Sleep and migraine: an actigraphic study

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.

Photophobia is associated with lower sleep quality in individuals with migraine: results from the American Registry for Migraine Research (ARMR)

BACKGROUND

Patients with migraine often have poor sleep quality between and during migraine attacks. Furthermore, extensive research has identified photophobia as the most common and most bothersome symptom in individuals with migraine, second only to headache. Seeking the comfort of darkness is a common strategy for managing pain during an attack and preventing its recurrence between episodes. Given the well-established effects of daily light exposure on circadian activity rhythms and sleep quality, this study aimed to investigate the relationship between photophobia symptoms and sleep quality in a cohort of patients with migraine.

METHODS

A cross-sectional observational study was conducted using existing data extracted from the American Registry for Migraine Research (ARMR). Participants with a migraine diagnosis who had completed the baseline questionnaires (Photosensitivity Assessment Questionnaire (PAQ), Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-2 (PHQ-2)), and selected questions of the ARMR Sleep questionnaire were included. Models were created to describe the relationship of photophobia and photophilia with various sleep facets, including sleep quality (SQ), sleep disturbance (SDis), sleep onset latency (SOL), sleep-related impairments (SRI), and insomnia. Each model was controlled for age, sex, headache frequency, anxiety, and depression.

RESULTS

A total of 852 patients meeting the inclusion criteria were included in the analysis (mean age (SD) = 49.8 (13.9), 86.6% (n = 738) female). Those with photophobia exhibited significantly poorer sleep quality compared to patients without photophobia (p < 0.001). Photophobia scores were associated with SQ (p < 0.001), SDis (p < 0.001), SOL (p = 0.011), SRI (p = 0.020), and insomnia (p = 0.005) after controlling for age, sex, headache frequency, depression, and anxiety, signifying that higher levels of photophobia were associated with worse sleep-related outcomes. Conversely, photophilia scores were associated with better sleep-related outcomes for SQ (p < 0.007), SOL (p = 0.010), and insomnia (p = 0.014).

CONCLUSION

Results suggest that photophobia is a significant predictor of poor sleep quality and sleep disturbances in migraine. These results underscore the necessity for comprehensive and systematic investigations into the intricate interplay between photophobia and sleep to enhance our understanding and develop tailored solutions for individuals with migraine.

Sleep Spindle Alterations in Children With Migraine

BACKGROUND

The modulation of thalamocortical activity is the most important site of several levels of interference between sleep spindles and migraine. Thalamocortical circuits are responsible for the electrophysiological phenomenon of sleep spindles. Spindle alterations may be used as a beneficial marker in the diagnosis and follow-up of children with migraine. We aimed to formulate the hypothesis that there is a shared mechanism that underlies migraine and sleep spindle activity.

METHODS

We analyzed the amplitude, frequency, duration, density, and activity of sleep spindles in non-rapid eye movement stage 2 sleep in patients with migraine without aura when compared with healthy control subjects.

RESULTS

The amplitudes of average, slow, and fast sleep spindles were higher in children with migraine without aura (P = 0.020, 0.013, and 0.033, respectively). The frequency of fast spindles was lower in children with migraines without aura when compared with the control group (P = 0.03). Although not statistically significant, the fast sleep spindle duration in the migraine group was shorter (P = 0.055). Multivariate analysis revealed an increased risk of migraine associated with increased mean spindle amplitude and decreased fast spindle frequency and duration.

CONCLUSIONS

Our data suggest that spindle alterations may correlate with the vulnerability to develop migraine and may be used as a model for future research about the association between the thalamocortical networks and migraine.

Circadian Features of Cluster Headache and Migraine: A Systematic Review, Meta-analysis, and Genetic Analysis

BACKGROUND AND OBJECTIVES

Cluster headache and migraine have circadian features at multiple levels (cellular, systems, and behavioral). A thorough understanding of their circadian features informs their pathophysiologies.

METHODS

A librarian created search criteria in MEDLINE Ovid, Embase, PsycINFO, Web of Science, and Cochrane Library. Two physicians independently performed the remainder of the systematic review/meta-analysis using Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Separate from the systematic review/meta-analysis, we performed a genetic analysis for genes with a circadian pattern of expression (clock-controlled genes or CCGs) by cross-referencing genome-wide association studies (GWASs) of headache, a nonhuman primate study of CCGs in a variety of tissues, and recent reviews of brain areas relevant in headache disorders. Altogether, this allowed us to catalog circadian features at the behavioral level (circadian timing, time of day, time of year, and chronotype), systems level (relevant brain areas where CCGs are active, melatonin and corticosteroid levels), and cellular level (core circadian genes and CCGs).

RESULTS

For the systematic review and meta-analysis, 1,513 studies were found, and 72 met the inclusion criteria; for the genetic analysis, we found 16 GWASs, 1 nonhuman primate study, and 16 imaging reviews. For cluster headache behavior, meta-analyses showed a circadian pattern of attacks in 70.5% (3,490/4,953) of participants across 16 studies, with a clear circadian peak between 21:00 and 03:00 and circannual peaks in spring and autumn. Chronotype was highly variable across studies. At the systems level, lower melatonin and higher cortisol levels were reported in cluster headache participants. At the cellular level, cluster headache was associated with core circadian genes CLOCK and REV-ERBα, and 5 of the 9 cluster headache susceptibility genes were CCGs. For migraine behavior, meta-analyses showed a circadian pattern of attacks in 50.1% (2,698/5,385) of participants across 8 studies, with a clear circadian trough between 23:00 and 07:00 and a broad circannual peak between April and October. Chronotype was highly variable across studies. At the systems level, urinary melatonin levels were lower in participants with migraine and even lower during an attack. At the cellular level, migraine was associated with core circadian genes CK1δ and RORα, and 110 of the 168 migraine susceptibility genes were CCGs.

DISCUSSION

Cluster headache and migraine are highly circadian at multiple levels, reinforcing the importance of the hypothalamus. This review provides a pathophysiologic foundation for circadian-targeted research into these disorders.

TRIAL REGISTRATION INFORMATION

The study was registered with PROSPERO (registration number CRD42021234238).

The complexities of the sleep-pain relationship in adolescents: A critical review

Chronic pain is a common and disabling condition in adolescents. Disturbed sleep is associated with many detrimental effects in adolescents with acute and chronic pain. While sleep and pain are known to share a reciprocal relationship, the sleep-pain relationship in adolescence warrants further contextualization within normally occurring maturation of several biopsychological processes. Since sleep and pain disorders begin to emerge in early adolescence and are often comorbid, there is a need for a comprehensive picture of their interrelation especially related to temporal relationships and mechanistic drivers. While existing reviews provide a solid foundation for the interaction between disturbed sleep and pain in youth, we will extend this review by highlighting current methodological challenges for both sleep and pain assessments, exploring the recent evidence for directionality in the sleep-pain relationship, reviewing potential mechanisms and factors underlying the relationship, and providing direction for future investigations. We will also highlight the potential role of digital technologies in advancing the understanding of the sleep and pain relationship. Ultimately, we anticipate this information will facilitate further research and inform the management of pain and poor sleep, which will ultimately improve the quality of life in adolescents and reduce the risk of pain persisting into adulthood.

