ß-(Z)-Selective alkyne hydrosilylation by a N,O-functionalized NHC-based rhodium(I) catalyst.

Neutral and cationic cyclooctadiene rhodium(I) complexes with a lutidine-derived polydentate ligand having NHC and methoxy side-donor functions, [RhBr(cod)(κC-tBuImCH2PyCH2OMe)] and [Rh(cod)(κ2C,N-tBuImCH2PyCH2OMe)]PF6, have been prepared. Carbonylation of the cationic compound yields the dicarbonyl complex [Rh(CO)2(κ2C,N-tBuImCH2PyCH2OMe)]PF6 whereas carbonylation of the neutral compound affords a mixture of di- and monocarbonyl neutral complexes [RhBr(CO)2(κC-tBuImCH2PyCH2OMe)] and [RhBr(CO)(κ2C,N-tBuImCH2PyCH2OMe)]. These complexes efficiently catalyze the hydrosilylation of 1-hexyne with HSiMe2Ph with a marked selectivity towards the ß-(Z)-vinylsilane product. Catalyst [RhBr(CO)(κ2C,N-tBuImCH2PyCH2OMe)] showed a superior catalytic performance, in terms of both activity and selectivity, and has been applied to the hydrosilylation of a range of 1-alkynes and phenylacetylene derivatives with diverse hydrosilanes, including HSiMe2Ph, HSiMePh2, HSiPh3 and HSiEt3, showing excellent ß-(Z) selectivity for the hydrosilylation of linear aliphatic 1-alkynes. Hydrosilylation of internal alkynes, such as diphenylacetylene and 1-phenyl-1-propyne, selectively affords the syn-addition vinylsilane products. The ß-(Z) selectivity of these catalysts contrasts with that of related rhodium(I) catalysts based on 2-picolyl-functionalised NHC ligands, which were reported to be ß-(E) selective. An energy barrier ΔG‡ of 19.8 ± 2.0 kcal mol-1 (298 K) has been determined from kinetic studies on the hydrosilylation of 1-hexyne with HSiMe2Ph. DFT studies suggest that the methoxy-methyl group is unlikely to be involved in the activation of hydrosilane, and then hydrosilane activation is likely to proceed via a classical Si-H oxidative addition.

Copper-Catalyzed Azide-Alkyne Cycloaddition (CuAAC) by Functionalized NHC-Based Polynuclear Catalysts: Scope and Mechanistic Insights.

Copper(I) [Cu2(µ-Br)2(tBuImCH2pyCH2L)] n (L = OMe, NEt2, NHtBu) compounds supported by flexible functionalized NHC-based polydentate ligands have been prepared in a one-pot procedure by reacting the corresponding imidazolium salt with an excess of copper powder and Ag2O. An X-ray diffraction analysis has revealed that [Cu2(µ-Br)2(tBuImCH2pyCH2NEt2)] n is a linear coordination polymer formed by bimetallic [Cu(µ-Br)]2 units linked by the lutidine-based NHC-py-NEt2 ligand, which acts as a heteroditopic ligand with a 1κC-2κ2 N,N' coordination mode. We propose that the polymeric compounds break down in the solution into more compact tetranuclear [Cu2(µ-Br)2(tBuImCH2pyCH2L)]2 compounds with a coordination mode identical to the functionalized NHC ligands. These compounds have been found to exhibit high catalytic activity in the Cu-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. In particular, [Cu2(µ-Br)2(tBuImCH2pyCH2NEt2)]2 efficiently catalyzes the click reaction of a range of azides and alkynes, under an inert atmosphere at room temperature in neat conditions at a very low catalyst loading, to quantitatively afford the corresponding 1,4-disubstituted 1,2,3-triazole derivatives in a few minutes. The cycloaddition reaction of benzyl azide to phenylacetylene can be performed at 25-50 ppm catalyst loading by increasing the reaction time and/or temperature. Reactivity studies have shown that the activation of the polynuclear catalyst precursor involves the alkyne deprotonation by the NHC moiety of the polydentate ligand to afford a copper(I)-alkynyl species bearing a functionalized imidazolium ligand. DFT calculations support the participation of the dinuclear species [(CuBr)2(µ-tBuImCH2pyCH2NEt2)], resulting from the fragmentation of the tetranuclear compound, as the catalytically active species. The proposed reaction pathway proceeds through zwitterionic dinuclear intermediates and entails the active participation of both copper atoms, as well as the NHC moiety as an internal base, which activates the reacting alkyne via deprotonation.

