Clinical characteristics of patients with comorbidity of migraine and epilepsy

Cortical pain induced by optogenetic cortical spreading depression: from whole brain activity mapping

BACKGROUND

Cortical spreading depression (CSD) is an electrophysiological event underlying migraine aura. Traditional CSD models are invasive and often cause injuries. The aim of the study was to establish a minimally invasive optogenetic CSD model and identify the active networks after CSD using whole-brain activity mapping.

METHODS

CSD was induced in mice by light illumination, and their periorbital thresholds and behaviours in the open field, elevated plus-maze and light-aversion were recorded. Using c-fos, we mapped the brain activity after CSD. The whole brain was imaged, reconstructed and analyzed using the Volumetric Imaging with Synchronized on-the-fly-scan and Readout technique. To ensure the accuracy of the results, the immunofluorescence staining method was used to verify the imaging results.

RESULTS

The optogenetic CSD model showed significantly decreased periorbital thresholds, increased facial grooming and freezing behaviours and prominent light-aversion behaviours. Brain activity mapping revealed that the somatosensory, primary sensory, olfactory, basal ganglia and default mode networks were activated. However, the thalamus and trigeminal nucleus caudalis were not activated.

CONCLUSIONS

Optogenetic CSD model could mimic the behaviours of headache and photophobia. Moreover, the optogenetic CSD could activate multiple sensory cortical regions without the thalamus or trigeminal nucleus caudalis to induce cortical pain.

Headache in people with epilepsy

Epidemiological estimates indicate that individuals with epilepsy are more likely to experience headaches, including migraine, than individuals without epilepsy. Headaches can be temporally unrelated to seizures, or can occur before, during or after an episode; seizures and migraine attacks are mostly not temporally linked. The pathophysiological links between headaches (including migraine) and epilepsy are complex and have not yet been fully elucidated. Correct diagnoses and appropriate treatment of headaches in individuals with epilepsy is essential, as headaches can contribute substantially to disease burden. Here, we review the insights that have been made into the associations between headache and epilepsy over the past 5 years, including information on the pathophysiological mechanisms and genetic variants that link the two disorders. We also discuss the current best practice for the management of headaches co-occurring with epilepsy and highlight future challenges for this area of research.

Treatment of migraine attacks and prevention of migraine: Guidelines by the German Migraine and Headache Society and the German Society of Neurology

In collaboration with some of the leading headache centres in Germany, Switzerland and Austria, we have established new guidelines for the treatment of migraine attacks and the prevention of migraine. A thorough literature research of the last 10 years has been the basis of the current recommendations. At the beginning, we present therapeutic novelties, followed by a summary of all recommendations. After an introduction, we cover topics like drug therapy and practical experience, non-effective medication, migraine prevention, interventional methods, non-medicational and psychological methods for prevention and therapies without proof of efficacy.

Pediatric Epilepsy Surgery: The Prognostic Value of Central Nervous System Comorbidities in Patients and their Families

Central nervous system comorbidities have been identified in patients with epilepsy. Several of these comorbidities have been correlated with poor surgery outcomes in patient cohorts. The authors sought to determine if prevalence of comorbidities in pediatric epilepsy surgery patients and their families correlate with long-term seizure outcome in a cross-sectional analysis. Three-generation pedigrees were elicited to compare family history of epilepsy, ADHD, anxiety, autism, bipolar disorder, cognitive disability, depression, migraine, and motor disability to surgery outcomes in 52 patients. Proportions of affected patients and relatives were compared to general population comorbidity rates and the patients' most recent seizure outcome classification. Patients and families had significantly higher rates of comorbidities than the general population. Poorer long-term seizure outcomes following resective surgery were associated with autism or cognitive disability in patients. Together these data support evidence for a common pathophysiological mechanism between epilepsy and central nervous system comorbidities.

