Sleep apnea in cluster headache

The objective assessment of sleep in cluster headache: State of the art and future directions

Several lines of evidence suggest that cluster headache is related to chronobiology and sleep. Nevertheless, the nature of such a relationship is unclear. In this view, the objective evaluation of sleep in cluster headache has strong theoretical and clinical relevance. Here, we provide an in-depth narrative review of the literature on objective sleep assessment in cluster headache. We found that only a small number of studies (N = 12) focused on this topic. The key research aims were directed to assess: (a) the relationship between cluster headache and sleep breathing disorders; (b) the temporal relationship between sleep stages/events and cluster headache attacks; (c) sleep macrostructure in patients with cluster headache. No studies considered sleep microstructure. The reviewed studies are heterogeneous, conducted by a few research groups, and often characterised by relevant methodological flaws. Results are substantially inconclusive considering the main hypothesis. We outline several methodological points that should be considered for future research, and suggest that evaluating sleep microstructure, local sleep electrophysiology and actigraphic measures may strongly increase knowledge on the relationship between sleep and cluster headache.

Continuous positive airway pressure in cluster headache: A randomized, placebo-controlled, triple-blind, crossover study

BACKGROUND

Oxygen inhalation aborts cluster headache attacks, and case reports show the effect of continuous positive airway pressure. The aim of this study was to investigate the prophylactic effect of continuous positive airway pressure in chronic cluster headache.

METHODS

This was a randomized placebo-controlled triple-blind crossover study using active and sham continuous positive airway pressure treatment for chronic cluster headache. Patients entered a one month's baseline period before randomly being assigned to two months' active continuous positive airway pressure treatment followed by a four weeks' washout period and two months' sham continuous positive airway pressure or vice versa. Primary outcome measure was number of cluster headache attacks/week.

RESULTS

Of the 30 included participants (12 males, median age 49.5 years, min-max 20-66 years), 25 completed both treatment/sham cycles (two discontinued, three lost to follow-up). The median number of cluster headache attacks per week was reduced from 8.25 (0.75-89.75) attacks to 6.25 (0-56.00) attacks for active continuous positive airway pressure and to 7.50 (0.50-43.75) attacks for sham continuous positive airway pressure, but there was no difference in active versus sham (p = 0.904). One patient had a serious adverse event during active treatment, none occurred during sham treatment.

CONCLUSIONS

Continuous positive airway pressure treatment did not reduce the number of cluster headache attacks compared to sham treatment in chronic cluster headache patients.

TRIAL REGISTRATION CLINICALTRIALS.GOV

NCT03397563.

Headache and Sleep Disturbances in the Pediatric Population

The relationship between sleep disturbances and headaches in the pediatric population is bidirectional. Common underlying molecular mechanisms of sleep and headaches have been speculated to explain the clinical connection. We will summarize various sleep disturbances and their known relationships to headache, focusing on the pediatric population. Careful recognition and assessment of sleep disturbances in patients with headache is critical and may help guide treatment. First line therapies for sleep disturbances consist of behavioral approaches, though surgical and pharmacologic strategies are utilized in particular circumstances.

Cluster Headache: A Review and Update in Treatment

PURPOSE OF REVIEW

The treatment of cluster headache has evolved to include a handheld neuromodulation device and a monoclonal antibody in addition to more traditional agents.

RECENT FINDINGS

Galcanezumab is an approved treatment for episodic cluster headache. The non-invasive vagal nerve stimulator has been shown to be effective as a treatment for episodic cluster headache. Dedicated pituitary imaging may not be necessary with a normal MRI of the brain. Cluster headache is the most common trigeminal-autonomic cephalalgia, characterized by unilateral, frequent, debilitating attacks associated with ipsilateral autonomic symptoms. Attacks have a circadian and, often, seasonal pattern with periods of remission that can last months to years in episodic patients. Though a rare disease, an increasing number of studies have revealed novel targets for treatment. Treatment in cluster headache should focus on early intervention to reduce frequency of attacks and the length of the cycle, which improves outcomes and disability. Acute therapy is used to treat attacks, while bridging and preventive therapies are combined to reduce cycle length. Case 1: A 43-year-old man presents with the chief complaint of severe headaches. Upon general examination, he seems uncomfortable, agitated, and exhausted. He states that he hasn't "slept in over a week because of debilitating headaches." His headaches start around the same time every night: when he lays down to go to sleep. The pain is described as sharp, like a "hot poker" to his left eye. His partner has noticed that his eye droops and turns red when the pain starts. The attacks come on abruptly and prevent him from sleeping. The severe pain lasts 30 to 45 min, but he has mild-to-moderate pain that lingers for the rest of the night. He has seen his primary care physician, an allergist, and an ear, nose, and throat (ENT) specialist before coming to see a neurologist. Similar headaches occurred last year during the month of October as well. On further questioning, he reports that these headache attacks have been occurring almost yearly for the past 7 years. Each year, these headaches come on as the weather is changing and occur on a nightly basis for about 3 to 4 weeks.

Current Understanding of the Chronobiology of Cluster Headache and the Role of Sleep in Its Management

Cluster headache is uniquely rhythmic in its occurrence both diurnally and annually. This has implications for the clinical approach to the patient but also for our understanding of the role of central structures in its pathological basis. Many intrinsic and extrinsic factors seem to influence CH rhythmicity, including genetics. The proclivity for attacks to occur at night and the possible association with particular sleep phenomena, including sleep apnea, have motivated a number of studies which has improved our understanding but many questions remain unanswered. The sleep-headache interaction seems to be bidirectional and possibly both direct and indirect. The latter could involve more disperse networks of homeostatic regulation, which may better encompass recent observations. Treatment of the headache patient with concurrent sleep problems can be particularly challenging, especially considering side-effects and interactions of commonly used medications. While current treatment guidelines do not incorporate chronotherapeutic thinking, some evidence may suggest that application of such principles on an individual level may be beneficial.

