Evidence-based treatments for cluster headache

Oxygen Therapy in Cluster Headache, Migraine, and Other Headache Disorders

Oxygen therapy (OT) can relieve head pain in certain primary headache disorders, including cluster headache (CH). The exact underlying mechanism is currently uncertain, but suggested mechanisms include inhibition of the trigeminoautonomic reflex, modulation of neurotransmitters, and cerebral vasoconstriction. OT is the standard for acute treatment of CH, but patients with CH often experience considerable difficulties accessing home OT due to problems with insurance coverage. Inhalation of 100% oxygen at 6–12 L/min for 15–30 min using a non-rebreather face mask is one of the most effective acute therapies for CH, but several trials have indicated the superiority of higher oxygen flow rates of up to 15 L/min and/or using a demand-valve oxygen mask that can produce very high flow rates. Two randomized controlled trials have demonstrated the efficacy of OT in migraine, but obtaining reliable evidence is considered difficult because of different inhalation protocols, varying outcome measures, and small samples. There are some reports on the efficacy of OT as an adjuvant therapy in hypnic headache, primary headache in the emergency department, and even postdural puncture headache. The goal of this review article is to expand the knowledge regarding the use of oxygen in the treatment of headache disorders.

Effectiveness of medication in cluster headache

Background

The aim of this work is to analyze the reports on cluster headache attacks collected online in the citizen science project CLUE with respect to the effectiveness of drugs taken during the attacks. The collection of data within the framework of citizen science projects opens up the possibility of investigating the effectiveness of acute medication on the basis of a large number of individual attacks instead of a simple survey of patients.

Methods

Data from 8369 cluster headache attacks, containing information about acute medication taken and the assessment of its effect, were collected from 133 participants using an online platform and a smartphone app. Chi-square tests were used to investigate whether the effect of the three recommended acute drugs differs when distinguishing between participants with chronic or episodic cluster headache. Furthermore, it was investigated whether there are differences between smokers and non-smokers in the assessment of the effect of the acute medication.

Results

Our participants rated the effectiveness of sumatriptan 6 mg s.c. as significantly better than oxygen and zolmitriptan nasal spray. Oxygen is considered to be significantly better in episodic versus chronic cluster headache, and sumatriptan is considered to be significantly better in chronic versus episodic cluster headache. Smokers rate the effect of oxygen as significantly better than non-smokers.

Conclusions

Despite some methodological limitations, web-based data collection is able to support findings from clinical trials in a real world setting about effectiveness of acute cluster headache treatment in several situations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02195-8.

The Efficacy of Sphenopalatine Ganglion Block and Radiofrequency Denervation in the Treatment of Cluster Headache: A Case Series

Background

Cluster headache is a variant of primary neurovascular headaches. some patients with cluster headache are not responsive to medical treatment and may benefit from interventional modalities, including sphenopalatine ganglion block and denervation.

Objectives

Our purpose was to evaluate the efficacy of sphenopalatine ganglion block/denervation in the treatment of cluster headache.

Methods

In this study, we performed the sphenopalatine ganglion block for patients with cluster headaches, intractable to medical therapy, who were referred to our pain clinic between 2014 and 2018. We registered the following information for all patients: demographic data, pain relief, and pain intensity. First, we conducted a prognostic C-arm-guided sphenopalatine ganglion block. If there was at least 50% pain relief within the first 5 h, then we denervated the ganglion by radiofrequency ablation. The main outcome of the study (dependent variable) was pain relief. We followed the patients for 6 months.

Results

Among 23 enrolled patients, 19 consented to interventional treatment. Fifteen out of 19 patients (79%) had an acceptable response to the prognostic block. Ultimately, 11 patients underwent ganglion denervation, and 4 patients did not consent for ganglion ablation. Pain relief at intervals of 48 h, and 1, 3, and 6 months after ganglion denervation was 77, 59, 50, and 31 percent, respectively.

Conclusions

Sphenopalatine ganglion conventional radiofrequency denervation can effectively decrease the pain intensity of the patients with cluster headache for at least several months.

Perceptions, experiences, and understandings of cluster headache among GPs and neurologists: a qualitative study

BACKGROUND

Cluster headache is a severe primary headache with a similar prevalence to that of multiple sclerosis. Cluster headache is characterised by unilateral trigeminal distribution of pain, ipsilateral cranial autonomic features, and a tendency to circadian and circannual periodicity.