Comorbidity between headache and epilepsy in a Chinese epileptic center

Here we investigated the characteristics and prevalence of headaches in patients with epilepsy in a Chinese epileptic center based on the International Classification of Headache Disorders, 2nd edition. We found that 60.14% (667/1109) of patients reported headaches. Headache was less prevalent in males (57.17%) than in females (63.75%). Interictal headaches were present in 34.62% of patients, and 139/1109 (12.53%) patients had interictal migraine, which was a higher percentage than reported in a large population-based study from the same area (9.3%) using the same screening question. In addition, 469 (70.31%) patients had postictal headache, migraine characteristics were present in 73.35% of these patients, and 15.35% also suffered from interictal migraine. Lastly, 8.85% patients had preictal headache. These results confirm that headache is very common in patients with epilepsy. Seizures often trigger postictal headaches with migraine features. The comorbidity of migraines and epilepsy should receive clinical attention, as it may influence antiepileptic drug choice, and the headache may require specific treatment.

Headache and comorbidity in children and adolescents

Headache is one of the most common neurological symptom reported in childhood and adolescence, leading to high levels of school absences and being associated with several comorbid conditions, particularly in neurological, psychiatric and cardiovascular systems. Neurological and psychiatric disorders, that are associated with migraine, are mainly depression, anxiety disorders, epilepsy and sleep disorders, ADHD and Tourette syndrome. It also has been shown an association with atopic disease and cardiovascular disease, especially ischemic stroke and patent foramen ovale (PFO).

Primary headache and epilepsy: a multicenter cross-sectional study

The prevalence and characteristics of interictal headache, epilepsy and headache/epilepsy comorbidity were assessed in 858 women and 309 men aged 18-81 years from headache and epilepsy centers in Italy. The research hypothesis was that comorbidity among patients with either disorder would be expected to be higher than in the general population. Interictal headache was diagnosed in 675 cases (migraine 482; tension-type headache 168; other types 25), epilepsy in 336 (partial 171; generalized 165) and comorbidity in 156 (1.6% from headache centers; 30.0% from epilepsy centers). Patients with epilepsy, headache and comorbidity differed in a number of demographic and clinical aspects. However, for both headache and epilepsy, a family history of the same clinical condition was equally prevalent in patients with and without comorbidity. These findings do not support the purported association between headache and epilepsy.

Links between headaches and epilepsy: current knowledge and terminology

INTRODUCTION AND OBJECTIVES

Headaches (including migraines) and epilepsy have a high level of comorbidity and may be confused during diagnosis. Although physicians have known for centuries that these two conditions are somehow linked, their relationship remains poorly understood. Herein we describe the known associations between them, their underlying physiopathologic and genetic mechanisms, and the treatments recommended for them.

METHOD

We have reviewed the most relevant publication of headache/migraine and epilepsy by using the PubMed data base.

DESCRIPTION

An individual can suffer both from headaches (either migraine and/or other type of headache) and epilepsy, either by chance or because of a common underlying pathology. In these cases, the headache usually occurs at a different moment than the seizure ("interictal headache"). However, headaches sometimes occur simultaneously with, or very close in time to, the seizure: one that occurs at the same time as an epileptic seizure is known as an "ictal epileptic headache" or as "hemicrania epileptica"; one that precedes a seizure is known as a "pre-ictal headache"; and one that follows a seizure is known as a "post-ictal headache". There is a particular type of pre-ictal headache, known as "migralepsy", which occurs during or just after a migraine aura.

CONCLUSIONS

The terminology and concepts employed to describe possible associations between headaches (mainly migraines) and epilepsy have evolved over time with increasing clinical and physiopathogenic knowledge. Some researchers have suggested eliminating the term migralepsy and using the terms ictal epileptic headache and hemicrania epileptica exclusively and uniformly in all classification systems.

Multi-center study on migraine and seizure-related headache in patients with epilepsy

PURPOSE

The purpose of this study is to investigate the frequency and characteristics of migraine and seizure-related headache (SRH) according to the criteria of the International Headache Society.

MATERIALS AND METHODS

A questionnaire was undertaken at the initial evaluation of newly referred patients from 32 epilepsy clinics.