Exploring the Connection Between Sleep and Cluster Headache: A Narrative Review

Cluster headache is a rare form of headache associated with sleep and even speculated to be a manifestation of a sleep disorder rather than a primary headache. Cluster headache exhibits both circadian and circannual rhythmicity. While attacks often occur during sleep, the implication that cluster headaches might be involved with rapid eye movement (REM) sleep phases has neither been fully established nor refuted. The regulatory mechanisms governing sleep including hypothalamic activity and the autonomic nervous system response may play a role. Hypothalamic activation has been observed in cluster headache patients during positron emission tomography testing, but only during attacks. While sleep apnea is associated with morning headaches in general, the link between sleep-disordered respiration and cluster headache remains elusive. Hypoarousal during sleep and periods of hypoxia are associated with cluster headache, the latter likely involving inflammatory processes rather than apnea. Further study is needed, as cluster headaches represent a serious primary cephalgia that is incompletely understood.

Gender Differences in the Clinical Presentation of Cluster Headache: A Role for Sexual Hormones?

Introduction: Cluster Headache (CH) is a well-characterized primary headache that mostly affects men, although a progressive decrease in the male-to-female ratio has occurred over time. Available, but partly discordant, data on gender-related differences in CH suggest a more marked overlapping with migraine features in female subjects. The aim of this study is to carefully evaluate the female/male distribution of the typical migraine-associated symptoms and of other features of the disease in a large and well-characterized clinical population of CH subjects. Materials and Methods: We enrolled consecutive CH patients regularly followed at the tertiary Headache Science Center of the IRCCS Mondino Foundation of Pavia (Italy) who attended the Center for a CH bout between September 2016 and October 2018. The subjects were requested to fill in a semi-structured questionnaire focused on the presence of migraine-associated symptoms, familiarity for migraine and, for women, the relationship of CH onset with the reproductive events of their life. These data were compared and integrated with those recorded over time in our clinical database, including demographics and clinical characteristics. The primary outcome was the gender distribution of subjects who satisfied ICHD-III criterion D for migraine-associated symptoms. The secondary outcomes were represented by the gender distribution of individual migraine-associated symptoms and of other disease features included in the questionnaire and/or in the clinical database. Results: Data from 163 males (mean age 41.46 ± 10.37) and 87 females suffering of CH (mean age 42.24 ± 11.95) were analyzed. We did not find a different distribution between sexes as regards the primary outcome measure (F 73.6%, M 65.6%, p = 0.200). However, when we analyzed the occurrence of individual symptoms, nausea and osmophobia were reported more frequently by women (p = 0.048, p = 0.037, respectively). Ptosis and nasal congestion were predominant in females (p = 0.017 and p = 0.01, respectively), while enlarged temporal artery was more frequently reported by men (p = 0.001). Distribution of pain across the head tended to be larger in women, extending more frequently to the zygomatic (p = 0.050), parietal (p = 0.049), and frontal (p = 0.037) regions. Women had a longer mean attack duration (p = 0.004) than men. In CH women the onset of disease often corresponded with moments of important changes in the levels of sexual hormones (menarche, post-partum, menopause). Concomitant thyroid diseases and psychiatric disorders were observed more frequently in women than in men, while snoring and smoking habit was reported by a higher percentage of men than women. Conclusion: We confirmed the presence of distinct gender-related differences in CH and added some novel information that lends credibility to the hypothesis of a closer phenotypical similarity between CH and migraine in the female sex. These observations are relevant for advancing our knowledge on CH pathophysiology, as well as for a more refined diagnostic framing and improved management of the disease.

The biological clock in cluster headache: A review and hypothesis

Objective

To review and discuss the putative role of light, sleep, and the biological clock in cluster headache.

Discussion

Cluster headache attacks are believed to be modulated in the hypothalamus; moreover, the severe pain and typical autonomic cranial features associated with cluster headache are caused by abnormal activity of the trigeminal-autonomic reflex. The temporal pattern of cluster headache attacks suggests involvement of the biological clock, and the seasonal pattern is influenced by the number of daylight hours. Although sleep is often reported as a trigger for cluster headache attacks, to date no clear correlation has been established between these attacks and sleep stage.

Conclusions

We hypothesize that light, sleep, and the biological clock can change the brain’s state, thereby lowering the threshold for activating the trigeminal-autonomic reflex, resulting in a cluster headache attack. Understanding the mechanisms that contribute to the daily and seasonal fluctuations in cluster headache attacks may provide new therapeutic targets.

Neuroendocrine Associations Underlying the Persistent Therapeutic Effects of Classic Serotonergic Psychedelics

Recent reports on the effects of psychedelic-assisted therapies for mood disorders and addiction, as well as the effects of psychedelics in the treatment of cluster headache, have demonstrated promising therapeutic results. In addition, the beneficial effects appear to persist well after limited exposure to the drugs, making them particularly appealing as treatments for chronic neuropsychiatric and headache disorders. Understanding the basis of the long-lasting effects, however, will be critical for the continued use and development of this drug class. Several mechanisms, including biological and psychological ones, have been suggested to explain the long-lasting effects of psychedelics. Actions on the neuroendocrine system are some such mechanisms that warrant further investigation in the study of persisting psychedelic effects. In this report, we review certain structural and functional neuroendocrinological pathologies associated with neuropsychiatric disorders and cluster headache. We then review the effects that psychedelic drugs have on those systems and provide preliminary support for potential long-term effects. The circadian biology of cluster headache is of particular relevance in this area. We also discuss methodologic considerations for future investigations of neuroendocrine system involvement in the therapeutic benefits of psychedelic drugs.

