Prevalence of migraine headache in an in-patient stroke population

Migraine and risk of atrial fibrillation: A 9-year follow-up based on the Trøndelag Health Study

BACKGROUND

Data from some population-based studies have indicated an increased risk of atrial fibrillation (AF) among patients with migraine, particularly among individuals with migraine with aura. The present study aimed to assess the association between primary headache disorders and AF.

METHODS

In a population-based 9-year follow-up design, we evaluated the questionnaire-based headache diagnosis, migraine and tension-type headache (TTH) included, collected in the Trøndelag Health Study (HUNT3) conducted in 2006-2008, and the subsequent risk of AF in the period until December 2015. The population at risk consisted of 39,340 individuals ≥20 years without AF at HUNT3 baseline who answered headache questionnaire during HUNT3. The prospective association was evaluated by multivariable Cox proportional hazard models with 95% confidence intervals (CIs).

RESULTS

Among the 39,340 participants, 1524 (3.8%) developed AF during the 9-year follow up, whereof 91% of these were ≥55 years. In the multivariable analyses, adjusting for known confounders, we did not find any association between migraine or TTH and risk of AF. The adjusted hazard ratios (HRs) were respectively 0.84 (95% CI = 0.64-1.11) for migraine, 1.16 (95% CI = 0.86-1.27) for TTH and 1.04 (95% CI = 0.86-1.27) for unclassified headache. However, in sensitivity analyses of individuals aged ≥55 years, a lower risk of AF was found for migraine (HR = 0.53; 95% CI = 0.39-0.73).

CONCLUSIONS

In this large population-based study, no increased risk of AF was found among individuals with migraine or TTH at baseline. Indeed, among individuals aged ≥55 years, migraine was associated with a lower risk for AF.

Migraine and atrial fibrillation: a systematic review

BACKGROUND AND PURPOSE

Patients with migraine are at increased risk of stroke. The aim was to systematically review the current literature on the association between migraine and atrial fibrillation, which is a relevant risk factor for stroke.

METHODS

PubMed was searched for 'migraine' AND 'atrial fibrillation' and selected original investigations on the association of migraine and atrial fibrillation for our analysis. Articles without original data, such as guidelines, narrative reviews, editorials and others, were excluded.

RESULTS

In all, 109 publications were found. Twenty-two were included and analysed for this review. The population-based Atherosclerosis Risk in Communities study showed a significant association of migraine with visual aura and incident atrial fibrillation (hazard ratio 1.30, 95% confidence interval 1.03-1.62, p = 0.02), but not for migraine without aura, compared to non-headache persons after multivariable adjustment for vascular risk factors. An even larger population-based study in Denmark confirmed this association (odds ratio 1.25, 95% confidence interval 1.16-1.36). Studies investigating patients with ischaemic stroke and migraine are methodologically insufficient and provide contradictory results. Ablation therapy for atrial fibrillation in patients with migraine might reduce migraine attacks, but transient post-ablation new-onset migraine-like headaches in persons without a history of migraine have also been reported.

CONCLUSION

Population-based studies indicate a significant association of migraine with aura and atrial fibrillation. In practical terms, screening for atrial fibrillation in patients who have a long history of migraine might be reasonable, whereas in patients with stroke or other disorders and migraine extensive screening for atrial fibrillation should be performed as in all patients without migraine.

The Migraine Aura

PURPOSE OF REVIEW

This article discusses the basic mechanisms of migraine aura and its clinical significance based upon evidence from human studies and animal models.

RECENT FINDINGS

Prospective clinical studies have reinforced the understanding that migraine aura is highly variable from one individual to the next as well as from attack to attack in an individual. While migraine with aura clearly has a higher heritability than migraine without aura, population studies have not identified specific genes that underlie this heritability for typical migraine with aura. Imaging studies reveal hypoperfusion associated with migraine aura, although the timing and distribution of this hypoperfusion is not strictly correlated with migraine symptoms. Mapping of migraine visual aura symptoms onto the visual cortex suggests that the mechanisms underlying the aura propagate in a linear fashion along gyri or sulci rather than as a concentric wave and also suggests that aura may propagate in the absence of clinical symptoms. Cortical spreading depression in animal models continues to be a translational model for migraine, and the study of spreading depolarizations in the injured human brain has provided new insight into potential mechanisms of cortical spreading depression in migraine. Migraine with aura has multiple comorbidities including patent foramen ovale, stroke, and psychiatric disorders; the shared mechanisms underlying these comorbidities remains a topic of active investigation.

SUMMARY

Although it occurs in the minority of patients with migraine, aura may have much to teach us about basic mechanisms of migraine. In addition, its occurrence may influence clinical management regarding comorbid conditions and acute and preventive therapy.

Migraine and Stroke: What's the Link? What to Do?

Migraine and stroke are common, disabling neurologic disorders, with a high socioeconomic burden. A link between them has been proposed years ago, and various theories have been proposed to explain this bidirectional relation. However, the precise causes remain unclear. We briefly summarize existing hypotheses of this correlation seeking for recommendations for stroke prevention in migraineurs, if any exist. Among the strongest suggested theories of migraine-stroke association are cortical spreading depression, endovascular dysfunction, vasoconstriction, neurogenic inflammation, hypercoagulability, increased prevalence of vascular risk factors, shared genetic defects, cervical artery dissection, and patent foramen ovale. There is no evidence that any preventive therapy in migraineurs should be used to decrease stroke risk, even in most predisposed subset of patients. However, a woman with migraine with aura should be encouraged to cease smoking and avoid taking oral contraceptives with high estrogen doses. We need further investigation to better understand the complexity of migraine-stroke association and to make firm recommendations for the future.