Erenumab Impact on Sleep Assessed With Questionnaires and Home-Polysomnography in Patients With Migraine: The ERESON Study

Introduction

Migraine and sleep share a complex and unclear relationship. Poor sleep may trigger migraine attacks; migraine, in turn, is frequently associated with sleep disorders. Few previous studies used questionnaires to assess sleep changes in patients who were treated with migraine-preventive medications (MPMs). More extensive polysomnography (PSG)-based studies for this purpose were not available.

Objective

To investigate possible sleep changes in patients with migraine treated with erenumab, using validated sleep questionnaires and home-PSG.

Methods

This observational, prospective, open-label pilot study was conducted at the Clinical Neurology Unit Headache Center of Udine University Hospital from 2020 to 2021. Patients were treated with erenumab as monotherapy or add-on treatment for migraine prevention. Sleep changes were evaluated with questionnaires and polysomnographic recordings at baseline, after 3 and 12 months of treatment. Erenumab efficacy and safety in migraine prophylaxis were also investigated.

Results

Twenty-nine patients completed 3 months of follow-up, whereas 15 patients completed 12 months. We found a weak trend of improvement in daytime somnolence after 3 months of treatment, with stronger results after 12 months (median Epworth Sleepiness Scale (ESS) score from 6.0 to 4.0, p = 0.015); a significant improvement in subjective sleep quality (median Pittsburgh Sleep Quality Index (PSQI) total score from 7 to 5; p = 0.001) was also observed. Home-PSG showed a significant increase in objective sleep efficiency (SE), both after 3 (from 88.1 to 91.0, p = 0.006) and 12 months (from 87.1 to 91.0, p = 0.006) of treatment. In addition, our data confirmed erenumab effectiveness and safety in migraine prevention.

Conclusion

Our study demonstrated an improvement in both subjective and objective sleep quality in patients treated with a migraine-preventive therapy. Erenumab, in particular, does not cross the blood-brain barrier (BBB), thus a direct effect on sleep is unlikely. Future studies are needed to better understand the mutual influence between migraine and sleep disorders.

Headache outcomes of a sleep behavioral intervention in breast cancer survivors: Secondary analysis of a randomized clinical trial

BACKGROUND

Breast cancer survivors often have persisting headache. In a secondary analysis of the Brief Behavioral Therapy for Cancer-Related Insomnia (BBT-CI) clinical trial (ClinicalTrials.gov identifier NCT02165839), the authors examined the effects of BBT-CI on headache outcomes in patients with breast cancer.

METHODS

Patients with breast cancer who were receiving chemotherapy were randomly assigned to receive either the BBT-CI intervention or the Healthy EAting Education Learning for healthy sleep (HEAL) control intervention, and both were delivered over 6 weeks by trained staff. Headache outcomes and heart rate variability (HRV) were measured at baseline, 6 weeks, 6 months, and 12 months. Mixed-effects models were used to examine longitudinal headache outcomes in the groups according to the intention to treat. Principal component analysis and agglomerative hierarchical clustering were conducted to reduce 16 variables for data-driven phenotyping.

RESULTS

Patients in the BBT-CI arm (n = 73) exhibited a significant reduction in headache burden over time (P = .02; effect size [Cohen d] = 0.43), whereas the reduction was not significant among those in the HEAL arm (n = 66). The first principal component was positively loaded by headache, sleep, fatigue, and nausea/vomiting and was negatively loaded by cognitive, physical, and emotional functioning. Agglomerative hierarchical clustering revealed 3 natural clusters. Cluster I (n = 58) featured the highest burden of headache, insomnia, and nausea/vomiting; cluster II (n = 50) featured the lowest HRV despite a low burden of headache and insomnia; and cluster III (n = 31) showed an inverse relation between HRV and headache-insomnia, signifying autonomic dysfunction.

CONCLUSIONS

BBT-CI is efficacious in reducing headache burden in breast cancer survivors. Patient phenotyping demonstrates a headache type featuring sleep disturbance, nausea/vomiting, and low physical functioning-revealing similarities to migraine.

LAY SUMMARY

Breast cancer survivors often have persisting headache symptoms. In patients with cancer, treatment of chronic headache disorders using daily medications may be challenging because of drug interactions with chemotherapy and other cancer therapies as well as patients' reluctance to add more drugs to their medicine list. Headache and sleep disorders are closely related to each other. This study demonstrates that a sleep behavioral therapy reduced headache burden in breast cancer survivors. In addition, the majority of headache sufferers had a headache type with similarities to migraine-featuring sleep disturbance, nausea/vomiting, and low physical functioning.

Subjective Sleep Quality and Sleep Architecture in Patients With Migraine: A Meta-analysis

Background and Objectives

Sleep disturbance is often associated with migraine. However, there is a paucity of research investigating objective and subjective measures of sleep in patients with migraine. This meta-analysis aims to determine whether there are differences in subjective sleep quality measured using the Pittsburgh Sleep Quality Index (PSQI) and objective sleep architecture measured using polysomnography (PSG) between adult and pediatric patients and healthy controls.

Methods

This review was preregistered on PROSPERO (CRD42020209325). A systematic search of 5 databases (Embase, MEDLINE, Global Health, APA PsycINFO, and APA PsycArticles, last searched on December 17, 2020) was conducted to find case–control studies that measured PSG or PSQI in patients with migraine. Pregnant participants and those with other headache disorders were excluded. Effect sizes (Hedges g) were entered into a random effects model meta-analysis. Study quality was evaluated with the Newcastle Ottawa Scale and publication bias with the Egger regression test.

Results

Thirty-two studies were eligible, of which 21 measured PSQI or Migraine Disability Assessment Test in adults, 6 measured PSG in adults, and 5 measured PSG in children. The overall mean study quality score was 5/9; this did not moderate any of the results and there was no risk of publication bias. Overall, adults with migraine had higher PSQI scores than healthy controls (g = 0.75, p < 0.001, 95% confidence interval [CI] 0.54–0.96). This effect was larger in those with a chronic rather than episodic condition (g = 1.03, p < 0.001, 95% CI 0.37–1.01; g = 0.63, p < 0.001, 95% CI 0.38–0.88, respectively). For polysomnographic studies, adults and children with migraine displayed a lower percentage of rapid eye movement sleep (g = −0.22, p = 0.017, 95% CI −0.41 to −0.04; g = −0.71, p = 0.025, 95% CI −1.34 to −0.10, respectively) than controls. Pediatric patients displayed less total sleep time (g = −1.37, p = 0.039, 95% CI −2.66 to −0.10), more wake (g = 0.52, p < 0.001, 95% CI 0.08–0.79), and shorter sleep onset latency (g = −0.37, p < 0.001, 95% CI −0.54 to −0.21) than controls.

Discussion

People with migraine have significantly poorer subjective sleep quality and altered sleep architecture compared to healthy individuals. Further longitudinal empirical studies are required to enhance our understanding of this relationship.