Cardiovascular Risk Factors in Cluster Headache

Background

Patients with cluster headache tend to have a dysregulation of systemic blood pressure such as increased blood pressure variability and decreased nocturnal dipping. This pattern of nocturnal nondipping is associated with end-organ damage and increased risk of cardiovascular disease.

Objective

To determine if cluster headache is associated with a higher risk of cardiovascular disease.

Methods

Cross-sectional study of 33 cluster headache patients without evidence of cardiovascular disease and 30 age- and gender-matched healthy controls. Ambulatory blood pressure monitoring was performed in all subjects. We evaluate anthropometric, hematologic, and structural parameters (carotid intima-media thickness and ankle-brachial index).

Results

Of the 33 cluster headache patients, 16 (48.5%) were nondippers, a higher percentage than expected. Most of the cluster headache patients (69.7%) also presented a pathological ankle-brachial index. In terms of the carotid intima-media thickness values, 58.3% of the patients were in the 75th percentile, 25% were in the 90th percentile, and 20% were in the 95th percentile. In the control group, only five of the 30 subjects (16.7%) had a nondipper pattern ( P  =   0.004), with 4.54% in the 90th and 95th percentiles ( P  =   0.012 and 0.015).

Conclusions

Compared with healthy controls, patients with cluster headache presented a high incidence (48.5%) of nondipper pattern, pathological ankle-brachial index (69.7%), and intima-media thickness values above the 75th percentile. These findings support the hypothesis that patients with cluster headache present increased risk of cardiovascular disease.

Chronobiology differs between men and women with cluster headache, clinical phenotype does not

Objective:

To describe differences between the sexes in the phenotype of cluster headache (CH) in a large, well-characterized clinical CH population.

Methods:

Patients from the Danish CH survey aged 18–65 years, diagnosed with CH according to International Classification of Headache Disorders, second edition, completed questionnaires and structured interviews.

Results:

A total of 351 patients with CH participated, with a male:female ratio of 2:1. The diurnal variation of attacks showed moments of peak prominence in men’s attack cycle to be advanced by 1 hour compared to women’s, despite no difference in self-reported bedtime or chronotype (p = 0.31). The onset of CH decreased with increasing age for both sexes. Diagnostic delay was numerically longer for men vs women (6.56 vs 5.50 years, p = 0.21); however, more women had previously been misdiagnosed (61.1% vs 45.5%, p < 0.01) and received the correct diagnosis at a tertiary headache center (38.8% vs 20.9%, p < 0.001). Only minor sex differences in clinical characteristics were found but chronic CH was more prevalent in women compared to men (44.0% vs 31.9%, p < 0.05).

Conclusions:

Despite a similar clinical phenotype, diurnal attack cycle is advanced by 1 hour in men with CH compared to women. Rhythmicity is a defining characteristic of CH and these findings suggest differences in the hypothalamus’ influence on attack occurrence between the sexes. In addition, women were more often misdiagnosed and diagnosis in the primary or secondary sector more often failed. Furthermore, women had chronic CH more frequently than men. A long diagnostic delay and frequent misdiagnosis emphasize the need for increased awareness of CH in both sexes.

Hypoxic mechanisms in primary headaches

Background Hypoxia causes secondary headaches such as high-altitude headache (HAH) and headache due to acute mountain sickness. These secondary headaches mimic primary headaches such as migraine, which suggests a common link. We review and discuss the possible role of hypoxia in migraine and cluster headache. Methods This narrative review investigates the current level of knowledge on the relation of hypoxia in migraine and cluster headache based on epidemiological and experimental studies. Findings Epidemiological studies suggest that living in high-altitude areas increases the risk of migraine and especially migraine with aura. Human provocation models show that hypoxia provokes migraine with and without aura, whereas cluster headache has not been reliably induced by hypoxia. Possible pathophysiological mechanisms include hypoxia-induced release of nitric oxide and calcitonin gene-related peptide, cortical spreading depression and leakage of the blood-brain barrier. Conclusion There is a possible link between hypoxia and migraine and maybe cluster headache, but the exact mechanism is currently unknown. Provocation models of hypoxia have yielded interesting results suggesting a novel approach to study in depth the mechanism underlying hypoxia and primary headaches.

Neurobiology and sleep disorders in cluster headache

Cluster headache is characterized by unilateral attacks of severe pain accompanied by cranial autonomic features. Apart from these there are also sleep-related complaints and strong chronobiological features. The interaction between sleep and headache is complex at any level and evidence suggests that it may be of critical importance in our understanding of primary headache disorders. In cluster headache several interactions between sleep and the severe pain attacks have already been proposed. Supported by endocrinological and radiological findings as well as the chronobiological features, predominant theories revolve around central pathology of the hypothalamus. We aimed to investigate the clinical presentation of chronobiological features, the presence of concurrent sleep disorders and the relationship with particular sleep phases or phenomena, the possible role of hypocretin as well as the possible involvement of cardiac autonomic control. We conducted a questionnaire survey on 275 cluster headache patients and 145 controls as well an in-patient sleep study including 40 CH-patients and 25 healthy controls. The findings include: A distinct circannual connection between cluster occurrence and the amount of daylight, substantially poorer sleep quality in patients compared to controls which was present not only inside the clusters but also outside, affected REM-sleep in patients without a particular temporal connection to nocturnal attacks, equal prevalence of sleep apnea in both patient and control groups, reduced levels of hypocretin-1 in the cerebrospinal fluid of patients and finally a blunted response to the change from supine to tilted position in the head-up tilt table test indicating a weakened sympathoexcitatory or stronger parasympathetic drive. Overall, these findings support a theory of involvement of dysregulation in hypothalamic and brainstem nuclei in cluster headache pathology. Further, it is made plausible that the headache attacks are but one aspect of a more complex syndrome of central dysregulation manifesting as sleep-related complaints, sub-clinical autonomic dysregulation and of course the severe attacks of unilateral headache. Future endeavors should focus on pathological changes which persist in the attack-free periods but also heed the possibility of long-lived, cluster-induced pathology.

