Cluster Headache, SUNCT, and SUNA

OBJECTIVE

This article reviews the epidemiology, clinical features, differential diagnosis, pathophysiology, and management of three types of trigeminal autonomic cephalalgias: cluster headache (the most common), short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA).

LATEST DEVELOPMENTS

The first-line treatments for trigeminal autonomic cephalalgias have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil, and SUNCT and SUNA are managed with lamotrigine. However, new successful clinical trials of high-dose prednisone, high-dose galcanezumab, and occipital nerve stimulation provide additional options for patients with cluster headache. Furthermore, new genetic and imaging tests in patients with cluster headache hold promise for a better understanding of its pathophysiology.

ESSENTIAL POINTS

The trigeminal autonomic cephalalgias are a group of diseases that appear similar to each other and other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment.

One-year prevalence of cluster headache, hemicrania continua, paroxysmal hemicrania and SUNCT in Norway: a population-based nationwide registry study

BACKGROUND

There is lack of population-based studies evaluating the prevalence of paroxysmal hemicrania, hemicrania continua and short-lasting unilateral neuralgiform headache attacks.

OBJECTIVES

The aim of this study was to investigate the gender-specific 1-year prevalence of cluster headache, paroxysmal hemicrania, hemicrania continua, and short-lasting unilateral neuralgiform headache attacks.

METHODS

A nationwide study was conducted from January 1 2022 and December 31 2022 by linking diagnostic codes from Norwegian Patient Registry and prescription of relevant drugs from Norwegian Prescription Database on an individual basis. The 1-year prevalence with 95% confidence intervals (CI) of cluster headache, paroxysmal hemicrania, hemicrania continua and short-lasting unilateral neuralgiform headache attacks are estimated based on the combination of diagnostic codes, prescription of drugs and corresponding reimbursement codes.

RESULTS

Among 4,316,747 individuals aged ≥ 18 years, the 1-year prevalence per 100,000 was 14.6 (95% CI 13.5-15.8) for cluster headache, 2.2 (95% CI 1.8-2.7) for hemicrania continua, 1.4 (95% CI 1.0-1.8) for paroxysmal hemicrania, and 1.2 (95% CI 0.8-1.4) for short-lasting unilateral neuralgiform headache attacks. For all the trigeminal autonomic cephalalgies, cluster headache included, the prevalence was higher for women than men.

CONCLUSIONS

In this nationwide register-based study, we found a 1-year prevalence per 100,100 of 14.6 for cluster headache, 2.2 for hemicranias continua, 1.4 for paroxysmal hemicranias, and 1.2 for short-lasting unilateral neuralgiform headache attacks. This is the first study reporting higher prevalence of cluster headache for women than men.

Translating the Cluster Headache Quality of Life Questionnaire (CHQ) from English to Dutch with the TRAPD method

OBJECTIVE

Cluster headache is associated with a decreased quality of life (QoL). The increased focus on patient-reported outcome measures (PROMS) has led to the creation of a tailored Cluster Headache Quality of Life scale (CHQ). Our objective was to create and authenticate a Dutch version of the CHQ (CHQ-D).

METHODS

The TRAPD model (Translation, Review, Adjudication, Pretesting, Documentation) was used to translate the CHQ from English to Dutch and ensure cross-cultural adaption. Pre-testing was performed in n = 31 participants, and validity was in a new sample of n = 40 participants who completed the CHQ twice at a 2-day interval. Intraclass correlation coefficient (ICC) and Cronbach's alpha were used to assess the validity and reproducibility of the CHQ-D.

RESULTS

To produce the CHQ-D, we made five modifications based on pretesting. Participants finished the questionnaire in a median time of 10 min (IQR:10.0, 17.5) and 90% within 20 min. The majority of participants (74.2%) did not find it burdensome at all. The reliability of the CHQ-D was excellent (Cronbach's alpha: 0.94; ICC: 0.94).

CONCLUSION

The CHQ-D is a valid and practical instrument for QoL in individuals with cluster headache. We aim to use CHQ-D as PROM in clinical research in the Netherlands to enforce international collaborations and comparisons of studies.

Reduced plasma calcitonin gene-related peptide level identified in cluster headache: A prospective and controlled study

BACKGROUND

The role of calcitonin gene-related peptide (CGRP) in the cyclic pattern of cluster headache is unclear. To acquire biological insight and to comprehend why only episodic cluster headache responds to CGRP monoclonal antibodies, we examined whether plasma CGRP changes between disease states (i.e. bout, remission and chronic) and controls.

METHODS

The present study is a prospective case-control study. Participants with episodic cluster headache were sampled twice (bout and remission). Participants with chronic cluster headache and controls were sampled once. CGRP concentrations were measured in plasma with a validated radioimmunoassay.

RESULTS

Plasma was collected from 201 participants diagnosed with cluster headache according to the International Classification of Headache Disorders, 3rd edition, and from 100 age- and sex-matched controls. Overall, plasma CGRP levels were significantly lower in participants with cluster headache compared to controls (p < 0.05). In episodic cluster headache, CGRP levels were higher in bout than in remission (mean difference: 17.1 pmol/L, 95% confidence interval = 9.8-24.3, p < 0.0001). CGRP levels in bout were not different from chronic cluster headache (p = 0.266).

CONCLUSIONS

Plasma CGRP is unsuitable as a diagnostic biomarker of cluster headache or its disease states. The identified reduced CGRP levels suggest that CGRPs role in cluster headache is highly complex and future investigations are needed into the modulation of CGRP and its receptors.

Profile of Chinese Cluster Headache Register Individual Study (CHRIS): Clinical characteristics, diagnosis and treatment status data of 816 patients in China

BACKGROUND

The clinical profile of cluster headache may differ among different regions of the world, warranting interest in the data obtained from the initial Chinese Cluster Headache Register Individual Study (CHRIS) for better understanding.

METHODS

We conducted a multicenter, prospective, longitudinal cohort study on cluster headache across all 31 provinces of China, aiming to gather clinical characteristics, treatment approaches, imaging, electrophysiological and biological samples.

RESULTS

In total 816 patients were enrolled with a male-to-female ratio of 4.33:1. The mean age at consultation was 34.98 ± 9.91 years, and 24.89 ± 9.77 years at onset. Only 2.33% were diagnosed with chronic cluster headache, and 6.99% had a family history of the condition. The most common bout was one to two times per year (45.96%), lasting two weeks to one month (44.00%), and occurring frequently in spring (76.23%) and winter (73.04%). Of these, 68.50% experienced one to two attacks per day, with the majority lasting one to two hours (45.59%). The most common time for attacks was between 9 am and 12 pm (75.86%), followed by 1 am and 3 am (43.48%). Lacrimation (78.80%) was the most predominant autonomic symptom reported. Furthermore, 39.22% of patients experienced a delay of 10 years or more in receiving a correct diagnosis. Only 35.67% and 24.26% of patients received common acute and preventive treatments, respectively.

CONCLUSION

Due to differences in ethnicity, genetics and lifestyle conditions, CHRIS has provided valuable baseline data from China. By establishing a dynamic cohort with comprehensive multidimensional data, it aims to advance the management system for cluster headache in China.

