Sleep-disordered breathing does not affect nocturnal dipping,as assessed by pulse transit time,in preschool children: evidence for early intervention to prevent adverse cardiovascular effects?

ObjectiveSleep-disordered breathing (SDB) is associated with reduced nocturnal dipping of blood pressure (BP) and sleep disruption in adults, and these features confer an increased risk of cardiovascular events. As SDB prevalence in children peaks during the preschool years, we investigated nocturnal dipping and sleep fragmentation in preschool children with SDB.MethodsChildren (3–5 years; n = 163) grouped by obstructive apnoea hypopnoea index (OAHI): control, no snoring history and OAHI ⩽1 event/h; primary snoring, OAHI ⩽1 event/h; mild SDB, >1–⩽5 events/h; moderate–severe SDB, >5 events/h. Pulse transit time (PTT), an inverse continuous indicator of BP changes, and heart rate (HR) during total sleep time and the first period of rapid eye movement (REM), non-REM (NREM)1/2 and NREM3/4 sleep were expressed as percentage change from wake before sleep onset. The sleep fragmentation index (SFI) was calculated as the number of sleep stage transitions or awakenings per hour of sleep.ResultsThere were no group differences in the change in PTT or HR from wake to total sleep time or to individual sleep stages or in the proportion of children in the quartile with the smallest change in PTT during total sleep. Children with moderate–severe SDB had higher SFI than primary snoring (PS) or mild SDB groups (p < 0.05 for both) and controls (p = 0.07).ConclusionsIn contrast to adults, nocturnal dipping is preserved in young children with SDB, despite increased sleep fragmentation. As there is evidence that nocturnal dipping is similarly preserved at the school age, childhood may pose a window of opportunity for resolution of SDB when the cardiovascular effects are less marked.     

Long-term changes in heart rate variability in elementary school–aged children with sleep-disordered breathing

ObjectiveSleep-disordered breathing (SDB) in adults and children has been associated with reduced heart rate variability (HRV) indicative of autonomic dysfunction, which in turn is associated with an increased risk for cardiovascular morbidity. However, the long-term effects of pediatric SDB that has either resolved or remains unresolved on HRV are unknown.MethodsForty Children with previously diagnosed SDB and 20 non snoring controls underwent repeat overnight polysomnography (PSG) four years after the original diagnosis. At follow-up, children aged 11 to 16 years were categorized into resolved (absence of snoring and obstructive apnea hypopnea index [OAHI] ⩽ 1) or unresolved (continued to snore or had an OAHI > 1) groups. HRV was assessed using power spectral analysis for each sleep stage.ResultsThere were no group differences in age, sex or body mass index (BMI) z score. Both the resolved and unresolved SDB groups showed significant improvement in OAHI. The control, resolved, and unresolved groups all showed a significant reduction in total power (P < .001), low-frequency (LF) power (P < .05), high-frequency (HF) power (P < .001), and an increase in the LF/HF ratio (P < .001) from baseline to follow-up in all sleep stages.ConclusionsHRV did not differ between non snoring children and children with resolved and unresolved SDB four years after initial diagnosis, concomitant with a significant reduction in OAHI in both SDB groups. All groups demonstrated a decrease in HRV from baseline to follow-up which may reflect an age-related phenomenon in these children.     

Improvement of sleep-disordered breathing in children is associated with a reduction in overnight blood pressure

ObjectiveChildhood sleep-disordered breathing (SDB) is associated with elevated blood pressure (BP); however, little is known about the long-term outcomes in this population. We aimed to assess long-term changes in overnight BP in children with SDB.MethodsForty children with previously diagnosed SDB and 20 nonsnoring control participants underwent repeat overnight polysomnography (PSG) with continuous BP measurement 4 years after the original diagnosis. At follow-up, children aged 11–16 years were categorized into 2 groups of resolved (absence of snoring and obstructive apnea–hypopnea index [OAHI]⩽1) or unresolved (continued to snore or had an OAHI >1) SDB.ResultsThere were no group differences in age, sex, or body mass index (BMI) z score. OAHI was lower at follow-up (P < .05) in both the resolved (n = 18) and unresolved (n = 22) groups. BP was elevated during wake and sleep in both SDB groups compared to the control group at baseline (P < .01 for all), but it decreased by 5–15 mmHg at follow-up during sleep for both SDB groups (P < .05 for all). BP during wake was unchanged in the SDB groups at follow-up but increased in the control group (P < .05). At follow-up, BP did not differ between the control group and the SDB groups during wake or sleep. Improved oxygen saturation (SpO₂) during sleep was a significant predictor of a reduction in BP.ConclusionsSDB improved over the 4-year follow-up and both resolved and unresolved groups exhibited a significant reduction in BP during sleep, with levels similar to the control group. Our study highlights the fact that even small improvements can improve the cardiovascular effects of SDB.     