RESULTS

Of a total of 597 patients, 74 (12.4%) patients had migraine. Age at the onset of epilepsy was lower in patients with migraine than in those without. Twenty-six (4.4%), nine (1.5%), and 146 (24.5%) patients experienced prodromal, ictal, and postictal SRH, respectively (n = 169, 28.3%). A pain intensity of prodromal and postictal SRH was 6.1 +/- 1.5 (SD) and 6.3 +/- 1.9 (SD) on the visual analogue scale, and their duration was 12.6 +/- 26.7 (SD) hours and 9.0 +/- 17.4 (SD) hours, respectively. Age at the onset of epilepsy was lower in patients with SRH than in those without, and the risk of occurrence of SRH was significantly greater in patients with longer epilepsy duration. SRH could be classified as a type of migraine in 46.2% of patients with prodromal SRH and in 36.3% of patients with postictal SRH. Prodromal SRH occurred more frequently and was more likely to be a migraine-type in patients with migraine compared with those without. Postictal SRH occurred more frequently and was more likely to be a migraine-type in patients with migraine.

CONCLUSION

This study suggests that SRH is a frequent accompanying symptom of epileptic seizures causing major impairment in daily life, and migraine is an important comorbidity of epilepsy, affecting the incidence and characteristics of SRH.

Comorbidity between headache and epilepsy in a pediatric headache center

The purpose of this study was to analyse the comorbidity between headache and epilepsy in a large series of children with headache (1,795). Fifty-six cases (3.1%) suffered from idiopathic headache and idiopathic or cryptogenic epilepsy or unprovoked seizures. There was a strong association between migraine and epilepsy: in migraineurs (46/56) the risk of epilepsy was 3.2 times higher when compared with tension-type headache, without significant difference between migraine with and without aura (P = 0.89); children with epilepsy had a 4.5-fold increased risk of developing migraine than tension-type headache. In cases with comorbidity, focal epilepsies prevailed (43/56, 76.8%). Migraineurs affected by focal epilepsies (36/56) had a three times higher risk of having a cryptogenic epilepsy (27/36, 75%) than an idiopathic epilepsy (9/36, 25%) (P = 0.003). In migraine with aura, epilepsy preceded migraine in 71% of cases. Photosensitivity (7/56, 12.5%) and positive family history for epilepsy (22/56, 39%) were frequent in cases with comorbidity.

Neuro-Ophthalmologic Manifestations of Epilepsy

This review summarizes the major neuro-ophthalmologic manifestations of epilepsy. Positive or negative visual manifestations such as hallucinations or visual loss may be seen. There is considerable overlap of the visual manifestations with migrainous aura and transient ischemic attack (TIA), making a detailed history important for accurate diagnosis. Oculomotor manifestations, such as tonic eye deviation, are often recognized to have localizing value. Nystagmus or repetitive blinking may be present and offer clues in clinically subtle seizures.

Serotonin: modulator of a drive to withdraw

Serotonin is a fundamental neuromodulator in both vertebrate and invertebrate nervous systems, with a suspected role in many human mental disorders. Yet, because of the complexity of serotonergic function, researchers have been unable to agree on a general theory. One function suggested for serotonin systems is the avoidance of threat. We propose and review evidence for an alternative hypothesis, that a phylogenetically primitive of function of serotonin is to oppose the activating neuromodulators (particularly noradrenalin and dopamine). The functional effect of this opposition can be seen as applying a drive to withdraw from dangerous, aversive or high stimulation environments. Proposing that serotonin is involved in a drive to withdraw and seek contentment, instead of a drive to avoid, may be compatible with several lines of evidence on serotonin function and may facilitate a better understanding of serotonergic neuromodulation in human psychopathology.

Migraine-associated risks and comorbidity

This review reports important co-morbid conditions of migraine and resulting consequences for the choice of acute and preventive treatments of migraine. Comorbidity in this context means the occurrence of two diseases in an individual beyond chance. The basis of comorbidity can be genetic and/or based on common environmental factors. In some cases, the temporal relationship is unclear and one disease can cause another disease. In order to prove a real comorbidity, large-scale and well-performed epidemiological studies are required.