Biomarkers in cluster headache: A systematic review

OBJECTIVE

To systematically investigate previously examined biomarkers in blood, urine, cerebrospinal fluid, tear fluid, and saliva of patients with cluster headache.

BACKGROUND

Cluster headache is a condition with extensive clinical challenges in terms of diagnosis and treatment. Identification of a biomarker with diagnostic implications or as a potential treatment target is highly warranted.

METHODS

We conducted a systematic review including peer reviewed full text of studies that measured biochemical compounds in either blood, urine, cerebrospinal fluid, tear fluid, or saliva of patients with cluster headache diagnosed after the implementation of the International Classification of Headache Disorders (1988) written in English, Danish, Swedish, or Norwegian. Inclusion required a minimum of five participants. The search was conducted in PubMed and EMBASE, in September 2022, and extracted data were screened by two authors. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for reporting systematic reviews were followed. The Newcastle-Ottawa Scale was used to assess the risk of bias in case-controlled studies.

RESULTS

We included 40 studies involving 832 patients with cluster headache and 872 controls, evaluating 80 potential biomarkers. The risk of bias for case-controlled studies was a median of 6 (range: 3-8) and 20 studies out of 40 (50%) were of fair or good quality. Most studies were identified within three groups: hypothalamic-regulated hormones, inflammatory markers, and neuropeptides. Among the hypothalamic hormones, cortisol was the most frequently investigated (N = 7) and was elevated in cluster headache in most of the studies. The most frequently examined inflammatory marker was interleukin 1 (N = 3), but findings were divergent. Calcitonin gene-related peptide was the most investigated neuropeptide (N = 9) and all studies found increased levels during attacks.

CONCLUSION

Biomarker findings have been inconsistent and widely non-specific for cluster headache, which explains why none of the previous studies succeeded in identifying a unique biomarker for cluster headache, but instead contributed to substantiating the underlying pathophysiologic mechanisms. Several of the examined biomarkers could hold promise as markers for disease activity but are unfit for a clear distinction from both controls and other headaches.

An atypical survey in a cluster headache patient: A case report

Cluster headache is a rare, severe headache associated with hypothalamic dysfunction or sleep cycles. It is classified in the primary headache group in The International Classification of Headache Disorders-3-2018 (ICHD-3-2018). In this case report, we present a 62-year-old male patient whose cluster headache showed a five times longer remission interval after dental implant treatment and ceased for more than two years following cardiac stent therapy.

Patients with chronic cluster headache may show reduced activity energy expenditure on ambulatory wrist actigraphy recordings during daytime attacks

OBJECTIVE

To investigate the changes in activity energy expenditure (AEE) throughout daytime cluster headache (CH) attacks in patients with chronic CH and to evaluate the usefulness of actigraphy as a digital biomarker of CH attacks.

BACKGROUND

CH is a primary headache disorder characterized by attacks of severe to very severe unilateral pain (orbital, supraorbital, temporal, or in any combination of these sites), with ipsilateral cranial autonomic symptoms and/or a sense of restlessness or agitation. We hypothesized increased AEE from hyperactivity during attacks measured by actigraphy.

METHODS

An observational study including patients with chronic CH was conducted. During 21 days, patients wore an actigraphy device on the nondominant wrist and recorded CH attack-related data in a dedicated smartphone application. Accelerometer data were used for the calculation of AEE before and during daytime CH attacks that occurred in ambulatory settings, and without restrictions on acute and preventive headache treatment. We compared the activity and movements during the pre-ictal, ictal, and postictal phases with data from wrist-worn actigraphy with time-concordant intervals during non-headache periods.

RESULTS

Four patients provided 34 attacks, of which 15 attacks met the eligibility criteria for further analysis. In contrast with the initial hypothesis of increased energy expenditure during CH attacks, a decrease in movement was observed during the pre-ictal phase (30 min before onset to onset) and during the headache phase. A significant decrease (p < .01) in the proportion of high-intensity movement during headache attacks, of which the majority were oxygen-treated, was observed. This trend was less present for low-intensity movements.

CONCLUSION

The unexpected decrease in AEE during the pre-ictal and headache phase of daytime CH attacks in patients with chronic CH under acute and preventive treatment in ambulatory settings has important implications for future research on wrist actigraphy in CH.

Clinical characteristics and treatment patterns of patients with episodic cluster headache: results from the United States, United Kingdom and Germany

OBJECTIVE

To describe clinical characteristics and regional treatment patterns of episodic cluster headache (CH).

METHODS

A point-in-time survey of physicians and their patients with CH was conducted in the United States, United Kingdom and Germany in 2017.

RESULTS

Overall, 1012 patients with episodic CH were analyzed. Demographic and clinical findings were generally consistent across regions. Most patients were men (66.6%) and the mean age was 40.9 years. The greatest proportion of patients (38.3%) had ≤1 attack per day. The mean number of attacks per day (APD) was 2.4 and mean number of cluster periods per year was 2.6; the mean cluster period duration was 30.8 days. Most patients (69.3%) did not report a specific or predicable time when cluster periods occurred. Acute treatment was prescribed for 47.6% of patients, 10.3% of patients received preventive treatment, and 37.9% of patients received combined acute and preventive treatment; 4.2% of patients were not receiving treatment. Frequently prescribed acute treatments were sumatriptan, oxygen, and zolmitriptan; oxygen use varied considerably across countries and was prescribed least often in the United States. Frequently prescribed preventive treatments were verapamil, topiramate, and lithium. Lack of efficacy and tolerability were the most common reasons for discontinuing preventive treatment.

CONCLUSIONS

We observed high use of acute treatments, but only half of patients used preventive treatments despite experiencing several cluster periods per year with multiple cluster APD. Further studies about the need for and benefits of preventive treatment for episodic CH are warranted.

A prospective open label 2-8 year extension of the randomised controlled ICON trial on the long-term efficacy and safety of occipital nerve stimulation in medically intractable chronic cluster headache

BACKGROUND

We demonstrated in the randomised controlled ICON study that 48-week treatment of medically intractable chronic cluster headache (MICCH) with occipital nerve stimulation (ONS) is safe and effective. In L-ICON we prospectively evaluate its long-term effectiveness and safety.

METHODS

ICON participants were enrolled in L-ICON immediately after completing ICON. Therefore, earlier ICON participants could be followed longer than later ones. L-ICON inclusion was stopped after the last ICON participant was enrolled in L-ICON and followed for ≥2 years by completing six-monthly questionnaires on attack frequency, side effects, subjective improvement and whether they would recommend ONS to others. Primary outcome was the change in mean weekly attack frequency 2 years after completion of the ICON study compared to baseline. Missing values for log-transformed attack-frequency were imputed for up to 5 years of follow-up. Descriptive analyses are presented as (pooled) geometric or arithmetic means and 95% confidence intervals.

