Relationships between headache and sleep in a non-clinical population of children and adolescents

Influence of chronotype on pain incidence during early adolescence

ABSTRACT

During adolescence major shifts in sleep and circadian systems occur with a notable circadian phase delay. Yet, the circadian influence on pain during early adolescence is largely unknown. Using 2 years of data from the Adolescent Brain Cognitive Development study, we investigated the impact of chronotype on pain incidence, moderate-to-severe pain, and multiregion pain 1 year later in U.S. adolescents. Based on the Munich ChronoType Questionnaire, chronotype was calculated as the midpoint between sleep onset and offset on free days, corrected for sleep debt over the week. Adolescents reported pain presence over the past month, and if present, rated pain intensity (0-10 numerical rating scale; ≥ 4 defined as moderate-to-severe pain) and body site locations (Collaborative Health Outcomes Information Registry Body Map; ≥2 regions defined as multiregion pain). Three-level random intercept logistic regression models were specified for each pain outcome, adjusting for baseline sociodemographic and developmental characteristics. Among 5991 initially pain-free adolescents (mean age 12.0 years, SD 0.7), the mean chronotype was 3:59 am (SD 97 minutes), and the 1-year incidence of pain, moderate-to-severe pain, and multiregion pain was 24.4%, 15.2%, and 13.5%, respectively. Each hour later chronotype at baseline was associated with higher odds of developing any pain (odds ratio [OR] = 1.06, 95% confidence interval [CI] = 1.01, 1.11), moderate-to-severe pain (OR = 1.10, 95% CI = 1.05-1.17), and multiregion pain (OR = 1.08, 95% CI = 1.02-1.14) during 1-year follow-up. In this diverse U.S. adolescent sample, later chronotype predicted higher incidence of new-onset pain.

Relationship between sleep problems and headaches among adolescents: Pelotas 2004 Birth cohort

Objective

To investigate the cross-sectional association between sleep problems (the exposure) and headaches (the outcome) among 15-year-olds from the Pelotas 2004 Birth Cohort, a population-based study in the south of Brazil.

Method

The occurrence of headaches was obtained through the question: "Do you usually suffer headaches?" and the ICHD-3 criteria were used to classify as: tension-type headache, headache with characteristics of migraine with or without aura, or other. Regarding sleep, the weekly frequency in the last month of insomnia and bad dreams/nightmares, and self-reported sleep quality were investigated. Unadjusted and adjusted prevalence ratios (PR) with 95% confidence intervals were calculated using Poisson regression with robust variance.

Results

A total of 1916 adolescents were analyzed. The prevalence of headaches was 51.6% (69.0% in females and 34.8% in males): 31.8% (39.7% vs. 24.1%) reported tension-type headache; 14.7% (21.9% vs. 7.8%), headaches with characteristics of migraines without aura; 3.6%, headaches with characteristics of migraines with aura; and 1.5% (5.1% vs. 2.3%), other types. Adolescents with insomnia ≥3 times/week presented higher probability of headaches (PR = 1.54; 95%CI 1.23-1.93), compared with those with no problems falling asleep or maintaining sleep. Among those who classified their sleep as poor/very poor, the probability of headaches was 33% higher (PR = 1.33; 95%CI 1.13-1.57) than among those who classified their sleep as very good.

Conclusions

Headaches were highly prevalent among the adolescents and were related to sleep problems even after allowing for several confounders.

Preliminary exploration of a multidimensional sleep health composite in adolescent females with frequent migraine

OBJECTIVE

This observational study aimed to: (i) describe and explore preliminary psychometric properties of a multidimensional sleep health composite score in adolescent females with frequent migraine; and (ii) examine associations between the composite score, headache characteristics, and emotional health.

BACKGROUND

Sleep health is a multidimensional construct comprised of various dimensions of sleep and circadian functioning, including Regularity, Satisfaction, Alertness, Timing, Efficiency, and Duration (Ru-SATED framework). The Ru-SATED sleep health composite score may provide a holistic perspective of sleep among adolescents with frequent migraine in the context of neurobiological and psychosocial impacts on sleep unique to this developmental period.

METHODS

In all, 60 female adolescents (aged 12-18 years) with high-frequency episodic or chronic migraine completed wrist-worn actigraphy for 10 days and concurrent daily electronic surveys assessing headache, sleep, and emotional health. A sleep health composite score was derived from empirically supported "healthy" versus "unhealthy" ratings on the six Ru-SATED sleep dimensions.

RESULTS

Half of participants (27/54 [50%]) had a composite score ≥4 (i.e., at least four of the six dimensions rated as poor). Convergent validity of the composite score was acceptable (rs = 0.30-0.56, all p < 0.05). Internal consistency among the dimensions was low (α = 0.45). Multivariate multiple regression models indicated that worse sleep health was associated with greater headache-related disability (B = 0.71, p = 0.018) and anxiety (B = 0.59, p = 0.010), and trended toward significance for sadness (B = 0.35, p = 0.052). The composite score was not significantly associated with headache frequency or severity.

CONCLUSIONS

A multidimensional sleep health composite score may provide an alternative, more comprehensive picture of sleep disturbance among adolescent females with frequent migraine. Larger studies are needed to examine psychometric properties more rigorously and further explore the composite score as a potentially unique predictor of headache outcomes.

School-based online survey on chronic headache, migraine, and medication-overuse headache prevalence among children and adolescents in Japanese one city - Itoigawa Benizuwaigani study

BACKGROUND

We investigated the prevalence of headache, migraine, and medication-overuse headache (MOH) among children and adolescents through a school-based online questionnaire. We also investigated the triggers for migraine among them and the effect of the COVID-19 pandemic on headache frequency.

METHODS

Children and adolescents aged 6-17 y.o. completed an online questionnaire. Migraine, MOH was defined as The International Classification of Headache Disorders Third edition. Factor and clustering analyses were performed for migraine triggers. The effect of the coronavirus disease 2019 (COVID-19) pandemic on headache frequency was also asked.