Headaches and sleep disorders

Headaches and sleep disorders are associated in a complex manner. Both the disorders are common in the general population, but the relationship between the two is more than coincidental. Sleep disorders can exacerbate headache sand the converse is also true. Treatment of sleep disorders can have a positive impact on the treatment of headaches. Screening for sleep disorders should be considered in all patients with headaches. This can be accomplished with brief screening tools. Those who screen positively can be further evaluated or referred to asleep specialist.

Tension-type headache associated with obstructive sleep apnea: a nationwide population-based study

BACKGROUND

There is still controversy regarding the association between primary headaches and obstructive sleep apnea. We explored the relationship between tension-type headache (TTH) and obstructive sleep apnea (OSA) using a large nationwide population-based data set in Taiwan.

METHODS

We identified 4759 patients diagnosed with OSA from the Taiwan Longitudinal Health Insurance Database, based on polysomnography, as the OSA group. We then randomly selected 19036 subjects without OSA, matched by sex and age, to serve as the non-OSA group. The multivariate Cox proportional hazards model with matching for age and sex was used to assess the possible associations between TTH and OSA among the patients.

RESULTS

The prevalence of TTH was 10.2% among OSA patients and 7.7% among non-OSA patients (p < 0.001). The multivariate Cox proportional hazards model revealed patients with OSA were more likely to have TTH (hazard ratio, 1.18; 95% CI, 1.06-1.31) (p = 0.003) than patients in the non-OSA group.

CONCLUSION

Patients with OSA had a higher likelihood of developing TTH than patients in the non-OSA group. Further studies of physiological patterns between OSA and TTH are needed to confirm the study findings.

Sleep and chronobiology in cluster headache

BACKGROUND AND AIM

Cluster headache (CH) is the headache disorder with the strongest chronobiological traits. The severe attacks of pain occur with diurnal and annual rhythmicity but the precise rhythm and involvement of potential zeitgebers is unknown. Patients complain of poor sleep quality yet this has never been studied. We investigated triggers, rhythms, sleep quality and chronotypes in CH.

METHODS

Patients and controls completed questionnaires and structured interviews composed of new and previously validated parts including the Pittsburgh Sleep Quality Index (PSQI) and Morningness-Eveningness Questionnaire (MEQ). Patients were characterized by a CH index, a unified measure of headache burden.

RESULTS

A total of 275 CH patients and 145 matched controls were included. The most common trigger was sleep (80%) and a relationship between clusters and daylight was identified. Of the patients, 82.2% reported diurnal and 56% annual rhythmicity. Patients reported impaired sleep quality (PSQI) (p < 0.0001) and an inverse relationship between time passed since last attack and sleep quality was identified (p < 0.0001). The CH index was positively related to the PSQI (p < 0.0001).

CONCLUSION

Diurnally, CH exhibits a relationship with night-time and annually with daylight hours. Patients' sleep quality is reduced compared with controls. Results suggest a complex relationship as sleep quality improves between clusters, but remains pathological.

Sleep in cluster headache - beyond a temporal rapid eye movement relationship?

BACKGROUND AND PURPOSE

Cluster headache (CH) is a primary headache disorder characterized by severe attacks of unilateral pain following a chronobiological pattern. There is a close connection with sleep as most attacks occur during sleep. Hypothalamic involvement and a particular association with rapid eye movement (REM) sleep have been suggested. Sleep in a large, well-characterized population of CH patients was investigated.

METHODS

Polysomnography (PSG) was performed on two nights in 40 CH patients during active bout and one night in 25 age, sex and body mass index matched controls in hospital. Macrostructure and other features of sleep were analyzed and related to phenotype. Clinical headache characterization was obtained by semi-structured interview.

RESULTS

Ninety-nine nights of PSG were analyzed. Findings included a reduced percentage of REM sleep (17.3% vs. 23.0%, P = 0.0037), longer REM latency (2.0 vs. 1.2 h, P = 0.0012) and fewer arousals (7.34 vs. 14.1, P = 0.003) in CH patients. There was no difference in prevalence of sleep apnea between patients (38%) and matched controls (32%, P = 0.64) although the apnea index in patients was numerically higher (mean apnea-hypopnea index 10.75 vs. 4.93). No temporal association between nocturnal attacks (n = 45) and particular sleep stages was observed.

CONCLUSIONS

To date, this is the largest study of sleep in CH. It is demonstrated that REM sleep is affected which is in line with our current understanding of CH and hypothalamic involvement in the regulation of this sleep stage. Further, fewer arousals were found in CH patients but no association between apnea events or specific sleep stages. The findings support a central role of the hypothalamus and arousal systems in CH.

Sleep apnea in patients with cluster headache: A case-control study

Objective

Polysomnographic investigations have shown an unspecific association between cluster headache and obstructive sleep apnea syndrome. The aim of this study was to investigate this association in a cluster episode compared with a symptom free interval, and to further characterize this association.

Methods

We investigated 42 patients with episodic ( n = 26) or chronic ( n = 16) cluster headache by means of polygraphic screening for sleep apnea and compared the data to 28 healthy control subjects matched according to age, sex, and BMI. The patients with episodic cluster headache were screened twice, once in a cluster episode and once in a symptom free interval.

Results

Patients with active cluster headache showed a significantly higher respiratory distress index (8.6 ± 16.0) compared with healthy control subjects (3.4 ± 2.1; p = 0.002). More patients fulfilled the criteria for an obstructive sleep apnea syndrome (29%) than control subjects (7%; p = 0.018). Patients only, but not the control subjects, had central apneas. These differences were only significant when measured during an active cluster episode but not during a symptom free interval.