FINDINGS

Of 103 eligible participants, 88 (85%) gave informed consent and 73 (83%) were followed for ≥2 year, 61 (69%) ≥ 3 year, 33 (38%) ≥ 5 years and 3 (3%) ≥ 8.5 years. Mean (±SD) follow-up was 4.2 ± 2.2 years for a total of 370 person years (84% of potentially 442 years). The pooled geometric mean (95% CI) weekly attack frequency remained considerably lower after one (4.2; 2.8-6.3), two (5.1; 3.5-7.6) and five years (4.1; 3.0-5.5) compared to baseline (16.2; 14.4-18.3). Of the 49/88 (56%) ICON ≥50% responders, 35/49 (71%) retained this response and 15/39 (38%) ICON non-responders still became a ≥50% responder for at least half the follow-up period. Most participants (69/88; 78% [0.68-0.86]) reported a subjective improvement from baseline at last follow-up and 70/88 (81% [0.70-0.87]) would recommend ONS to others. Hardware-related surgery was required in 44/88 (50%) participants in 112/122 (92%) events (0.35 person-year-1 [0.28-0.41]). We didn't find predictive factors for effectiveness.

INTERPRETATION

ONS is a safe, well-tolerated and long-term effective treatment for MICCH.

FUNDING

The Netherlands Organisation for Scientific Research, the Dutch Ministry of Health, the NutsOhra Foundation from the Dutch Health Insurance Companies, and Medtronic.

Epidemiology, burden and clinical spectrum of cluster headache: a global update

BACKGROUND

This narrative review aims to broaden our understanding of the epidemiology, burden and clinical spectrum of cluster headache based on updated findings with a global perspective.

METHODS

We conducted a literature search on the following topics: (a) epidemiology; (b) burden: quality of life, disability, economic burden, job-related burden and suicidality; and (c) clinical spectrum: male predominance and its changes, age, pre-cluster and pre-attack symptoms, aura, post-drome, attack characteristics (location, severity, duration and associated symptoms), bout characteristics (attack frequency, bout duration and bout frequency), circadian and seasonal rhythmicity and disease course.

RESULTS

New large-scale population-based reports have suggested a lower prevalence than previous estimations. The impact of cluster headache creates a significant burden in terms of the quality of life, disability, economic and job-related burdens and suicidality. Several studies have reported decreasing male-to-female ratios and a wide age range at disease onset. The non-headache phases of cluster headache, including pre-cluster, pre-attack and postictal symptoms, have recently been revisited. The latest data regarding attack characteristics, bout characteristics, and circadian and seasonal rhythmicity from different countries have shown variability among bouts, attacks, individuals and ethnicities. Studies on the disease course of cluster headache have shown typical characteristics of attacks or bouts that decrease with time.

CONCLUSIONS

Cluster headache may be more than a "trigeminal autonomic headache" because it involves complex central nervous system phenomena. The spectrum of attacks and bouts is wider than previously recognised. Cluster headache is a dynamic disorder that evolves or regresses over time.

Unilateral corneal arcus and conjunctival vessel alterations in cranial autonomic dysregulation: A case report

BACKGROUND

Cranial autonomic dysregulation is a common symptom of patients suffering from cluster headache or migraine. The peripheral vascular dysfunction may increase the risk for ischemic or hemorrhagic strokes, myocardial infarction, retinal vasculopathy, cardiovascular mortality, and peripheral artery diseases. Furthermore, it may also manifest with ocular symptoms, e.g., increased lacrimation, conjunctival injection, and facial swelling.

CASE PRESENTATION

We here report a case of a patient with migraine and ocular signs of a vascular dysregulation that have led to persisting changes of conjunctival vessels and to a corneal arcus.

CONCLUSIONS

Autonomic vascular dysregulation may not only cause headaches but also persisting changes of ocular tissues, e.g., conjunctival vessel alterations and a corneal arcus.

Oxygen inhalation has no effect on provoked cranial autonomic symptoms using kinetic oscillation stimulation in healthy volunteers

OBJECTIVE

Inhalation of oxygen is highly effective in cluster headache, a subtype of trigeminal autonomic cephalgias. Since oxygen has no effect on nociceptive pain, the mechanism of action is still unknown. The present study investigated whether oxygen inhalation modifies the trigeminal autonomic reflex arc in healthy volunteers.

METHODS

21 healthy volunteers participated in a randomized, placebo controlled, double-blind, cross-over, and within-subject study design. In a randomized order demand valve inhalation of 100% oxygen or medical air were administered. Capillary blood samples were collected to control for blood gas changes. Cranial parasympathetic output (lacrimation) was provoked using kinetic oscillation stimulation of the nasal mucosa. Standardized measurement of lacrimation between baseline and kinetic oscillation stimulation served as a measure of induced cranial autonomic output.

RESULTS

There was no significant difference in parasympathetic output after oxygen inhalation when compared to inhalation of medical air.

CONCLUSION

The inhalation of 100% oxygen does not affect the parasympathetic reflex arc of the trigeminal autonomic reflex.

Management of Trigeminal Autonomic Cephalalgias Including Chronic Cluster: A Review

Importance

Trigeminal autonomic cephalalgias (TACs) comprise a unique collection of primary headache disorders characterized by moderate or severe unilateral pain, localized in in the area of distribution of the first branch of the trigeminal nerve, accompanied by cranial autonomic symptoms and signs. Most TACs are rare diseases, which hampers the possibility of performing randomized clinical trials and large studies. Therefore, knowledge of treatment efficacy must be based only on observational studies, rare disease registries, and case reports, where real-world data and evidence play an important role in health care decisions.

Observations

Chronic cluster headache is the most common of these disorders, and the literature offers some evidence from randomized clinical trials to support the use of pharmacologic and neurostimulation treatments. Galcanezumab, a monoclonal antibody targeting the calcitonin gene-related peptide, was not effective at 3 months in a randomized clinical trial but showed efficacy at 12 months in a large case series. For the other TACs (ie, paroxysmal hemicrania, hemicrania continua, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing, and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms), only case reports and case series are available to guide physicians in everyday management.

Conclusions and Relevance

The accumulation of epidemiologic, pathophysiologic, natural history knowledge, and data from case series and small controlled trials, especially over the past 20 years from investigators around the world, has added to the previously limited evidence and has helped advance and inform the treatment approach to rare TACs, which can be extremely challenging for clinicians.

[Autonomic Disorders in Trigeminal Autonomic Cephalalgias: An Update]

The term trigeminal autonomic cephalalgias (TACs) was introduced in the 2^nd edition of the International Classification of Headache Disorders, and has been retained in the 3^rd edition. TACs include cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks, hemicrania continua, and probable trigeminal autonomic cephalalgia. Headaches classified as TACs share clinical features with unilateral headache and usually present with prominent lateralized and ipsilateral cranial parasympathetic autonomic features, including the following: (1) conjunctival injection and/or lacrimation, (2) nasal congestion and/or rhinorrhea, (3) eyelid edema, (4) forehead and facial sweating, (5) miosis and/or ptosis. "Clinical Practice Guideline for Headache 2021 (Japanese version)" will serve as a useful aid for diagnosis and treatment of TACs. Currently, hypothalamic activation, activation of the trigeminal-autonomic nerve reflex, internal carotid artery dilatation, and the action of some neuropeptides are implicated as pathophysiological mechanisms underlying TACs; however, it is not unequivocal. Further studies are warranted to gain deeper insight into several unclear aspects associated with TACs.

Refractory Orofacial Pain: Is It the Patient or the Pain?

AIMS

To highlight and discuss the term "refractory" when used to describe pain conditions and its application to orofacial pain, as well as to highlight the factors that must be considered in a refractory patient.