Cardiac systolic function in Greek children with obstructive sleep-disordered breathing

BackgroundObstructive sleep-disordered breathing (SDB) in children has been associated with increased ventricular strain and decreased left ventricle (LV) diastolic function. The aim of this study was to assess systolic myocardial function in children with SDB of variable severity.MethodsChildren who were referred for polysomnography during the study period underwent echocardiography (two-dimensional, Doppler and tissue Doppler imaging).ResultsA total of 46 subjects (age 6.4 ± 2.6 years) were recruited. Fourteen of them had moderate-to-severe SDB (obstructive apnea-hypopnea index (OAHI): 16.6 ± 11.6 episodes/h), 13 children had mild SDB (OAHI: 3.1 ± 0.7 episodes/h) and 19 subjects had primary snoring (OAHI: 1.2 ± 0.6 episodes/h). Children with moderate-to-severe SDB had significantly lower LV shortening fraction (SF) and ejection fraction (EF) than subjects with primary snoring (p < 0.05). SF in moderate-to-severe SDB, mild SDB and primary snoring groups was: 34.3 ± 5.5%, 36.9 ± 3.2% and 37.7 ± 4.4%, respectively, and EF: 66.9 ± 7.9%, 71.7 ± 6.4% and 72.3 ± 5.9%, respectively. OAHI, age, and systolic blood pressure were significant predictors of SF and EF (p < 0.01).ConclusionsIn children with obstructive SDB, LV systolic function is inversely associated with severity of intermittent upper airway obstruction during sleep.     

Long-term changes in blood pressure control in elementary school-aged children with sleep-disordered breathing

ObjectiveIn adults sleep-disordered breathing (SDB) has been associated with impaired baroreflex control of blood pressure (BP), which has been linked to increased cardiovascular morbidity. In children, the long-term effects of SDB on baroreflex sensitivity (BRS) and BP variability (BPV) are unknown.MethodsChildren previously diagnosed with SDB (n = 40) and 20 nonsnoring controls aged 11–16 y underwent overnight polysomnography with continuous BP measurement, four years after the original diagnosis. At follow-up, SDB was categorized as resolved (absence of snoring and obstructive apnea hypopnea index (OAHI) ⩽ 1) or unresolved (continued to snore or had an OAHI > 1). BRS and BPV were calculated using cross-spectral analysis and power spectral analysis, respectively.ResultsOnly children with resolved obstructive sleep apnea (OSA) at follow-up demonstrated an increase in BRS from 9.7 ± 3 (ms mmHg⁻¹) at baseline to 11.8 ± 4 (ms mmHg⁻¹) at follow-up (P = .03). However, children with all severities of both resolved and unresolved SDB showed a significant decrease in BPV from baseline to follow-up (a decrease in total power BPV (P < .05) and a shift in BPV spectra away from respiratory-related frequencies (increased low-frequency/high-frequency [LF/HF] ratio, P < .01). The change in OAHI was the sole determinant of change in BRS, HF power, and LF/HF ratio.ConclusionsImprovement in SDB was associated with improved BP control, regardless if SDB was treated or spontaneously resolved four years after initial diagnosis. Our findings highlight the importance of monitoring children to ensure improvement of SDB and reduce the risk for cardiovascular morbidity in the future.     