Tolerability and safety of galcanezumab in patients with chronic cluster headache with up to 15 months of galcanezumab treatment.

OBJECTIVE: The objective of the study was to assess the tolerability and safety of galcanezumab in patients with chronic cluster headache (CH) with up to 15 months of treatment. BACKGROUND: Chronic CH is a highly debilitating disease with a substantial and unmet medical need. METHODS: Patients were randomized to receive placebo or galcanezumab (300 mg) monthly for 12 weeks, followed by an optional 52-week open-label extension and 16-week posttreatment follow-up (washout). This is a secondary analysis and long-term follow-up of a previously conducted clinical trial. The safety analysis included patients who received galcanezumab at any time during the study. Outcomes included adverse events (AEs), discontinuations, laboratory values, vital signs, electrocardiograms (ECGs), and suicidality ratings. RESULTS: A total of 233 patients received at least one galcanezumab dose. The mean exposure was 341 days. Galcanezumab-treated patients were mostly male (n = 169/233; 72.5%) with a mean age of 44.9 (±10.9) years. Treatment-emergent adverse events (TEAEs) were reported by 185 patients (n = 185/233; 79.4%), 23 patients (n = 23/233; 9.9%) reported serious adverse events (SAEs), and 18 patients (n = 18/233; 7.7%) discontinued due to AEs. The SAE CH was reported by three patients. The most common TEAEs (>10%) were nasopharyngitis (n = 41/233; 17.6%) and injection site pain (n = 33/233; 14.2%). 27.5% of patients (n = 64/233) had TEAEs related to injection sites. Likely hypersensitivity events, including injection site rash, injection site urticaria, and injection site hypersensitivity were reported (n = 14/233; 6.0%). There were past histories of suicidal ideation (n = 55/237; 23.2%) and suicidal behavior (n = 9/236; 3.8%). During the study, 15 patients (n = 15/230; 6.5%), seven with previous history, reported suicidal ideation. One patient had a nonfatal suicide attempt during the open-label extension and an aborted attempt during the washout. There were no new safety findings compared with the placebo-controlled treatment period in laboratory values, vital signs, or ECGs. CONCLUSIONS: Galcanezumab 300 mg monthly had a favorable tolerability and safety profile in patients with chronic CH with up to 15 months of treatment.

Safety and efficacy of galcanezumab in patients for whom previous migraine preventive medication from two to four categories had failed (CONQUER): a multicentre, randomised, double-blind, placebo-controlled, phase 3b trial.

BACKGROUND: Many patients who require migraine preventive treatment have not been able to tolerate or have not responded to multiple previous preventive medications. We aimed to assess the safety and efficacy of galcanezumab, an antibody to calcitonin gene-related peptide, in patients with migraine who had not benefited from preventive medications from two to four categories. METHODS: CONQUER was a multicentre, randomised, double-blind, placebo-controlled, phase 3b trial done at 64 sites (hospitals, clinics, or research centres) in 12 countries (Belgium, Canada, Czech Republic, France, Germany, Hungary, Japan, the Netherlands, South Korea, Spain, the UK, and the USA). Patients were 18-75 years of age, with episodic or chronic migraine, with migraine onset before the age of 50 years, who had a documented failure of preventive medications from two to four drug categories in the past 10 years owing to lack of efficacy or tolerability, or both. Patients were randomised 1:1 to receive subcutaneous placebo or galcanezumab 120 mg per month (with a 240 mg loading dose administered as two 120 mg injections) for 3 months. For masking purposes, patients receiving placebo also received two injections during the first dosing visit. Randomisation was done by a computer-generated random sequence by means of an interactive web-response system stratified by country and migraine frequency (low frequency episodic migraine, four to fewer than eight migraine headache days per month; high frequency episodic migraine, eight to 14 migraine headache days per month and fewer than 15 headache days per month; chronic migraine, at least eight migraine headache days per month and at least 15 headache days per month). The primary endpoint was the overall mean change from baseline in number of monthly migraine headache days during the 3-month treatment period in all patients who were randomly assigned and received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT03559257, and is now completed. FINDINGS: Between Sept 10, 2018, and March 21, 2019, 462 participants with episodic (269 [58%]) or chronic (193 [42%]) migraine were randomly assigned and received at least one injection with placebo (n=230) or galcanezumab (n=232). Galcanezumab-treated patients had significantly greater reduction in migraine headache days versus placebo across months 1-3. The galcanezumab group had on average 4·1 fewer monthly migraine headache days compared with baseline (13·4), while the placebo group had on average 1·0 fewer than at baseline (13·0; between-group difference -3·1 [95% CI -3·9 to -2·3]; p<0·0001; effect size=0·72). Types and number of treatment-emergent adverse events were similar between galcanezumab and placebo. Treatment-emergent adverse events were reported in 122 (53%) of 230 patients in the placebo group and 119 (51%) of 232 patients in the galcanezumab group. There were four serious adverse events during the study, two (1%) reported in the placebo group and two (1%) reported in the galcanezumab group. INTERPRETATION: Galcanezumab was superior to placebo in the preventive treatment of migraine and was safe and well tolerated in patients for whom multiple previous standard-of-care preventive treatments had failed. Galcanezumab might represent an important treatment option for patients who have not benefited from or tolerated previous standard-of-care treatments. FUNDING: Eli Lilly.