Conclusion

Cluster headache is associated with a sleep apnea syndrome only in the active cluster episode. The increased rate of central apneas might be a result of involvement of the hypothalamus in the pathophysiology of cluster headache. Out of five anecdotal cases treated with nasal continuous positive airway pressure, only one patient showed benefit with respect to cluster headache attack frequency.

Sleep in trigeminal autonomic cephalagias: a review

PURPOSE OF REVIEW

Sleep and cluster headache (CH) are believed to be interconnected but the precise relation to the other trigeminal autonomic cephalalgias (TACs) is uncertain and complex. A better understanding of these relations may eventually lead to a clarification of the underlying mechanisms and eventually to more effective therapeutic regimens. This review aims to evaluate the existing literature on the subject of TACs and sleep. An association between episodic CH and distinct macrostructural sleep phases, especially the relation to rapid eye movement (REM) sleep, has been described in some older studies but could not be confirmed in other, more recent studies. Investigations into the microstructure of sleep in these patients are lacking. Only a few case reports exist on the relation between sleep and other TACs.

SUMMARY

Recent studies do not find an association between CH and REM sleep. One older study suggests chronic paroxysmal hemicranias may be locked to REM sleep but otherwise the relation is unknown. Reports indicate that CH and obstructive sleep apnoea are associated in some individuals but results are diverging. Single cases show improvement of CH upon treatment of sleep apnoea, but the causal relationship remains in question. Other TACs are probably not connected to sleep and strictly nocturnal attacks should prompt investigations for secondary causes. The relation between CH and sleep is, however, fascinating and detailed sleep studies in carefully diagnosed patients are warranted.

The relationship between sleep and headache in children: implications for treatment

BACKGROUND

The existence of a correlation and/or comorbidity between sleep disorders and headache, related to common anatomical structures and neurochemical processes, has important implications for the treatment of both conditions.

METHODS

The high prevalence of certain sleep disorders in children with migraine and the fact that sleep is disrupted in these patients highlight the importance of a specific therapy targeted to improve both conditions.

FINDINGS

The treatment of sleep disorders like insomnia, sleep apnea, sleep bruxism and restless legs syndrome, either with behavioral or pharmacological approach, often leads to an improvement of migraine. Drugs like serotoninergic and dopaminergic compounds are commonly used for sleep disorders and for migraine prophylaxis and treatment: Insomnia, sleep-wake transition disorders and migraine have been related to the serotonergic system abnormality; on the other hand prodromal symptoms of migraine (yawning, drowsiness, irritability, mood changes, hyperactivity) support a direct role for the dopaminergic system that is also involved in sleep-related movement disorders.

CONCLUSIONS

Our review of the literature revealed that, beside pharmacological treatment, child education and lifestyle modification including sleep hygiene could play a significant role in overall success of the treatment. Therefore comorbid sleep conditions should be always screened in children with migraine in order to improve patient management and to choose the most appropriate treatment.

Obstructive sleep apnea and other sleep-related syndromes

Obstructive sleep apnea syndrome (OSAS) is a common disorder characterized by repetitive episodes of breathing cessation due to complete or partial collapse of the upper airway therefore affecting ventilation. It is quite common, with a prevalence of about 2-4%, has a strong genetic component, and creates a proinflammatory state with elevated TNFα and other cytokines. If untreated, OSA can lead to significant neurological problems that include stroke, cognitive decline, depression, headaches, peripheral neuropathy, and nonarteritic ischemic optic neuropathy (NAION). Treatment reverses some of these neurological problems. Treatment includes continuous positive airway pressure and its variants, oral appliances, weight loss, upper airway surgery, and rarely maxillofacial procedures. Other sleep breathing disorders such as hypoventilation, central sleep apnea, complex sleep apnea, and Cheyne-Stokes respiration are less common and are sometimes associated with neuromuscular disorders causing diaphragmatic paralysis, but can also be seen in opiate exposure and severe obesity.

Insomnia and periodicity of headache in an arctic cluster headache population

OBJECTIVE

To assess the prevalence of chronic insomnia and the periodicity of headache attacks in an Arctic cluster headache population.

BACKGROUND

Cluster headache is a sleep-related disorder, and attacks have both circadian and circannual rhythmicity.

METHODS

Through a retrospective hospital chart review, we identified all subjects diagnosed with episodic cluster headache (ICD-10 G 44.0) at the Neurological Departments in Northern Norway (located north of 66°33'N) between January 1, 2000 and December 31, 2010. Patients with a confirmed diagnosis (ICHD-2) received a comprehensive questionnaire covering demographic data, clinical characteristics, sleep, and periodicity of attacks.

RESULTS

A total of 196 subjects were registered, and 178 received the questionnaire. The response rate was 88/178 (49%). Fifty-eight men (aged 49.2 ± 13.6) and 12 women (aged 49.7 ± 15.5) were included. Forty percent of the responders suffered from chronic insomnia (Diagnostic and Statistical Manual of Mental Disorders 4th edition). Forty-nine percent of the responders and 42% of the non-responders were shift workers, which is much higher than compared with the general population (24%). Insomnia was significantly associated with shift work and experiencing longer-lasting cluster bouts. One third attributed their insomnia to the cluster headache. Thirty-seven percent reported a seasonal predilection of the cluster periods, and 58% a diurnal periodicity of attacks. Eighty percent often or always had headache attacks during sleep, the most frequent time interval being at 12:00-4:00 am. Shift workers were significantly more likely to see lack of sleep as a cluster attack trigger than daytime workers.

CONCLUSIONS

Chronic insomnia and shift work seem to be common among Arctic cluster headache patients. The small number of subjects included in this study implies that conclusions should be drawn with caution, but the findings support the idea of cluster headache as a circadian rhythm disorder.