Impaired blood pressure control in children with obstructive sleep apnea

BackgroundObstructive sleep apnea (OSA) in adults has been associated with hypertension, low baroreflex sensitivity (BRS), a delayed heart rate response to changing blood pressure (heart period delay [HPD]), and increased blood pressure variability (BPV). Poor BRS may contribute to hypertension by impairing the control of blood pressure (BP), with increased BPV and HPD. Although children with OSA have elevated BP, there are scant data on BRS, BPV, or HPD in this group.Methods105 children ages 7–12 years referred for assessment of OSA and 36 nonsnoring controls were studied. Overnight polysomnography (PSG) was performed with continuous BP monitoring. Subjects were assigned to groups according to their obstructive apnea–hypopnea index (OAHI): primary snoring (PS) (OAHI ⩽1 event/h), mild OSA (OAHI > 1–⩽5 events/h) and moderate/severe (MS) OSA (OAHI > 5 events/h). BRS and HPD were calculated using cross spectral analysis and BPV using power spectral analysis.ResultsSubjects with OSA had significantly lower BRS (p < .05 for both) and a longer HPD (PS and MS OSA, p < .01; mild OSA, p < .05) response to spontaneous BP changes compared with controls. In all frequencies of BPV, the MS group had higher power compared with the control and PS groups (low frequency [LF], p < .05; high frequency [HF], p < .001).ConclusionsOur study demonstrates reduced BRS, longer HPD, and increased BPV in subjects with OSA compared to controls. This finding suggests that children with OSA have altered baroreflex function. Longitudinal studies are required to ascertain if this dampening of the normal baroreflex response can be reversed with treatment.     

Differential effects of sleep disordered breathing on polysomnographic characteristics in preschool and school aged children

ObjectiveChildhood sleep disordered breathing (SDB) peaks in the preschool years. We aimed to compare the effects of SDB on polysomnographic characteristics between preschool and school aged children.Participants and MethodsOne hundred and fifty-two preschool (3–5 y) and 105 school-aged (7–12 y) children, referred for assessment of SDB, plus controls (39, 3–5 y and 34, 7–12 y) with no history of snoring underwent overnight polysomnography. Subjects were grouped by their obstructive apnea hypopnea index (AHI) into those with primary snoring, mild obstructive sleep apnea (OSA), and moderate/severe OSA. The effects of SDB severity on sleep architecture and respiratory characteristics were compared between the age cohorts using quantile regression.ResultsThere was an average reduction in median sleep efficiency of 3.5% (p = 0.004) and an average increase in median WASO of 2% (p = 0.08) between the age cohorts across the severity groups, with sleep efficiency falling and WASO increasing with increasing SDB severity in the school-aged, but not the preschool, cohort. There was an average difference in median central AHI of 0.6 events/h (p < 0.001) between the age cohorts across the severity groups, with the 3–5 y old cohort but not the 7–12 y old cohort having more central apneas with increasing SDB severity.ConclusionsWe have demonstrated clinically important, age-related differences in sleep architecture in children with SDB. Preschool children with SDB maintain sleep efficiency and awaken fewer times throughout the night than do school aged children with a comparable severity of SDB, but experience more central apneas. This may have implications for the outcomes and treatment of SDB in children of different ages.     

Nocturnal polysomnographic characteristics of habitually snoring children initially referred to pediatric ENT or sleep clinics

ObjectivesTo determine clinical and polysomnographic characteristics of children initially referred by primary care physicians (PCP) to either otolaryngology or sleep clinics for a history of habitual snoring.MethodsRetrospective review of clinical characteristics and nocturnal polysomnograms (PSG) of snoring children referred initially to otolaryngologists by PCP (i.e., ENT) compared to a cross matched population of snoring children initially referred to a pediatric sleep center (i.e., SLEEP).ResultsSixty-eight ENT referred children were cross-matched to 68 SLEEP children. ENT referred children were found to have significantly larger tonsillar size compared to SLEEP children (tonsil size score 3.1 vs. 2.5, p value <0.01). Despite larger tonsillar size, there were no differences observed in the number of children with clinically significant obstructive sleep apnea syndrome (OSAS) with an obstructive apnea hypopnea index (OAHI) ? 5/h TST (40 ENT vs. 38 SLEEP children). Furthermore, SLEEP children with OSAS exhibited more severe sleep related breathing disturbances compared to ENT children (obstructive apnea index: 5.0 vs. 1.5 /h TST, p value <0.01; mean oxygen saturation nadir [76.3% vs. 87.0%, p < 0.01]). Finally, in 28 ENT referred children vs. 30 SLEEP the OAHI was <5/h TST.ConclusionsChildren referred by ENT are not more likely to be diagnosed with OSAS than snoring children directly referred to a pediatric sleep clinic by their pediatricians. The only difference in the referral decision between ENT and SLEEP seems to be tonsil size. Furthermore, PSG revealed a large percentage of children in whom surgical indication for AT is not obvious, thus suggesting that PSG is useful in determining the management of snoring children initially referred to ENT. Finally, SLEEP referred children diagnosed with OSAS exhibited increased indices among selected parameters indicative of sleep-disordered breathing.     

