Aspirin or anticoagulation after cryptogenic stroke with patent foramen ovale: systematic review and meta-analysis of randomized controlled trials.

INTRODUCTION: Since closure has restrictive eligibility criteria, the vast majority of patients with cryptogenic stroke and patent foramen ovale (PFO) receive medical treatment. However, the optimal antithrombotic strategy is still unclear. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to define risk/benefit profile of anticoagulation compared with antiplatelet treatment in PFO-related stroke. METHODS: Systematic review protocol was registered in PROSPERO (CRD42019117559). Following PRISMA guidelines, we searched MEDLINE, EMBASE, and Cochrane CENTRAL database (2000-2019) for RCTs randomly allocating patients with cryptogenic stroke and PFO to medical treatment. Risk of bias was assessed with Cochrane RoB tool. Main outcomes were stroke recurrence and major bleeding. RoPE score-dependent analysis was implemented to define a possible role for patient selection. RESULTS: Five RCTs met inclusion criteria (3 high-, 1 fair-, 1 poor-quality RCTs). Overall, meta-analysis included 1565 patients (mean age 55.5 years), 753 (48.1%) receiving anticoagulation. Compared with antiplatelet treatment, anticoagulation conveyed no net benefit in prevention of recurrent stroke (OR = 0.66, 95% CI 0.41-1.07, pheterogeneity = 0.46), and associated with a non-significant higher risk of major bleeding (OR = 1.64, 95% CI 0.79-3.43, pheterogeneity = 0.57). In patients with high RoPE score, anticoagulation significantly reduced the risk of recurrent stroke (OR = 0.22, 95% CI 0.06-0.8, pheterogeneity = 0.88). CONCLUSION: Our meta-analysis shows that anticoagulation confers no net benefit in recurrent stroke prevention over antiplatelets in patients with PFO-related stroke. RoPE score might help in selecting patients benefiting from anticoagulation, but further trials are needed to delineate risk/benefit profile of anticoagulation.

HDAC3 role in medication consumption in medication overuse headache patients: a pilot study.

BACKGROUND: Medication overuse headache (MOH) is a common and debilitating disorder characterized by generation, perpetuation, and persistence of intense chronic migraine, caused by overuse of analgesics, triptans, or other acute headache compounds. It has been suggested that MOH could share some pathogenetic mechanisms with other kinds of drug addiction. In this regard, histone deacetylases 3 (HDAC3) seems to have a role in the memory processes involved in extinction of drug-seeking behavior in animal models. HDAC3 is inhibited by sodium valproate, a drug with proven efficacy in MOH. Recent evidence suggests an involvement of genetic factors in predisposition to medication overuse. RESULTS: In this association study, we sequenced all exons, intron/exon junctions, and 3'-5'UTR regions of HDAC3 in 23 MOH patients to investigate its role in medication overuse. Associations between genotypes with continuous and dichotomous clinical characteristics were tested by multivariate analysis and Fisher's exact test, respectively. Sequencing of HDAC3 revealed six single-nucleotide polymorphisms. The G allele of rs2530223 was significantly associated with the number of acute medications/month used and with the number of days/month in which medications were used (p = 0.006 and p = 0.007, respectively), but neither with headache frequency or intensity. None of the single-nucleotide polymorphisms (SNPs) was associated with clinical characteristics or response to sodium valproate. CONCLUSIONS: HDAC3 could be implicated in excessive medication consumption in MOH patients. Our preliminary findings provide support for the need of further investigation on larger independent samples to confirm and extend the role of HDAC3 in medication overuse headache.

Migraine-specific quality of life questionnaire and relapse of medication overuse headache.

BACKGROUND: The management of Medication overuse headache (MOH) represents a difficult challenge for clinicians and headache experts, particularly for the responder rate after a successful withdrawal treatment. The purpose of this study was to investigate the role of demographic and clinical characteristics as well as the score of Migraine-Specific Quality of Life Questionnaire (MSQ), Migraine Disability Questionnaire and Leeds Dependence Questionnaire in predicting a response after a successful withdrawal treatment in patients with MOH. METHODS: This ancillary study is part of a randomized trial that demonstrated the safety and the efficacy of a 3-month treatment with sodium valproate (VPA) (800 mg/day vs placebo) in MOH. Demographic and clinical characteristics and questionnaire results were obtained from the entire sample. RESULTS: A significant correlation was found only between MOH relapse and the total MSQ score, the Role Preventive sub-scale and the Emotional Function sub-scale, suggesting a poorer quality of life in non responders. CONCLUSION: A high MSQ score could be associated with a poor short-term outcome in MOH patients after a successful treatment with detoxification followed by a new treatment.