Nightmares in Migraine: A Focused Review

Nightmares usually occur during the sleep phase of rapid eye movement (REM) and are associated with some physical symptoms, including sweating, shortness of breath, and lower limb movements. Emotions of fear, anger, shame, and sadness may also accompany nightmares. These symptoms can occur during dreaming, upon awakening, or later when the dream experience is recollected. Nightmares may sporadically occur for everyone, but nightmare disorders are associated with features of impaired mental and physical health and require professional medical treatment. The occurrence of nightmares with several disorders has been reported in the literature, but in migraines it has only been investigated in a small number of studies. Considering the existing relationship between sleep disorders and migraine, the occurrence of nightmares in migraine can negatively affect this association and elevate the risk of depression and anxiety. This, in turn, further reduces the quality of life of affected individuals. Hence, expanding the knowledge on the link between nightmares and migraine, promoting an acceptable quantity and quality of sleep through pharmacological and nonpharmacological interventions in the management of nightmares in migraine, and further scientific investigation of the biopsychosocial mechanisms underlying the link, will be highly valuable for optimal care. This focused review, therefore, gives a brief overview of the current understanding of nightmares in migraine to highlight the open questions and value of further research. The ultimate goal is to contribute to timely recognition and sufficient action to offer beneficial outcomes for affected patients.

The chronobiology of migraine: a systematic review

Background

The paroxysmal nature of migraine is a hallmark of the disease. Some patients report increased attack frequency at certain seasons or towards the end of the week, while others experience diurnal variations of migraine attack onset. This systematic review investigates the chronobiology of migraine and its relation to the periodicity of attacks in existing literature to further understand the oscillating nature of migraine.

Main body

PubMed and Embase were systematically searched and screened for eligible articles with outcome measures relating to a circadian, weekly or seasonal distribution of migraine attacks. We found that the majority of studies reported morning hours (6 am–12 pm) as the peak time of onset for migraine attacks. More studies reported Saturday as weekly peak day of attack. There was no clear seasonal variation of migraine due to methodological differences (primarily related to location), however four out of five studies conducted in Norway reported the same yearly peak time indicating a possible seasonal periodicity phenomenon of migraine.

Conclusions

The findings of the current review suggest a possible role of chronobiologic rhythms to the periodicity of migraine attacks. Future studies are, however, still needed to provide more knowledge of the oscillating nature of migraine.

Migraine and Sleep-An Unexplained Association?

Migraine and sleep disorders are common chronic diseases in the general population, with significant negative social and economic impacts. The association between both of these phenomena has been observed by clinicians for years and is confirmed by many epidemiological studies. Despite this, the nature of this relationship is still not fully understood. In recent years, there has been rapid progress in understanding the common anatomical structures of and pathogenetic mechanism between sleep and migraine. Based on a literature review, the authors present the current view on this topic as well as ongoing research in this field, with reference to the key points of the biochemical and neurophysiological processes responsible for both these disorders. In the future, a better understanding of these mechanisms will significantly expand the range of treatment options.

A meta-analysis of accelerometer sleep outcomes in healthy children based on the Sadeh algorithm: the influence of child and device characteristics

STUDY OBJECTIVES

Children often experience sleep problems, with a negative impact on mood, behavior, cognitive function, and other aspects of mental and physical health. Accelerometers are widely used to assess sleep, but general reference values for healthy children do not yet exist. The aim of this meta-analysis was to determine mean values for wake after sleep onset (WASO), sleep efficiency (SE), total sleep time (TST) and sleep onset latency (SOL), and to determine the effect of child and accelerometer-characteristics.

METHODS

A search included studies with healthy children, 0-18 years, reporting WASO, SE, TST, and/or SOL, calculated with the Sadeh algorithm. Meta-analyses with random effects produced pooled estimate means per outcome. Meta-regression analyses determined the effect of age, sex, placement site and accelerometer type.

RESULTS

Eighty-three studies (9,068 participants) were included. Pooled means were 63 min (95% CI 57 to 69) for WASO, 88% (95% CI 87 to 89) for SE, 477 min (95% CI 464 to 491) for TST and 19 min (95% CI 17 to 22) for SOL. Heterogeneity was high (95%-99%). TST decreased with age and there was an age-effect on SOL. SE differed between wrist and ankle (used in age 0-24 months) placement, and between piezoelectric and MEMS-type accelerometers. No differences were found between boys and girls, although this number of studies was small.

CONCLUSIONS

We found differences in almost all investigated outcomes and heterogeneity was high. Therefore, we advise to use a study-specific control sample until more robust reference values are available. Future research should narrow the methodological heterogeneity and produce larger datasets, needed to establish these reference values.

Pathophysiological Bases of Comorbidity in Migraine

Despite that it is commonly accepted that migraine is a disorder of the nervous system with a prominent genetic basis, it is comorbid with a plethora of medical conditions. Several studies have found bidirectional comorbidity between migraine and different disorders including neurological, psychiatric, cardio- and cerebrovascular, gastrointestinal, metaboloendocrine, and immunological conditions. Each of these has its own genetic load and shares some common characteristics with migraine. The bidirectional mechanisms that are likely to underlie this extensive comorbidity between migraine and other diseases are manifold. Comorbid pathologies can induce and promote thalamocortical network dysexcitability, multi-organ transient or persistent pro-inflammatory state, and disproportionate energetic needs in a variable combination, which in turn may be causative mechanisms of the activation of an ample defensive system with includes the trigeminovascular system in conjunction with the neuroendocrine hypothalamic system. This strategy is designed to maintain brain homeostasis by regulating homeostatic needs, such as normal subcortico-cortical excitability, energy balance, osmoregulation, and emotional response. In this light, the treatment of migraine should always involves a multidisciplinary approach, aimed at identifying and, if necessary, eliminating possible risk and comorbidity factors.

Associations between migraine attacks and nightly sleep characteristics among adults with episodic migraine: a prospective cohort study

STUDY OBJECTIVES

Given the unknown immediate impact of migraine on nighttime sleep, we prospectively examined whether migraine headaches were associated with subsequent shorter sleep duration, higher fragmentation, and poorer quality in a cohort of 98 adults with episodic migraine.

METHODS

Participants completed twice-daily electronic diaries and wore actigraphs continuously for 6 weeks. We examined whether days with headaches were associated with changes in that night's sleep characteristics compared with headache-free days, using adjusted multivariable linear mixed models with subject-specific intercepts.

RESULTS

Participants were 35 ± 12 years old, 88% women, with an average of five migraine headaches per month. Over 4,406 days, we observed 1,077 headache days, representing 823 discrete headaches. Average nightly objective sleep duration was 7.3 ± 1.2 hr, efficiency 89.5 ± 3.3%, and wake after sleep onset (WASO) 44.8 ± 17.0 min. Objective sleep duration was 7.3 min (95% CI: 1.5, 13.0) longer on nights following a headache day compared with nights on a headache-free day. Objective sleep efficiency, WASO, and reported sleep quality were not significantly different on headache days compared with headache-free days (sleep efficiency: -0.06 min, 95% CI: -0.3, 0.2; WASO 1.5 min, 95% CI: 0.0, 3.0; sleep quality: 1.0, 95% CI: 0.8, 1.3).

CONCLUSIONS

Sleep periods immediately following migraine headaches are not associated with shorter duration, higher disruption, or poorer sleep quality in patients with episodic migraine. These results suggest that clinical evaluation of sleep disturbance in patients with episodic migraine should be approached independently of their migraine status.