Uric acid excretion in North American and Southeast European children with obstructive sleep apnea

Background and objectivesResponses to nocturnal hypoxemia accompanying sleep-disordered breathing (SDB) may vary in different populations. Aims of this study were to (1) assess whether severity of SDB is related to uric acid excretion in North American and Southeast European children and (2) evaluate the interaction between nocturnal hypoxemia and country of children’s origin in uric acid excretion.MethodsConsecutive US and Greek children with snoring who were referred for polysomnography were recruited. Uric acid excretion expressed as uric acid-to-creatinine concentrations ratio in a morning urine specimen was the primary outcome measure.ResultsOne hundred and twenty-six US children (6.8 ± 0.7 years old) and 123 Greek children (6.4 ± 2.5 years old) were recruited. Forty-three US and 53 Greek participants had moderate-to-severe nocturnal hypoxemia (SpO₂ nadir <90%). Obstructive apnea-hypopnea index and SpO₂ nadir were related to uric acid excretion in Greek (but not US) children after adjustment by age, gender and body mass index z-score (p < 0.05). There was a significant interaction between severity of hypoxemia and country of children’s origin in uric acid excretion after adjustment by age, gender and body mass index z-score (p = 0.036). Greek children with moderate-to-severe hypoxemia had higher uric acid excretion (0.85 ± 0.35) than those with mild/no hypoxemia (0.69 ± 0.25) (p = 0.005). US children with moderate-to-severe hypoxemia (0.41 ± 0.20) did not differ in uric acid excretion from those with mild/no hypoxemia (0.42 ± 0.22) (p = 0.823).ConclusionsUric acid excretion differs in children with SDB and different ethnic backgrounds or environmental exposures.     

Increased risk of snoring and adenotonsillectomy in children referred for tympanostomy tube insertion

ObjectiveEustachian tube dysfunction and sleep-disordered breathing (SDB) share common pathophysiologic mechanisms. Our objective was to investigate whether children referred for isolated TTI (tympanostomy tube insertion) are at increased risk for snoring and upper airway procedures.MethodsTelephone interviews to parents of children who underwent isolated TTI and to age- and gender-matched controls were conducted.ResultsFour hundred fifty-seven children were included in the study; 352 had isolated TTI (study group) and 105 children were controls. Twenty-two percent of children in the study group were reported to snore compared with 7.6% in the controls (p = 0.001). Eighteen percent of children in the study group were reported to have undergone adenotonsillectomy compared with 4.8% in the controls (p = 0.0005). Future SDB, i.e., either snoring or adenotonsillectomy following TTI, was found in 34% of children in the study group compared with 11% in the controls (p = 0.0004). Children who underwent isolated TTI were at increased risk for future snoring (OR = 3.4, CI: 1.6–7.2) and future adenotonsillectomy (OR = 4.4, CI: 1.7–11.2).ConclusionsChildren who undergo isolated TTI are at increased risk for snoring and for adenotonsillectomy. We suggest that these children be followed for symptoms of SDB on a scheduled basis to allow for early diagnosis and intervention.     