Peripheral Sensory Neurons Expressing Melanopsin Respond to Light

The ability of light to cause pain is paradoxical. The retina detects light but is devoid of nociceptors while the trigeminal sensory ganglia (TG) contain nociceptors but not photoreceptors. Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) are thought to mediate light-induced pain but recent evidence raises the possibility of an alternative light responsive pathway independent of the retina and optic nerve. Here, we show that melanopsin is expressed in both human and mouse TG neurons. In mice, they represent 3% of small TG neurons that are preferentially localized in the ophthalmic branch of the trigeminal nerve and are likely nociceptive C fibers and high-threshold mechanoreceptor Aδ fibers based on a strong size-function association. These isolated neurons respond to blue light stimuli with a delayed onset and sustained firing, similar to the melanopsin-dependent intrinsic photosensitivity observed in ipRGCs. Mice with severe bilateral optic nerve crush exhibit no light-induced responses including behavioral light aversion until treated with nitroglycerin, an inducer of migraine in people and migraine-like symptoms in mice. With nitroglycerin, these same mice with optic nerve crush exhibit significant light aversion. Furthermore, this retained light aversion remains dependent on melanopsin-expressing neurons. Our results demonstrate a novel light-responsive neural function independent of the optic nerve that may originate in the peripheral nervous system to provide the first direct mechanism for an alternative light detection pathway that influences motivated behavior.

Is the search for right-to-left shunt still worthwhile?

OBJECTIVES

Patent foramen ovale (PFO) is a common disembryogenic defect with well-attested prevalence but dubious etiopathogenetic linkage with cryptogenic stroke and different clinical conditions. Transcranial color-coded Doppler (TCCD) assures high accuracy in diagnosing right-to-left shunt (RLS) and its functional aspects. Aim of the study was to evaluate RLS prevalence and degree in subjects submitted to TCCD for conditions theoretically associated or caused by paradoxical embolism to the brain.

METHODS

PFO assessment, performed in 10 major diagnostic categories and a control group, followed a standardized protocol with a 10 or 20 microbubbles (MB) cutoff to identify any or only large RLS, respectively.

RESULTS

Among 2113 patients, a significant larger RLS prevalence was found in stroke (53.3%), TIA (45.7%) and migraine with aura (39.7%) when compared with non-migraineurs controls (25.5%). RLS degree was significantly higher in stroke and TIA patients: The ROC curve from MB load data helped to identify new cutoff values for both normal breathing (42 MB) and Valsalva (139 MB) tests. From logistic regression, a family history for PFO, ASA, and male gender appeared independent predictors of a RLS. By contrast, RLS seemed independent of white matter abnormalities presence on brain neuroimaging or stroke mimics.

CONCLUSIONS

In addition to recently defined criteria, genetically determined inheritable traits and epidemiologic characteristics (male gender) should be taken into account when assessing PFO and related cerebrovascular risk profile. A newly defined threshold in TCCD MB count is suggested to discriminate shunts related to stroke and TIA from innocent ones.

Migraine aura: new ideas about cause, classification, and clinical significance

PURPOSE OF REVIEW

The migraine aura is a dramatic spontaneous change in brain activity resulting in a variety of transient neurological symptoms. The purpose of this review is to address recent advances in the understanding of aura and its role in migraine.

RECENT FINDINGS

The formal classification of migraine aura is becoming both broader and more detailed. Traditionally viewed as a primary event that triggers a migraine attack, studies regarding the timing of aura relative to other symptoms of migraine indicate that it may not in fact play a primary role in initiating an attack. Careful recording and analysis of visual aura symptoms provides new insight into the initiation and propagation of the underlying brain phenomenon, and the different regions of visual cortex that produce different visual perceptions. Migraine with aura may have different responses to acute and preventive therapies.

SUMMARY

There has been significant evolution of concepts regarding the causes of migraine aura, how it is best defined, and how it fits into the picture of the migraine disorder as a whole. Regardless of its exact role in the genesis of migraine, an increased understanding of aura has the potential to provide important new insight into not only migraine but also fundamental mechanisms of brain physiology.

A meta-analysis of case-control studies of the association of migraine and patent foramen ovale

OBJECTIVES

To establish quantitative evidence, we performed the first meta-analysis of case-control studies assessing the relationship between migraine and patent foramen ovale (PFO).

METHODS

MEDLINE and EMBASE were searched through April 2015 using PubMed and OVID. Eligible studies were case-control studies reporting PFO (or migraine) prevalence in migraine patients versus no-migraine subjects (or PFO patients versus no-PFO subjects).

RESULTS

Of 395 potentially relevant articles screened initially, 21 eligible studies enrolling a total of 5572 participants were identified and included. Pooled analyses demonstrated statistically significant 3.36-fold migraine-with-aura [odds ratio (OR), 3.36; 95% confidence interval (CI), 2.04-5.55; p<0.00001] and 2.46-fold migraine-with/without-aura prevalence (OR, 2.46; 95% CI, 1.55-3.91; p=0.0001) but statistically non-significant 1.30-fold migraine-without-aura prevalence (OR, 1.30; 95% CI, 0.85-1.99; p=0.22) in PFO patients relative to no-PFO subjects.

CONCLUSIONS

PFO is associated with 3.4-fold migraine-with-aura and 2.5-fold migraine-with/without-aura prevalence but unassociated with migraine-without-aura prevalence.