RESULTS

Of the 2489 respondents, the prevalence of headache, migraine, and MOH were 36.44%, 9.48%, and 0.44%, respectively. Up to 70% of the respondents with headaches complained of the disturbance to daily life, but about 30% consulted doctors. The migraine triggers were grouped into 5 factors by factor analysis. The sensitivities of the migraineurs against the factors were divided into 3 clusters. Cluster 1 had stronger sensitivity for several triggers. Cluster 2 was sensitive to weather, smartphones, and video games. Cluster 3 had less sensitivity for triggers. Cluster 2 less consulted doctors even though the burden of migraine was enormous. During the COVID-19 pandemic, 10.25% of respondents increased headache attacks, while 3.97% decreased.

CONCLUSIONS

This is the first detailed study on headache prevalence in Japanese students from elementary school to high school in one region. The burden of headaches is large among children and adolescents, and the unmet needs of its clinical practice should be corrected.

[Modern principles of primary headaches prevention in children and adolescents]

Headaches in children and adolescents are an actual problem of modern medicine. In most cases, headaches are regarded as a manifestation of vertebrogenic or cerebrovascular pathology, or as a manifestation of autonomic dystonia syndrome which leads to an erroneous diagnosis and treatment. The review considers the factors of occurrence and chronicity of primary headaches (hypodynamia, postural disorders, magnesium and vitamin D deficiency, anxiety and depression, central sensitization, alexithymia), methods for their diagnosis and treatment.

Sleep and Executive Functioning in Pediatric Traumatic Brain Injury Survivors after Critical Care

Over 50,000 children are hospitalized annually for traumatic brain injury (TBI) and face long-term cognitive morbidity. Over 50% develop sleep/wake disturbances (SWDs) that can affect brain development and healing. We hypothesized SWDs would portend worse executive function outcomes in children aged 3−18 years with TBI 1−3 months after hospital discharge. SWDs were defined using the Sleep Disturbances Scale for Children (t-scores ≥ 60). Outcomes included the Global Executive Composite (GEC, t-score) from the Behavior Rating Inventory of Executive Function, Second and Preschool Editions, and multiple objective executive function assessments combined through Principal Components Analysis into a Neurocognitive Index (NCI, z-score). Multiple linear regression evaluated associations between SWDs and executive function outcomes, controlling for covariates. Among 131 children, 68% had clinically significant SWDs, which were associated with significantly worse median scores on the GEC (56 vs. 45) and NCI (−0.02 vs. 0.42; both p < 0.05). When controlling for baseline characteristics and injury severity in multivariable analyses, SWDs were associated with worse GEC (β-coefficient = 7.8; 95% Confidence Interval = 2.5, 13.1), and worse NCI (β-coefficient = −0.4; 95% Confidence Interval = −0.8, −0.04). SWDs in children with TBI are associated with worse executive function outcomes after hospital discharge, and may serve as modifiable targets to improve outcomes.

Sleep Characteristics in the Italian Pediatric Population: A Systematic Review

OBJECTIVE

During childhood sleep duration, quality and patterns evolve and change greatly and relate strongly to healthy development. This systematic review aims to summarize the literature on sleep characteristics in the Italian pediatric population, adopting a cultural perspective.

METHOD

Pubmed, PsycINFO and Medline databases were systematically searched. Eligible studies had to: include Italian children and adolescents; report data for one or more sleep-related variables; be published in English or Italian.

RESULTS

Twenty-nine studies were selected including 18551 Italian children or adolescents. Studies were categorized by age group: infancy and toddlerhood (0-3 years); preschool and school age (3-12 years); adolescence (12-18 years) and mixed age groups. Overall, studies showed that the Italian pediatric population present shorter sleep duration and longer sleep onset latency compared to international recommendations. Furthermore, data indicate high prevalence of dysfunctional sleep habits, such as late bed-time (all age groups), involvement of parents during bed-time (infancy and toddlerhood), and high variability between sleep times on week-days vs. weekends (adolescence). Nevertheless, most studies lacked comprehensive data on sleep patterns, focusing instead on isolated variables.

CONCLUSION

These results suggest a strong trend among Italian children and adolescents towards unhealthy sleep patterns. Comprehensive data are still lacking and large studies evaluating a broad range of sleep characteristics in Italian pediatric populations are needed. Data strongly suggest that Italian Pediatric Primary Care should place higher focus on sleep problems and implement clinical protocols directed towards improving sleep patterns in children and adolescents.

Validity and reliability of the Turkish version of Sleep Disturbance Scale for Children

OBJECT

This study examines the validity and reliability of the Sleep Disturbance Scale for Children (SDSC) in the Turkish language.

METHOD

This scale was translated into the Turkish language by applying the translation-back translation method and content validity analysis. A total of 1903 participants aged 5-15 years were included in the study. A sociodemographic data form, SDSC, and the Children's Sleep Habits Questionnaire (CSHQ) were filled by the parents. Internal consistency analysis, correlation analysis, test-retest analysis, and confirmatory factor analysis were applied to evaluate the reliability and validity of the applied scale.

RESULTS

The internal consistency of the scale was high (Cronbach α = 0.84). Test-retest reliability was found to be high as well. According to the confirmatory factor analysis, the Turkish version of the scale was compatible with the model of the original scale. According to the T-score evaluation, the frequency of sleep disorders was determined to be 4.15%, and the most common sleep disorder was sleep hyperhidrosis. Correlations between the scores of the SDSC and CSHQ were at a satisfactory level.

CONCLUSIONS

These results revealed that the SDSC is a valid and reliable scale that can be used in children aged 5-14 years in Turkey to question sleep disorder symptoms.

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.

Measures of circadian preference in childhood and adolescence: A review

Purpose

To review the psychometric properties of the questionnaires commonly filled in by children and adolescents to measure circadian preference.