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.

A Review on the Triggers of Pediatric Migraine with the Aim of Improving Headache Education

Although migraines are common in children and adolescents, they have a robustly negative impact on the quality of life of individuals and their families. The current treatment guidelines outline the behavioral and lifestyle interventions to correct common causative factors, such as negative emotional states, lack of exercise and sleep, and obesity; however, the evidence of their effectiveness is insufficient. To create a plan for disseminating optimal pediatric headache education, we reviewed the current evidence for factors correlated with migraine. We assessed three triggers or risk factors for migraines in children and adolescents: stress, sleep poverty, and alimentation (including diet and obesity). While there is a gradual uptick in research supporting the association between migraine, stress, and sleep, the evidence for diet-related migraines is very limited. Unless obvious dietary triggers are defined, clinicians should counsel patients to eat a balanced diet and avoid skipping meals rather than randomly limiting certain foods. We concluded that there is not enough evidence to establish a headache education plan regarding behavioral and lifestyle interventions. Clinicians should advise patients to avoid certain triggers, such as stress and sleep disorders, and make a few conservative dietary changes.

Prevalence of Migraine and its Relationship with Psychological Stress and Sleep Quality in Female University Students in Saudi Arabia

Purpose

This study aimed to determine the prevalence of migraine in young female adults and to identify if a relationship exists between psychological stress or poor sleep quality and migraine.

Materials and Methods

This case control study was carried out at Imam Abdulrahman Bin Faisal University (IAU), Dammam, KSA from March 2019 to March 2020 on 1,990 female students (17- to 26-years-old). The study tools were Migraine Screening Questionnaire (MS-Q), International Headache Society (IHS) Criteria for Migraine, K10 Psychological Distress Instrument (K10) and Pittsburgh Sleep Quality Index (PSQI).

Results

A total of 103 out of 1,990 (5.17%) participants were identified to have migraine. Migraineurs compared to controls had significantly higher average stress scores; felt more tired, nervous, restless, could not sit still, felt that everything was an effort, and nothing cheered them up (p values; 0.008, 0.001, 0.02, 0.01, 0.004, 0.009, 0.02 respectively). Moreover, presence of migraine was significantly correlated with various stress parameters including "High K10 scores," "being tired," "being nervous," "restlessness," "inability to sit still," and "feeling that everything is an effort" (p values: 0.01, 0.002, 0.018, 0.01,0.005, 0.01,0.02). Regarding sleep quality and sleep parameters, no statistically significant difference was found between migraineurs and controls. No correlation was found between presence of migraine and poor sleep quality.

Conclusions

The results of this study indicate that 5.17% of young females (17- to 26-years-old) suffer from migraine. It also concludes that poor sleep quality is not correlated with migraine, whereas high stress scores are significantly correlated with migraine in young female adults.

Nightly sleep duration, fragmentation, and quality and daily risk of migraine

OBJECTIVE

To test the hypotheses that insufficient duration, high fragmentation, and poor sleep quality are temporally associated with migraine onset on the day immediately following the sleep period (day 0) and the following day (day 1).

METHODS

In this prospective cohort study of 98 adults with episodic migraine, participants completed twice-daily electronic diaries on sleep, headaches, and other health habits, and wore wrist actigraphs for 6 weeks. We estimated the incidence of migraine following nights with short sleep duration, high fragmentation, or low quality compared to nights with adequate sleep with conditional logistic regression models stratified by participant and adjusted for caffeine intake, alcohol intake, physical activity, stress, and day of week.

RESULTS

Participants were a mean age of 35.1 ± 12.1 years. We collected 4,406 days of data, with 870 headaches reported. Sleep duration ≤6.5 hours and poor sleep quality were not associated with migraine on day 0 or day 1. Diary-reported low efficiency was associated with 39% higher odds of headache on day 1 (odds ratio [OR] 1.39, 95% confidence interval [CI] 1.06-1.81). Actigraphic-assessed high fragmentation was associated with lower odds of migraine on day 0 (wake after sleep onset >53 minutes, OR 0.64, 95% CI 0.48-0.86; efficiency ≤88%, OR 0.74, 95% CI 0.56-0.99).

CONCLUSION

Short sleep duration and low sleep quality were not temporally associated with migraine. Sleep fragmentation, defined by low sleep efficiency, was associated with higher odds of migraine on day 1. Further research is needed to understand the clinical and neurobiologic implications of sleep fragmentation and risk of migraine.

Actigraphic Sleep Pattern of Preschoolers With ADHD

Objective: To assess the features of sleep in preschoolers with ADHD by means of questionnaire and actigraphy. Method: Twenty-five ADHD and 21 age-matched typically developing (TD) preschool children underwent the Child Behavior Checklist (CBCL) for ages 1½ to 5 and Pre-School-Age Psychiatric Assessment interview. Sleep was assessed by means of a modified Sleep Disturbance Scale for Children and wrist actigraphy for at least 5 days. Results: Children with ADHD, compared with TD, showed higher scores in CBCL Withdrawal (58.83 vs. 51.15, p < .0001), Attention Problems (69.88 vs. 51.54, p < .0001), and Aggressive Behavior (59.46 vs. 51.08, p < .0001) dimensions; they also showed increased actigraphic nocturnal activity (activity index 31.57 vs. 25.74, p < .05); and night-to-night variability for sleep minutes (56.44 vs. 32.79, p < .01), mean wake episodes (1.34 vs. 0.98, p < .05), mean activity (2.64 vs. 1.71, p < .05), and activity index (5.15 vs. 3.77, p < .05). Conclusion: This pilot study in preschoolers with ADHD showed increased motor activity during sleep and night-to-night variability for sleep duration and motor activity.

Nonpharmacological Interventions Addressing Pain, Sleep, and Quality of Life in Children and Adolescents with Primary Headache: A Systematic Review

Purpose

Children and adolescents with primary headache are at risk of persistent somatic symptoms and reduced quality of life (Qol) due to pain and pain-related behaviors, such as avoiding school and activities. Sleep is essential to health, and children and adolescents with primary headaches have more sleep complaints than do healthy controls. A treatment approach that addresses multifactorial causes is likely important. Nonpharmacological interventions seem promising. However, knowledge about effective strategies is limited. The objective of this review is to assess the effect of nonpharmacological interventions in randomized controlled trials (RCTs) among children and adolescents with primary headache in order to identify useful strategies.

Patients and methods

Outcome measures are pain, sleep, Qol, and coping versus no intervention or control intervention. Medline, CINAHL, EMBASE, and PsycINFO were searched for eligible trials. ClinicalTrials.gov. was searched for ongoing trials. Initial searches yielded 2588 publications. After initial screening and subsequent full-text review and quality assessment, 13 RCTs reported in 15 articles were selected for review. All reviewers independently assessed study quality using the CONSORT criteria for nonpharmacological interventions.

Results

Cognitive behavioral therapy (CBT), including education on pain-related topics, sleep, coping, and stress management, is an effective strategy for reducing headache and pain within groups over time. Fifteen studies assessed pain, 3 studies assessed sleep, 6 studies assessed Qol, and 11 studies assessed coping.

