Epidemiology of cluster headache

Anatomy and Physiology of Headache

Headache disorders can produce recurrent, incapacitating pain. Migraine and cluster headache are notable for their ability to produce significant disability. The anatomy and physiology of headache disorders is fundamental to evolving treatment approaches and research priorities. Key concepts in headache mechanisms include activation and sensitization of trigeminovascular, brainstem, thalamic, and hypothalamic neurons; modulation of cortical brain regions; and activation of descending pain circuits. This review will examine the relevant anatomy of the trigeminal, brainstem, subcortical, and cortical brain regions and concepts related to the pathophysiology of migraine and cluster headache disorders.

Is conventional brain MRI useful for the diagnosis of cluster headache in patients who meet ICHD-3 criteria? Experience in three hospitals in Spain

OBJECTIVE

To assess the frequency of symptomatic structural lesions and the diagnostic yield of conventional brain MRI in cluster headache (CH).

BACKGROUND

In contrast to migraine, brain MRI is recommended in patients with CH to exclude potential mimics. The prevalence of symptomatic CH is not known.

METHODS

We retrospectively analysed in detail the brain MRIs of patients diagnosed as CH in 3 Neurology Services in Spain and reviewed their clinical history. Clinical diagnoses were reassessed based on the ICHD-3 criteria.

RESULTS

We included 130 patients: 113 (86.9%) were male; mean age at diagnosis being 41.4 years (range 7-82). Forty-nine (37.7%) showed some abnormal MRI finding. Only in two cases potential symptomatic lesions were found: one trigeminal schwannoma and one craneopharyngioma, but both presented atypical features (facial hypoesthesia on examination and episodes of prolonged duration that had progressed to continuous refractory pain without specific pattern, respectively) and therefore did not fulfil the ICHD-3 CH criteria. The remaining abnormal MRI findings were: white matter lesions (24 patients; 18.4%), sinus inflammatory changes (13; 10.0%), small arachnoid cysts (5; 3.8%), empty sella turca (3; 2.3%), and other unspecific findings (8; 6.2%). All of them were not symptomatic based on neuroimaging characteristics, clinical course and response to treatment.

CONCLUSIONS

Brain MRI in patients who meet ICHD-3 CH criteria, with no atypical clinical features, does not show any clinically-relevant findings, suggesting that these criteria are highly predictive of its primary origin and that systematic MRI is not useful for the diagnosis of typical CH.

Neurovascular mechanisms of migraine and cluster headache

Vascular theories of migraine and cluster headache have dominated for many years the pathobiological concept of these disorders. This view is supported by observations that trigeminal activation induces a vascular response and that several vasodilating molecules trigger acute attacks of migraine and cluster headache in susceptible individuals. Over the past 30 years, this rationale has been questioned as it became clear that the actions of some of these molecules, in particular, calcitonin gene-related peptide and pituitary adenylate cyclase-activating peptide, extend far beyond the vasoactive effects, as they possess the ability to modulate nociceptive neuronal activity in several key regions of the trigeminovascular system. These findings have shifted our understanding of these disorders to a primarily neuronal origin with the vascular manifestations being the consequence rather than the origin of trigeminal activation. Nevertheless, the neurovascular component, or coupling, seems to be far more complex than initially thought, being involved in several accompanying features. The review will discuss in detail the anatomical basis and the functional role of the neurovascular mechanisms relevant to migraine and cluster headache.

Clinical Characteristics and Treatment Patterns Among Patients Diagnosed With Cluster Headache in U.S. Healthcare Claims Data

OBJECTIVE

To characterize demographics, clinical characteristics, and treatment patterns of patients with cluster headache (CH).

BACKGROUND

CH is an uncommon trigeminal autonomic cephalalgia with limited evidence-based treatment options. Patients suffer from extremely painful unilateral headache attacks and autonomic symptoms with episodic and chronic cycles.

