Migraine comorbidity and cognitive performance in patients with focal epilepsy

Migraine - a borderland disease to epilepsy: near it but not of it

BACKGROUND

Migraine and epilepsy are two paroxysmal chronic neurological disorders affecting a high number of individuals and being responsible for a high individual and socioeconomic burden. The link between these disorders has been of interest for decades and innovations concerning diagnosing and treatment enable new insights into their relationship.

FINDINGS

Although appearing to be distinct at first glance, both diseases exhibit a noteworthy comorbidity, shared pathophysiological pathways, and significant overlaps in characteristics like clinical manifestation or prophylactic treatment. This review aims to explore the intricate relationship between these two conditions, shedding light on shared pathophysiological foundations, genetic interdependencies, common and distinct clinical features, clinically overlapping syndromes, and therapeutic similarities. There are several shared pathophysiological mechanisms, like CSD, the likely underlying cause of migraine aura, or neurotransmitters, mainly Glutamate and GABA, which represent important roles in triggering migraine attacks and seizures. The genetic interrelations between the two disorders can be observed by taking a closer look at the group of familial hemiplegic migraines, which are caused by mutations in genes like CACNA1A, ATP1A2, or SCN1A. The intricate relationship is further underlined by the high number of shared clinical features, which can be observed over the entire course of migraine attacks and epileptic seizures. While the variety of the clinical manifestation of an epileptic seizure is naturally higher than that of a migraine attack, a distinction can indeed be difficult in some cases, e.g. in occipital lobe epilepsy. Moreover, triggering factors like sleep deprivation or alcohol consumption play an important role in both diseases. In the period after the seizure or migraine attack, symptoms like speech difficulties, tiredness, and yawning occur. While the actual attack of the disease usually lasts for a limited time, research indicates that individuals suffering from migraine and/or epilepsy are highly affected in their daily life, especially regarding cognitive and social aspects, a burden that is even worsened using antiseizure medication. This medication allows us to reveal further connections, as certain antiepileptics are proven to have beneficial effects on the frequency and severity of migraine and have been used as a preventive drug for both diseases over many years.

CONCLUSION

Migraine and epilepsy show a high number of similarities in their mechanisms and clinical presentation. A deeper understanding of the intricate relationship will positively advance patient-oriented research and clinical work.

Association between migraine and epilepsy: a meta-analysis

Background

Epidemiological studies have demonstrated a comorbid association between migraine and epilepsy. However, despite the long history of this association, the exact nature of the relationship between migraine and epilepsy remains largely unresolved. Therefore, it is crucial to conduct a meta-analysis in order to thoroughly investigate the relationship between migraine and epilepsy.

Methods

Odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs) regarding association between migraine and epilepsy were summarized using STATA 12.0 software.

Results

There was an 80% increase in the lifetime prevalence of migraine among patients with epilepsy, compared to those without epilepsy with a random effects model (OR/RR: 1.80, 95% CI: 1.35 to 2.40, I2 = 97.5%, p < 0.001). There was an 80% increase in the lifetime prevalence of epilepsy among patients with migraine, compared to those without migraine with a random effects model (OR/RR: 1.80, 95% CI: 1.43 to 2.25, I2 = 80.6%, p < 0.001).

Conclusions

It is important to note the comorbid association between migraine and epilepsy examined in the study.

Diagnosis of comorbid migraine without aura in patients with idiopathic/genetic epilepsy based on the gray zone approach to the International Classification of Headache Disorders 3 criteria

Background

Migraine without aura (MwoA) is a very frequent and remarkable comorbidity in patients with idiopathic/genetic epilepsy (I/GE). Frequently in clinical practice, diagnosis of MwoA may be challenging despite the guidance of current diagnostic criteria of the International Classification of Headache Disorders 3 (ICHD-3). In this study, we aimed to disclose the diagnostic gaps in the diagnosis of comorbid MwoA, using a zone concept, in patients with I/GEs with headaches who were diagnosed by an experienced headache expert.

Methods

In this multicenter study including 809 consecutive patients with a diagnosis of I/GE with or without headache, 163 patients who were diagnosed by an experienced headache expert as having a comorbid MwoA were reevaluated. Eligible patients were divided into three subgroups, namely, full diagnosis, zone I, and zone II according to their status of fulfilling the ICHD-3 criteria. A Classification and Regression Tree (CART) analysis was performed to bring out the meaningful predictors when evaluating patients with I/GEs for MwoA comorbidity, using the variables that were significant in the univariate analysis.

Results

Longer headache duration (<4 h) followed by throbbing pain, higher visual analog scale (VAS) scores, increase of pain by physical activity, nausea/vomiting, and photophobia and/or phonophobia are the main distinguishing clinical characteristics of comorbid MwoA in patients with I/GE, for being classified in the full diagnosis group. Despite being not a part of the main ICHD-3 criteria, the presence of associated symptoms mainly osmophobia and also vertigo/dizziness had the distinguishing capability of being classified into zone subgroups. The most common epilepsy syndromes fulfilling full diagnosis criteria (n = 62) in the CART analysis were 48.39% Juvenile myoclonic epilepsy followed by 25.81% epilepsy with generalized tonic-clonic seizures alone.

Conclusion

Longer headache duration, throbbing pain, increase of pain by physical activity, photophobia and/or phonophobia, presence of vertigo/dizziness, osmophobia, and higher VAS scores are the main supportive associated factors when applying the ICHD-3 criteria for the comorbid MwoA diagnosis in patients with I/GEs. Evaluating these characteristics could be helpful to close the diagnostic gaps in everyday clinical practice and fasten the diagnostic process of comorbid MwoA in patients with I/GEs.

"Is this normal after such a major surgery?" Memory complaint after right temporal lobe excision in an adolescent

Memory deficits are commonly associated with temporal-lobe epilepsy. Memory may worsen after surgical resection of the temporal lobe. Risk factors for decline are structural integrity of the mesial temporal lobe structures and intact pre-operative memory. Subjective memory complaints are influenced by depression or other psychological disorders. A 16-year-old girl underwent resection from the right lateral and medial temporal lobe and after surgery she complained of a significant memory impairment, which was unexpected given her baseline assessment. Before undertaking a neuropsychological assessment, she was referred for a psychiatric consultation which revealed depression, leading to treatment with anditdepressant medication. Over time she also admitted to severe headaches and inadequate sleep. With these issues addressed, assessment indicated memory performance had not changed relative to her preoperative baseline with stability or improvement in memory across longitudinal assessments. This case illustrates the contribution of mood state and other potential factors in contributing to subjective memory complaints.

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.