The neurology of COVID-19 revisited: A proposal from the Environmental Neurology Specialty Group of the World Federation of Neurology to implement international neurological registries.

A comprehensive review of the neurological disorders reported during the current COVID-19 pandemic demonstrates that infection with SARS-CoV-2 affects the central nervous system (CNS), the peripheral nervous system (PNS) and the muscle. CNS manifestations include: headache and decreased responsiveness considered initial indicators of potential neurological involvement; anosmia, hyposmia, hypogeusia, and dysgeusia are frequent early symptoms of coronavirus infection. Respiratory failure, the lethal manifestation of COVID-19, responsible for 264,679 deaths worldwide, is probably neurogenic in origin and may result from the viral invasion of cranial nerve I, progressing into rhinencephalon and brainstem respiratory centers. Cerebrovascular disease, in particular large-vessel ischemic strokes, and less frequently cerebral venous thrombosis, intracerebral hemorrhage and subarachnoid hemorrhage, usually occur as part of a thrombotic state induced by viral attachment to ACE2 receptors in endothelium causing widespread endotheliitis, coagulopathy, arterial and venous thromboses. Acute hemorrhagic necrotizing encephalopathy is associated to the cytokine storm. A frontal hypoperfusion syndrome has been identified. There are isolated reports of seizures, encephalopathy, meningitis, encephalitis, and myelitis. The neurological diseases affecting the PNS and muscle in COVID-19 are less frequent and include Guillain-Barré syndrome; Miller Fisher syndrome; polyneuritis cranialis; and rare instances of viral myopathy with rhabdomyolysis. The main conclusion of this review is the pressing need to define the neurology of COVID-19, its frequency, manifestations, neuropathology and pathogenesis. On behalf of the World Federation of Neurology we invite national and regional neurological associations to create local databases to report cases with neurological manifestations observed during the on-going pandemic. International neuroepidemiological collaboration may help define the natural history of this worldwide problem.

Clinical Subtypes of Medication Overuse Headache - Findings From a Large Cohort.

BACKGROUND: The International Classification of Headache Disorders lists different subtypes of medication overuse headache (MOH), according to the medication overused. The aim of this study is to evaluate whether the different subtypes correspond to clinically distinguishable phenotypes in a large population. METHOD: This descriptive cross-sectional observational study included 660 patients with MOH referred to headache centers in Europe and Latin America as a part of the COMOESTAS project. Information about clinical features was collected with structured patient interviews and with self-administered questionnaires for measuring disability, anxiety, and depression. RESULTS: Female/male ratio, body mass index, marital status, and level of education were similar among in subjects enrolled in the 5 centers. The mean age was higher among subjects overusing triptans (T-MOH) with respect to subjects overusing simple analgesic (A-MOH). Duration of headache before chronification was longer in T-MOH (19.2 ± 11.9 years) and in subjects overusing ergotamines (E-MOH, 17.8 ± 11.7 years) with respect to the A-MOH group (13.1 ± 10.9; P < .001 and P = .017, respectively) and in T-MOH with respect multiple drug classes (M-MOH, 14.9 ± 11.7; P = .030). Migraine Disability Assessment (MIDAS) score was significantly lower in E-MOH group (33.6 ± 41.6), while T-MOH group (56.8 ± 40.6) had a significant lower MIDAS score with respect to M-MOH (67.2 ± 62.5; P = .016 and P = .037, respectively). Prevalence of depression and anxiety was lower in patients overusing T with respect to other groups of patients (χ2  = 10.953, P = .027 and χ2  = 25.725, P < .001, respectively). CONCLUSION: In this study on a large and very well characterized population of MOH, we describe the distinctive clinical characteristics of MOH subtypes. These findings contribute to more clearly define the clinical picture of a poorly delineated headache disorder. They also provide some insights in the possible trajectories leading to this highly disabling chronic headache, that is classified as a secondary form, but whose occurrence is entirely dependent on an underlying primary headache.