Validation of the Sleep Disturbance Scale for Children and prevalence of parent-reported sleep disorder symptoms in Chinese children

ObjectiveTo translate and validate the Sleep Disturbance Scale for Children (SDSC), a promising questionnaire for use among children in epidemiological studies, in Chinese children.MethodsIn total, 3525 children aged 5–16 years were randomly selected from five primary schools in Shenyang. Internal consistency, reliability and factor analyses were undertaken to assess the construct validity of the SDSC.ResultsInternal consistency indicated adequate reliability (Cronbach’s α = 0.81). Factor analytic results indicated a six-factor solution (ie, six types of sleep disorder) based on parent-reported sleep disorder symptoms. The mean total score of the SDSC was 39.28 ± 7.83 and 156 (4.43%) children were identified as suffering from parent-reported sleep disorder. The prevalence for each sleep type disorder ranged from 3.46% to 6.30% with the highest for sleep hyperhidrosis (SHY) and the lowest for disorders of initiating and maintaining sleep. Significant differences were found between boys and girls in the prevalence of sleep breathing disorders (6.51% vs 3.72%), SHY (8.62% vs 4.00%) and parent-reported sleep disorders (5.19% vs 3.67%).ConclusionsThe SDSC is reliable and useful in screening for parent-reported sleep disorders in Chinese children. Compared with other countries, parent-reported sleep disorders among Chinese elementary school children were at a relatively low level of prevalence.     

Sleep disturbances in Malaysian patients with Parkinson's disease using polysomnography and PDSS

BackgroundSleep disturbances such as sleep fragmentation, sleep disordered breathing (SDB), periodic limb movements (PLM), excessive daytime somnolence (EDS) and insomnia are prevalent in Parkinson's disease (PD). However, studies in the Asian population are limited.MethodsThis was a cross-sectional study involving 46 Malaysians with PD using polysomnography (PSG) and standardized translated Parkinson's disease sleep scale (PDSS). Overnight PSG recordings, UPDRS and PDSS scores, and baseline demographic data were obtained.ResultsData from 44 patients were analysed. Thirty-six patients (81.8%) had PSG-quantified sleep disorders. Twenty-three (52.3%) had sleep fragmentation, 24 (54.6%) had SDB and 14 (32%) had PLM. EDS was present in 9.1%. Insomnia was reported by 31.8%. Patients with sleep fragmentation had significantly higher UPDRS scores and lower PDSS insomnia sub-scores. The UPDRS scores correlated negatively with the TST and sleep efficiency. All patients with EDS had SDB (p = 0.056). The PDSS insomnia sub-items correlated with sleep fragmentation on PSG.Conclusion: The prevalence of sleep disorders based on PSG and PDSS in our PD patients was high, the commonest being sleep fragmentation and SDB, while EDS was the least prevalent. Problem specific sub-items of the PDSS were more accurate in predicting the relevant PSG-related changes compared to the PDSS as a whole.     

Prevalence and factors associated with snoring in 3-year olds: Early links with behavioral adjustment

ObjectiveIdentify the prevalence of sleep disordered breathing (SDB) symptoms in a community sample of New Zealand 3-year olds. To examine sleep, demographic, health, environmental, familial, perinatal, and behavioral adjustment factors associated with habitual snoring.MethodsA cross sectional study, in which parents of 823 children aged 3 years 0 months to 3 years 12 months (M:F = 1:0.9) were recruited from the community. Participants completed questionnaires designed to assess information relevant to their children’s sleep, with a particular focus on snoring.ResultsParents reported snoring at least once a week in 36.9% of children, and habitual snoring (more than four nights per week) in 11.3% of children. Univariate analysis showed habitual snoring was more common amongst Māori (indigenous New Zealanders) (P = 0.04) and males (P = 0.05), and that habitual snorers came from more socio-economically deprived neighborhoods (P < 0.01). Several other SDB-related symptoms were significantly associated with habitual snoring: mouth breathing, sweating profusely, waking during the night, sleeping with neck extended, constant runny nose, and suffering from tonsillitis. Mouth breathing was the most strongly associated. Multivariate analyzes revealed a strong positive relationship between snoring and some health and familial factors, as well as parent reported child irritability (OR = 2.83; 95% CI 1.4–5.6) and hyperactivity (OR = 1.6; 95% CI 1.0–2.7).ConclusionsThe prevalence of habitual snoring amongst New Zealand pre-schoolers is similar to that reported elsewhere. Factors associated with habitual snoring include male gender, Māori ethnicity, and poorer deprivation neighborhood, as well as a variety of other environmental and health factors. The data provide evidence that habitual snoring associated with irritable and hyperactive behavior is evident in children as young as three.     