Methods

We examined the Morningness-Eveningness Questionnaire for Children and Adolescents (MEQ-CA), the Morningness-Eveningness Scale for Children (MESC) and the Composite Scale of Morningness (CSM). We critically analyzed the reliability, in term of internal consistency (through the Cronbach's alpha) and test-retest reliability (through the correlation coefficient), and the type of validation against external criteria (objective assessment of the sleep/wake cycle, body temperature, hormones and other questionnaires). Fifty studies that reported these data were included in the review: 7 studies used the MEQ-CA, 28 used the MESC and 15 used the CSM.

Results

The percentage of studies reporting at least acceptable levels of internal consistency was high and similar between the three questionnaires. Evidence for test-retest reliability was scant, since only 3 studies were available; it was at least acceptable for the MESC (two studies with a time interval of 1 month), not acceptable for the MEQ-CA (one study with a time interval of 6 months), while no information was available for the CSM. As regards the validation evidence, the MEQ-CA has been validated by the highest number of external criteria (actigraphy, oral body temperature and other questionnaires), followed by the CSM (cortisol sampling and other questionnaires). The MESC has been validated only against self-report measures.

Conclusions

The present state of the art would suggest the use of the MEQ-CA to assess circadian preference in children and adolescents.

The Impact of Sleep on Disability and School Functioning: Results From a Tertiary Pediatric Headache Center

Pediatric headache patients often experience significant sleep disturbance, which may be a risk factor for poor physical, academic, and emotional functioning, including increased anxiety/fear. The current retrospective cohort study of a clinical sample of youth with persistent headache aimed to examine the impact of sleep on functional outcomes and to explore pain-related fear as a mediator of the association between sleep problems and functioning. A total of 109 youth (aged 7-17 years) with persistent headache presenting to a tertiary pediatric headache center (and their parents) completed measures of sleep problems, fear of pain, functional disability, and school functioning at the time of an initial evaluation and 6 months later. After controlling for age and headache frequency and severity, linear regression analyses indicated that increased sleep problems at baseline were associated with increased functional disability and poorer school functioning at baseline (β = 0.28, P = .01; β = -0.42, P < .001, respectively). Poor sleep at baseline was associated with poorer school functioning (but not functional disability) at follow-up (β = -0.25, P = .02). Mediation models demonstrated an indirect mediating effect of pain-related fear on the association between baseline sleep problems and follow-up functional disability (β = 0.06, 95% confidence interval 0.01, 0.15) and between baseline sleep problems and follow-up school functioning (β = -0.06, 95% confidence interval -0.13, -0.004). Sleep disturbance in youth with headache may be a risk factor for poor functional outcomes, both concurrently and over time, and may be explained partially through pain-related fear. Given the frequency with which pediatric headache patients experience co-occurring sleep problems, sleep should be thoroughly assessed and considered as a potential early treatment target.

Post-traumatic Headache After Pediatric Traumatic Brain Injury: Prevalence, Risk Factors, and Association With Neurocognitive Outcomes

Post-traumatic headache is common after pediatric traumatic brain injury and affects thousands of children every year, but little is known about how headache affects recovery after traumatic brain injury in other symptom domains. We aimed to determine the association between headache and other common symptoms after pediatric traumatic brain injury and explore whether subjective complaints of headache are associated with objective deficits on specialized neurocognitive testing. We conducted a retrospective cohort study of children ages 3-19 years following traumatic brain injury with a completed Sports Concussion Assessment Tool (SCAT) questionnaire. Post-traumatic headache was defined by a score more than 2 on the SCAT question for headache and define headache groups for comparison. In our cohort, we analyzed data from the Delis-Kaplan Executive Function System and the Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II). Headache was reported in 40 (33%) patients presenting for post-traumatic brain injury care among 121 pediatric traumatic brain injury patients and did not differ by injury severity. Median total SCAT symptom score in the headache group was 5-fold higher compared to patients without headache (median 45.5 vs 9; P < .001). Significantly lower-scaled scores in color naming, matrix reasoning, letter sequencing, and letter switching were also found in the headache group (all P ≤ .03). Our study shows that headache, as reported by patients on the SCAT, is associated with higher symptom scores in all other symptom domains, including sleep, mood, sensory, and cognitive. Headache was also associated with worse objective neurocognitive measures and may identify patients who could benefit from specialized follow-up care and management.

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.

Sleep disorder-related headaches

Migraine with and without aura, cluster headache, hypnic headache, and paroxysmal hemicranias are each reported as intrinsically related to sleep. Chronic migraine, chronic tension-type headache, and medication overuse headache may cause sleep disturbance. Otherwise, both headache and sleep disorder may be manifestations of a same systemic dysfunction. There is a vicious cycle linking sleep disorders and migraine. The poor quality or poor duration of sleep could be a trigger of migraine attack and migraineurs with poor sleep reported a higher headache frequency. Moreover, coping behaviors of migraineurs (e.g., going to sleep early to relieve migraine attacks) can be factors precipitating and perpetuating sleep disturbances themselves. During cluster headache, patients report a poor quality of sleep correlated with the amount of daylight. In particular, it was demonstrated that melatonin levels have influences on cluster headache attacks. Concerning the pathophysiology of hypnic headache, it has been hypothesized a possible role of obstructive sleep apnea in triggering nocturnal attacks: an increased number of apnea episodes has been reported in hypnic headache patients, but a lack of a temporal correlation of headache attacks with the drop of oxygen saturation has been observed. Tension-type headache is the most common headache with sleep dysregulation (lack of sleep or oversleeping) frequently reported as a triggering factor for acute attacks: management of sleep disturbances seems crucial in this form of headache.

Clinical presentation, diagnosis and polysomnographic findings in children with migraine referred to sleep clinics

OBJECTIVE

An association between migraine and sleep disturbances in children was reported, yet limited clinical data exist. The current study addresses the clinical presentation, polysomnographic (PSG) characteristics, and comorbid sleep diagnoses of children with migraine referred to the sleep clinic.