METHODS

A scoping review of recent publications (2010 to 2021) applying the term "refractory" to orofacial pain was conducted, and this paper presents their limitations and definitions.

RESULTS

The term "refractory" is often used to describe pain instead of "persistent" or "nonresponsive." There are clear definitions in the use of refractory for migraine, cluster headaches, and other nonheadache disorders. Currently, the term is applied to pain conditions in order to alter the patient pathway of treatment, sometimes to escalate a patient from one care sector to another and sometimes to escalate treatment to more costly surgical interventional techniques.

CONCLUSION

There is a need for a clear definition for use of the term "refractory" in orofacial pain conditions, excluding migraine and cluster headaches. In addition, there is a requirement for a consensus on the implications of the use of refractory when assessing and managing patients.

Cluster Headache: Rapid Evidence Review

Cluster headache, the most common form of trigeminal autonomic cephalgia, is a rare primary headache disorder that affects less than 1% of the population. The mean age of onset is 30 years, and it is two to three times more common in males. Cluster headache consists of attacks of severe unilateral pain located in the orbital, supraorbital, and/or temporal region that occur from every other day up to eight times per day and last from 15 to 180 minutes. The pain is associated with ipsilateral autonomic symptoms (most commonly lacrimation, conjunctival injection, nasal congestion or rhinorrhea, ptosis, edema of the eyelid, sweating of the forehead or face, and miosis) and a sense of agitation or restlessness. Attacks occur in clusters, called bouts, and are episodic or chronic. Common triggers include alcohol, nitroglycerin, food containing nitrates, and strong odors. Abortive treatments include triptans and oxygen; transitional treatments include steroids and suboccipital steroid injections; and prophylactic treatments include verapamil, lithium, melatonin, and topiramate. Newer treatments for cluster headache include galcanezumab, neurostimulation, and somatostatin receptor agonists.

A brief diagnostic screen for cluster headache: Creation and initial validation of the Erwin Test for Cluster Headache

OBJECTIVE

To use 1) newly generated data, 2) existing evidence, and 3) expert opinion to create and validate a new cluster headache screening tool.

METHODS

In phase 1 of the study, we performed a prospective study of an English translation of an Italian screen on 95 participants (45 with cluster headache, 17 with other trigeminal autonomic cephalalgias, 30 with migraine, and 3 with trigeminal neuralgia). In phase 2, we performed a systematic review in PubMed of all studies until September 2019 with diagnostic screening tools for cluster headache. In phase 3, a 6-person panel of cluster headache patients, research coordinators, and headache specialists analyzed the data from the first two phases to generate a new diagnostic screening tool. Finally, in phase 4 this new screen was validated on participants at a single headache center (all diagnoses) and through research recruitment (trigeminal autonomic cephalalgias only, as recruitment was essential but was otherwise low).

RESULTS

In total, this study included 319 unique participants including 109 cluster headache participants (95 total participants/45 cluster headache participants in phase 1, and 224 total participants/64 cluster headache participants in phase 4). It also found 123 articles on potential screening tools in our systematic review. In phase 1, analysis of the English translation of an Italian screen generated 7 questions with high sensitivity and specificity against migraine, trigeminal neuralgia, and other trigeminal autonomic cephalalgias, but had grammatical and other limitations as a general screening tool. In phase 2, the systematic review revealed nine studies that met inclusion criteria as diagnostic screening tools for cluster headache, including four where sensitivity and specificity were available for individual questions or small groups of questions. In phase 3, this data was reviewed by the expert panel to generate a brief (6-item), binary (yes/no), written screening test. In phase 4, a total of 224 participants completed the new 6-item screening test (81 migraine, 64 cluster headache, 21 other trigeminal autonomic cephalalgias, 35 secondary headaches, 7 neuralgias, 5 probable migraine, and 11 other headache disorders). Answers to the 6 items were combined in a decision tree algorithm and three items had a sensitivity of 84% (confidence interval or 95% confidence interval 73-92%), specificity of 89% (95% confidence interval 84-94%), positive predictive value of 76% (95% confidence interval 64-85%), and negative predictive value of 93% (95% confidence interval 88-97%) for the diagnosis of cluster headache. These three items focused on headache intensity, duration, and autonomic features.

CONCLUSION

The 3-item Erwin Test for Cluster Headache is a promising diagnostic screening tool for cluster headache.

Secondary cluster headache and numb chin syndrome as initial manifestation of high-grade B-lymphoma: a case report

BACKGROUND

Cluster headache is a primary condition characterized by severe headache accompanied by trigeminal autonomic signs. By definition, it is not attributed to underlying etiologies; however, under certain clinical characteristics, secondary etiologies must be ruled out.

CASE PRESENTATION

We present the case of a 48-year-old Hispanic man with a history of episodic right orbital pain, lasting 30 minutes, associated with ipsilateral tearing, who prior to the onset of his symptoms reported loss of appetite, weight loss, and paresthesias in the right chin region. After work-up studies, high-grade lymphoma with infiltration to the right submental nerve was diagnosed, in which numb chin syndrome was the initial presentation. Despite initiation of treatment, the patient died 3 weeks after the diagnosis.

CONCLUSIONS

In the study of cluster headache, underlying etiologies must be considered when there are atypical clinical manifestations. Within these etiologies, metastases to pericranial nerves must be included, which, besides generating localized symptoms, can activate the trigeminal vascular system simulating headaches of primary etiology.

Essential oils and cluster headache: insights from two cases

Essential oils with proconvulsive properties are known to cause seizures and may worsen migraine. Here, we report two cases of cluster headache temporally related to the use of toothpastes containing essential oils of camphor and eucalyptus.

Cluster Headache and Other Trigeminal Autonomic Cephalalgias

PURPOSE OF REVIEW

The trigeminal autonomic cephalalgias (TACs) are relatively rare, but they represent a distinct set of syndromes that are important to recognize. Despite their unique features, TACs often go undiagnosed or misdiagnosed for several years, leading to unnecessary pain and suffering. A significant proportion of TAC presentations may have secondary causes.

RECENT FINDINGS

The underlying pathophysiology of TACs is likely rooted in hypothalamic dysfunction and derangements in the interplay of circuitry involving trigeminovascular, trigeminocervical, trigeminoautonomic, circadian, and nociceptive systems. Recent therapeutic advancements include a better understanding of how to use older therapies more effectively and the identification of new approaches.

SUMMARY

TAC syndromes are rare but important to recognize because of their debilitating nature and greater likelihood for having potentially serious underlying causes. Although treatment options have remained somewhat limited, scientific inquiry is continually advancing our understanding of these syndromes and how best to manage them.

Cluster headache and TACs: state of the art

Cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache attacks (including SUNCT and SUNA), and hemicrania continua (HC) compose the group of trigeminal autonomic cephalalgias (TACs). Here, we review the recent advances in the field and summarize the current knowledge about the origin of these headaches. Similar to the other primary headaches, the pathogenesis is still much obscure. However, advances are being made in both animal models and humans studies. Three structures clearly appear to be crucial in the pathophysiology of TACs: the trigeminal nerve, the facial parasympathetic system, and the hypothalamus. The physiologic and pathologic functioning of each of these elements and their interactions is being progressively clarified, but critical questions are still open.