Headaches add to the burden of epilepsy

The objective was to investigate and classify headaches in 109 consecutive adult patients with epilepsy. A semi-structured interview was performed in those who confirmed such symptoms (65%). Interictal headaches were present in 52%; 20% had interictal migraine. Postictal headache was reported in 44%. Migraine characteristics were present in 42% of these, and most of them (74%) also suffered from interictal migraine. Six percent had preictal headache. In partial epilepsy, there was an association between headache lateralisation and interictal EEG abnormalities (p=0.02). We conclude that headache, including migraine, is very common in patients with epilepsy. Unilateral headache may represent a lateralising sign in focal epilepsy. Seizures often trigger postictal headaches with migraine features, which often are associated with interictal migraine. Migrainous headaches sometimes proceed into epileptic seizures. The comorbidity of migraine and epilepsy should receive ample clinical attention, as it may influence antiepileptic drug choice, and the headache may need specific treatment.

Anatomical alterations of the visual motion processing network in migraine with and without aura

BACKGROUND

Patients suffering from migraine with aura (MWA) and migraine without aura (MWoA) show abnormalities in visual motion perception during and between attacks. Whether this represents the consequences of structural changes in motion-processing networks in migraineurs is unknown. Moreover, the diagnosis of migraine relies on patient's history, and finding differences in the brain of migraineurs might help to contribute to basic research aimed at better understanding the pathophysiology of migraine.

METHODS AND FINDINGS

To investigate a common potential anatomical basis for these disturbances, we used high-resolution cortical thickness measurement and diffusion tensor imaging (DTI) to examine the motion-processing network in 24 migraine patients (12 with MWA and 12 MWoA) and 15 age-matched healthy controls (HCs). We found increased cortical thickness of motion-processing visual areas MT+ and V3A in migraineurs compared to HCs. Cortical thickness increases were accompanied by abnormalities of the subjacent white matter. In addition, DTI revealed that migraineurs have alterations in superior colliculus and the lateral geniculate nucleus, which are also involved in visual processing.

CONCLUSIONS

A structural abnormality in the network of motion-processing areas could account for, or be the result of, the cortical hyperexcitability observed in migraineurs. The finding in patients with both MWA and MWoA of thickness abnormalities in area V3A, previously described as a source in spreading changes involved in visual aura, raises the question as to whether a "silent" cortical spreading depression develops as well in MWoA. In addition, these experimental data may provide clinicians and researchers with a noninvasively acquirable migraine biomarker.

Relationship between migraine and epilepsy in pediatric age

OBJECTIVE

Many studies have supported the hypothesis of alteration of cortical hyperexcitability as a possible pathological mechanism underlying the onset of migraine and epileptic attacks. Different biochemical pathways involving cellular structures may increase or decrease the excitability of neuronal membranes. The aim of this study was to identify a possible link between migraine and epilepsy from a clinical and neurophysiologic point of view.

METHODS

One-hundred thirty-seven children and adolescents consecutively diagnosed for tension-type headache and idiopathic migraine with and without aura were studied. Anamnestic, clinical, and instrumental data were collected by a neurological examination, a specific questionnaire, and awake electroencephalogram (EEG) registrations. EEG features of nonheadache and nonseizures control group were compared.

RESULTS

Fourteen cases (10.2%) had a positive history for seizures with fever, isolated seizures, or epilepsy. Distribution differed according to headache diagnosis; migraine with aura (MWA) was largely prevalent. Specific electroencephalographic abnormalities were present in 11.7% of the sample, with a significant different distribution across the groups of children with headache and the control group: specific interictal abnormalities were found in 10 of 23 (43.5%) children with MWA. Two factors, seizures and specific interictal electroencephalographic abnormalities, showed a different distribution in patients with MWA compared to other classes of headache and control group (P < or = .01).

CONCLUSION

The present study supports the hypothesis of a possible clinical continuum between some types of MWA and epileptic syndromes as entities due to altered neuronal excitability with similar genetic substrates.