PATIENTS

A retrospective review was performed of headache center patients evaluated by the sleep center between 2007 and 2017. Children ≤18 years old, diagnosed with migraine headache, and who had PSG within one year of evaluation in the headache clinic, were included. PSG findings, as well as demographics, were compared to a group of controls aged 5-14 years-old.

RESULTS

In sum, 185 children with a diagnosis of migraine were included: 39% males, 75% Caucasian, mean age 13.5 ± 3.4, and 57% obese. Additionally, 180 children were included in the control group. The common presenting sleep symptoms were snoring (66%), sleep onset and sleep maintenance problems (25%), and excessive daytime sleepiness (20%). For the sleep diagnosis, 40% had obstructive sleep apnea (OSA), 27% had insomnia, 15% had periodic limb movement disorder (PLMD), and 6% had a central disorder of hypersomnolence. In terms of sleep architecture, children with migraine had significantly higher NREM 2 (p < 0.001) and a lower percentage of NREM3 (p < 0.001) compared to controls after adjustment for demographics and the presence of sleep-disordered breathing.

CONCLUSIONS

Children referred to the sleep clinic who also had migraine, experience various types of sleep complaints. OSA, insomnia, and PLMD were relatively common in this population. Changes in sleep architecture, specifically increased NREM2 and decreased slow wave sleep compared to the control group, were also observed.

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.

More than just sleeping in: a late timing of sleep is associated with health problems and unhealthy behaviours in adolescents

OBJECTIVE

New research suggests that the timing of sleep, or chronotype, affects the mental well-being of adolescents, however evidence of its links to physical health is limited. We investigated the associations between chronotype and various health outcomes and behaviours in a national sample of Canadian adolescents.

METHODS

Data were from the 2014 Canadian Health Behaviour in School-Aged Children survey (29,470 students; ages 10-18). Chronotype was estimated using the midpoint of sleep on weekends, corrected for catch-up sleep. We tested the associations with physical health (headache, stomach ache, back ache, dizziness, overweight, self-rated health) and health behaviours (consumption of fruits, vegetables, sweets, soft drinks, and energy drinks, smoking, physical activity, screen time) using random-effects regressions adjusted for sleep duration and individual, family, and school characteristics.

RESULTS

The average chronotype was 4:11 a.m. for boys and 4:10 for girls. Each 1-h delay in chronotype was associated with more headaches, stomach aches, and back aches [proportional odds ratios (PropORs) 1.08, 1.08, 1.07, respectively (boys), 1.10, 1.10, 1.08, respectively (girls)], and dizziness and worse self-rated health in girls (PropORs 1.10 and 1.09, respectively), but not overweight. A 1-h delay in chronotype also related to daily soft drink consumption [ORs 1.17 (boys), 1.11 (girls)], smoking [ORs 1.23 (boys), 1.37 (girls)], screen time [additional 0.64 h (boys), 0.74 h (girls)], less vegetable consumption in boys (OR 0.96), and daily energy drink consumption in girls (OR 1.42).

CONCLUSION

A later chronotype related to worse physical health and unhealthy behaviours in Canadian adolescents. Studies are needed to clarify the underlying mechanisms.

The Sleep Hygiene Inventory for Pediatrics: Development and Validation of a New Measure of Sleep in a Sample of Children and Adolescents With Chronic Headache

Sleep plays a pivotal role in children and adolescents with headache. Although several sleep measures exist, no developed measures target the sleep issues common in pediatric patients with headache. The Sleep Hygiene Inventory for Pediatrics (SHIP) was developed for clinical purposes to fulfill this need. The aim of this study was to validate the SHIP for potential research applications in a sample of 1078 children and adolescents (7-17 years) with a primary headache diagnosis. Measure validation included assessments of internal consistency, construct validity, and criterion validity. The SHIP demonstrated strong internal consistency (Cronbach α = 0.84). The SHIP differentiated well between participants for whom sleep was and was not a clinical concern ( P < .001; d =1.65), and was positively correlated with anxiety, depression, and disability. These analyses suggest that the SHIP is a psychometrically strong and valid assessment of sleep habits in pediatric patients with headache.

The role of attachment insecurity in the emergence of anxiety symptoms in children and adolescents with migraine: an empirical study

Background

It is widely recognised that there are associations between headache, psychiatric comorbidity and attachment insecurity in both adults and children. The aims of this study were: 1) to compare perceived attachment security and anxiety in children and adolescents with migraine without aura and a healthy control group; 2) to test whether the child’s perceived security of attachment to the mother and the father mediated the association between migraine and anxiety.

Methods

One hundred children and adolescents with Migraine without Aura were compared with a control group of 100 children without headache. The Security Scale (measures perceived security of attachments) and the Self-Administered Psychiatric Scales for Children and Adolescents, a measure of anxiety symptoms, were administered to all participants.

Results

The clinical group had lower attachment security than the control group and higher scores on all anxiety scales. Anxiety was negatively correlated with attachment. Children’s attachment to their mother mediated the increase in global anxiety in the clinical group. Insecure paternal attachment was associated with greater insecurity in maternal attachment, suggesting that there is a complex pathway from migraine to anxiety symptoms mediated by perceived insecurity of paternal attachment and hence also by perceived insecurity of maternal attachment.

Conclusion

These results suggest that insecure parental attachment may exacerbate anxiety in children and adolescents with migraine and point to the importance of multimodal interventions, perhaps taking account of family relationships, for children and adolescents with migraine.