[New Management of Cluster Headache]

Galcanezumab, a CGRP monoclonal antibody drug, has been approved by the U.S. Food and Drug Administration (FDA) for the prevention of recurrent cluster headaches. This was done after a randomized, double-blind, placebo-controlled trial found it to be effective and safe. Similarly sphenopalatine ganglion stimulation has been found to be effective and safe in a randomized, controlled trial as an acute treatment for chronic cluster headache. This article reviews the mechanisms of action of these therapies and their clinical trial results, clinical uses, and prospects in Japan.

Chronic Cluster Headache with a Pediatric Onset: The First Japanese Case Report

A 9-year-old female reported left-sided, excruciatingly severe, stabbing orbital pain with cranial autonomic symptoms. The attacks continued for 1 year with a remission period of 2 months. Each attack duration was approximately 120 minutes with a frequency of two to three times a day. The patient was diagnosed with chronic cluster headache (CCH) according to the third edition of the International Classification of Headache Disorders. A combination of low-dose verapamil and lomerizine once a week decreased the frequency of the attacks, and oral sumatriptan became an effective abortive therapy. No case reports of pediatric CCH have been previously published in Japan.

Cluster Headache: Opportunities for Pharmacists to Improve Care

Cluster headache (CH) is a primary headache (PH) disorder characterized by recurrent attacks of severe/extremely severe unilateral pain and associated symptoms. While less prevalent than other PHs such as migraine, CH impact is substantial given the agonizing pain, negative effect on daily productivity, impaired mental health, and increased costs. Cluster headache is not optimally treated and few clinical trials are available to model therapy, especially dosing and administration. Pharmacists are well positioned to help prescribers and CH individuals with several key opportunities. Subcutaneous sumatriptan (SC SM) lower than the FDA-approved 6 mg per attack, specifically 2 mg and 3 mg, can be considered; literature describes these doses' benefits. Moreover, lower doses may improve patient access to this treatment-of-choice. Despite the SC SM's FDA-approved dose limit of 12 mg per 24 hours, the maximum CH dose has not been examined; this limit merits reevaluation since literature and clinical experience illustrate treatment exceeding this limit. Oxygen therapy for CH remains unfamiliar to, and under-utilized by, clinicians and CH individuals. Pharmacists can facilitate prescribing, distribution, and administration of oxygen via education. Patient education for the various CH medication devices, including oxygen, is paramount. Narcotics remain widely prescribed for CH, without supporting evidence, but with considerable abuse and diversion risks. Pharmacists are positioned to help guard against narcotic usage and to direct care toward medications endorsed by CH guidelines. Since the optimal method to initiate and discontinue drugs which may decrease CH attacks' remains unknown, pharmacists can educate clinicians and individuals with CH to make fully informed decisions.

[Cluster headache and other trigeminal autonomic cephalalgias]

Trigeminal autonomic cephalalgias (TACs) are a group of 4 different primary headache syndromes that have a lot of pathophysiological and clinical features in common. The 4 different TACs are: cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks and hemicrania continua. TACs are characterized by frequent, strictly unilateral, (very) intense headache attacks with ipsilateral cranial autonomic symptoms or intrinsic restlessness or both. A distinction can be made between the 4 TACs on the basis of the duration and frequency of the headache attacks. The treatment of cluster headache consists of an acute treatment and a maintenance treatment. Headache attacks in the context of paroxysmal hemicrania and hemicrania continua (almost) always respond to treatment with indomethacin. More and more neuromodulation therapies are becoming available, such as vagus nerve stimulation, stimulation and blocking of the sphenopalatine ganglion, stimulation and blocking of the occipital nerve and deep brain stimulation.

Dynamic Pressure Pain Hypersensitivity as Assessed by Roller Pressure Algometry in Episodic Cluster Headache

BACKGROUND

A method for assessing dynamic muscle hyperalgesia (dynamic pressure algometry) has been developed and applied in tension-type and migraine headaches.

OBJECTIVES

To investigate differences in dynamic pressure pain assessment over the trigeminal area between men with cluster headache (CH) and headache-free controls, and the association between dynamic and static pressure pain sensitivity.

STUDY DESIGN

A case-control study.

SETTING

Tertiary urban hospital.

METHODS

Forty men with episodic CH and 40 matched controls participated. Dynamic pressure pain sensitivity was assessed with a dynamic pressure algometry set consisting of 8 rollers with different fixed levels (500, 700, 850, 1,350, 1,550, 2,200, 3,850, and 5,300 g). Each roller was moved at a speed of 0.5 cm/sec over a diagonal line covering the temporalis muscle from an anterior to posterior direction. The dynamic pressure threshold (DPT; load level of the first painful roller) and the pain intensity perceived at the DPT level (roller-evoked pain) were assessed. Static pressure pain thresholds (PPT) were also assessed with a digital pressure algometer applied statically over the mid-muscle belly of the temporalis. Patients were assessed in a remission phase, at least 3 months from the last cluster attack, and without preventive medication.

RESULTS

Side-to-side consistency between DPTs (r = 0.781, P < 0.001), roller-evoked pain on DPT (r = 0.586; P < 0.001), and PPTs (r = 0.874; P < 0.001) were found in men with CH. DPT was moderately, bilaterally, and side-to-side associated with PPTs (0.663 > r > 0.793, all P < 0.001). Men with CH had bilateral lower DPT and PPT and reported higher levels of roller-evoked pain (all P < 0.001) than headache-free controls.

LIMITATIONS

Only men with episodic CH were included.

CONCLUSIONS

This study supports that a dynamic pressure algometry is as valid as a static pressure algometry for assessing pressure pain sensitivity in patients with CH. Assessing both dynamic and static pain sensitivity may provide new opportunities for differentiated diagnostics.

KEY WORDS

Cluster headache, dynamic pressure pain, pressure pain threshold.

Managing cluster headache

Cluster headache is a neurological disorder that presents with unilateral severe headache associated with ipsilateral cranial autonomic symptoms. Cluster headache attacks often occur more than once a day, and typically manifesting in bouts. It has a point prevalence of 1 in 1000 and is the most common trigeminal autonomic cephalalgia. This article aims to guide general neurologists to an accurate diagnosis and practical management options for cluster headache patients.

Temporal changes of circadian rhythmicity in cluster headache

OBJECTIVE

To investigate the temporal changes of circadian rhythmicity in relation to the disease course in patients with cluster headache.

METHODS

In this multicenter study, patients with cluster headache were recruited between September 2016 and July 2018. We evaluated the patients for circadian rhythmicity and time of cluster headache attacks in the current bout and any experience of bout-to-bout change in circadian rhythmicity. We analyzed the patterns of circadian rhythmicity in relation to the disease progression (the number of total lifetime bouts, grouped into deciles).

RESULTS

Of the 175 patients in their active, within-bout period, 86 (49.1%) had circadian rhythmicity in the current bout. The prevalence of circadian rhythmicity in the active period was overall similar regardless of disease progression. Sixty-three (46.3%) out of 136 patients with ≥2 bouts reported bout-to-bout changes in circadian rhythmicity. The most frequent time of cluster headache attacks was distributed evenly throughout the day earlier in the disease course and dichotomized into hypnic and midday as the number of lifetime bouts increased (p = 0.037 for the homogeneity of variance). When grouped into nighttime and daytime, nighttime attacks were predominant early in the disease course, while daytime attacks increased with disease progression (up to 7th deciles of total lifetime bouts, p = 0.001) and decreased in patients with the most advanced disease course (p = 0.013 for the non-linear association).

