Autonomic asymmetry in migraine: augmented parasympathetic activation in left unilateral migraineurs

Abstract

Brain autonomic control is asymmetrical, the left hemisphere affecting predominantly parasympathetic function and the right hemisphere affecting predominantly sympathetic function. It is not known whether the extent of autonomic activation is altered in migraine, although the fact that some migraineurs express parasympathetic features such as facial flushing, lacrimation and rhinorrhoea might suggest increased parasympathetic activation. We instilled diluted soapy eyedrops and measured (i) the trigemino-parasympathetic reflex by the vasodilator response of forehead skin bilaterally using photoplethysmography; (ii) the somato-sympathetic reflex by vasoconstriction in the index finger; and (iii) heart rate response. We studied 14 left-sided and 15 right-sided unilateral migraineurs outside attacks. We found that left-side migraineurs had significantly higher bilateral parasympathetic vasodilatation, regardless of the stimulation or measurement side (+60.1 +/- 6.4%) compared with right-side migraineurs (+41.9 +/- 6.4%, P < 0.05). Sympathetic vasoconstriction, however, was similar for the two groups (left, -15.9 +/- 4.2%; right, -17.7 +/- 4.1%, NS). Bradycardia was significantly more pronounced for the left-side migraineurs (interbeat, RR interval increase of +6.2 +/- 1.1% versus +3.1 +/- 1.1%, P < 0.04). We conclude that unilateral left-side migraineurs have increased parasympathetic activation in response to pain compared with right-side migraineurs. Sympathetic responses were similar in the two groups and seemed not to be affected by migraine side. Since cranial parasympathetic activity induces cerebral vasodilatation, this augmentation might be an inherent part of the migraine pathophysiology in these patients.

Errors in Recognition and Management are Still Frequent in Patients with Cluster Headache

“…The very different temporal patterns and duration of attacks in migraine and CH are key factors on distinguishing between these two conditions, as it is true that other features of these headaches can overlap. These overlapping features include the development of aura (known to occur in up to 20% of CH cases) [14], the pain intensity (2/3 of migraine patients also have severe pain), the existence of cranial autonomic symptoms (at least one of these symptoms is known to occur in about half of migraine patients) [15,16,17,18,19,20,21,22] or the presence of associated ‘migraine' features in CH attacks (in a large German cohort CH attacks associated photo/phonofobia in 61% and nausea and vomiting in 28% of cases) [13]. The IHS criteria of ‘strictly unilateral pain' may also cause confusion as switching attack sides has been reported in at least 10% of CH cases [23] and also in up to 10% of cases migraine attacks are strictly unilateral for years [24].…”

Sphenopalatine ganglion neuromodulation in migraine: What is the rationale?

“…Though an alleged autonomic dysfunction has been dealt with widely, migraine pathophysiology is complex, and results have advocated both hypo-and hyperfunction of the sympathetic and parasympathetic systems (Table 2) (46)(47)(48)(49)(50)(51)(52)(53)(54).…”

Gastric Stasis in Migraine: More Than Just a Paroxysmal Abnormality During a Migraine Attack

“…20 Several clinical observations have found autonomic abnormalities in migraineurs compared to normal controls. [21][22][23][24] Periaqueductal gray (PAG) has been demonstrated to be dysfunctional in migraine. MRI imaging has determined that iron accumulation occurs in the PAG and that these changes correlate with duration of migraine frequency, are not independent of the presence of aura, and do not correlate with patient age.…”