Conclusion

Strategies identified as useful were parts of CBT interventions. However, it was not possible to identify a single effective intervention addressing pain, sleep, Qol, and coping in children and adolescents with headache, primarily because sleep was infrequently addressed. Various aspects of Qol and coping strategies were assessed, rendering comparison difficult. Strategies for future interventions should include descriptions of theory-driven CBT interventions, depending on clinical setting and based on local resources, to promote a solid evidence base for nonpharmacological interventions.

NREM Sleep Instability in Pediatric Migraine Without Aura

Children with migraine headaches appear to have a range of sleep disturbances. The aim of the present study was to assess the NREM sleep instability in a population of school-aged individuals affected by migraine without aura (MoA). Thirty-three children with MoA (20 males, 13 females, mean age 10.45 ± 2.06 years) underwent to overnight Polysomnographic (PSG) recordings and Cyclic Alternating Pattern (CAP) analyses accordingly with international criteria. MoA group showed a reduction in sleep duration parameters (TIB, SPT, TST; p ≤ 0.001 for all) and in arousal index during REM sleep and an increase in awakenings per hour (AWK/h) vs. Controls (C) (p = 0.008). In particular, MoA children showed a reduced CAP rate% (p ≤ 0.001), CAP rate% in S1 (p ≤ 0.001) and CAP rate% in SWS (p = 0.004) vs. C. Moreover, A phases distribution were characterized by a reduction in slow wave components (total number CAP A1%, CAP A1 index) (p ≤ 0.001) and an increase of fast components representation (total number of CAP A2% and CAP A3%) (p < 0.001) in MoA vs. C. Moreover, MoA children showed an increased A1 and A2 mean duration (p ≤ 0.001). Our findings show a reduction of arousability in MoA group and lower NREM lower sleep instability associated with MoA in children.

Headaches and sleep problems in US adolescents: Findings from the National Comorbidity Survey - Adolescent Supplement (NCS-A)

BACKGROUND

There is limited research on the association of sleep problems with International Classification of Headache Disorders (ICHD-II)-defined headache subtypes in youth, particularly from community-based samples. This cross-sectional study examines the associations of sleep patterns, symptoms and disorders with specific headache subtypes among adolescents from the general population of the United States.

METHODS

The sample includes 10,123 adolescents in the National Comorbidity Survey - Adolescent Supplement, a face-to-face survey of adolescents aged 13-18 years in the continental USA. Headache subtype diagnoses were based on modified ICHD-III criteria, and mood and anxiety disorders were based on Diagnostic and Statistical Manual of Mental Disorders criteria. The associations of self-reported sleep patterns and insomnia symptoms and headache status were estimated with multivariate regression models that adjust for demographic characteristics and comorbid anxiety and mood disorders.

RESULTS

There was no significant difference in bedtime between youth with and without headache. However, adolescents with migraine headache reported significantly shorter sleep duration (p = .022) and earlier wakeup time (p = .002) than those without headache. Youth with any headache, particularly migraine, had significantly more sleep disturbances than those without headache. With respect to headache subtypes, youth with migraine with aura were more likely to report difficulty maintaining sleep, early morning awakening, daytime fatigue, and persistent insomnia symptoms than those with migraine without aura. However, these associations were largely accounted for by comorbid anxiety and mood disorders. There was a monotonic increase in the number of insomnia symptoms with increasingly restrictive definitions of migraine.

CONCLUSION

Pervasive sleep disturbances in adolescents with headache have important implications for the evaluation, treatment and etiology of pediatric headache.

Sleep in cluster headache revisited: Results from a controlled actigraphic study

Background and aim

Cluster headache attacks exhibit a nocturnal predilection, but little is known of long-term sleep and circadian rhythm. The aim was to compare actigraphy measures, firstly in episodic cluster headache patients in bout and in remission and, secondly, to compare each disease phase with controls.

Methods

Episodic cluster headache patients (ICHD III-beta), from the Danish Headache Center and healthy, age- and sex-matched controls participated. Sleep and activity were measured using actigraphy continuously for 2 weeks, along with sleep diaries and, for patients, also attack registration.

Results

Patients in bout (n = 17, 2.3 attacks/day) spent more time in bed (8.4 vs. 7.7 hours, p = 0.021) and slept more (7.2 vs. 6.6 hours, p = 0.036) than controls (n = 15). In remission (n = 11), there were no differences compared with controls. Neither were there differences between patients in the two disease phases. In five patients, attacks/awakenings occurred at the same hour several nights in a row.

Conclusion

Actigraphy offers the possibility of a continuous and long study period in a natural (non-hospital) environment. The study indicates that sleep does not differ between the bout and remission phase of episodic cluster headache. The repeated attacks/awakenings substantiate that circadian or homeostatic mechanisms are involved in the pathophysiology. The protocol was made available at ClinicalTrials.gov (NCT02853487).

Sleep Disorders and Migraine: Review of Literature and Potential Pathophysiology Mechanisms

Migraine shares a complex and poorly understood relationship with sleep. Patients consistently report poor sleep prior to migraine attacks and during them, identifying poor sleep as a migraine trigger. However, anecdotally, sleep is reported to serve a therapeutic role in terminating headache. Are the associations between migraine and sleep simply the result of various bidirectional relationships? A growing body of evidence suggests there may be a common underlying etiology as well. Our objective was to review studies of sleep and migraine from the last 2 decades utilizing validated subjective and objective measures of sleep and to explore potential mechanisms underlying this complex relationship by incorporating recent advances in neuroscience. We specifically focus on insomnia, obstructive sleep apnea, parasomnias, sleep related movement disorders, and REM sleep related disorders and their relationship to migraine. Parts of brainstem-cortical networks involved in sleep physiology are unintentionally being identified as important factors in the common migraine pathway. Recent discoveries on anatomic localization (the hypothalamus as a key and early mediator in the pathophysiology of migraine), common mediating signaling molecules (such as serotonin and dopamine), and the discovery of a new CNS waste removal system, the glymphatic system, all point to a common pathophysiology manifesting in migraine and sleep problems.

Poor sleep quality in migraine and probable migraine: a population study

Background

Probable migraine (PM) is a subtype of migraine that is prevalent in the general population. Previous studies have shown that poor sleep quality is common among migraineurs and is associated with an exacerbation of migraine symptoms. However, information on the prevalence and clinical implication of poor sleep quality among individuals with PM is scarce. Thus, the aim of this study was to assess the prevalence and clinical impact of poor sleep quality in individuals with PM in comparison with those with migraine.

Methods

Two-stage cluster random sampling was used to perform the survey for sleep and headache in Korean general population. Participants with Pittsburgh Sleep Quality Index > 5 were considered as having poor sleep quality.

Results

Of 2695 participants, 379 (14.1%) had PM and 715 (26.5%) had poor sleep quality. Prevalence of poor sleep quality was 35.4% in the PM group, which was lower than that in the migraine group (47.6%, p = 0.011), but higher than that in the non-headache group (21.4%, p < 0.001). The PM participants with poor sleep quality showed increased headache frequency (median [interquartile range]: 2.0 [0.3–4.0] vs. 1.0 [0.2–2.0]; p = 0.001) and headache intensity (visual analogue scale, 6.0 [4.0–7.0] vs. 5.0 [3.5–6.0]; p = 0.003) compared to PM participants who had no poor sleep quality.