Long term headache duration is a factor predicting nonresponse to detoxification and advice in medication overuse headache.

BACKGROUND: Medication overuse headache (MOH) is a very heterogeneous disorder for which a recommended treatment is not yet available. The purpose of this study was to investigate any possible roles of demographic and clinical characteristics of MOH patients that might predict a response to detoxification and advice with or without preventive treatment. FINDINGS: This ancillary study is part of the Sodium vAlproate in the treatment of Medication Overuse HeadAche (SAMOHA) study that randomized 88 MOH patients for 3-month treatment period with sodium valproate (VPA) (800 mg/day) or placebo after a 6-day outpatient detoxification regimen. Demographic and clinical characteristics obtained on patients from both study arms were analyzed to point out an association with the response to the treatment. While for patients from VPA arm no significant results were obtained, comparing responders to non-responders to detoxification and advice to withdraw from MOH, a significant difference in headache duration was observed. Specifically, the efficacy of such treatment resulted ineffective in headache lasting longer than 30 years. CONCLUSIONS: Our findings suggest that the benefit from detoxification and advice can be excluded in MOH of long duration. Therefore, a preventive treatment is suggested particularly for these patients.

Sodium valproate in migraine without aura and medication overuse headache: a randomized controlled trial.

OBJECTIVE: To assess the efficacy, safety and tolerability of sodium valproate (800mg/die) compared with placebo in medication-overuse headache patients with a history of migraine without aura. METHODS: This is a multicenter, randomized, double-blind, placebo-controlled study enrolled medication-overuse headache patients for a 3-month treatment period with sodium valproate (800mg/day) or placebo after a 6 day outpatient detoxification regimen, followed by a 3-month follow-up. Primary outcome was defined by the proportion of patients achieving ≥50% reduction in the number of days with headache per month (responders) from the baseline to the last 4 weeks of the 3-month treatment. Multivariate logistic regression models were used on the primary endpoint, adjusting for age, sex, disease duration, comorbidity and surgery. The last-observation-carried-forward method was used to adjust for missing values. RESULTS: Nine sites enrolled 130 patients and, after a 6-day detoxification phase, randomized 88 eligible patients. The 3-month responder rate was higher in the sodium valproate (45.0%) than in the placebo arm (23.8%) with an absolute difference of about 20% (p=0.0431). Sodium valproate had safety and tolerability profiles comparable to placebo. CONCLUSIONS: The present study supports the efficacy and safety of sodium valproate in the treatment of medication overuse headache with history of migraine after detoxification.

Critical role of calcitonin gene-related peptide receptors in cortical spreading depression.

Cortical spreading depression (CSD) is a key pathogenetic step in migraine with aura. Dysfunctions of voltage-dependent and receptor-operated channels have been implicated in the generation of CSD and in the pathophysiology of migraine. Although a known correlation exists between migraine and release of the calcitonin gene-related peptide (CGRP), the possibility that CGRP is involved in CSD has not been examined in detail. We analyzed the pharmacological mechanisms underlying CSD and investigated the possibility that endogenous CGRP contributes to this phenomenon. CSD was analyzed in rat neocortical slices by imaging of the intrinsic optical signal. CSD was measured as the percentage of the maximal surface of a cortical slice covered by the propagation of intrinsic optical signal changes during an induction episode. Reproducible CSD episodes were induced through repetitive elevations of extracellular potassium concentration. AMPA glutamate receptor antagonism did not inhibit CSD, whereas NMDA receptor antagonism did inhibit CSD. Blockade of voltage-dependent sodium channels by TTX also reduced CSD. CSD was also decreased by the antiepileptic drug topiramate, but not by carbamazepine. Interestingly, endogenous CGRP was released in the cortical tissue in a calcium-dependent manner during CSD, and three different CGRP receptor antagonists had a dose-dependent inhibitory effect on CSD, suggesting a critical role of CGRP in this phenomenon. Our findings show that both glutamate NMDA receptors and voltage-dependent sodium channels play roles in CSD. They also demonstrate that CGRP antagonism reduces CSD, supporting the possible use of drugs targeting central CGRP receptors as antimigraine agents.

Occipital arteriovenous malformations and migraine.