Non-invasive vagus nerve stimulation (nVNS) for the preventive treatment of episodic migraine: The multicentre, double-blind, randomised, sham-controlled PREMIUM trial.

INTRODUCTION: Non-invasive vagus nerve stimulation (nVNS; gammaCore®) has the potential to prevent migraine days in patients with migraine on the basis of mechanistic rationale and pilot clinical data. METHODS: This multicentre study included a 4-week run-in period, a 12-week double-blind period of randomised treatment with nVNS or sham, and a 24-week open-label period of nVNS. Patients were to administer two 120-second stimulations bilaterally to the neck three times daily (6-8 hours apart). RESULTS: Of 477 enrolled patients, 332 comprised the intent-to-treat (ITT) population. Mean reductions in migraine days per month (primary outcome) were 2.26 for nVNS (n = 165; baseline, 7.9 days) and 1.80 for sham (n = 167; baseline, 8.1 days) (p = 0.15). Results were similar across other outcomes. Upon observation of suboptimal adherence rates, post hoc analysis of patients with ≥ 67% adherence per month demonstrated significant differences between nVNS (n = 138) and sham (n = 140) for outcomes including reduction in migraine days (2.27 vs. 1.53; p = 0.043); therapeutic gains were greater in patients with aura than in those without aura. Most nVNS device-related adverse events were mild and transient, with application site discomfort being the most common. CONCLUSIONS: Preventive nVNS treatment in episodic migraine was not superior to sham stimulation in the ITT population. The "sham" device inadvertently provided a level of active vagus nerve stimulation. Post hoc analysis showed significant effects of nVNS in treatment-adherent patients. Study identification and registration: PREMIUM; NCT02378844; https://clinicaltrials.gov/ct2/show/NCT02378844.

Economic benefits of treating medication-overuse headache - results from the multicenter COMOESTAS project.

BACKGROUND: Medication-overuse headache is a costly disease for individuals and society. OBJECTIVE: To estimate the impact of medication-overuse headache treatment on direct and indirect headache-related health care costs. METHODS: This prospective longitudinal study was part of the COMOESTAS project (COntinuous MOnitoring of Medication Overuse Headache in Europe and Latin America: development and STAndardization of an Alert and decision support System). Patients with medication-overuse headache were included from four European and two Latin American headache centers. Costs of acute medication, costs of health care services, and measurements of productivity were calculated at baseline and at 6-month follow-up Treatment consisted of overused drug withdrawal with optional preventive medication. RESULTS: A total of 475 patients (71%) completed treatment and were followed up for 6 months. Direct health care costs were on average reduced significantly by 52% ( p < 0.001) for the total study population. Significant reductions were seen in both number of consumed tablets (-71%, p < 0.001) and number of visits to physicians (-43%, p < 0.001). Fifty percent of patients reduced their number of consumed tablets ≥ 80%. Headache-related productivity loss, calculated either as absence from work or ≥ 50% reduction of productivity during the workday, were reduced by 21% and 34%, respectively ( p < 0.001). CONCLUSION: Standardized treatment of medication-overuse headache in six countries significantly reduced direct health care costs and increased productivity. This emphasizes the importance of increasing awareness of the value of treating medication-overuse headache. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov (no. NCT02435056).

Psychological, clinical, and therapeutic predictors of the outcome of detoxification in a large clinical population of medication-overuse headache: A six-month follow-up of the COMOESTAS Project.