CONCLUSIONS

Circadian rhythmicity is not a fixed factor, and changes according to the disease course. Our findings will be valuable in providing a new insight into the stability of functional involvement of the suprachiasmatic nucleus in the pathophysiology of cluster headache.

Burst Occipital Nerve Stimulation for Chronic Migraine and Chronic Cluster Headache

BACKGROUND

Occipital nerve stimulation (ONS) is widely used for headache syndromes including chronic migraine (CM) and chronic cluster headache (CCH). The paraesthesia associated with tonic stimulation can be bothersome and can limit therapy. It is now clear in spinal cord stimulation that paraesthesia-free waveforms can produce effective analgesia, but this has not been reported in ONS for CM or CCH.

MATERIALS AND METHODS

Seventeen patients (12 CM and 5 CCH) were treated with bilateral burst pattern ONS, including 4 who had previously had tonic ONS. Results were assessed in terms of the frequency of headaches (number of headache days per month for CM, and number of attacks per day for CCH) and their intensity on the numeric pain rating scale.

RESULTS

Burst ONS produced a statistically significant mean reduction of 10.2 headache days per month in CM. In CCH, there were significant mean reductions in headache frequency (92%) and intensity (42%).

CONCLUSION

Paraesthesia is not necessary for good quality analgesia in ONS. Larger studies will be required to determine whether the efficacies of the two stimulation modes differ. Burst ONS is imperceptible and therefore potentially amenable to robustly blinded clinical trials.

Effectiveness of Oxygen and Other Acute Treatments for Cluster Headache: Results From the Cluster Headache Questionnaire, an International Survey

OBJECTIVE

To assess the effectiveness and adverse effects of acute cluster headache medications in a large international sample, including recommended treatments such as oxygen, commonly used medications such as opioids, and emerging medications such as intranasal ketamine. Particular focus is paid to a large subset of respondents 65 years of age or older.

BACKGROUND

Large international surveys of cluster headache are rare, as are examinations of treatments and side effects in older cluster headache patients. This article presents data from the Cluster Headache Questionnaire, with respondents from over 50 countries and with the vast majority from the United States, the United Kingdom, and Canada.

METHODS

This internet-based survey included questions on cluster headache diagnostic criteria, which were used as part of the inclusion/exclusion criteria for the study, as well as effectiveness of medications, physical and medical complications, psychological and emotional complications, mood scores, and difficulty obtaining medications. The diagnostic questions were also used to create a separate group of respondents with probable cluster headache. Limitations to the methods include the use of nonvalidated questions, the lack of a formal clinical diagnosis of cluster headache, and the grouping of some medications (eg, all triptans as opposed to sumatriptan subcutaneous alone).

RESULTS

A total of 3251 subjects participated in the questionnaire, and 2193 respondents met criteria for this study (1604 cluster headache and 589 probable cluster headache). Of the respondents with cluster headache, 68.8% (1104/1604) were male and 78.0% (1245/1596) had episodic cluster headache. Over half of respondents reported complete or very effective treatment for triptans (54%, 639/1139) and oxygen (54%, 582/1082). Between 14 and 25% of respondents reported complete or very effective treatment for ergot derivatives (dihydroergotamine 25%, 42/170; cafergot/ergotamine 17%, 50/303), caffeine and energy drinks (17%, 7/41), and intranasal ketamine (14%, 5/37). Less than 10% reported complete or very effective treatment for opioids (6%, 30/541), intranasal capsaicin (5%, 7/151), and intranasal lidocaine (2%, 5/241). Adverse events were especially low for oxygen (no or minimal physical and medical complications 99%, 1077/1093; no or minimal psychological and emotional complications 97%, 1065/1093), intranasal lidocaine (no or minimal physical and medical complications 97%, 248/257; no or minimal psychological and emotional complications 98%, 251/257), intranasal ketamine (no or minimal physical and medical complications 95%, 38/40; no or minimal psychological and emotional complications 98%, 39/40), intranasal capsaicin (no or minimal physical and medical complications 91%, 145/159; no or minimal psychological and emotional complications 94%, 150/159), and caffeine and energy drinks (no or minimal physical and medical complications 89%, 39/44; no or minimal psychological and emotional complications 91%, 40/44). This is in comparison to ergotamine/cafergot (no or minimal physical and medical complications 83%, 273/327; no or minimal psychological and emotional complications 89%, 290/327), dihydroergotamine (no or minimal physical and medical complications 81%, 143/176; no or minimal psychological and emotional complications 91%, 160/176), opioids (no or minimal physical and medical complications 76%, 416/549; no or minimal psychological and emotional complications 77%, 423/549), or triptans (no or minimal physical and medical complications 73%, 883/1218; no or minimal psychological and emotional complications 85%, 1032/1218). A total of 139 of 1604 cluster headache respondents (8.7%) were age 65 and older and reported similar effectiveness and adverse events to the general population. The 589 respondents with probable cluster headache reported similar medication effectiveness to respondents with a full diagnosis of cluster headache.

CONCLUSIONS

Oxygen is reported by survey respondents to be a highly effective treatment with few complications in cluster headache in a large international sample, including those 65 years or over. Triptans are also very effective with some side effects, and newer medications deserve additional study. Patients with probable cluster headache may respond similarly to acute medications as patients with a full diagnosis of cluster headache.

Male and female sex hormones in primary headaches

BACKGROUND

The three primary headaches, tension-type headache, migraine and cluster headache, occur in both genders, but all seem to have a sex-specific prevalence. These gender differences suggest that both male and female sex hormones could have an influence on the course of primary headaches. This review aims to summarise the most relevant and recent literature on this topic.

METHODS

Two independent reviewers searched PUBMED in a systematic manner. Search strings were composed using the terms LH, FSH, progesteron*, estrogen*, DHEA*, prolactin, testosterone, androgen*, headach*, migrain*, "tension type" or cluster. A timeframe was set limiting the search to articles published in the last 20 years, after January 1st 1997.

RESULTS

Migraine tends to follow a classic temporal pattern throughout a woman's life corresponding to the fluctuation of estrogen in the different reproductive stages. The estrogen withdrawal hypothesis forms the basis for most of the assumptions made on this behalf. The role of other hormones as well as the importance of sex hormones in other primary headaches is far less studied.

CONCLUSION

The available literature mainly covers the role of sex hormones in migraine in women. Detailed studies especially in the elderly of both sexes and in cluster headache and tension-type headache are warranted to fully elucidate the role of these hormones in all primary headaches.

Implications for the migraine SNP rs1835740 in a Swedish cluster headache population

BACKGROUND

Cluster headache is a severe headache disorder with unknown aetiology. The pathophysiology and symptoms present certain common features with migraine. Specifically, activation of the trigeminal vascular system seems to be involved in both disorders, which is hypothesized to result in neurogenic inflammation and vasodilation of the cerebral vessels. In addition, genetic factors have been implicated in both migraine and cluster headache.