BACKGROUND: Headache has been reported to be the first clinical presentation in several patients with cerebral arteriovenous malformations (AVMs). Headache associated with AVMs often shows characteristics of migraine with and without aura. Angiographic characteristics of AVMs, such as their location, could determine the 'migraine-like' features of attacks. METHODS: We performed an observational study of the clinical and angiographic characteristics of a cohort of 40 consecutive patients with AVMs who had been admitted to our institute for endovascular embolization over a 4-year period. Headache was characterized according to ICHD-II criteria. The relationship between headaches and the angioarchitectural features of AVMs was also analysed. RESULTS: Migraine-like headache was the first clinical manifestation in 22.5% of patients. The location of the malformation was significantly associated with migraine-like presentation (p=0.03) and the occipital lobe was the predominant site. CONCLUSIONS: An occipital location may be linked with spreading depression, a pathogenic mechanism of migraine. Headache associated with arteriovenous malformations in the occipital lobe, although secondary in nature, could have clinical features similar to migraine.

Antiepileptic drugs in migraine: from clinical aspects to cellular mechanisms.

Migraine and epilepsy share several clinical features, and epilepsy is a comorbid condition of migraine. Clinical studies have shown that some antiepileptic drugs are effective at preventing migraine attacks. A rationale for their use in migraine prophylaxis is the hypothesis that migraine and epilepsy share several common pathogenetic mechanisms. An imbalance between excitatory glutamate-mediated transmission and GABA-mediated inhibition in specific brain areas has been postulated in these two pathological conditions. Moreover, abnormal activation of voltage-operated ionic channels has been implicated in both migraine and epilepsy. Cortical spreading depression has been found to be involved in the pathophysiology of epilepsy, in addition to the generation of migraine aura.

Antiepileptic drugs as a possible neuroprotective strategy in brain ischemia.

Several new antiepileptic drugs (AEDs) have been introduced for clinical use recently. These new AEDs, as did the classic AEDs, target multiple cellular sites both pre- and postsynaptically. The major common goal of the pharmacological treatment using AEDs is to counteract abnormal brain excitability by either decreasing excitatory transmission or enhancing neuronal inhibition. Interestingly, an excessive release of excitatory amino acids and a reduced neuronal inhibition also occur in brain ischemia. Thus, recently, the use of AEDs as a possible neuroprotective strategy in brain ischemia is receiving increasing attention, and many AEDs have been tested in animal models of stroke, providing encouraging results. Experimental studies utilizing global or focal ischemia in rodents have provided insights into the possible neuroprotective action of the various AEDs. However, the implication of these studies in the treatment of acute stroke in humans is not always direct. In fact, various clinical studies with drugs targeting the same voltage- and ligand-gated channels modulated by most of the AEDs failed to show neuroprotection. The differential mechanisms that underlie the development of focal ischemic injury in experimental animal models versus human stroke require further investigation to open a new therapeutic perspective for neuroprotection that might be applicable in the future.

Ionotropic glutamate receptors: still a target for neuroprotection in brain ischemia? Insights from in vitro studies.

Although experimental studies have widely shown that the pharmacological blockade of ionotropic glutamate receptors reduces ischemic damage, clinical trials with classical AMPA and NMDA glutamate receptor antagonists have provided negative results. To address the involvement of ionotropic glutamate receptors in ischemic damage, corticostriatal brain slices were prepared from adult rats. Extracellular recordings were performed in the striatum after stimulation of the glutamatergic corticostriatal fibres. In vitro ischemia was induced for a 10-min period by omitting oxygen and glucose from the external medium. Under control conditions, ischemia produced an irreversible loss of the corticostriatal field potential amplitude, AP5, a competitive NMDA receptor antagonist, induced a slight rescue of the potential, while ifenprodil, a positive modulator of the proton sensor of the NMDA receptors, allowed a complete recovery from the ischemic insult. Similar neuroprotection was achieved by utilizing either CNQX, a broad spectrum AMPA receptors antagonist, or Joro spider toxin, a selective blocker of calcium permeable AMPA receptors. Interestingly, while CNZX also fully suppressed physiological excitatory transmission, Joro spider toxin was ineffective on this parameter. Finally, lamotrigine and remacemide, two antiepileptic drugs that differentially affect excitatory transmission, exerted neuroprotective effects against ischemia. Noticeably, a combination of low concentrations of these two drugs exerted a stronger neuroprotection than a single drug given in isolation. Thus, it might be possible to reach a neuroprotective action by utilizing doses of these compounds low enough to avoid side effects. Our experimental data still support the idea that a negative modulation of excitatory transmission can be neuroprotective against ischemia. In addition, our findings support the concept that it is possible to produce a significant neuroprotective action in the absence of a relevant interference with normal synaptic transmission.