DESIGN/METHODS

This retrospective analysis used insurance claims from Truven Health Analytics MarketScan® research databases from 2009 to 2014. Two cohorts were compared: CH patients (with ≥2 CH claims) were propensity score matched with 4 non-headache controls, all with continuous enrollment for 12 months before and after the date of first CH claim or matched period among controls.

RESULTS

CH patients (N = 7589) were mainly male (57.4%) and 35-64 years old (73.2%), with significantly more claims for comorbid conditions vs controls (N = 30,341), including depressive disorders (19.8% vs 10.0%), sleep disturbances (19.7% vs 9.1%), anxiety disorders (19.2% vs 8.7%), and tobacco use disorders (12.8% vs 5.3%), with 2.5 times greater odds of suicidal ideation (all P < .0001). Odds of drug dependence were 3-fold greater among CH patients (OR = 2.8 [95% CI 2.3-3.4, P < .0001]). CH patients reported significantly greater use of prescription medications compared with controls; 25% of CH patients had >12 unique prescription drug claims. Most commonly prescribed drug classes for CH patients included: opiate agonists (41%), corticosteroids (34%), 5HT-1 agonists (32%), antidepressants (31%), NSAIDs (29%), anticonvulsants (28%), calcium antagonists (27%), and benzodiazepines (22%). Only 30.4% of CH patients received recognized CH treatments without opioids during the 12-month post-index period. These patients were less likely to visit emergency departments or need hospitalizations (26.8%) as compared to CH patients with no pharmacy claims for recognized CH treatments or opioids (33.6%; P < .0001).

CONCLUSIONS

The burden of CH is associated with significant co-morbidity, including substance use disorders and suicidal ideation, and treatment patterns indicating low use of recognized CH treatments.

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.

The Frequent Unusual Headache Syndromes: A Proposed Classification Based on Lifetime Prevalence

BACKGROUND

There is no agreement on a single cutoff point or prevalence for regarding a given disease as rare. The concept of what is a rare headache disorder is even less clear and the spectrum from a very frequent, frequent, occasional to rare headache syndrome is yet to be established.

OBJECTIVE

An attempt has been made to estimate the lifetime prevalence of each of the headache subtypes classified in the ICHD-II.

METHOD

Using the ICHD-II, 199 different headache subtypes were identified. The following classification was made according to the estimated lifetime prevalence of each headache disorder: very frequent (prevalence >10%); frequent (between 1 and 10%); occasional (between 0.07 and 1%); and unusual or rare (<0.07%).

RESULTS

One hundred and fifty-four of 199 (77%) were categorized as unusual headache disorders, 7/199 (4%) as very frequent, 9/199 (5%) as frequent, and 29/199 (15%) as occasional forms of headache disorder.

CONCLUSION

The unusual headache syndromes do not appear to be as infrequent in clinical practice as has been generally believed. About three-fourths of the classified headache disorders found in the ICHD-II can be considered as rare. This narrative review article may be regarded as an introduction to the concept of unusual headaches and a proposed classification of all headaches (at least those listed in the ICHD-II).

WITHDRAWN: Dipyrone for acute primary headaches

The original authors of this review are unable to update it. The Cochrane Pain, Palliative and Supportive Care Review Group (PaPaS) is seeking new authors to update and split the review into two separate reviews on migraine and tension‐type headache. If you are interested, please contact the Managing Editor of PaPaS (contact details provided under 'Contact Person').

At July 2014, this review has been withdrawn. This review is out of date although it is correct as of the date of publication. The latest version is available in the ‘Other versions’ tab on The Cochrane Library, and may still be useful to readers.

The editorial group responsible for this previously published document have withdrawn it from publication.

Impact of continuing or quitting smoking on episodic cluster headache: a pilot survey

BACKGROUND

The majority of patients suffering from cluster headache (CH) are smokers and it has been suggested that smoking may trigger the development of CH. The aim of this pilot survey was to describe: 1. the differences between current, former, and never smokers CH patients; 2. if smoking changed during an active cluster period; 3. if CH changed after quitting.

