CBF/mmHg CO2; p = 0.527), mean gray matter BOLD-based cerebrovascular reactivity (0.18 +/- 0.04 vs 0.18 +/- 0.04% Delta BOLD/mmHg CO2; p = 0.587), and mean white matter BOLD-based cerebrovascular reactivity (0.08 +/- 0.03 vs 0.08 +/- 0.02% Delta BOLD/mmHg CO2; p = 0.621).There was no association of cerebrovascular reactivity with monthly migraine days or migraine disease duration (all analyses p > 0.05). Conclusion: Cerebrovascular reactivity to carbon dioxide seems to be preserved in patients with migraine without aura.