AIM

To explore the perceptions, experiences, and understandings of cluster headache among GPs and neurologists.

DESIGN AND SETTING

Qualitative interview study in primary care surgeries and neurology departments in the north of England.

METHOD

Semi-structured interviews were conducted with GPs and neurologists, recorded, and transcribed. A thematic analysis was applied to the dataset.

RESULTS

Sixteen clinicians participated in this study: eight GPs and eight neurologists. Four main themes were identified following thematic analysis: challenges with the cluster headache diagnosis; impact of cluster headache; challenges with treatment; and appropriateness of referrals to secondary care. Clinicians recognised the delays in the diagnosis of cluster headache, misdiagnosis, and mismanagement, and were aware of the potential impact cluster headache can have on patients' mental health and ability to remain in employment. Findings highlighted tensions between primary and secondary care around the cost of medication and the remit of prescribing treatment regimens. Patients' anxiety, their need for reassurance, and their insistence about seeing a specialist are some of the reasons for referrals.

CONCLUSION

Clinicians acknowledged delays in diagnosis, misdiagnosis, and mismanagement of cluster headache. The responsibility of prescribing causes ongoing tensions between primary and secondary care. Clear referral and management pathways for primary headaches are required to improve patient outcomes and healthcare costs.

Percutaneous Bioelectric Current Stimulation for Chronic Cluster Headache - A Possible Transformative Approach to Cluster Headache

Background

Cluster headache (CH) is considered to be a catastrophic disease presenting the most severe human pain condition. Available pharmacological treatments are hampered by unwanted side effects, and there is an urgent need for non-pharmacological treatment alternatives. We present a novel therapeutic approach for chronic CH, having evolved from an episodic CH, using a non-invasive percutaneous bioelectric current stimulation (PBCS), which generates static electric fields in the range of the naturally occurring electric potentials.

Patients and Methods

This study employed a retrospective data analysis of 20 cases of chronic cluster headache (CCH) patients, four of those having had cluster-related surgery (SPG, ONS). All patients were treated with PBCS between 2014 and 2018. Data of these patients were analyzed with respect to frequency of CH attacks and triptan application and followed up for one (20 cases) or two (12 cases) years.

Results

Four weeks after the first PBCS treatment, cluster headache attacks were reduced from 2.8 to 1.7 per day and triptan application decreased from 2.5 to 1.5 times/day. Six non-responders, 4 of which had pre-CH surgery, did not show any reaction to PBCS, while 14 responders improved within 4 weeks from 2.2 to 0.7 attacks/day and 2.0 to 0.4 triptan applications/day. A 50% or greater reduction of attack frequency was observed in 10 patients after 4 weeks and in 11 patients after 12 weeks. One year after the first treatment, 13/20 patients experienced a reduction of attack frequency of 50% or more, while remarkably 10 patients were completely free of attack. After 2 years, 8 of 12 patients experienced a reduction of attack frequency of 50% or more and 7 of those were completely symptom-free. No serious adverse effects were observed.

Conclusion

PBCS is a promising transformative treatment approach for CCH patients. Drug consumption was reduced significantly, and the CCH may revert back to an episodic cluster headache with increasingly long times of remission. Responders can be clearly differentiated from non-responders. The data support the need for randomized controlled trials.

Development and Evaluation of a Screening Tool to Aid the Diagnosis of a Cluster Headache

Cluster headache (CH), a severe primary headache, is often misdiagnosed and mismanaged. The aim of this study was to develop and evaluate a screening tool to aid the diagnosis of CH. We developed a novel 12-item screening tool. This was comprised of four components: (1) images depicting headache pain; (2) pain descriptors; (3) key questions that could differentiate between CH and migraine; and (4) a visual analogue pain scale. The total possible questionnaire score ranged from 3-32. Patients with CH and migraines (control group) were recruited prospectively from a headache centre in the North of England, UK. Two-hundred and ninety-six patients were included in the study: 81 CH patients, 36 of which suffer with episodic CH and 45 with chronic CH; 215 migraine patients, 92 of which suffer with episodic migraine and 123 with chronic migraine. The mean questionnaire score was higher in CH patients versus migraine patients (28.4 versus 19.5). At a cut-off score of >25 out of 32, the screening tool had a sensitivity of 86.4% and a specificity of 92.0% in differentiating between CH and migraine. The screening tool could be a useful instrument to aid the diagnosis of a CH. The images depicting headache pain do not clearly discriminate between CH and migraine.