METHODS

All outpatients with episodic CH according to the criteria of ICHD-II who were consecutively seen for the first time from October 2010 to April 2012 at a headache centre were interviewed by phone using a specifically prepared questionnaire. Statistical differences between continuous variables were analysed by the Student's t-test or the one-way analysis of variance (ANOVA), followed by Newman-Keuls post-hoc testing. Comparisons between percentages were made using the Chi-square test or Fisher's exact test. All data were expressed as the mean ± standard deviation (SD).

RESULTS

Among a total of 200 patients surveyed (172 males, 28 females; mean age ± SD: 48.41 ± 12 years) there were 60%, 21%, and 19% of current, former, and never smokers, respectively. Current smokers reported longer active periods (12.38 ± 10 weeks) and a higher maximum number of attacks per day (3.38 ± 1) compared to never smoker CH patients (5.68 ± 4 weeks, P <0.05 and 2.47 ± 1, P <0.05, respectively). During the active period most of the patients stated to decrease (45.7%) or not to change (45.7%) the number of cigarettes smoked. Among those who decreased smoking, most (83.8%) reported that they had less desire to smoke. After quitting, the majority of former smokers stated that their headache had not changed.

CONCLUSIONS

Patients with episodic CH who are also smokers appear to have a more severe form of the disorder. However, it is unlikely that between CH and smoking there is a causal relationship, as CH patients rarely improve quitting smoking.

Trigeminal autonomic cephalalgias. Part 1: cluster headache

Cluster headache is characterized by severe, strictly unilateral pain attacks lasting 15 to 180 minutes localized to orbital, temporal, and midface areas accompanied by ipsilateral autonomic features. It represents 1 of 3 primary headaches classified as trigeminal autonomic cephalalgias. While its prevalence is small, it is not uncommon for cluster headache patients to present at dental offices seeking relief for their pain. It is important for oral health care providers to recognize cluster headache and render an accurate diagnosis. This will avoid the pitfall of implementing unnecessary and inappropriate traditional dental treatments in hopes of alleviating this neurovascular pain. The following article is part 1 of a review on trigeminal autonomic cephalalgias and focuses on cluster headache. Aspects of cluster headache including its prevalence and incidence, genetics, pathophysiology, clinical presentation, classification and variants, diagnosis, medical management, and dental considerations are discussed.

Dipyrone for acute primary headaches

BACKGROUND

Dipyrone is used to treat headaches in many countries, but is not available in others (particularly the USA and UK) because of its association with potentially life-threatening blood dyscrasias such as agranulocytosis.

OBJECTIVES

To determine the effectiveness and safety of dipyrone for acute primary headaches in adults and children.

SEARCH STRATEGY

We searched the Cochrane Pain, Palliative & Supportive Care Group's Trials Register; the Cochrane Central Register of Controlled Trials; MEDLINE; EMBASE; LILACS, and the reference lists of included studies.

SELECTION CRITERIA

Double-blind randomised controlled trials of dipyrone for the symptomatic relief of acute primary headaches in adults and children.

DATA COLLECTION AND ANALYSIS

Three authors independently screened articles, extracted data, assessed trial quality and analysed results. Relative risks (RRs), risk differences (RDs), weighted mean differences (WMDs), and numbers-needed-to-treat (NNTs) were calculated as appropriate.