AIM: To identify factors that may be predictors of the outcome of a detoxification treatment in medication-overuse headache. METHODS: Consecutive patients entering a detoxification program in six centres in Europe and Latin America were evaluated and followed up for 6 months. We evaluated anxious and depressive symptomatology (though patients with severe psychiatric comorbidity were excluded), quality of life, headache-related disability, headache characteristics, and prophylaxis upon discharge. RESULTS: Of the 492 patients who completed the six-month follow up, 407 ceased overuse following the detoxification (non overusers), another 23 ceased overuse following detoxification but relapsed during the follow-up. In the 407 non-overusers, headache acquired an episodic pattern in 287 subjects (responders). At the multivariate analyses, lower depression scores (odds ratio = 0.891; p = 0.001) predicted ceasing overuse. The primary headache diagnosis - migraine with respect to tension-type headache (odds ratio = 0.224; p = 0.001) or migraine plus tension-type headache (odds ratio = 0.467; p = 0.002) - and the preventive treatment with flunarizine (compared to no such treatment) (odds ratio = 0.891; p = 0.001) predicted being a responder. A longer duration of chronic headache (odds ratio = 1.053; p = 0.032) predicted relapse into overuse. Quality of life and disability were not associated with any of the outcomes. CONCLUSIONS: Though exploratory in nature, these findings point to specific factors that are associated with a positive outcome of medication-overuse headache management, while identifying others that may be associated with a negative outcome. Evaluation of the presence/absence of these factors may help to optimize the management of this challenging groups of chronic headache sufferers.

Preventive effects of galcanezumab in adult patients with episodic or chronic migraine are persistent: data from the phase 3, randomized, double-blind, placebo-controlled EVOLVE-1, EVOLVE-2, and REGAIN studies.

BACKGROUND: Maintenance of effect following treatment with galcanezumab compared to placebo in adult patients with episodic or chronic migraine was evaluated. METHODS: In 2 similarly designed studies of patients with episodic migraine (6 months) and 1 study of patients with chronic migraine (3 months), patients randomized in a 1:1:2 ratio received a subcutaneous injection of galcanezumab 120 mg/month (after an initial loading dose of 240 mg) or 240 mg/month or placebo. Maintenance of effect during the double-blind phase was evaluated based on a comparison of the percentages of galcanezumab- and placebo-treated patients with maintenance of 30, 50, 75, and 100% response (defined as ≥30, ≥50, ≥75, and 100% reduction from baseline in monthly migraine headache days [MHD]) at an individual patient level. Logistic regression analyses were used for between treatment comparisons. RESULTS: A total of 1773 adult patients with episodic migraine (n = 444 for galcanezumab 120 mg; n = 435 for galcanezumab 240 mg; n = 894 for placebo for 2 studies pooled) and 1113 patients with chronic migraine (n = 278 for galcanezumab 120 mg; n = 277 for galcanezumab 240 mg; n = 558 for placebo) were evaluated. In patients with episodic migraine, ≥50% response was maintained in 41.5 and 41.1% of galcanezumab-treated patients (120 mg and 240 mg, respectively) for ≥3 consecutive months (until patient's endpoint) and 19.0 and 20.5%, respectively, for 6 consecutive months and was significantly greater than the 21.4 and 8.0% of placebo-treated patients at ≥3 and 6 months consecutively (P < 0.001). Approximately 6% of galcanezumab-treated patients maintained ≥75% response all 6 months versus 2% of placebo-treated patients. Few galcanezumab-treated patients maintained 100% response. In patients with chronic migraine, 29% of galcanezumab-treated patients maintained ≥30% response all 3 months compared to 16% of placebo patients while ≥50% response was maintained in 16.8 and 14.6% of galcanezumab-treated patients (120 mg and 240 mg) and was greater than placebo (6.3%; p < 0.001). Few patients maintained ≥75% response. CONCLUSIONS: Treatment with galcanezumab 120 mg or 240 mg demonstrated statistically significant and clinically meaningful persistence of effect in patients with episodic migraine (≥3 and 6 consecutive months) and in patients with chronic migraine (for 3 months). STUDY IDENTIFICATION AND TRIAL REGISTRATION: Study Identification: EVOLVE-1 (I5Q-MC-CGAG); EVOLVE-2 (I5Q-MC-CGAH); REGAIN (I5Q-MC-CGAI) TRIAL REGISTRATION: ClinicalTrials.gov ; NCT02614183 (EVOLVE-1); NCT02614196 (EVOLVE-2); NCT02614261 (REGAIN).