Sleep disorders in children with cerebral palsy: neurodevelopmental and behavioral correlates

ObjectivesWe aimed to estimate the frequency of sleep disorders in children with cerebral palsy (CP) using the Sleep Disturbance Scale for Children (SDSC) and to evaluate the relations between sleep disorders and motor, cognitive, and behavioral problems.MethodsOne hundred and sixty-five children with CP ages 6–16 years (mean age, 11 years) were assessed using the SDSC, the Gross Motor Function Classification System (GMFCS), the Wechsler Intelligence Scale for Children and the Child Behavior Check List (CBCL) to assess sleep, motor, cognitive, and behavioral problems, respectively.ResultsAn abnormal total sleep score was found in 19% of children with CP; more than 40% of children had an abnormal score on at least one SDSC factor. The SDSC total score was significantly associated (P < .01) with mental retardation, epilepsy, CBCL scores, and level 5 on the GMFCS.ConclusionsOur results confirm that sleep disorders are common in children with cerebral palsy. The relationship between motor and cognitive behavior and epilepsy should be further explored to better understand how these factors influence one another to identify effective treatments and to improve the well-being of the child.     

Risk factors associated with short sleep duration among Chinese school-aged children

ObjectivesTo examine risk factors regarding short sleep duration among Chinese school-aged children.MethodsA random sample of 20,778 children aged around 5–11 years participated in a cross-sectional survey, which was conducted in eight cities of China in 2005. A parent-administered questionnaire was used to collect information on children’s sleep duration and possible related factors from eight domains. Short sleep duration was defined as total sleep duration <9 h per day.ResultsIn all, 28.3% of the sampled children slept <9 h per day. The multivariate logistic regression identified, after adjusting for demographic and socioeconomic variables, factors associated with short sleep duration: more television viewing during weekdays (OR = 1.21, p = 0.004), more frequent computer/internet using (OR = 1.17, p = 0.006), earlier school starting time (OR = 1.10, p = 0.020), more time on homework during weekdays (OR = 1.66, p < 0.001) and weekends (OR = 1.14, p = 0.001), poor bedtime hygiene (e.g., having drinks with caffeine after 6:00PM [OR = 1.22, p < 0.001], doing exciting activities during bedtime [OR = 1.16, p < 0.001], and irregular bedtime [OR = 1.55, p < 0.001]), and shorter sleep duration of parents (mother: OR = 1.31, p < 0.001 for sleep duration <6 h and OR = 1.24, p = 0.006 for 6–8 h; father: OR = 1.52, p < 0.001 for <6 h and OR = 1.19, p < 0.001 for 6–8 h).ConclusionsFactors associated with sleep duration covered multidimensional domains among school-aged children. Compared to sleep environments and chronic health problems, school schedules, lifestyle patterns, and parents’ sleep habits had greater impact on children’s sleep duration, indicating the existing chronic sleep loss in school children could be, at least partly, intervened by reducing the use of visual technologies, by changing the school schedules, by improving the sleep hygiene routine, and by regulating parents’ sleep habits.     

The effect of childhood obstructive sleep apnea on ambulatory blood pressure is modulated by the distribution of respiratory events during rapid eye movement and nonrapid eye movement sleep

ObjectiveWe aimed to investigate if different childhood obstructive sleep apnea (OSA) subtypes, namely rapid eye movement (REM)-related, nonrapid eye movement (NREM)-related and stage-independent OSA would exert different effects on ambulatory blood pressure (ABP).MethodsData from our previous school-based cross-sectional study were reanalyzed. Subjects who had an obstructive apnea–hypopnea index (OAHI) between 1 and 10 events per hour and a total REM sleep duration of >30 min were included in our analysis. REM-related and NREM-related OSA were defined as a ratio of OAHI in REM sleep (OAHI_REM) to OAHI in NREM sleep (OAHI_NREM) of >2 and <0.5, respectively. The others were classified as stage-independent OSA.ResultsA total of 162 subjects were included in the analysis. In the mild OSA (OAHI, 1–5 events/h) subgroup, no significant differences in any ABP parameters were found between OSA subtypes. On the other hand, in subjects with moderate OSA (OAHI, 5–10 events/h), the REM-related OSA subtype had a significantly lower daytime systolic blood pressure (SBP) z score (−0.13 ± 0.90 cf 1.15 ± 0.67; P = .012) and nighttime SBP z score (0.29 ± 1.06 cf 1.48 ± 0.88, P = .039) than the stage-independent OSA subtype. Linear regression analyses revealed that OAHI_NREM but not OAHI_REM was significantly associated with both daytime (P = .008) and nighttime SBP (P = .042) after controlling for age, gender, and body size.ConclusionChildren with obstructive events mainly in REM sleep may have less cardiovascular complications than those with stage-independent OSA.     