MAIN RESULTS

Four trials involving a total of 636 adult subjects were included. Methodological quality was generally high. One study each evaluated oral and intravenous dipyrone for episodic tension-type headache (ETTH); two trials evaluated intravenous dipyrone for migraine, but only one of these described pain outcomes. No pediatric trials were identified. The largest trial (n = 356) evaluated two doses (0.5 g, 1 g) of oral dipyrone for ETTH, which were significantly better than placebo for pain relief. The 1 g dose was also significantly better than acetylsalicylic acid (ASA) 1 g . A smaller trial (n = 60) evaluated intravenous dipyrone 1 g versus placebo for ETTH. RRs were statistically significant favouring dipyrone for pain-free and headache improvement outcomes. Finally, one trial (n = 134) evaluated intravenous dipyrone 1 g versus placebo for pain outcomes in patients with migraine. RRs were again statistically significant favouring dipyrone for pain-free and headache improvement outcomes. Two of the four trials assessed adverse events. No serious adverse events were reported, and no significant differences in adverse events were detected between dipyrone and comparators (placebo and ASA).

AUTHORS' CONCLUSIONS

Evidence from a small number of trials suggests that dipyrone is effective for ETTH and migraine. No serious adverse events were observed in the included trials, but agranulocytosis is rare and would probably not be observed in such a relatively small sample. A study now ongoing in Latin America may clarify the true risk of agranulocytosis associated with dipyrone use.

Pharmacokinetics and interactions of headache medications, part I: introduction, pharmacokinetics, metabolism and acute treatments

Recent progress in the treatment of primary headaches has made available specific, effective and safe medications for these disorders, which are widely spread among the general population. One of the negative consequences of this undoubtedly positive progress is the risk of drug-drug interactions. This review is the first in a two-part series on pharmacokinetic drug-drug interactions of headache medications. Part I addresses acute treatments. Part II focuses on prophylactic treatments. The overall aim of this series is to increase the awareness of physicians, either primary care providers or specialists, regarding this topic. Pharmacokinetic drug-drug interactions of major severity involving acute medications are a minority among those reported in literature. The main drug combinations to avoid are: i) NSAIDs plus drugs with a narrow therapeutic range (i.e., digoxin, methotrexate, etc.); ii) sumatriptan, rizatriptan or zolmitriptan plus monoamine oxidase inhibitors; iii) substrates and inhibitors of CYP2D6 (i.e., chlorpromazine, metoclopramide, etc.) and -3A4 (i.e., ergot derivatives, eletriptan, etc.), as well as other substrates or inhibitors of the same CYP isoenzymes. The risk of having clinically significant pharmacokinetic drug-drug interactions seems to be limited in patients with low frequency headaches, but could be higher in chronic headache sufferers with medication overuse.

Headache prevalence related to smoking and alcohol use. The Head-HUNT Study

The aim of this study was to examine a possible association between smoking, alcohol and headache in a large population-based cross-sectional study. A total of 51,383 subjects completed a headache questionnaire and constituted the 'Head-HUNT' Study. Questionnaire-based information on smoking was available in 95% and on alcohol in 89% of the individuals. Associations were assessed in multivariate analyses, estimating prevalence odds ratios (ORs) with 95% confidence intervals (CI). Prevalence rates for headache were higher amongst smokers compared with never smokers, most evident for those under 40 years smoking more than 10 cigarettes per day (OR 1.5, 95% CI 1.3-1.6). Passive smoking was also associated with higher headache prevalence. For alcohol use, there was a tendency of decreasing prevalence of migraine with increasing amounts of alcohol consumption compared with alcohol abstinence. Only with regard to symptoms indicating alcohol overuse, a positive association with frequent headache was found. The association between headache and smoking found in the present study raises questions about a causal relationship, e.g. that smoking causes headache or that it allays stress induced by headache. The observed negative association between migraine and alcohol consumption is probably explained by the headache precipitating properties of alcohol.