Comorbidity between idiopathic overactive bladder and chronic migraine.

Objective We tested whether overactive bladder (OAB) and chronic migraine (CM) could be comorbid. Patients and methods CM women, aged 40-69 years, answered a validated OAB questionnaire. Prevalence data were compared with those reported in our country in the general population (GP) using the same questionnaire. Results We interviewed 231 CM women. Eighty-four met OAB criteria. OAB prevalence in CM patients was significantly higher than that found in the GP (36.4% vs. 21.8% in the GP; p = 0.0001). There were 34 CM women aged 40-49 years (34.3% vs. 15.2%; p = 0.001), 35 aged 50-59 years (38.9% vs. 21.7%; p = 0.004) and 15 aged 60-69 years (35.7% vs. 24.5%; p = 0.15) meeting OAB criteria. Seventy-seven (33% vs. 9.9%; p = 0.002) needed more than eight micturitions/24 h, 61 (26.4% vs. 8.1%, p = 0.002) experienced nocturia and 43 (18.6% vs. 8.1%; p = 0.001) urinary incontinence. Conclusion In this exploratory study, at least in women, OAB and CM are comorbid, which suggests shared mechanisms.

Changes in anxiety and depression symptoms associated to the outcome of MOH: A post-hoc analysis of the Comoestas Project.

Aims To evaluate the impact of treatment success on depression and anxiety symptoms in medication-overuse headache (MOH) and whether depression and anxiety can be predictors of treatment outcome. Methods All consecutive patients entering the detoxification program were analysed in a prospective, non-randomised fashion over a six-month period. Depression and anxiety were assessed using the Hospital Anxiety and Depression Scale. Results A total of 663 MOH patients were evaluated, and 492 completed the entire protocol. Of these, 287 ceased overuse and reverted to an episodic pattern (responders) and 23 relapsed into overuse. At the final evaluation, the number of patients with depressive symptoms was reduced by 63.2% among responders ( p < 0.001) and did not change in relapsers ( p = 0.13). Anxious symptomatology was reduced by 43.1% in responders ( ps < 0.001) and did not change in relapsers ( p = 0.69). At the multivariate analysis, intake of a prophylactic drug and absence of symptoms of depression at six months emerged as prognostic factors for being a responder (OR 2.406; p = 0.002 and OR 1.989; p = 0.019 respectively), while lack of antidepressant drugs and presence of symptoms of depression at six months were prognostic factors for relapse into overuse (OR 3.745; p = 0.004 and OR 3.439; p = 0.031 respectively). Conclusions Symptomatology referred to affective state and anxiety can be significantly reduced by the treatment of MOH. Baseline levels of depression and anxiety do not generally predict the outcome at six months. Their persistence may represent a trait of patients with a negative outcome, rather than the consequence of a treatment failure.

Cluster headache and other TACs: Pathophysiology and neurostimulation options.

BACKGROUND: The trigeminal autonomic cephalalgias (TACs) are highly disabling primary headache disorders. There are several issues that remain unresolved in the understanding of the pathophysiology of the TACs, although activation of the trigeminal-autonomic reflex and ipsilateral hypothalamic activation both play a central role. The discovery of the central role of the hypothalamus led to its use as a therapeutic target. After the good results obtained with hypothalamic stimulation, other peripheral neuromodulation targets were tried in the management of refractory cluster headache (CH) and other TACs. METHODS: This review is a summary both of CH pathophysiology and of efficacy of the different neuromodulation techniques. RESULTS: In chronic cluster headache (CCH) patients, hypothalamic deep brain stimulation (DBS) produced a decrease in attack frequency of more than 50% in 60% of patients. Occipital nerve stimulation (ONS) also elicited favorable outcomes with a reduction of more than 50% of attacks in around 70% of patients with medically intractable CCH. Stimulation of the sphenopalatine ganglion (SPG) with a miniaturized implanted stimulator produced a clinically significant improvement in 68% of patients (acute, preventive, or both). Vagus nerve stimulation (VNS) with a portable device used in conjunction with standard of care in CH patients resulted in a reduction in the number of attacks. DBS and ONS have been used successfully in some cases of other TACs, including hemicrania continua (HC) and short-lasting unilateral headache attacks (SUNHA). CONCLUSIONS: DBS has good results, but it is a more invasive technique and can generate serious adverse events. ONS has good results, but frequent and not serious adverse events. SPG stimulation (SPGS) is also efficacious in the acute and prophylactic treatment of refractory cluster headache. At this moment, ONS and SPG stimulation techniques are recommended as first line therapy in refractory cluster patients. New recent non-invasive approaches such as the non-invasive vagal nerve stimulator (nVNS) have shown efficacy in a few trials and could be an interesting alternative in the management of CH, but require more testing and positive randomized controlled trials.