Occipital nerve stimulation and deep brain stimulation for refractory cluster headache: a prospective analysis of efficacy over time

OBJECTIVE

Occipital nerve stimulation (ONS) and deep brain stimulation (DBS) are widely used surgical treatments for chronic refractory cluster headache (CH). However, there is little literature regarding long-term follow-up of these treatments.

METHODS

The authors describe two prospective cohorts of patients with refractory CH treated with ONS and DBS and compare preoperative to postoperative status at 6 and 12 months after the surgery and at final follow-up. Efficacy analysis using objective and subjective variables is reported, as well as medication reduction and complications.

RESULTS

The ONS group consisted of 13 men and 4 women, with a median age of 44 years (range 31-61 years). The median number of attacks per week (NAw) before surgery was 28 (range 7-70), and the median follow-up duration was 48 months. The DBS group comprised 5 men and 2 women, with a median age of 50 years (range 29-64 years). The median NAw before surgery was 56 (range 14-140), and the median follow-up was 36 months. The NAw and visual analog scale score were significantly reduced for the ONS and DBS groups after surgery. However, while all the patients from the DBS group were considered responders at final follow-up, with more than 85% being satisfied with the treatment, approximately 29% of initial responders to ONS became resistant by the final follow-up (p = 0.0253).

CONCLUSIONS

ONS is initially effective as a treatment for refractory CH, although a trend toward loss of efficacy was observed. No clear predictors of good clinical response were found in the present study. Conversely, DBS appears to be effective and provide a more stable clinical response over time with an acceptable rate of surgical complications.

Images depicting headache pain - a tool to aid the diagnosis of cluster headache: a pilot study

Introduction and objective

The diagnosis of primary headaches is based on the International Classification of Headache Disorders (ICHD-3). Cluster headache (CH), a debilitating primary headache, is often misdiagnosed as migraine. In the absence of biological markers, a new visual screening tool with images depicting pain could aid the correct diagnosis of CH. The objective of the study is to test the tool on healthy participants and participants with CH and migraine.

Methods

In phase 1, 6 images portraying people with pain were tested on 150 healthy participants. The healthy participants were asked to rate the images as mild, moderate, severe or excruciating pain. In phase 2, the images were further tested on 116 participants with headache (16 participants with CH, 100 participants with migraine). The participants were recruited prospectively from a tertiary headache center between February and May 2017. The participants were asked to choose which image best illustrated their headache attacks.

Results

Phase 1 results showed that the images represent a range of headache pain severities from mild to excruciating as rated by healthy participants. They rated two images as excruciating, one image as severe, one image as moderate/severe, one image as moderate and one image as mild. Phase 2 results showed that two-thirds of participants with CH (69%) and half of the participants with migraine (52%) chose an image described as excruciating by the healthy participants.

Conclusion

We developed a screening tool with six drawings depicting headache pain severities from mild to excruciating as rated by the healthy participants. Although the images did not differentiate between CH and migraine, the study indicated the potential of using visual aids to assess headache severity.

Extracranial Trigger Site Surgery for Migraine: A Systematic Review With Meta-Analysis on Elimination of Headache Symptoms

Introduction: The headache phase of migraine could in selected cases potentially be treated by surgical decompression of one or more “trigger sites,” located at frontal, temporal, nasal, and occipital sites. This systematic review with subsequent meta-analysis aims at critically evaluating the currently available evidence for the surgical treatment of migraine headache and to determine the effect size of this treatment in a specific patient population.

Methods: This study was conducted following the PRISMA guidelines. An online database search was performed. Inclusion was based on studies published between 2000 and March 2018, containing a diagnosis of migraine in compliance with the classification of the International Headache Society. The treatment must consist of one or more surgical procedures involving the extracranial nerves and/or arteries with outcome data available at minimum 6 months.