Chronic Daily Headache in Children and Adolescents: A Multi-Faceted Syndrome

Chronic daily headache (CDH) is a multi-faceted, often complex pain syndrome in children and adolescents. Chronic daily headache may be primary or secondary. Chronic migraine and chronic tension-type are the most frequent subtypes. Chronic daily headache is co-morbid with adverse life events, anxiety and depressive disorders, possibly with other psychiatric disorders, other pain syndromes and sleep disorders; these conditions contribute to initiating and maintaining CDH. Hence, early management of episodic headache and treatment of associated conditions are crucial to prevention. There is evidence for the benefit of psychological therapies, principally relaxation and cognitive behavioral, and promising information on acupuncture for CDH. Data on drug treatment are based primarily on open label studies. The controversies surrounding CDH are discussed and proposals for improvement presented. The multifaceted nature of CDH makes it a good candidate for a multi-axial classification system. Such an approach should facilitate biopsychosocial management and enhance consistency in clinical research.

Quality of life, sleepiness and depressive symptoms in adolescents with insomnia: A cross-sectional study

Objectives

To determine the prevalence of insomnia in a sample of Portuguese adolescents and assess its repercussions on HRQoL, daytime sleepiness and depressive symptomatology.

Design

We carried out a cross-sectional school-based study evaluating students from Viseu.

Location

Students from twenty-six public secondary schools in the county of Viseu, Portugal.

Participants

Of 9237 questionnaires distributed, 7581 were collected (82.1%). We excluded from analysis all questionnaires from adolescents younger than 12 or older than 18 years of age (211) and unfilled forms (451). The sample comprised 6919 adolescents, the 7th to 12th grade, from 26 public secondary schools.

Interventions

None.

Measurements

Data gathering was done using a self-applied questionnaire. Insomnia was defined based on the Diagnostic and Statistical Manual of Mental Disorders – IV criteria. HRQoL was evaluated with the Quality of Life Health Survey SF-36, depressive symptomatology with BDI-II and daytime sleepiness with the Epworth Sleepiness Scale.

Results

Prevalence of insomnia was 8.3% and the prevalence of adolescents with symptoms of insomnia without daytime impairment (disturbed sleepers) was 13.1%. HRQoL was significantly reduced among adolescents with insomnia compared to normal sleepers (p < 0.001) and even when compared to disturbed sleepers (p < 0.001). There was an increase in daytime sleepiness from normal sleepers to disturbed sleepers and to adolescents with insomnia (p < 0.001). There was also an increase in the prevalence and severity of depressive symptoms (p < 0.001).

Conclusions

Our results show that insomnia is associated with a significantly lower health related quality of life among adolescents.

Relationship Between Short Sleep Duration and Preseason Concussion Testing

OBJECTIVE

Baseline, preseason assessment of cognition, symptoms, and balance has been recommended as part of a comprehensive sport concussion management program. We examined the relationship between sleep and baseline test results. We hypothesized that adolescents who slept fewer hours the night before would report more symptoms and perform more poorly on cognitive testing than students who had a full night sleep.

DESIGN

Cross-sectional observation study.

SETTING

Preseason concussion testing for high school athletes.

PARTICIPANTS

A large sample (n = 2928) of student athletes from Maine, USA, between the ages of 13 and 18 years completed preseason testing. Participants with developmental problems, a history of treatment for neurological or psychiatric problems, recent concussion, or 3 or more prior concussions were excluded.

ASSESSMENT OF RISK FACTORS

Athletes were divided into 4 groups based on their sleep duration the night before testing.

MAIN OUTCOME MEASURES

Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT; ImPACT Applications, Inc, Pittsburgh, PA) cognitive composite scores and the embedded Post-Concussion Symptom Scale.

RESULTS

Sleep was not related to any ImPACT cognitive composite score, after covarying for age and controlling for multiple comparisons. In contrast, there were sleep duration, sex, and sleep duration by sex effects on the Post-Concussion Symptom Scale. The effect of sleep duration on symptom reporting was more pronounced in girls. Supplementary analyses suggested that sleep insufficiency was associated with a diverse array of postconcussion-like symptoms.

CONCLUSIONS

Poor sleep the night before baseline or postinjury testing may be an important confound when assessing postconcussion symptoms. Girls may be more vulnerable to experiencing and reporting symptoms following insufficient sleep.

CLINICAL RELEVANCE

Clinicians should routinely ask how the athlete slept the night before preseason baseline testing and consider deferring the symptom assessment or later retesting athletes who slept poorly.

Associations Between Sleep Quality and Migraine Frequency: A Cross-Sectional Case-Control Study

Migraine has been associated with sleep disturbances. Relationship between sleep quality and migraine frequency is yet to be determined. The present study aimed to investigate sleep disturbances among low-frequency, moderate-frequency, high-frequency, and chronic migraineurs, with and without auras, with well-controlled confounding variables.This cross-sectional controlled study included 357 subjects from an outpatient headache clinic in Taiwan. Standardized questionnaires were utilized to collect demographic, migraine, sleep, depression, anxiety, and restless leg syndrome characteristics in all participants. According to frequency of migraine attacks, patients were divided into 4 groups: with 1 to 4 migraine days per month, 5 to 8 migraine days in a month, 9 to 14 migraine days in a month, and >14 migraine days per month. The Pittsburgh Sleep Quality Index (PSQI) and subgroup items were used to evaluate sleep quality. The association between migraine frequency and sleep quality was investigated using multivariable linear regression and logistic regression.The PSQI total score was highest in patients with high frequent migraine (10.0 ± 3.4) and lowest in controls (7.0 ± 3.4) with a significant trend analysis (P for trend = 0.006). Migraine frequency had an independent effect on the items "Cannot get to sleep within 30 minutes" (P < 0.001), "Wake up in the middle of the night or early morning" (P < 0.001), "Bad dreams" (P = 0.001), "Pain" (P = 0.004), and "Quality of sleep" (P < 0.001). The result showed the effect of migraine frequency in both the aura-present (P for trend = 0.008) and the aura-absent subgroups (P for trend = 0.011).High migraine frequency correlates with poor sleep quality and a higher prevalence of poor sleepers. These associations occur in migraine with aura and without aura.