Cluster headache and sleep, is there a connection? A review

PURPOSE OF REVIEW

Sleep and the chronobiological disease cluster headache are believed to be interconnected. Despite efforts, the precise nature of the relationship remains obscured. A better understanding of this relation may lead to more effective therapeutic regimes for patients suffering from this debilitating disease. This review aims to evaluate the existing literature on the subject of cluster headache and sleep.

LATEST FINDINGS

Several previous studies describe an association between episodic cluster headache and distinct macrostructural sleep phases. This association was not confirmed in a recent study of seven episodic cluster headache patients, but it was suggested that further studies into the correlation between cluster headache attacks and the microstructure of sleep are relevant. The connection between cluster headache and the hypocretins is currently under investigation.

SUMMARY

There is evidence in favour of an association between episodic cluster headache and REM sleep whereas no such relation to chronic cluster headache has been reported. Particular features in the microstructure of sleep and arousal mechanisms could play a role in the pathogenesis of cluster headache. Reports indicate that cluster headache and obstructive sleep apnoea are associated. Single cases show improvement upon treatment of sleep apnoea, but the causal relationship remains in question.

Cluster headache shows no association with rapid eye movement sleep

BACKGROUND

The connection of cluster headache (CH) attacks with rapid eye movement (REM) sleep has been suggested by various studies, while other authors challenge this assumption. We performed serial polysomnography to determine the association of nocturnal CH attacks and sleep.

METHODS

Five patients diagnosed with CH (two with the episodic and three with the chronic subtype) were included and studied over four consecutive nights to evaluate connections between attacks onset and sleep stage.

RESULTS

Twenty typical CH attacks were reported. Thirteen of these attacks arose from sleep. Seven attacks were reported after waking in the morning or shortly before going to sleep. The beginnings of sleep-related attacks were distributed arbitrarily between different non-REM sleep stages. No association of CH attacks with REM or sleep disordered breathing was observed. Increased heart rate temporally associated with transition from one sleep state to another was observed before patients awoke with headache. Total sleep time, total wake time, arousal index and distribution of non-REM sleep stages were different between chronic and episodic CH.

CONCLUSION

CH attacks are not associated with REM sleep. Brain regions involved in sleep stage transition might be involved in pathophysiology of CH. Differences in sleep characteristics between subgroups might indicate adaptation processes or underlying pathophysiology.

Nighttime blood pressure in cluster headache

BACKGROUND

It has been proposed that desaturation of oxygen during an apnea event is the trigger for cluster headache. Obstructive sleep apnea has been associated with a higher than normal cardiovascular morbidity and mortality. Some obstructive sleep apnea syndrome patients lack the sleep-related, nocturnal decrease, or "dip" in blood pressure, which is seen in normal individuals.

OBJECTIVE

The aim of this study is to assess whether this non-dipper pattern is present in cluster headache patients.

DESIGN AND METHODS

A total of 30 normotensive cluster headache patients underwent an ambulatory blood pressure monitoring. "Non dippers" were defined as patients with a nighttime mean blood pressure fall <10%.

RESULTS

Fifteen cluster headache patients (50%) were non-dippers, a frequency higher than expected. The pattern of nocturnal non-dipping is associated with a higher body mass index. Non-dipper patients displayed higher mean nighttime systolic and diastolic blood pressure. No significant difference was observed in the mean 24-hour and daytime blood pressure.

CONCLUSIONS

The high incidence (50%) of non-dipper pattern in both processes, cluster headache and obstructive sleep apnea syndrome, provides support for the hypothesis of a relationship between theses 2 disorders.

Cluster headache and Alpha 1-antitrypsin deficiency

Little is known about the pathophysiology of cluster headache (CH), one of the most debilitating primary headaches. Interestingly, associations of lung affecting diseases or lifestyle habits such as smoking and sleep apnoea syndrome and CH have been described. Certain genotypes for alpha 1-antitrypsin (alpha(1)-AT) are considered risk factors for emphysema. Our aim was to investigate possible associations between common genotypes of the SERPINA1 gene and CH. Our study included 55 CH patients and 55 controls. alpha(1)-AT levels in serum and the genotype were analysed. Patients CH characteristics were documented. We could not detect any association between CH and a genotype that does not match the homozygous wild type for alpha(1)-AT. Interestingly, there is a significant difference of CH attack frequency in patients who are heterozygous or homozygous M allele carriers. We conclude that the presence of an S or Z allele is associated with higher attack frequency in CH.

Body mass index and headaches: findings from a national sample of US adults

The objective was to study the cross-sectional association between body mass index (BMI) and the prevalence of severe headaches or migraines in a national sample of US adults. We used data from 7601 men and women aged > or = 20 years who participated in the National Health and Nutrition Examination Survey 1999-2002. The age-adjusted prevalence of severe headaches or migraines during the previous 3 months was 34.0, 18.9, 20.7 and 25.9% among participants with a BMI < 18.5, 18.5 to < 25, 25 to < 30 and > or = 30 kg/m(2), respectively. After adjusting for a variety of covariates in a logistic regression model, those with a BMI < 18.5 kg/m(2)[odds ratio (OR) 2.01; 95% confidence interval (CI) 1.34, 3.02] or > or = 30 kg/m(2 )(OR 1.37; 95% CI 1.09, 1.72) had a significantly elevated OR for having a headache compared with participants with a BMI of 18.5-< 25 kg/m(2). BMI is associated with the prevalence of severe headaches or migraines in a non-linear manner.

