Cerebral hypercapnia-induced vasomotor reactivity in migraine with and without aura: a case-control study

Background: Dysfunction of the autonomic nervous system has long been a subject of considerable debate and a large number of studies have disclosed contradictory results. The aim of this study was to compare cerebral vasomotor reactivity in migraine with aura (MWA) patients with migraine without aura (MWO) ones. Methods: Ten MWA patients (7 females and 3 males; mean age: 39.70 years, SD: 12.03 years) and 10 age and sex-matched cases with MWO (P=0.303, P=1.000, respectively) underwent cerebral vasomotor reactivity (VMR) measurement using trans-cranial Doppler imaging of the middle cerebral artery (MCA). All patients were examined during an attack-free interval. Results: A statistically significant decrease in VMR value was seen in the migraine with aura group (2.8%, P=0.048); also systolic, diastolic and mean flow velocities were significantly greater in these patients (113.31, 59.13, 73.88, P=0.021, P=0.017 and P=0.049, respectively). Conclusion: Age-independent decrease in cerebral vasomotor reactivity in MWA as compared to MWO could support genetic involvement of brain autonomic control pathways in MWArather than MWO. Nitric oxide (NO) plays a major role, as a second messenger, in cerebral autonomic activity. Genetic involvement of its metabolic pathways may be a good explanation for observed dysfunction in MWA. Further molecular investigations could clarify this question.