Subjective sleep disturbances in children with partial epilepsy and their effects on quality of life

PurposeThe purposes of this study were to explore the prevalence of sleep disturbances in a large cohort of school-aged children with partial epilepsy, to compare the findings with those in children without epilepsy of the same age and gender, and to evaluate the relationship between sleep disturbances and health-related quality of life (HRQoL).MethodsOne hundred thirty children with partial epilepsy aged 4 to 10 years, who were treated in the outpatient setting of a Dutch epilepsy clinic, and 161 age- and sex-matched controls participated in this study. In addition to providing information about their child's demography and health, parents of both groups of children completed three questionnaires to measure their child's sleep [Sleep Disturbance Scale for Children (SDSC), Medical Outcomes Study-Sleep Scale (MOSS-S), and Groningen Sleep Quality Scale (GSQS)] and one questionnaire to measure quality of life (Kidscreen-27). Parents of children with epilepsy also completed the Hague Scales to measure the severity of epilepsy. The prevalence of sleep disturbances and scores on HRQoL in children with and without epilepsy were compared. Additionally, the HRQoL scores were compared between children with and without sleep disturbances in children both with and without epilepsy.ResultsThe answers for all three questionnaires suggested worse sleep in children with epilepsy than in children of the same age and gender without epilepsy. Pathological scores (T-value > 70) for total SDSC were seen twelve times more frequently in children with epilepsy (36.92% vs. 3.01%, p < 0.001). Children with epilepsy also scored significantly lower for all dimensions of HRQoL. Between subgroups of children with and without disturbed sleep, insignificant differences in quality of life were found, with the lowest scores in children with sleep disturbances in both groups.ConclusionThis study confirms the high prevalence of disturbed sleep, as well as its effect on quality of life, in a large group of children with partial epilepsy. The abnormalities are both more prevalent and more severe than in children without epilepsy.     

Sleep disorders and daytime sleepiness in children with attention-deficit/hyperactivity disorder: A two-night polysomnographic study with a multiple sleep latency test

ObjectiveTo evaluate sleep macrostructure, sleep disorders incidence and daytime sleepiness in attention-deficit/hyperactivity disorder (ADHD) affected children compared with controls.MethodsThirty-one patients (26 boys, 5 girls, mean age 9.3 ± 1.7, age range 6–12 years) with ADHD diagnosed according to DSM-IV criteria, without comorbid psychiatric or other disorders, as never before pharmacologically treated for ADHD. The controls were 26 age- and sex-matched children (22 boys, 4 girls, age range 6–12 years, mean age 9.2 ± 1.5). Nocturnal polysomnography (PSG) was performed for two nights followed by the multiple sleep latency test (MSLT).ResultsNo differences between the two groups comparing both nights were found in the basic sleep macrostructure parameters or in the time (duration) of sleep onset. A first-night effect on sleep variables was apparent in the ADHD group. Occurrence of sleep disorders (sleep-disordered breathing [SDB], periodic limb movements in sleep [PLMS], parasomnias) did not show any significant differences between the investigated groups. A statistically significant difference (p = 0.015) was found in the trend of the periodic limb movement index (PLMI) between two nights (a decrease of PLMI in the ADHD group and an increase of PLMI in the control group during the second night). While the mean sleep latency in the MSLT was comparable in both groups, children with ADHD showed significant (sleep latency) inter-test differences (between tests 1 and 2, 1 and 4, 1 and 5, p < 0.01).ConclusionAfter the inclusion of adaptation night and exclusion of psychiatric comorbidities, PSG showed no changes in basic sleep parameters or sleep timing, or in the frequency of sleep disorders (SDB, PLMS) in children with ADHD compared with controls, thus not supporting the hypothesis that specific changes in the sleep macrostructure and sleep disturbances are connected with ADHD. A first-night effect on sleep variables was apparent only in the ADHD group. Though we found no proof of increased daytime sleepiness in children with ADHD against the controls, we did find significant vigilance variability during MSLT in the ADHD group, possibly a sign of dysregulated arousal.     