Refractory Chronic Headache Associated with Obstructive Sleep Apnoea Syndrome

The aim was to investigate the comorbidity of chronic refractory headache with obstructive sleep apnoea syndrome (OSAs). Seventy-two patients (51 women and 21 men) with chronic and refractory headaches, whose headache occurred during sleep or whose sleep was accompanied by snoring, were submitted to polysomnography. Patients diagnosed with OSAs (respiratory disturbance index > 10) began continuous positive airway pressure (C-PAP) treatment and were followed up for ≥ 6 months. Twenty-one cases of OSAs were identified (29.2% of the total investigated, 13.7% of the women and 66.6% of the men). Headaches were classified into several headache disorders, medication overuse headache and cluster headache being the most prevalent (nine and six of the 21 cases, respectively). In one case (1.4% of the total sample, 4.7% of all the men), the criteria for hypnic headache were fulfilled. Multivariate regression analysis revealed that age, male gender and body mass index were associated with OSAs. C-PAP treatment improved both sleep apnoea and headache in only a third of the cases. Patients suffering from chronic refractory headache associated with sleep or snoring, in particular those who are also middle-aged, overweight men, should be considered for polysomnography. C-PAP treatment alone does not seem to improve headache, but further investigation is needed.

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.

Headache and sleep disorders: review and clinical implications for headache management

Review of epidemiological and clinical studies suggests that sleep disorders are disproportionately observed in specific headache diagnoses (eg, migraine, tension-type, cluster) and other nonspecific headache patterns (ie, chronic daily headache, "awakening" or morning headache). Interestingly, the sleep disorders associated with headache are of varied types, including obstructive sleep apnea (OSA), periodic limb movement disorder, circadian rhythm disorder, insomnia, and hypersomnia. Headache, particularly morning headache and chronic headache, may be consequent to, or aggravated by, a sleep disorder, and management of the sleep disorder may improve or resolve the headache. Sleep-disordered breathing is the best example of this relationship. Insomnia is the sleep disorder most often cited by clinical headache populations. Depression and anxiety are comorbid with both headache and sleep disorders (especially insomnia) and consideration of the full headache-sleep-affective symptom constellation may yield opportunities to maximize treatment. This paper reviews the comorbidity of headache and sleep disorders (including coexisting psychiatric symptoms where available). Clinical implications for headache evaluation are presented. Sleep screening strategies conducive to headache practice are described. Consideration of the spectrum of sleep-disordered breathing is encouraged in the headache population, including awareness of potential upper airway resistance syndrome in headache patients lacking traditional risk factors for OSA. Pharmacologic and behavioral sleep regulation strategies are offered that are also compatible with treatment of primary headache.

Headache and sleep

Headache and sleep have long been recognised as being interdependent due to specific causative factors. Yet, the precise understanding of the roles played by these factors in this interdependency remains elusive. Many observations have suggested a reciprocal relationship between headache and sleep; however, these hypotheses have only been partially substantiated by robust findings. Being so, additional well-designed clinical and laboratory studies are required to confirm these relationships. Nonetheless, sleep and headache are known to be related in several ways: primary headache such as migraine, cluster headache (CH) and hypnic headache (HH) can be triggered by sleep, while chronic morning headaches can be caused by sleep disorders such as sleep apnoea and insomnia. Furthermore, headache and sleep disorders can also be symptoms of other underlying pathologies. Migraine, CH and HH seems to be related to sleep stages suggesting that they may in fact be a chronobiological disorder. Patients suffering from chronic morning or nocturnal headache should be considered for the presence of possible sleep disturbances.

Paroxysmal neuralgic upper cervical pain attacks: the lower syndrome of cluster headache

We present a group of seven patients with a lower syndrome (LS) of cluster headache (CH). Seventy-three newly diagnosed patients with CH were subjected to a 9 years follow-up study; 66 patients were classified as upper syndrome (US) and only seven patients (9.5%) as LS. We focus on the characteristics of this group of seven patients with LS and compare them with existing literature. The seven cases with LS illustrate the wider spectrum of clinical manifestations that can occur in CH, namely infraortibal symptoms or these outside the territory of the trigeminal branches such as the upper cervical region or the craniocervical margin. The duration of the attacks can last more than 180 min. The attacks show a circadian/circannual regularity and a stereotypic pattern of symptoms in most of the patients. The severity and duration of the attacks may increase over the years. The neck pain can overshadow all the other symptoms of CH. Because of the regularity of the attacks at particular times of day or night in some patients, even abortive therapy can be used as prevention when taken some hours before the suspected attack. We hypothesize that some patients with LS may represent an anatomical-functional variant of a primary chronic neurovascular pain disorder originating from the central nervous system, with possible involvement of the hypothalamus and the trigeminovascular (TV) system, with inputs from the cervical roots C(0)-C(2). Clinicians should consider CH when pain attacks are located outside the orbitotemporal regions, but fulfil the other diagnostic criteria for CH and should try ergotamine, oxygen, sumatriptan, verapamil, steroids or even combinations in these patients.

Investigation into sleep disturbance of patients suffering from cluster headache

The new discoveries relating to cluster headache (CH) encouraged the study of the relationship of the hypothalamus to respiratory physiology and its comorbidity with sleep apnoea. The question is whether the apnoeas are more frequent during REM sleep and the desaturations could be involved as triggers of the cluster attacks. Furthermore, could the connection with the hypothalamus, already proved, be responsible for an alteration in the structure of REM sleep and a chemoreceptor dysfunction. We set out to analyse when polysomnography investigation is necessary in patients with CH. We studied 37 patients suffering from episodic CH, 31 (83.8%) men and six (16.2%) women. For the control group, we selected 35 individuals, 31 (88.6%) men and four (11.4%) women. There was a greater percentage of obstructive sleep apnoea (OSA) in patients with CH (58.3%) compared with the control group (14.3%) and with the general population (2-4%). In cases of pain during sleep, the majority is deflagrated during the REM phase, following a desaturation episode. A stratified analysis of the apnoea/hypnoea index relating to body mass index (BMI) and age showed that patients with CH have 8.4 times more chance of exhibiting OSA than normal individuals (P < 0001). This risk increases to 24.38 in patients with a BMI > 25 kg/m(2) and increases to 13.5 in patients > 40 years old. Surprisingly, the risk decreases sharply in patients with a BMI < 25 kg/m(2) and who are < 40 years old. Due to the fact that polysomnography is a complex, costly and sometimes difficult examination, we suggest, in concordance with the results, that it should be carried out routinely in patients with CH that exhibit a BMI of > 25 kg/m(2) and/or in patients who are > 40 years of age.