Risk of Restless Legs Syndrome Following Tension-Type Headache: A Nationwide Population-Based Cohort Study

Migraine and restless legs syndrome (RLS) appear to be associated, but the relationship between tension-type headache (TTH) and RLS is unknown. This nationwide, population-based, retrospective cohort study explored the potential association between TTH and RLS.We identified 15,504 patients with newly diagnosed TTH from 2000 to 2007 and 62,016 individuals without TTH who were selected by frequency matched based on sex, age, and the index year. The study participants were followed until diagnosed with RLS, withdrawal from the NHI program, or the end of 2011. Cox proportional hazard models were used to identify risk factors for RLS in TTH patients.After adjusting for sex, age, comorbidity, and medications, TTH was significantly associated with an increased risk of RLS (hazard ratio [HR] = 1.57, 95% confidence interval [CI] = 1.22-2.02). The risk was most prominent in patients aged 20 to 39 years in the TTH group, which exhibited a 2.60-fold higher risk (95% confidence interval = 1.53-4.42) of RLS compared with the non-TTH group. The TTH group had a higher risk of RLS than that of the non-TTH group regardless of sex.Tension-type headache appears to be associated with an increased risk of developing RLS. This similarity to migraines may indicate that headache and RLS have a coincident pathophysiological mechanism, a possibility requiring further study. Clinicians should be more attentive to RLS as a possible comorbidity in patients with TTH.

Migraine and tension-type headache triggers in a Greek population

Migraine and tension type headache are the two most common primary headaches. The purpose of this study was to detect differences in clinical characteristics and headache triggers and in a Greek cohort of 51 migraineurs and 12 patients with tension-type headache. (TTH) Migraine patients had a significantly lower age at headache onset and frequency, higher mean visual analogue scale (VAS) and greater maximum duration of headache episodes compared to TTH patients. They did not differ from (TTH) patients in quality of headache, laterality of pain, way of headache installation and progression and temporal pattern of headaches. Nausea, vomiting and phonophobia were more frequent in migraine. Triggering of headaches by dietary factors was associated with migraine, whereas there was no difference between the two groups in any of the other headache triggers. Stress, both physical and psychological, were particularly common in both patient groups.

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.

Headache in school age

Headache, especially migraine and tension-type headache, is one of the most frequently reported somatic complaints by children and adolescents. Different population-based studies have been conducted to study the correlation between headache and lifestyles in pediatric age, nevertheless, the obtained results are often controversial and these relationship still remain unclear. Likewise, is still strongly debated the burden of headache during school age, its impact on school performances and on quality of life of children and their families. Consequently, larger studies are necessary to evaluate the degree of disability due to pediatric headache. We summarize the ongoing knowledge about these concepts, with the intent to provide useful data to neurologists but also to primary care providers, to further improve the management of pediatric headaches by preventing the headache progression, the disabling effects associated and improving the long-term outcome.

Urinary 6-sulphatoxymelatonin levels and sleep disorders in children with migraine

We conducted the present study to assess melatonin secretion in a sample of children with migraine, to describe their sleep patterns and problems, and to examine the impact of sleep problems on migraine disability. The parents of 18 children with migraine completed the Children's Sleep Habits Questionnaire and Pediatric Migraine Disability Assessment Score in Arabic. The parents of 18 healthy controls also completed the Children's Sleep Habits Questionnaire. Urinary 6-sulphatoxymelatonin levels were determined with the enzyme-linked immunosorbent assay method. There was no significant difference in urinary 6-sulphatoxymelatonin between the migraine and control groups (Z = -0.127, P = .889). There were no significant differences between groups in Children's Sleep Habits Questionnaire subscales or total scores. There were significant correlations between bedtime resistance, parasomnias subscales, and migraine disability. Our findings indicate that nocturnal production of melatonin is not reduced in children with migraine, and sleep disturbances impact the degree of migraine disability.

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.

The relationship between migraine and infant colic: a systematic review and meta-analysis

CONTEXT

Infant colic is a common and distressing disorder of early infancy. Its etiology is unknown, making treatment challenging. Several articles have suggested a link to migraine.

OBJECTIVE

The objective of this article was to perform a systematic review and, if appropriate, a meta-analysis of the studies on the relationship between infant colic and migraine.

DATA SOURCES

Studies were identified by searching PubMed and ScienceDirect and by hand-searching references and conference proceedings.

STUDY SELECTION

For the primary analysis, studies specifically designed to measure the association between colic and migraine were included. For the secondary analysis, studies that collected data on colic and migraine but were designed for another primary research question were also included.

DATA EXTRACTION

Data were abstracted from the original studies, through communication with study authors, or both. Two authors independently abstracted data.

MAIN OUTCOMES AND MEASURES

The main outcome measure was the association between infant colic and migraine using both a fixed-effects model and a more conservative random-effects model.

RESULTS

Three studies were included in the primary analysis; the odds ratio for the association between migraine and infant colic was 6.5 (4.6-8.9, p < 0.001) for the fixed-effects model and 5.6 (3.3-9.5, p = 0.004) for the random-effects model. In a sensitivity analysis wherein the study with the largest effect size was removed, the odds ratio was 3.6 (95% CI 1.7-7.6, p = 0.001) for both the fixed-effects model and random-effects model.

CONCLUSIONS

In this meta-analysis, infant colic was associated with increased odds of migraine. If infant colic is a migrainous disorder, this would have important implications for treatment. The main limitation of this meta-analysis was the relatively small number of studies included.