Conclusions

Poor sleep quality was prevalent among participants with PM. It was associated with an exacerbation of PM symptoms. Our findings suggest that proper evaluation and treatment for poor sleep quality are needed in the management of PM.

Electronic supplementary material

The online version of this article (10.1186/s10194-018-0887-6) contains supplementary material, which is available to authorized users.

PACAP in hypothalamic regulation of sleep and circadian rhythm: importance for headache

The interaction between sleep and primary headaches has gained considerable interest due to their strong, bidirectional, clinical relationship. Several primary headaches demonstrate either a circadian/circannual rhythmicity in attack onset or are directly associated with sleep itself. Migraine and cluster headache both show distinct attack patterns and while the underlying mechanisms of this circadian variation in attack onset remain to be fully explored, recent evidence points to clear physiological, anatomical and genetic points of convergence. The hypothalamus has emerged as a key brain area in several headache disorders including migraine and cluster headache. It is involved in homeostatic regulation, including pain processing and sleep regulation, enabling appropriate physiological responses to diverse stimuli. It is also a key integrator of circadian entrainment to light, in part regulated by pituitary adenylate cyclase-activating peptide (PACAP). With its established role in experimental headache research the peptide has been extensively studied in relation to headache in both humans and animals, however, there are only few studies investigating its effect on sleep in humans. Given its prominent role in circadian entrainment, established in preclinical research, and the ability of exogenous PACAP to trigger attacks experimentally, further research is very much warranted. The current review will focus on the role of the hypothalamus in the regulation of sleep-wake and circadian rhythms and provide suggestions for the future direction of such research, with a particular focus on PACAP.

Sleep in Patients with Chronic Migraine

PURPOSE OF REVIEW

The biological and pathophysiological interaction between sleep and chronic migraine (CM) remains to be fully elucidated. In this article, we provide a narrative review of the literature on sleep disturbance and CM, highlighting recent advances in sleep research and insights into mechanisms that could mediate a role of sleep disturbances in migraine chronification. We discuss the potential for cognitive-behavioral insomnia therapy (CBTi) as an intervention for CM with comorbid insomnia. Finally, we propose a model of the mechanisms underlying the interactions among sleep physiology, maladaptive migraine-coping behaviors, and coexisting factors which contribute to sleep disturbances in CM based on conceptual models used in sleep research.

RECENT FINDINGS

Insomnia is the most common sleep complaint among patients with CM. CM patients experience more frequent and severe insomnia symptoms than patients with episodic migraine (EM). It has been suggested that sleep disturbances may predispose individuals to migraine attacks, which may affect the pain-processing trigeminovascular system and thus play a role in migraine progression. Encouraging but limited evidence suggests that management of insomnia via behavioral sleep therapy may reverse CM to EM and possibly prevent migraine chronification. Migraine has a complex relationship with sleep. The use of objective sleep study such as polysomnographic microstructural sleep analysis and actigraphy could help connect sleep disturbances and processes related to CM. Future longitudinal studies should examine whether effective behavioral treatments such as CBTi can reverse migraine chronification.

Sleep Disorders in Childhood Neurological Diseases

Sleep problems are frequently addressed as a primary or secondary concern during the visit to the pediatric neurology clinic. Sleep disorders can mimic other neurologic diseases (e.g., epilepsy and movement disorders), and this adds challenges to the diagnostic process. Sleep disorders can significantly affect the quality of life and functionality of children in general and those with comorbid neurological diseases in particular. Understanding the pathophysiology of sleep disorders, recognizing the implications of sleep disorder in children with neurologic diseases and behavioral difficulties, and early intervention continue to evolve resulting in better neurocognitive outcomes.

Resting-state EEG power and coherence vary between migraine phases

Background

Migraine is characterized by a series of phases (inter-ictal, pre-ictal, ictal, and post-ictal). It is of great interest whether resting-state electroencephalography (EEG) is differentiable between these phases.

Methods

We compared resting-state EEG energy intensity and effective connectivity in different migraine phases using EEG power and coherence analyses in patients with migraine without aura as compared with healthy controls (HCs). EEG power and isolated effective coherence of delta (1–3.5 Hz), theta (4–7.5 Hz), alpha (8–12.5 Hz), and beta (13–30 Hz) bands were calculated in the frontal, central, temporal, parietal, and occipital regions.

Results

Fifty patients with episodic migraine (1–5 headache days/month) and 20 HCs completed the study. Patients were classified into inter-ictal, pre-ictal, ictal, and post-ictal phases (n = 22, 12, 8, 8, respectively), using 36-h criteria. Compared to HCs, inter-ictal and ictal patients, but not pre- or post-ictal patients, had lower EEG power and coherence, except for a higher effective connectivity in fronto-occipital network in inter-ictal patients (p < .05). Compared to data obtained from the inter-ictal group, EEG power and coherence were increased in the pre-ictal group, with the exception of a lower effective connectivity in fronto-occipital network (p < .05). Inter-ictal and ictal patients had decreased EEG power and coherence relative to HCs, which were “normalized” in the pre-ictal or post-ictal groups.

Conclusion

Resting-state EEG power density and effective connectivity differ between migraine phases and provide an insight into the complex neurophysiology of migraine.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-016-0697-7) contains supplementary material, which is available to authorized users.

Lifestyle Factors and Migraine in Childhood

Migraine is one of the most common pain symptoms in children. Indeed, a high percentage of adult migraine patients report to have suffered from recurrent headache during the childhood. In particular, children could experience the so-called childhood periodic syndromes (such as cyclic vomiting, abdominal migraine, and benign paroxysmal vertigo) that have been usually considered precursors of migraine or they could develop overt migraine headaches. However, typical cohort of migraine symptoms could be absent and children could not achieve all clinical features necessary for a migraine attack diagnosis according to classification criteria. Nevertheless, migraine is characterized also in childhood by a significant negative impact on the quality of life and a high risk of developing chronic and persistent headache in adulthood. Several studies have emphasized the role of different risk factors for migraine in children. Among these, obesity and overweight, particular food or the regular consumption of alcohol or caffeine, dysfunctional family situation, low level of physical activity, physical or emotional abuse, bullying by peers, unfair treatment in school, and insufficient leisure time seem to be strictly related to migraine onset or progression. Consequently, both identification and avoidance of triggers seem to be mandatory in children with migraine and could represent an alternative approach to the treatment of migraine abstaining from pharmacologic therapies.

Circadian Rest-Activity Rhythm in Pediatric Type 1 Narcolepsy

STUDY OBJECTIVES

Pediatric type 1 narcolepsy is often challenging to diagnose and remains largely undiagnosed. Excessive daytime sleepiness, disrupted nocturnal sleep, and a peculiar phenotype of cataplexy are the prominent features. The knowledge available about the regulation of circadian rhythms in affected children is scarce. This study compared circadian rest-activity rhythm and actigraphic estimated sleep measures of children with type 1 narcolepsy versus healthy controls.