Sleep patterns and sleep disturbances among Chinese school-aged children: Prevalence and associated factors

ObjectiveThe study aimed to (1) characterize sleep patterns and sleep disturbances among Chinese school-aged children, (2) determine the prevalence of their short sleep duration and sleep disturbances based on clinical cutoffs, and (3) examine possible factors (socio-demographic factors and emotional/behavioral problems) that are associated with sleep disturbances.MethodsA large representative sample of 912 children aged 6–14 years was recruited from Shenzhen, China. Their parents completed the Children’s Sleep Habits Questionnaire (CSHQ) and the Strengths and Difficulties Questionnaire (SDQ).ResultsThe mean bedtime was 9:45 pm (SD = 1 h 11 min), mean wake-up time was 7:03 am (SD = 31 min), mean sleep duration was 9 h 14 min (SD = 46 min), and 23.8% of the children had sleep duration <9 h. Overall, 69.3% of the children suffered from global sleep disturbances (CSHQ total score >41). Bedtime resistance (22.9%), sleep anxiety (22.1%), sleep duration (21%) and daytime sleepiness (20%) were the most prevalent sleep disturbances; followed by sleep disordered breathing (12.1%), parasomnias (9.4%), sleep onset delay (6.9%), and night waking (5.2%). The prevalence of specific sleep disturbances ranged from 3.2% (falling asleep while watching television) to 81.9% (awakening by others in the morning). Correlations between most domains of sleep disturbances and emotional/behavioral problems were statistically significant (p < 0.05 or p < 0.01). Hierarchical multiple regression analysis revealed that gender (β = 0.10, p < 0.01), school grade (β = −0.09, p < 0.05), co-sleeping (β = 0.25, p < 0.01), emotional symptoms (β = 0.24, p < 0.01), conduct problems (β = 0.09, p < 0.05), and hyperactivity (β = 0.17, p < 0.01) accounted for significant variance in CSHQ total score.ConclusionsShort sleep duration and sleep disturbances are prevalent among Chinese school-aged children. Sleep disturbances are associated with gender, school grade, co-sleeping, emotional symptoms, conduct problems, and hyperactivity.     

Sleep-disordered breathing and cardiac autonomic modulation in children

ObjectivesTo investigate the adverse cardiac autonomic effects of sleep-disordered breathing (SDB) in a large population-based sample and a clinical sample of children.MethodsSubjects included a population-based sample of 700 and a clinically diagnosed sample of 43 SDB children. SDB was defined based on an apnea hypopnea index (AHI) ? 1 during one night of polysomnography. Cardiac autonomic modulation was measured by heart rate variability (HRV) analysis of the beat-to-beat RR interval data collected during polysomnography.ResultsThe mean (SD) age was 112 (21) months, with 49% male and 25% non-white. About 73.0% had AHI < 1 (no SDB), 25.8% had 1–5 AHI (mild SDB), and 1.2% had ?5 AHI (moderate SDB). Among individuals with moderate SDB in the population-based sample and the clinically diagnosed SDB patients, the mean (SE) of HRV-high frequency power (HF) was significantly lower compared to children without SDB [6.00 (0.32) and 6.24 (0.14), respectively, vs. 6.68 (0.04) ms², p < 0.05 and p < 0.01, respectively], whereas the low frequency power to high frequency power ratio (LF/HF) was significantly higher [1.62 (0.20) and 1.74 (0.09), respectively, vs. 0.99 (0.02), both p < 0.01)].ConclusionsSDB in healthy young children and in clinical patients is significantly associated with impaired cardiac autonomic modulation, i.e., sympathetic overflow and weaker parasympathetic modulation, which may contribute to increased risk of acute cardiac events in persons with SDB, even before reaching the “high risk age.”