Pharmacoinformatics elucidation of potential drug targets against migraine to target ion channel protein KCNK18

Migraine, a complex debilitating neurological disorder is strongly associated with potassium channel subfamily K member 18 (KCNK18). Research has emphasized that high levels of KCNK18 may be responsible for improper functioning of neurotransmitters, resulting in neurological disorders like migraine. In the present study, a hybrid approach of molecular docking and virtual screening were followed by pharmacophore identification and structure modeling. Screening was performed using a two-dimensional similarity search against recommended migraine drugs, keeping in view the physicochemical properties of drugs. LigandScout tool was used for exploring pharmacophore properties and designing novel molecules. Here, we report the screening of four novel compounds that have showed maximum binding affinity against KCNK18, obtained through the ZINC database, and Drug and Drug-Like libraries. Docking studies revealed that Asp-46, Ile-324, Ile-44, Gly-118, Leu-338, Val-113, and Phe-41 are critical residues for receptor–ligand interaction. A virtual screening approach coupled with docking energies and druglikeness rules illustrated that ergotamine and PB-414901692 are potential inhibitor compounds for targeting KCNK18. We propose that selected compounds may be more potent than the previously listed drug analogs based on the binding energy values. Further analysis of these inhibitors through site-directed mutagenesis could be helpful for exploring the details of ligand-binding pockets. Overall, the findings of this study may be helpful for designing novel therapeutic targets to cure migraine.

Prevalence of bruxism in children with episodic migraine--a case-control study with polysomnography

Background

Parents of children with migraine have described a higher prevalence of sleep bruxism and other sleep disturbances in their children. The objective of this study was to use polysomnography to investigate the prevalence of bruxism during sleep in children with episodic migraine relative to controls.

Findings

Controls and patients were matched by sex, age, years of formal education, presence of snoring, arousals per hour, and respiratory events per hour.

A total of 20 controls, between 6 and 12 years old, with no history of headache, recruited from public schools in Sao Paulo between 2009 and 2012, and 20 patients with episodic migraine recruited from the Headache Clinic at the Federal University of Sao Paulo between 2009 and 2012 underwent polysomnography.

No intervention was performed before sleep studies.

Among migraine patients, 27.5% experienced aura prior to migraine onset. The sleep efficiency, sleep latency, REM sleep latency, arousals per hour, percentage of sleep stages, and breathing events per hour were similar between groups. Five children (25%) with episodic migraine exhibited bruxism during the sleep study while this finding was not observed in any control (p = 0.045).

Conclusions

Our data demonstrate that bruxism during sleep is more prevalent in children with episodic migraine. Further prospective studies will help elucidate the underlying shared pathogenesis between bruxism and episodic migraine in children.

Headache and sleep in children

Several scientific studies report a close relationship between sleep and headache: sleep changes may reflect the onset and increase of both duration and frequency of headache attacks. Variations in sleep architecture, together with a poor sleep hygiene in children, may indeed be responsible for the onset of headache and its development into a chronic disease. For a correct clinical management of children with headache, it is therefore fundamental to investigate their sleep habits, architecture and potential disturbances, in order to develop adequate therapeutic plans for both sleep and headache.

The Association between Sleep and Injury among School-Aged Children in Iran

Background. A good night's sleep plays a key role in diseases resistance, injury prevention, and mood stability. The objective of this study was to examine relationship between sleep problems and accidental injury occurrences in school-aged children. Method. A retrospective study was conducted for comparing two groups of children. Children who have experienced injuries for at least two times during an academic year are the participants in the injury group (IG) and those who have not experienced any kind of injuries are placed in the noninjury group (NIG). Data was collected through parent-reported sleep patterns and problems using Children's Sleep Habits Questionnaire (CSHQ). Findings. The findings showed that global sleep problems were more in the IG than in the NIG. Multivariate logistic regression analysis showed that the daytime sleepiness and sleep duration are the two major reasons for accidental injury. In addition, significant difference was seen between the sleep patterns of the two groups. Sleep duration was also shorter in the IG, and this group had a greater percentage (63% versus 41.1%) of “short sleepers” (<9 h). Conclusion. There is a significant relationship between injury occurrence and sleep problems and sleep duration in Iranian school-aged children.

Migraine and periodic limb movement disorders in sleep in children: a preliminary case-control study

BACKGROUND

The relationships between sleep and headaches are complex and manifold. About the variety of phenomena that can disrupt the sleep macrostructure and can impact its restorative function, the periodic limb movements disorder (PLMd) can be considered as the most powerful.No studies are known about the role of PLMd in the pathophysiology of migraine in children.Aim of study is to assess the prevalence of PLMd and migraine and their relationship with disability and pain intensity in a pediatric sample, referred for migraine without aura by pediatricians.

METHODS

After a preliminary sleep habits screening with the Sleep Disturbances Scale for Children, 34 migraine subjects affected by migraine without aura (20 M, 14 F) (mean age 9.08; SD ± 2.28) and 51 volunteers healthy children (28 M, 23 F) (mean age 9.37; SD ± 1.81) accepted to underwent overnight PSG recordings in the Sleep Laboratory of the Clinic of Child and Adolescent Neuropsychiatry, in order to define the macrostructural sleep characteristics and the prevalence of PLMd. Subsequently, the migraineurs sample was studied in order to define the relationship between disability, pain intensity, therapeutical responsiveness and the presence of PLMd.

RESULTS

In the migraineurs children group, the individuals with PLM pathological index (PLMI ≥ 5) represent the 26.47% of sample and present higher frequency (p < 0.001), intensity (p < 0.001), duration (p = 0.006) and life impairment as scored in the PedMIDAS (p < 0.001) of headache and lower efficacy of prophylactic (p = 0.001) and acute (p = 0.006) pharmacological treatment than MoA children without PLM pathological index.

CONCLUSIONS

This preliminary study indicates the potential value of the determination of the PLMd signs, and the importance of the PSG evaluation in children affected by migraine, particularly when the clinical and pharmacological management tend to fail in the attacks control.

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.