METHODS

Twenty-two drug-naïve type 1 narcolepsy children and 21 age- and sex- matched controls were monitored for seven days during the school week by actigraphy. Circadian activity rhythms were analyzed through functional linear modeling; nocturnal and diurnal sleep measures were estimated from activity using a validated algorithm.

RESULTS

Children with type 1 narcolepsy presented an altered rest-activity rhythm characterized by enhanced motor activity throughout the night and blunted activity in the first afternoon. No difference was found between children with type 1 narcolepsy and controls in the timing of the circadian phase. Actigraphic sleep measures showed good discriminant capabilities in assessing type 1 narcolepsy nycthemeral disruption.

CONCLUSIONS

Actigraphy reliably renders the nycthemeral disruption typical of narcolepsy type 1 in drug-naïve children with recent disease onset, indicating the sensibility of actigraphic assessment in the diagnostic work-up of childhood narcolepsy type 1.

Sleep disturbances among pregnant women with history of migraines: A cross-sectional study

BACKGROUND

Migraine is associated with sleep disturbances in men and non-pregnant women. However, relatively little is known about sleep disturbances among pregnant migraineurs. We investigated sleep disturbances among pregnant women with and without history of migraine.

METHODS

This cross-sectional study was conducted among 1324 women who were recruited during early pregnancy. Migraine diagnoses were based on the International Classification of Headache Disorders-II criteria. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was used to evaluate sleep-related characteristics including sleep duration, sleep quality, excessive daytime sleepiness, and other sleep traits. Multivariable logistic regression procedures were used to estimate adjusted odds ratios (AORs) and 95% confidence intervals (CIs).

RESULTS

Migraineurs were more likely than non-migraineurs to report short sleep duration (<6.5 hours) (AOR = 1.47, 95% CI 1.07-2.02), poor sleep quality (PSQI>5) (AOR = 1.73, 95% CI 1.35-2.23), and daytime dysfunction due to sleepiness (AOR = 1.51, 95% CI 1.12-2.02). Migraineurs were also more likely than non-migraineurs to report taking sleep medication during pregnancy (AOR = 1.71, 95% CI 1.20-2.42). Associations were generally similar for migraine with or without aura. The odds of sleep disturbances were particularly elevated among pre-pregnancy overweight migraineurs.

CONCLUSION

Migraine headache and sleep disturbances are common comorbid conditions among pregnant women.

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.

Sleep and Headache

The interaction between sleep and headache or migraine is powerful and an elevated comorbidity between these 2 disorders has been reported in either adults or children. This comobidity is linked to common neurophysiological and neuroanatomical substrates that are genetically based strongly. The first reports on this relationship were related to the prevalence of parasomnias and sleep-disordered breathing in headache but recent research has expanded the comorbidity to several other sleep disorders, such as restless legs syndrome, periodic limb movements during sleep, and narcolepsy. The assessment of children with headache should always include an accurate anamnesis for the presence of sleep problems either in the child or in the relatives; no correct approach for treating children and adolescents is possible without an integrated method of evaluation and management.

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.

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.

Pathophysiology of hypnic headache

Background

Hypnic headache (HH) is a rare primary headache disorder that is characterized by strictly sleep related headache attacks.

Purpose

The underlying pathophysiology of HH is mainly enigmatic but some clinical characteristics such as circadian rhythmicity and caffeine responsiveness may point toward possible underlying mechanisms.

Method

Current studies that deal with the pathophysiology of HH are summarized. Data on cerebral imaging, sleep, electrophysiology studies, effectiveness of drugs, and symptomatic headache types are discussed to illuminate underlying pathophysiologic mechanisms.

Conclusion

HH can be clearly differentiated by its clinical presentation as well as imaging and electrophysiological study results from other primary headaches such as migraine or cluster headache. The underlying pathophysiology is still enigmatic but a hypothalamic involvement seems to be likely.

Histamine in migraine and brain

BACKGROUND

Histamine has been studied in both health and disease since the initial description a century ago. With its vasodilative effect, it was suggested early on to be involved in the pathophysiology of migraine. Over the past 25 years, much has been learned about histamine as a neurotransmitter in the central nervous system. The role of this neurotransmitter system in migraine has not been previously reviewed.

OBJECTIVE

Discuss a potential role of the brain histaminergic system in migraine.

METHODS

Unstructured literature search with a no specific hypothesis-driven approach.

RESULTS

There is substantial evidence that systemically given histamine may elicit, maintain, and aggravate headache. The mechanisms for this are not known, and histamines do not penetrate the blood-brain barrier (BBB). However, circulating histamine may influence hypothalamic activity via the circumventricular organs that lack BBB. In the rat, prolonged activation of meningeal nociceptors induced by dural mast cell degranulation has been observed. Subcutaneous injections of N-alpha-methyl histamine, a catabolite of histamine with high affinity to the histamine H3 receptor, probably have some migraine preventive effect. A negative feedback on histamine release from mast cells in proximity to C-fiber endings has been a postulated mechanism. Most antihistamines have shown to be ineffective as acute medication for migraine. Two centrally acting potent H1 receptor antagonists (cinnarizine and cyproheptadine) have been reported to be efficacious in preventing migraine. However, the proof for this is limited, and their efficacy has been ascribed other actions than the antihistaminergic. In general, lack of specificity and side effects limit the potential use of centrally acting H1 and H2 antagonists. Brain histamine is synthesized by neurons that are restricted to the posterior basal hypothalamus, more specific to the tuberomamillary nucleus (TMN), and that project practically to the whole central nervous system. The posterior hypothalamus is a suspected locus in quo in several primary headaches. Recently, a positron emission tomography study performed in the prodromal phase of migraine attacks supported the idea of initial involvement of this area. In another recent study, the thalamic nuclei receiving trigeminal output was also shown to have direct connections with the ventral TMN. The central histaminergic system plays an important role in the complex sleep-wake cycle, promoting cortical excitability during wakening and attention, and it consolidates the wake state. The period of the day, in the evenings and during the night, when there is reduced susceptibility for migraine attacks corresponds with less central histaminergic firing. Activation of both the H3 and the H4 receptor promotes inhibitory actions on neurons. The H3 receptor causes autoinhibition of the histaminergic neurons themselves, and centrally acting H3 receptor agonist prodrugs have shown to both inhibit neurogenic inflammation in dura, to induce sleep, and to produce antinociception. There are no registered ongoing studies on H3 and H4 receptor ligands in migraine.

CONCLUSION

The role of the central histaminergic system in migraine is largely unexplored, but findings from preclinical research may be linked to several aspects of the disorder. The histaminergic system of the brain may play an important role, especially in the initial phase of an attack, and histamine H3 and H4 receptor ligands may potentially have migraine prophylactic properties. However, the basis for this is still circumstantial, and the evidence is lacking.

Hypnic headache

Background

Hypnic headache (HH) is a rare primary headache disorder that is characterised by strictly sleep-related headache attacks.

Purpose

Because of the low prevalence of this headache disorder, disease information is mainly based on case reports and small case series. This review summarises current knowledge on HH in regard to clinical presentation, pathophysiology, symptomatic causes and therapeutic options.