Cluster headache and the heart

Cluster headache is a rare but debilitating recurrent headache disorder. It is most common in middle-aged and older men, a group with a high prevalence of cardiovascular disease. This article reviews available information regarding the association of cluster headache and the heart in three selected areas: 1) the known effects of cluster headache on cardiovascular parameters such as heart rate and rhythm and blood pressure; 2) the prevalence of cardiac risk factors in subjects with cluster headache; and 3) the connection between patent foramen ovale and cluster headache. Some evidence suggests that cardiovascular risk factors, especially cigarette smoking, may be more common in cluster headache sufferers. There also is evidence that disturbances of autonomic function or certain structural cardiac anomalies may be more common in cluster headache sufferers. In addition, a number of important treatment options for cluster headache have effects on cardiovascular function that must be considered in planning therapy. The implications of these findings for clinical practice are discussed.

Cluster headache pharmacotherapy

Cluster headache is a well-known primary headache syndrome with a prevalence of about 5/10,000 of the adult population, making it much less common than migraine. Diagnostic terms such as histaminic cephalalgia, Horton's headache and ciliary neuralgia have been used for what is now known as cluster headache. This disorder can be differentiated from migraine by clinical and pathophysiologic features. Cluster headache also exhibits a differing therapeutic response to medications when compared with migraine. The pharmacologic treatment of cluster is reviewed in this article. In contrast to migraine, men are 3-4 times more likely to be diagnosed with cluster headache than women, and the cluster headache population is older. Cluster attacks are known for their brief intense unilateral excruciating pain during susceptible periods known as cluster periods, which typically last weeks. Attack-free months generally follow. Pain is experienced in the distribution of the trigeminal nerve, with unilateral autonomic features. Most patients are successfully managed with medical therapy. Medication management can be divided into abortive treatments for an ongoing attack and prophylactic treatment. Prophylaxis aims to induce and maintain a remission. There are a variety of different medications for abortive and prophylactic therapy, accompanied by a variable amount of evidence-based medicine. For patients refractory to medical management, interventional procedures are available as a last resort. Most procedures are directed against the sensory trigeminal nerve and associated ganglia, eg, anesthetizing the sphenopalatine ganglion.

Orofacial Pain--Part II: Assessment and management of vascular, neurovascular, idiopathic, secondary, and psychogenic causes

Chronic orofacial pain is a common health complaint faced by health practitioners today and constitutes a challenging diagnostic problem that often requires a multidisciplinary approach to diagnosis and treatment. The previous article by the same authors in this issue discussed the major clinical characteristics and the treatment of various musculoskeletal and neuropathic orofacial pain conditions. This second article presents aspects of vascular, neurovascular, and idiopathic orofacial pain, as well as orofacial pain due to various local, distant, or systemic diseases and psychogenic orofacial pain. The emphasis in this article is on the general differential diagnosis and various therapeutic regimens of each of these conditions. An accurate diagnosis is the key to successful treatment of chronic orofacial pain. Given that for many of the entities discussed in this article no curative treatment is available, current standards of management are emphasized. A comprehensive reference section has been included for those who wish to gain further information on a particular entity.

Etiology of primary headaches: the importance of genes and environment

Results from twin studies show that genes play an important role for susceptibility to migraine. The propensity for migraine to run in some families but not in others arises predominantly from alleles shared by family members and not the shared family environment, and that environmental influences on migraine are unique to the affected family member. The main genetic and environmental architecture for the other two major primary headaches, tension-type and cluster, remains to be elucidated. This review focuses on recent advances in twin studies of primary headaches and the future prospects are outlined.

Rare nocturnal headaches

PURPOSE OF REVIEW

This review describes rare headaches that can occur at night or during sleep, with a focus on cluster headaches, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing, hypnic headache and exploding head syndrome.

RECENT FINDINGS

It is known that cluster headaches and hypnic headache are associated with rapid eye movement sleep, as illustrated by recent polysomnographic studies. Functional imaging studies have documented hypothalamic activation that is likely to be of relevance to circadian rhythms. These headache syndromes have been shown to respond to melatonin and lithium therapy, both of which have an indirect impact on the sleep-wake cycle.

SUMMARY

There is growing evidence that cluster headache and hypnic headache are chronobiological disorders.