Migraine and sleep disorders

The burden of migraine strongly increases, considering its linkage with sleep disorders. Migraine is positively associated with many sleep-complaint disorders; some are confirmed by several studies, such as restless leg syndrome, whereas others still remain uncertain or controversial, e.g. narcolepsy. Many studies have investigated the association between headache and other sleep disturbances such as daytime sleepiness, insomnia, snoring and/or apnea, but only a few have focused on migraine. Highlighting the comorbidity between migraine and sleep disorders is important to improve treatment strategies and to extend the knowledge of migraine pathophysiology.

Relationship between sleep and pain in adolescents with juvenile primary fibromyalgia syndrome

STUDY OBJECTIVES

To investigate sleep quality in adolescents with juvenile primary fibromyalgia syndrome (JPFS) and determine whether sleep abnormalities, including alpha-delta sleep (ADS), correlate with pain intensity. We hypothesized that successful treatment for pain with exercise therapy would reduce ADS and improve sleep quality.

DESIGN

Single-center preintervention and postintervention (mean = 5.7 ± 1.0 weeks; range = 4.0-7.3 weeks) observational study.

PATIENTS

Ten female adolescents (mean age = 16.2 ± 0.65 SD yr) who met criteria for JPFS and completed treatment.

INTERVENTIONS

Multidisciplinary pain treatment, including intensive exercise therapy.

MEASUREMENTS AND RESULTS

Pain and disability were measured by a pain visual analog scale (VAS) and the functional disability inventory. Subjective sleep measures included a sleep VAS, an energy VAS, and the School Sleep Habits Survey. Objective sleep measures included actigraphy, polysomnography (PSG), and the Multiple Sleep Latency Test. Baseline PSG was compared with that of healthy age- and sex-matched control patients. At baseline, patients had poorer sleep efficiency, more arousals/awakenings, and more ADS (70.3% of total slow wave sleep [SWS] versus 21.9% SWS, P = 0.002) than controls. ADS was unrelated to pain, disability, or subjective sleep difficulty. After treatment, pain decreased (P = 0.000) and subjective sleep quality improved (P = 0.008). Objective sleep quality, including the amount of ADS, did not change.

CONCLUSIONS

Although perceived sleep quality improved in adolescents with JPFS after treatment, objective measures did not. Our findings do not suggest exercise therapy for pain improves sleep by reducing ADS, nor do they support causal relationships between ADS and chronic pain or subjective sleep quality.

Morning types are less sensitive to pain than evening types all day long

BACKGROUND

Diurnal variations in pain have been observed in experimental protocols, post-surgery states and pathological conditions. Chronotype is considered to have the most profound effect on diurnal variations, and in addition, previous studies suggest that evening types may be more vulnerable to pain than morning types. This study aimed to examine whether or not morning and evening chronotypes differ in terms of their daily levels and diurnal fluctuations of pain sensitivity.

METHODS

A total of 16 morning-healthy and 15 evening-healthy men were selected using the Morningness-Eveningness Questionnaire and underwent nine measurements during 1 day (between 08:15 and 20:15 h), each consisting of five heat stimuli situated at the ventral side of the wrist.

RESULTS

A marked difference between chronotypes was found, with morning types showing less sensitivity to pain than evening types all day long [M = 50.1; standard error (SE) = 1 and M = 47.2; SE = 1, respectively; pain thresholds in centigrade]. Diurnal variations in pain were not statistically significant.

CONCLUSIONS

The results showed that chronotype could be an important factor determining sensitivity to pain, regardless of time of day.

Noisy and individual, but doable: shift-work research in humans

Working around the clock is common for many occupations, as diverse as nurses, truck drivers, physicians, steel workers, and pilots. Each shift-work profession is individual in more aspects than just work hours and individual work scenarios, each posing a different impact on the health of workers. Related health problems in shift workers, therefore, are also diverse and encompass sleep problems, metabolic and cardiovascular system disturbances, as well as cancer. Little is known about how all these individual factors influence a shift worker's health status, partly because many shift-work studies show inconsistent results. In addition, these individual factors create many methodological difficulties for researchers who investigate such work scenarios. This chapter presents examples from our laboratory and field studies of shift workers, which emphasize the importance of taking individual circumstances into account. Both study approaches, laboratory and field based, are needed to fully account for the difficulties that shift-work studies pose on both workers and researchers. Finally, understanding the mechanisms that underpin interindividual differences in response to shift work will advance our understanding of how to design better and healthier shift-work schedules in the future.

Hypersomnia in children affected by migraine without aura: a questionnaire-based case-control study

BACKGROUND

The relationship between sleep and headache is meaningful and complex. Children affected by migraines tend to show many sleep disorders, such as insufficient sleep duration and excessive daytime somnolence. Therefore, the aim of this study is to assess the rate of reported sleep habits and self-reported sleepiness in a large pediatric sample of individuals affected by migraine without aura (MoA).

METHODS

The study population consisted of 271 children aged between 6 and 13 years affected by MoA. The control group was composed of 305 typically developing children. To assess the sleep habits of all individuals (MoA and control), parents filled out the Sleep Disturbance Scale for Children, and to check the degree of subjective perceived daytime sleepiness, all subjects were administered the Pediatric Daytime Sleepiness Scale.

RESULTS

The two study groups were matched for age (P = 0.124), sex distribution (P = 0.775), and body mass index z-score (P = 0.107). Parents of children affected by MoA reported a higher total score of sleep disorder symptoms (P <0.001), disorders of initiating and maintaining (P < 0.001), and disorders of arousal (P < 0.001) than did parents of controls. No significant differences were found in disorders of excessive somnolence. Conversely, in the Pediatric Daytime Sleepiness Scale, migraine children had higher scores (24.67 ± 3.19 vs 11.94 ± 4.81; P < 0.001) and a reduction in referred total sleep time mean duration (469.83 ± 98.112 vs 527.94 ± 83.02; P < 0.001) than typically developing children.

CONCLUSION

Our study identified differences in sleep habits and found a high prevalence of daytime somnolence in children affected by MoA, suggesting the need for routine sleep screening in the pediatric management of children with migraines.