Method

We review all reported HH cases since its first description in 1988 by Raskin. Broadened diagnostic criteria were applied for patient selection that slightly deviate from the current ICHD-II criteria. Patients were allowed to describe the headache character to be other than dull. Additionally, accompanying mild trigemino-autonomic symptoms were permitted.

Conclusions

Mainly elderly patients are affected, but younger patients and even children might also suffer from HH. Headache attacks usually last between 15 and 180 minutes, but some patients report headache attacks up to 10 hours. Almost all patients report motor activity during headache attacks. Cerebral MRI and 24-hour blood pressure monitoring should be performed in the diagnostic work-up of HH. Other primary headache disorders such as migraine and cluster headache may also present with sleep-related headache attacks and should be considered first. Caffeine taken as a cup of strong coffee seems to be the best acute and prophylactic treatment option.

Comorbidities of sleep disorders in childhood and adolescence: focus on migraine

The correlation and/or comorbidity between sleep disorders and headache has been reported in numerous studies, but the exact nature of the association between headache, disordered sleep, and underlying mechanisms remains poorly understood. The bidirectional association between sleep and headache is mediated by a temporal link (headache occurs during sleep, after sleep, and in relationship with sleep stages), by a quantitative relationship (excess, lack, bad quality, short duration of sleep may trigger headache), and by a reciprocal connection (headache may cause sleep disruption and may be associated with several sleep disturbances). This association is most evident for primary headache disorders, especially in childhood. A congenital alteration of neurotransmitter pathways (serotoninergic and dopaminergic) might predispose individuals to both disorders, presenting as sleep-wake rhythm disorder in infancy or as headache disorder later in childhood, as result of this neurotransmitter imbalance. Clinicians should be aware that a complete clinical evaluation of childhood headache includes a careful sleep history, taking into account that the treatment of sleep disturbances could lead to an improvement of headache symptoms and vice versa.

A systematic review of sleep in pediatric pain populations

OBJECTIVE

The primary aim of this systematic review was to examine the evidence for a pain-sleep relationship in children with persistent pain by reviewing studies using single and mixed pediatric persistent pain samples.

METHODS

Electronic searches of Medline, PubMed, the Cochrane Database of Systematic Reviews, and PsycINFO were conducted to identify all relevant empirical studies. Studies were included in the review if the majority of participants were between 0 and 17 years and from one of the following pediatric pain populations: juvenile idiopathic arthritis, sickle cell disease, migraine/headache, functional abdominal pain, juvenile fibromyalgia syndrome, chronic musculoskeletal pain, or mixed populations including the aforementioned conditions.

RESULTS

Research from single and mixed sample studies support the hypothesis that children and adolescents with persistent pain suffer from sleep impairment. Literature addressing factors that may influence or mediate the pain-sleep relationship and the functional outcomes of the pain-sleep relationship was reviewed, and a model of the interrelationships with pain and sleep was developed.

CONCLUSION

Findings from this review highlight the need to assess and treat sleep problems in children presenting with persistent pain. Health care providers should consider conducting routine sleep screenings, including a comprehensive description of sleep patterns and behaviors obtained through clinical interview, sleep diaries, and/or the use of standardized measures of sleep. Future research focusing on investigating the mechanisms associating sleep and pediatric persistent pain and on functional outcomes of poor sleep in pediatric pain populations is needed.

Sleep loss as risk factor for neurologic disorders: a review

Sleep loss refers to sleep of shorter duration than the average baseline need of seven to eight hours per night. Sleep loss and sleep deprivation have severe effects on human health. In this article, we review the main aspects of sleep loss, taking into account its effects on the central nervous system. The neurocognitive and behavioral effects of sleep loss are well known. However, there is an increasing amount of research pointing to sleep deprivation as a risk factor for neurologic diseases, namely stroke, multiple sclerosis, Alzheimer's disease, headache, epilepsy, pain, and somnambulism. Conversely, sleep loss has been reported to be a potential protective factor against Parkinson's disease. The pathophysiology involved in this relationship is multiple, comprising immune, neuroendocrine, autonomic, and vascular mechanisms. It is extremely important to identify the individuals at risk, since recognition and adequate treatment of their sleep problems may reduce the risk of certain neurologic disorders.

Use of actigraphy for assessment in pediatric sleep research

The use of actigraphs, or ambulatory devices that estimate sleep-wake patterns from activity levels, has become common in pediatric research. Actigraphy provides a more objective measure than parent-report, and has gained popularity due to its ability to measure sleep-wake patterns for extended periods of time in the child's natural environment. The purpose of this review is: 1) to provide comprehensive information on the historic and current uses of actigraphy in pediatric sleep research; 2) to review how actigraphy has been validated among pediatric populations; and 3) offer recommendations for methodological areas that should be included in all studies that utilize actigraphy, including the definition and scoring of variables commonly reported. The poor specificity to detect wake after sleep onset was consistently noted across devices and age groups, thus raising concerns about what is an "acceptable" level of specificity for actigraphy. Other notable findings from this review include the lack of standard scoring rules or variable definitions. Suggestions for the use and reporting of actigraphy in pediatric research are provided.

Chronic headaches and insomnia: working toward a biobehavioral model

BACKGROUND

Sleep disturbances are consistently associated with chronic headaches, yet the mechanisms underlying this relationship remain unclear. One potential barrier to generating new hypotheses is the lack of synthesis between models of headache and models of sleep. The goal of this paper is to present a perspective on the chronification of migraine and tension-type headaches based upon conceptual models used in sleep research.

METHODS

We provide a critical review of the literature on sleep and headache, highlighting the limitations in sleep methodology. Models of sleep physiology and insomnia are discussed, along with the potential implications for the chronification of migraine and tension-type headache. In addition, we propose a biobehavioral model that describes the interaction between behaviors related to coping with headache, the impact of these behaviors on insomnia and sleep physiology and the downstream propensity for future headache attacks.

CONCLUSIONS

We hope that this perspective will stimulate interdisciplinary activity toward uncovering the pathway for more effective interventions for chronic headache patients.

The assessment of sleep in pediatric chronic pain sufferers

The aim of this study is to review the options available for assessing sleep in pediatric chronic pain populations. One subjective measure of sleep (questionnaires) and two objective measures (polysomnography and actigraphy) were reviewed. The following databases were searched from their inception to June 2011: PsycINFO, ERIC, FRANCIS, MEDLINE, PsycARTICLES, Global health, Inspec, Health and Psychosocial Instruments, CINAHL, Scopus and ProQuest Dissertations and Theses databases. A total of nine sleep questionnaires were identified, two of which proved to be reliable and valid when used with pediatric chronic pain patients and, according to evidence-based assessment criteria, can be regarded as "well-established" instruments. Objective measures have been used less frequently. Both polysomnography (PSG) and actigraphy (ACT) have been used in five different studies. PSG is a reliable method for assessing sleep stage problems but is costly and intrusive. Actigraphy is cheaper, more ecological and easier to use than PSG but it deals only with the objective dimension of sleep (total sleep time, sleep efficiency, etc). In order to improve the reliability and validity of the assessment of sleep, a multi-level and multi-method approach is suggested: sleep measurement should be extended to include both objective and subjective assessment.