OBJECTIVE

In order to determine whether or not migraine and cluster headache share genetic risk factors, we screened two genetic variants known to increase the risk of migraine in Sweden in a Swedish cluster headache case-control study population.

METHODS

In all, 541 patients and 581 control subjects were genotyped for rs1835740 in close proximity to MTDH (metadherin) and rs2651899 in the PRDM16 (PR/SET domain 16) gene, using TaqMan® real-time PCR and pyrosequencing. In addition, we analyzed MTDH gene expression in a subset of the material, using reverse transcription real-time PCR to determine relative mRNA levels in primary fibroblast cell lines from patients and controls.

RESULTS

We found a trend for association between rs1835740, which is reported to affect MTDH mRNA levels, and cluster headache in our Swedish case-control material (p = 0.043, Χ2 = 4.102). This association was stronger in a subgroup of patients suffering from both cluster headache and migraine (p = 0.031, Χ2 = 6.964). We could further confirm that rs1835740 has an effect on the transcriptional activity of MTDH. In this Swedish cluster headache cohort we did not find an association with the rs2651899 variant.

CONCLUSIONS

We conclude that rs1835740 is a potential risk factor for cluster headache in Sweden. Our data indicates that rs1835740 and MTDH might be involved in neurovascular headaches in general whilst rs2651899 is specifically related to migraine.

Cluster Headache in a 76-year-old Woman with Onset at the Age of 74: Case Report

Cluster headache (CH) is a rare trigeminal autonomic cephalalgia. Although its pathophysiology is not entirely understood, the hypothalamus and trigeminal nociceptive and autonomic pathways seem to play a key role in its pathology. In the majority of cases, CH begins at a young age and affects mainly men. This article presents a case of a 76-year-old woman with CH that developed at the age of 74. This is one of the first documented reports of CH with such atypical features from an epidemiologic point of view. A possibility of symptomatic cluster-like headache (CLH) attributed to cerebrovascular disease in the patient is also discussed.

Primary Headaches

The primary headaches are composed of multiple entities that cause episodic and chronic head pain in the absence of an underlying pathologic process, disease, or traumatic injury. The most common of these are migraine, tension-type headache, and the trigeminal autonomic cephalalgias. This article reviews the clinical presentation, pathophysiology, and treatment of each to help in differential diagnosis. These headache types share many common signs and symptoms, thus a clear understanding of each helps prevent a delay in diagnosis and inappropriate or ineffective treatment. Many of these patients seek dental care because orofacial pain is a common presenting symptom.

Cluster Headache and Other Trigeminal Autonomic Cephalalgias

PURPOSE OF REVIEW

This article covers the clinical features, differential diagnosis, and management of the trigeminal autonomic cephalalgias (TACs). The TACs are composed of five diseases: cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA), and hemicrania continua.

RECENT FINDINGS

New classifications for the TACs have two important updates; chronic cluster headache is now defined as remission periods lasting less than 3 months (formerly less than 1 month), and hemicrania continua is now classified as a TAC (formerly classified as other primary headache). The first-line treatments of TACs have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil; paroxysmal hemicrania and hemicrania continua are managed with indomethacin; and SUNCT and SUNA are managed with lamotrigine. However, advancements in neuromodulation have recently provided additional options for patients with cluster headache, which include noninvasive devices for abortive therapy and invasive devices for refractory cluster headache. Patient selection for these devices is key.

SUMMARY

The TACs are a group of diseases that appear similar to each other and to other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment. This article reviews the pathophysiology, epidemiology, differential diagnosis, and treatment of the TACs.

OnabotulinumtoxinA in the treatment of refractory chronic cluster headache

BACKGROUND

Cluster headache (CH) is a clinically well-defined primary headache disorder, approximately 20% of cluster headache sufferers experience recurrent attacks without periods of significant remission. For the treatment of chronic cluster headache (CCH) only limited therapeutic options are available.

METHODS

A potential refractory CCH patient group was identified according to the clinical definition of rCCH based on the consensus statement of the European Headache Federation (EHF). Treatment with OnabotulinumtoxinA (BoNT-A; Botox®, 150 Allergan IU) was done according to the PREEMPT study protocol. A standardized headache diary was used for recording frequency, duration of attacks and pain intensity. To assess personal burden the HIT-6 and the Hospital Anxiety and Depression scale was used. Primary outcome measure was a > 50% reduction in headache minutes.

RESULTS

Seventeen male patients suffering from rCCH, aged 32 ± 11 (mean ± SD) years, presenting a mean disease duration of 6.6 years completed the study of 28 weeks. The cut-off point of > 50% reduction in headache minutes as positive result was reached in 58.8%, 29.4% experienced an improvement of 30-50%. Mean frequency of headache days dropped from 28.2 to 11.8 days at week 24 (p = 0.0001; 95% CI -21.33 to - 11.61;). Intensity of remaining attacks was also reduced significantly. Headache disability scores showed a trend to improvement after BoNT-A.

CONCLUSIONS

Encouraging results for the treatment with BoNT-A in rCCH patients were observed in our study population.

Rare primary headaches in Italian tertiary Headache Centres: Three year nationwide retrospective data from the RegistRare Network

Background Rare primary headaches are mainly included in Chapters 3, Trigeminal autonomic cephalalgias, and 4, Other primary headache disorders, Part One of the International Classification of Headache Disorders 3rd edition. Epidemiological data are scarce, mostly emerging from case series or small studies, with the exception of cluster headache. In order to overcome the knowledge gap about rare primary headaches, the RegistRare Network was launched in 2017 to promote research in the field. Methods A retrospective cohort study including patients who, from April 30, 2014 to May 1, 2017, visited seven Italian tertiary Headache Centres, was undertaken to estimate in that clinical setting prevalence and incidence of headaches included in Chapters 3 and 4, Part One of the International Classification of Headache Disorders 3rd edition. Prevalent headache is defined as a headache recorded within the study timeframe, regardless of when the diagnosis was made. Incident headache is defined as a headache diagnosed for the first time in the patient during the study period. Results Twenty thousand and eighty-three patients visited the participating centres, and 822 (4.1%) prevalent cases, of which 461 (2.3%) were incident cases, were registered. Headaches listed in Chapter 3 affected 668 patients, representing 81.3% of the total number of prevalent cases. Headaches listed in Chapter 4 affected 154 patients and represent 18.7% of the total number of prevalent cases. Cluster headaches represent the most frequently diagnosed rare headaches (70.4%). For 13 entities out of 20, no cases were registered in more than 50% (n ≥ 4) of the centres, and for 14 entities more than 50% of diagnoses were incident. Conclusions This large, multicentre study gives the first wide-ranging snapshot of the burden in clinical practice of rare headaches and confirms that cooperative networks are necessary to study rare headaches, as their prevalence is often very low. The launch of a disease registry by the RegistRare Network will favour research in this neglected population of headache patients. Trial registration NCT03416114.