Effect of cortical spreading depression on synaptic transmission of rat hippocampal tissues

Cortical spreading depression (CSD) is believed to be a putative neuronal mechanism underlying migraine aura and subsequent pain. In vitro and ex vivo/in vitro brain slice techniques were used to investigate CSD effects on the field excitatory postsynaptic potentials (fEPSP) and tetanus-induced long-term potentiation (LTP) in combined rat hippocampus-cortex slices. Induction of CSD in combined hippocampus-cortex slices in which DC negative deflections did not propagate from neocortex to hippocampus significantly augmented fEPSP amplitude and LTP in the hippocampus. Propagation of CSD to the hippocampus resulted in a transient suppression followed by reinstatement of fEPSP with amplitude of pre-CSD levels. LTP was inhibited when DC potential shifts were recorded in the hippocampus. Furthermore, CSD was induced in anaesthetized rats and, thereafter, hippocampal tissues were examined in vitro. LTP was significantly enhanced in hippocampal slices obtained from ipsilateral site to the hemisphere in which CSD was evoked. The results indicate the disturbances of hippocampal synaptic transmission triggered by propagation of CSD. This perturbation of hippocampal synaptic transmission induced by CSD may relate to some symptoms occurring during migraine attacks, such as amnesia and hyperactivity.

Epilepsy and migraine: The dopamine hypotheses

Migraine and epilepsy are both chronic recurrent disorders with paroxysmal attacks. They also share some similar risk factors, symptoms, and preventive medications. Dopamine has long been postulated to be involved in the pathophysiology of migraine and epileptogenesis, by many supporting evidences. However, the role of dopamine is still controversial till now. A lack of a comprehensive hypothetical model may be one of the reasons. "Dopamine hypothesis" is not a new term, but it is proposed to explain the pathophysiology and the associated phenomena of these disorders. The hypotheses suggest that, in migraine, there is a low dopamine tone, while there is a high state of dopamine in generalized epilepsy. But the periodic attacks of headaches and seizures maybe both due to a fall in dopamine activity. Dopamine therefore plays a key role in the linkage of neuroendocrine, autonomic system and neuronal activity. Dopamine agonist is also implied in prophylaxis and neuroprotection in both disorders.

Brain Hyperexcitability: The Basis for Antiepileptic Drugs in Migraine Prevention

Abnormal brain excitability may provide the susceptibility for triggering migraine attacks. Antiepileptic drugs may diminish neuronal excitability and consequently reduce the frequency of migraine. Because migraine aura is predominantly visual, hyperexcitability of the occipital cortex has been the focus of investigations. Functional magnetic resonance imaging of the brain and magnetoencephalography provide the most consistent evidence for the role of brain hyperexcitability in migraine and confirm that triggering an abnormal electric and metabolic event consistent with the cortical spreading depression (CSD) of Leao is anatomically and functionally linked with migraine aura symptoms. Future drug discovery should focus on the interface between the excitable cell and the earliest events of CSD.

Topiramate monotherapy in epilepsy and migraineprevention

OBJECTIVES

The purposes of this review were to assess the efficacy of topiramate as monotherapy for epilepsy and migraine prevention, describe how it should be used, and give clinical advice on how to manage the practical aspects of dosing, titration, and possible adverse events in these 2 indications.

METHODS

We searched the PubMed and BIOSIS databases using the key words topiramate, epilepsy, and migraine from the year 1987 onward, and subsequently focused the search on larger controlled trial studies of topiramate as monotherapy.

RESULTS

Studies have evaluated the use of topiramate as monotherapy in the treatment of partial-onset and generalized seizures and in the prevention of migraine. In a randomized study, 75% of epilepsy patients treated with 400 mg/d topiramate remained seizure free at 1 year. Patients in the same study treated with a lower dose of topiramate (50 mg/d) also experienced notable seizure reductions, with 59% of patients free of seizures at 1 year. A comparison trial of topiramate (100 or 200 mg/d), valproate, and carbamazepine found that topiramate was associated with a similar time to first posttreatment seizure as the other 2 agents (P = NS). Trials of topiramate monotherapy in migraine prevention found that 100 mg/d was associated with a > or =50% reduction in monthly migraine frequency in 49% to 54% of patients. The migraine prevention trials typically used a starting dose of 25 mg/d, with weekly increases of 25 mg and an initial monotherapy target dose of 100 mg/d. The most common adverse events associated with topiramate are paresthesia, weight loss, and other centrally mediated symptoms, many of which may be ameliorated by proper titration and dosing and by good communication between physician and patient.

CONCLUSIONS

Data from controlled trials suggest that 100 mg/d topiramate as monotherapy is effective in the treatment of partial-onset and generalized seizures and in the prevention of migraine.