Sphenopalatine ganglion stimulation in cluster headache and other types of headache.

Objectives The cluster headache is the most excruciatingly painful primary headache. In some patients, neither preventive treatment nor acute treatment is effective or treatment is poorly tolerated. The sphenopalatine ganglion (SPG) has an important role in the pathophysiology of cluster headache and, for this reason, SPG stimulation has been used to treat cluster headache. Methods We have reviewed the published literature on the role of the SPG in cluster headache and the use of different treatments targeting the SPG. Results Multiple procedures have been used over the SPG to treat pain and trigemino-autonomic symptoms in patients with refractory cluster headache. After obtaining good results in a small number of patients, a miniaturized stimulator was developed. Stimulation of the SPG with this device proved to be efficacious in acute and preventive treatment in a clinical trial involving patients with chronic refractory cluster headache. Implantation of the device is minimally invasive and the most frequent side-effects are mild, such as paraesthesia and pain over the maxillary area. In patients who have used the SPG device for longer than one year, the therapeutic effect remains effective and the side-effects decrease. Conclusions The reported studies have demonstrated that SPG stimulation is a safe and effective treatment for chronic cluster headache. Long-term studies have shown that the effect remains over time and this treatment could be a good choice in patients with chronic refractory headache. We need more data about its potential use in other forms of headache, such as other trigemino-autonomic headaches or migraine.

Noninvasive neuromodulation in cluster headache.

PURPOSE OF REVIEW: Neuromodulation is an alternative in the management of medically intractable cluster headache patients. Most of the techniques are invasive, but in the last 2 years, some studies using a noninvasive device have been presented. The objective of this article is to review the data using this approach. RECENT FINDINGS: Techniques as occipital nerve stimulation or sphenopalatine ganglion stimulation are recommended as first-line therapy in refractory cluster patients, but they are invasive and maybe associated with complications. Noninvasive vagal nerve stimulation with an external device has been tried in cluster patients. Results from clinical practice and a single randomized clinical trial have been presented showing a reduction of the number of cluster attacks/week in the patients treated with the device. The rate of adverse events was low and most of them were mild. SUMMARY: In the last decade, invasive neuromodulation treatments have demonstrated good efficacy in cluster refractory patients. Noninvasive approaches such as the noninvasive vagal nerve stimulation have shown efficacy in one trial and could be an easier alternative in the management of this debilitating headache. We need to replicate these results with further controlled studies and conduct basic research in order to clarify the mechanism of action.

Medication overuse headache in Europe and Latin America: general demographic and clinical characteristics, referral pathways and national distribution of painkillers in a descriptive, multinational, multicenter study.

BACKGROUND: Medication overuse headache (MOH) is a very disabling and costly disorder due to indirect costs, medication and healthcare utilization. The aim of the study was to describe general demographic and clinical characteristics of MOH, along with the national referral pathways and national painkillers distribution in several European and Latin American (LA) Countries. METHODS: This descriptive cross-sectional observational study included 669 patients with MOH referred to headache-centers in Europe and LA as a part of the COMOESTAS project. Information about acute medication and healthcare utilization were collected by extensive questionnaires, supplemented with structured patient interviews. RESULTS: Triptans were overused by 31 % European patients and by 6 % in LA (p < 0.001), whereas ergotamines were overused by 4 % in Europe and 72 % in LA (p < 0.001). Simple analgesics were overused by 54 % in Europe and by 33 % in LA (p < 0.001), while combination-analgesics were more equally overused (24 % in Europe and 29 % in LA). More European patients (57 %) compared with LA patients (27 %) visited general practitioners (p < 0.001), and 83 % of European patients compared to 38 % in LA consulted headache specialists (p < 0.001). A total of 20 % in Europe and 30 % in LA visited emergency rooms (p = 0.007). CONCLUSION: There are marked variations between LA and Europe in healthcare pathways and in acute medication overuse regarding patients with MOH. This should be considered when planning prevention campaigns against MOH.