Non-invasive vagus nerve stimulation for the acute treatment of episodic and chronic cluster headache: A randomized, double-blind, sham-controlled ACT2 study

Background Clinical observations and results from recent studies support the use of non-invasive vagus nerve stimulation (nVNS) for treating cluster headache (CH) attacks. This study compared nVNS with a sham device for acute treatment in patients with episodic or chronic CH (eCH, cCH). Methods After completing a 1-week run-in period, subjects were randomly assigned (1:1) to receive nVNS or sham therapy during a 2-week double-blind period. The primary efficacy endpoint was the proportion of all treated attacks that achieved pain-free status within 15 minutes after treatment initiation, without rescue treatment. Results The Full Analysis Set comprised 48 nVNS-treated (14 eCH, 34 cCH) and 44 sham-treated (13 eCH, 31 cCH) subjects. For the primary endpoint, nVNS (14%) and sham (12%) treatments were not significantly different for the total cohort. In the eCH subgroup, nVNS (48%) was superior to sham (6%; p < 0.01). No significant differences between nVNS (5%) and sham (13%) were seen in the cCH subgroup. Conclusions Combing both eCH and cCH patients, nVNS was no different to sham. For the treatment of CH attacks, nVNS was superior to sham therapy in eCH but not in cCH. These results confirm and extend previous findings regarding the efficacy, safety, and tolerability of nVNS for the acute treatment of eCH.

Societal burden of cluster headache in the United States: a descriptive economic analysis

AIM

To estimate direct and indirect costs in patients with a diagnosis of cluster headache in the US.

METHODS

Adult patients (18-64 years of age) enrolled in the Marketscan Commercial and Medicare Databases with ≥2 non-diagnostic outpatient (≥30 days apart between the two outpatient claims) or ≥1 inpatient diagnoses of cluster headache (ICD-9-CM code 339.00, 339.01, or 339.02) between January 1, 2009 and June 30, 2014, were included in the analyses. Patients had ≥6 months of continuous enrollment with medical and pharmacy coverage before and after the index date (first cluster headache diagnosis). Three outcomes were evaluated: (1) healthcare resource utilization, (2) direct healthcare costs, and (3) indirect costs associated with work days lost due to absenteeism and short-term disability. Direct costs included costs of all-cause and cluster headache-related outpatient, inpatient hospitalization, surgery, and pharmacy claims. Indirect costs were based on an average daily wage, which was estimated from the 2014 US Bureau of Labor Statistics and inflated to 2015 dollars.

RESULTS

There were 9,328 patients with cluster headache claims included in the analysis. Cluster headache-related total direct costs (mean [standard deviation]) were $3,132 [$13,396] per patient per year (PPPY), accounting for 17.8% of the all-cause total direct cost. Cluster headache-related inpatient hospitalizations ($1,604) and pharmacy ($809) together ($2,413) contributed over 75% of the cluster headache-related direct healthcare cost. There were three sub-groups of patients with claims associated with indirect costs that included absenteeism, short-term disability, and absenteeism + short-term disability. Indirect costs PPPY were $4,928 [$4,860] for absenteeism, $803 [$2,621] for short-term disability, and $3,374 [$3,198] for absenteeism + disability.

CONCLUSION

Patients with cluster headache have high healthcare costs that are associated with inpatient admissions and pharmacy fulfillments, and high indirect costs associated with absenteeism and short-term disability.

Diagnosis, pathophysiology, and management of cluster headache

Cluster headache is a trigeminal autonomic cephalalgia characterised by extremely painful, strictly unilateral, short-lasting headache attacks accompanied by ipsilateral autonomic symptoms or the sense of restlessness and agitation, or both. The severity of the disorder has major effects on the patient's quality of life and, in some cases, might lead to suicidal ideation. Cluster headache is now thought to involve a synchronised abnormal activity in the hypothalamus, the trigeminovascular system, and the autonomic nervous system. The hypothalamus appears to play a fundamental role in the generation of a permissive state that allows the initiation of an episode, whereas the attacks are likely to require the involvement of the peripheral nervous system. Triptans are the most effective drugs to treat an acute cluster headache attack. Monoclonal antibodies against calcitonin gene-related peptide, a crucial neurotransmitter of the trigeminal system, are under investigation for the preventive treatment of cluster headache. These studies will increase our understanding of the disorder and perhaps reveal other therapeutic targets.

Clinical Features of Cluster Headache Patients in Korea

Cluster headache (CH) is a rare underdiagnosed primary headache disorder with very severe unilateral pain and autonomic symptoms. Clinical characteristics of Korean patients with CH have not yet been reported. We analyzed the clinical features of CH patients from 11 university hospitals in Korea. Among a total of 200 patients with CH, only 1 patient had chronic CH. The average age of CH patients was 38.1 ± 8.9 years (range 19-60 years) and the average age of onset was 30.7 ± 10.3 years (range 10-57 years). The male-to-female ratio was 7:1 (2.9:1 among teen-onset and 11.7:1 among twenties-onset). Pain was very severe at 9.3 ± 1.0 on the visual analogue scale. The average duration of each attack was 100.6 ± 55.6 minutes and a bout of CH lasted 6.5 ± 4.5 weeks. Autonomic symptoms were present in 93.5% and restlessness or agitation was present in 43.5% of patients. Patients suffered 3.0 ± 3.5 (range 1-25) bouts over 7.3 ± 6.7 (range 1-30) years. Diurnal periodicity and season propensity were present in 68.5% and 44.0% of patients, respectively. There were no sex differences in associated symptoms or diurnal and seasonal periodicity. Korean CH patients had a high male-to-female ratio, relatively short bout duration, and low proportion of chronic CH, unlike CH patients in Western countries.

Prevalence of Cluster Headache in a Population-Based Sample in Germany

A population-based sample of 6000 inhabitants of the city of Essen in Germany was screened using a standard questionnaire for possible cluster headache (CH). Fifty-six percent responded ( N = 3336, 50.5% of them women, mean age 44.7 ± 12.7 years). All suspected cases ( N = 182) were interviewed by a neurologist. Four subjects with CH (three men) were identified. The 1-year prevalence of CH was estimated to be 119/100 000 (95% confidence interval 3, 238/100 000).

[Cluster headache in pediatric population: four case reports and review of the literature]

INTRODUCTION

Cluster headache is a rare cause of primary headache in children. We report four cases with a mean age of onset of 8.6, ranged from 2 to 13 years.

CASE REPORTS

Three males and one female with onset at 2, 7, 13, and 12 years-old, respectively, were included. The symptoms of all patients fulfill the criteria for the diagnosis of cluster headache according to the International Society of Headache.

CONCLUSIONS

Despite being rare during childhood, cluster headache should be part of the differential diagnosis of headache in childhood. This report highlights the variable features of this disorder in children, often misdiagnosed. It can be useful in making a quick diagnosis and starting the appropriate treatment early. Verapamil was more effective than flunarizine in terminating the headache in our patients. Oxygen treatment and triptans resulted the treatments with the best response in acute cluster headache.

Trigeminal Autonomic Cephalgias and Variants: Clinical Profile in Indian Patients

The present study summarizes the authors' experience of the clinical profile of short-lasting trigeminal autonomic cephalgias (TAC) in Indian patients. Over a period of 17 years a total of 41 cases of episodic cluster headache, seven cases of chronic cluster headache, six cases of variant cluster headache, three cases of paroxysomal hemicrania, and a single case of SUNCT syndrome were encountered. TACs appear to be rare in Indian patients and cluster headache seems to be exclusively a disease of men. The present report is to the best of our knowledge the first of its kind to be reported from India.