Results: Eight hundred and forty-seven records were identified after duplicates were removed, 44 full text articles were assessed and 14 records were selected for inclusion. A total number of 627 patients were included in the analysis. A proportion of 0.38 of patients (random effects model, 95% CI [0.30–0.46]) experienced elimination of migraine headaches at 6–12 months follow-up. Using data from three randomized controlled trials, the calculated odds ratio for 90–100% elimination of migraine headaches is 21.46 (random effects model, 95% CI [5.64–81.58]) for patients receiving migraine surgery compared to sham or no surgery.

Conclusions: Migraine surgery leads to elimination of migraine headaches in 38% of the migraine patients included in this review. However, more elaborate randomized trials are needed with transparent reporting of patient selection, medication use, and surgical procedures and implementing detailed and longer follow-up times.

Cluster headache - clinical pattern and a new severity scale in a Swedish cohort

Background The aim of this study was to investigate clinical features of a cluster headache cohort in Sweden and to construct and test a new scale for grading severity. Methods Subjects were identified by screening medical records for the ICD 10 code G44.0, that is, cluster headache. Five hundred participating research subjects filled in a questionnaire including personal, demographic and medical aspects. We constructed a novel scale for grading cluster headache in this cohort: The Cluster Headache Severity Scale, which included number of attacks per day, attack and period duration. The lowest total score was three and the highest 12, and we used the Cluster Headache Severity Scale to grade subjects suffering from cluster headache. We further implemented the scale by defining a cluster headache maximum severity subgroup with a high Cluster Headache Severity Scale score ≥ 9. Results A majority (66.7%) of the patients reported that attacks appear at certain time intervals. In addition, cluster headache patients who were current tobacco users or had a history of tobacco consumption had a later age of disease onset (31.7 years) compared to non-tobacco users (28.5 years). The Cluster Headache Severity Scale score was higher in the patient group reporting sporadic or no alcohol intake than in the groups reporting an alcohol consumption of three to four standard units per week or more. Maximum severity cluster headache patients were characterised by higher age at disease onset, greater use of prophylactic medication, reduced hours of sleep, and lower alcohol consumption compared to the non-cluster headache maximum severity group. Conclusion There was a wide variation of severity grade among cluster headache patients, with a very marked impact on daily living for the most profoundly affected.

Psychoactive substances as a last resort-a qualitative study of self-treatment of migraine and cluster headaches

BACKGROUND

Treatment resistant cluster headache and migraine patients are exploring alternative treatments online. The aim of this study was to improve comprehension regarding the use of non-established or alternative pharmacological treatments used by sufferers of cluster headaches and migraines.

METHODS

A qualitative thematic analysis of the users' own accounts presented in online forum discussions were conducted. The forum boards https://shroomery.org/ , http://bluelight.org , and https://clusterbusters.org/ met the inclusion criteria and were used for the study.

RESULTS

The analysis resulted in six themes: a desperate need for effective treatments; the role of the forum-finding alternative treatments and community support; alternative treatment substances; dosage and regimens; effects and treatment results; and adverse effects. The results provide an insight into why, how, and by which substances and methods sufferers seek relief from cluster headache and migraines.

CONCLUSIONS

These patients are in a desperate and vulnerable situation, and illicit psychoactive substances are often considered a last resort. There appeared to be little or no interest in psychoactive effects per se as these were rather tolerated or avoided by using sub-psychoactive doses. Primarily, psilocybin, lysergic acid diethylamide, and related psychedelic tryptamines were reportedly effective for both prophylactic and acute treatment of cluster headache and migraines. Treatment results with cannabis were more unpredictable. No severe adverse events were reported, but it was observed how desperation sometimes spurred risky behavior when obtaining and testing various treatment alternatives. The forum discourse mainly revolved around maximizing treatment results and minimizing potential harms.

Chronic Cluster Headache with an Atypical Presentation and Treatment Response

The management of cluster headache (CH) may be challenging. We report a 50-year-old male with recurrent attacks of dull and severe unilateral periorbital pain, lasting 30–45 minutes, twice a day, exclusively during sleep, and accompanied by ipsilateral rhinorrhea and lacrimation. The pain switched sides within every attack. CH treatment was initiated but the patient maintained recurrence rates compatible with chronic CH, even after increasing verapamil to 460 mg/day. Afterwards we decided to add lithium (800 mg/day). With this treatment the severity and recurrence of CH substantially decreased, despite the patient's autonomous decision to take lithium only during the acute phase of the cluster. The exclusively alternating location and the excellent response to short cycles of lithium represent two unique features of CH.