[Sleeping behaviour and headache attacks in cases of primary headache. Possible pathological mechanisms]

Headache is connected with sleep quality, e.g. hypnic headache and chronic paroxysmal headache attacks occur preferentially during REM sleep; this is possibly also true for cluster headache and migraine. REM sleep is typically characterized by the occurrence of ponto-geniculo-occipital spikes (PGOs). These PGOs should be able to trigger cortical spreading depression (CSD), which, although often clinically silent, is assumed to be an essential element of a migraine attack and possibly also of other forms of headache. CSDs are considered a correlate of migraine aura. They could lead to the secondary activation of trigeminovascular afferences, which would then induce a headache. Interestingly, illnesses that are comorbid with migraine cause an increase in the amount of REM sleep; conversely, various drugs administered prophylactically for these illnesses reduce the quantity of REM sleep.

Obstructive sleep apnea and cluster headache

A patient with cluster headache often wakes from sleep. The relationship to sleep apnea has been described. This study sought to confirm the relationship cluster may have with sleep apnea.

METHODS

Thirty-nine consecutive patients diagnosed with episodic cluster headache according to the International Headache Society (IHS) criteria were sent for polysomnographic studies. All patients were in an active phase when they were in the study. Patients were told of the proposed relationship and were allowed to choose a sleep laboratory close to their home.

RESULTS

Thirty-one patients with episodic cluster headache completed an overnight polysomnographic study. Twenty-three were male and eight female. The average age was 51 years (range 33 to 78 years). The average weight was 173 pounds (range 117 to 260 pounds). A total of 80.64% had sleep apnea (25/31). Average respiratory depression index (RDI) was 19.0 (SD 14.6) with 6 patients having no apnea, 10 having mild, 11 having moderate, and 4 having severe apnea (RDI < 5 = none; RDI 5 to 20 mild; RDI 20 to 40 moderate; RDI > 40 severe). Oxygen saturation decreased on average to 88.4% SD 4.5. Sleep efficiency was 76.2% (SD 13.4).

CONCLUSIONS

The data closely approximate those of Chervin et al, where 80% had RDI > 5. The relationship sleep apnea has in the perpetuation or precipitation of cluster headache is still to be determined. There are some reports that treatment stops the cluster but there is no prospective study. The high incidence (80.64%) seen in this population suggests the cluster patient should receive a sleep evaluation and perhaps intervention with continuous positive airway pressure (CPAP) or an appropriate dental device.

Recognition and treatment of cluster headache in the emergency department

Cluster headache has a dramatic presentation marked by rapidly escalating intensity of pain and prominent signs of autonomic dysfunction. Despite its distinctive features, diagnostic delay and misdiagnosis are common. Prompt recognition of this headache disorder provides an opportunity for effective treatment. This article provides a practical approach to the diagnosis and management of patients with cluster headache in the emergency room setting.

Neurologic disorders masquerading as pediatric sleep problems

Neurologic disorders may present or masquerade as pediatric sleep problems and fool the pediatrician, which may delay diagnosis and treatment. Many of the sleep problems in children with neurologic disorders arise directly from primary dysfunction or delayed maturation of their sleep-wake regulation systems. It is important to realize that nocturnal frontal lobe seizures or cluster headaches can be mistaken for night terrors, and craniopharyngiomas or myotonic dystrophy may present as narcolepsy-cataplexy. Hypothalamic dysfunction may explain not only the impaired circadian rhythm disorders in children with profound mental retardation but also excessive sleepiness and hyperphagia in Prader-Willi and Kleine-Levin syndromes. Intellectually challenged children perform better, learn more, and are better behaved with sufficient restorative sleep.

Sleep-related headache syndromes

The relationship between sleep and sleep disorders and headache remains unclear. Clinical experience and numerous studies document some sort of relationship, but the exact nature remains understudied and complex. Changes in sleep duration and sleep quality appear to be capable of affecting headaches of different types. Obstructive sleep apnea can cause or exacerbate headaches in a susceptible person. Obstructive sleep apnea also may cause a specific headache when awakening, which is different from migraine or tension headache and disappears after treatment of the sleep and breathing disturbance. Hypnic headache is another type of sleep-exclusive headache that has been proposed. Hypnic headaches are brief, moderately severe, and affect the elderly primarily.

Cluster headache associated with sleep apnoea

This study of sleep changes in patients with cluster headache (CH) was conducted in view of the nocturnal predominance of this condition, the efficacy of oxygen and the fact that the attacks follow oxygen desaturation. Proposed mechanisms include impairment of carotid body activity secondary to hypothalamic vasomotor regulatory dysfunction. Sixteen patients with episodic CH and 29 healthy volunteers underwent nocturnal polysomnography. Five (31.3%) patients with episodic CH were found to have sleep apnoea (SA). Two patients with SA experienced two attacks during the study period. The attacks followed episodes of oxygen desaturation and were associated with REM sleep. In two patients with SA and CH, treatment with continuous positive airway pressure abolished their oxygen desaturation, sleep apnoeas and headaches. Our study confirmed the high percentage of CH associated with SA. We suggest that oxygen desaturation may be a trigger factor in some patients and play a role in the pathogenesis of CH.