Sphenopalatine ganglion stimulation for the treatment of cluster headache.

Cluster headache is a severe, debilitating disorder with pain that ranks among the most severe known to humans. Patients with cluster headaches have few therapeutic options and further, 10-20% develop drug-resistant attacks. The often brief duration of cluster attacks makes abortive therapy a challenge, and preventive medications are almost always provided to patients, but the side effects of these preventive medications can be significant. The sphenopalatine ganglion (SPG) is believed to play a role in headache pain and cranial autonomic symptoms associated with cluster headache, which is a result of activation of the trigeminal-autonomic reflex. For over 100 years, the SPG has been a clinical target to treat primary headache disorders using pharmacologic and nonpharmacologic methods. Radiofrequency lesioning and nerve-resection therapies, while initially beneficial, are irreversible procedures, and the use of neurostimulation provides one method of interfacing with the neural pathways without causing permanent damage to neural tissue. SPG neurostimulation is both reversible and adjustable, and has recently been tested in both proof-of-concept work and in a randomized, sham-controlled trial for the treatment of cluster headache. A randomized, sham-controlled study of 32 patients was performed to evaluate further the use of SPG stimulation for the acute treatment of chronic cluster headache. Of the 32 patients, 28 completed the randomized experimental period. Overall, 68% of patients experienced an acute response, a frequency response, or both. In this study the majority of adverse events were related to the implantation procedure, which typically resolved or remained mild in nature at 3 months following the implant procedure. This and other studies highlight the promise of using SPG stimulation to treat the pain-associated cluster headache. SPG stimulation could be a safe and effective option for chronic cluster headache.

Stimulation of the sphenopalatine ganglion in intractable cluster headache: expert consensus on patient selection and standards of care.

CONTEXT AND OVERVIEW: Chronic cluster headache (CCH) is a debilitating headache disorder with a significant impairment of the patients' lives. Within the past decade, various invasive neuromodulatory approaches have been proposed for the treatment of CCH refractory to standard preventive drug, but only very few randomized controlled studies exist in the field of neuromodulation for the treatment of drug-refractory headaches. Based on the prominent role of the cranial parasympathetic system in acute cluster headache attacks, high-frequency sphenopalatine ganglion (SPG) stimulation has been shown to abort ongoing attacks in some patients in a first small study. As preventive effects of SPG-stimulation have been suggested and the rate of long-term side effects was moderate, SPG stimulation appears to be a promising new treatment strategy. AIMS AND CONCLUSION: As SPG stimulation is effective in some patients and the first commercially available CE-marked SPG neurostimulator system has been introduced for cluster headache, patient selection and care should be standardized to ensure maximal efficacy and safety. As only limited data have been published on SPG stimulation, standards of care based on expert consensus are proposed to ensure homogeneous patient selection and treatment across international headache centres. Given that SPG stimulation is still a novel approach, all expert-based consensus on patient selection and standards of care should be re-reviewed when more long-term data are available.

Optimal management of severe nausea and vomiting in migraine: improving patient outcomes.

Migraine is a common and potentially disabling disorder for patients, with wide-reaching implications for health care services, society, and the economy. Nausea and vomiting during migraine attacks are common symptoms that affect at least 60% of patients suffering from migraines. These symptoms are often more disabling than the headache itself, causing a great burden on the patient's life. Nausea and vomiting may delay the use of oral abortive medication or interfere with oral drug absorption. Therefore, they can hinder significantly the management and treatment of migraine (which is usually given orally). The main treatment of pain-associated symptoms of migraine (such as nausea and vomiting) is to stop the migraine attack itself as soon as possible, with the effective drugs at the effective doses, seeking if necessary alternative routes of administration. In some cases, intravenous antiemetic drugs are able to relieve a migraine attack and associated symptoms like nausea and vomiting. We performed an exhaustive PubMed search of the English literature to find studies about management of migraine and its associated symptoms. Search terms were migraine, nausea, and vomiting. We did not limit our search to a specific time period. We focused on clinical efficacy and tolerance of the various drugs and procedures based on data from human studies. We included the best available studies for each discussed drug or procedure. These ranged from randomized controlled trials for some treatments to small case series for others. Recently updated books and manuals on neurology and headache were also consulted. We herein review the efficacy of the different approaches in order to manage nausea and vomiting for migraine patents.