Sleep problems in Australian children with Down syndrome: the need for greater awareness

BackgroundChildren with Down Syndrome (DS) have a high prevalence of obstructive sleep apnoea (OSA). Non-respiratory sleep disorders also occur commonly but are less well recognised. This cross-sectional study evaluates the prevalence of sleep difficulties in a community sample of Australian children with DS (DS_comm), using the Children's Sleep Habits Questionnaire (CSHQ), and compares them to children referred to the sleep clinic (DS_ref). To our knowledge this is the first study to have reported prevalence of sleep problems in Australian children with DS and to compare a community and referred group of children with DS directly.MethodsThe CSHQ was completed by parents of children with DS recruited from the community (DS_comm) via survey distributed by Down syndrome Queensland and Australia. A second group was recruited through the tertiary sleep clinic at our institution (DS_ref) and completed the same questionnaire on enrolment. Data from these groups was compared.ResultsThere were 76 participants in the DS_comm group (57% male; median age 9.7yrs) and 42 participants in the DS_ref group (50% male; median age 6.97yrs). The overall prevalence of sleep disturbances was 90.9% in the DS_comm group, and 85.7% in the DS_ref group (p = 0.54). There was a statistically significant difference in the mean total CSHQ score, with the DS_comm having the higher score (p = 0.023).ConclusionsThis study reports a high prevalence of sleep problems in both a community and referred group of Australian children with DS and suggests that there are many children with DS with sleep problems, particularly non-respiratory difficulties, who are potentially not receiving adequate treatment.     

Evaluating sleep quality using the CSHQ-Autism

BackgroundSleep problems are common in autistic children and adversely impact daytime functioning. The Children's Sleep Habits Questionnaire (CSHQ) [39] was developed from a community-based sample of children and has validated a cut-off score of 41. Katz et al. [50] developed an abbreviated 23-item four-factor version of the CSHQ, which may be useful when assessing sleep in autistic children. However, a cut-off value has not yet been developed. Objective: Our objective was to develop and validate a cut-off for the CSHQ-autism total score in order to identify sleep problems among autistic children. We hypothesized that the derived cut-off value for the CSHQ-autism would perform better than the original CSHQ cut at 41 on validation in a sample of autistic children.MethodsAge-specific cut-off values were developed and validated using receiver operating characteristic analysis.ResultsThe derived cut-off values for the CSHQ-autism total score were 34, 35, 33, and 35 for the 2–3, 4–10, 11–17, and 2–17 years age groups, respectively. On validation, all cut-off values performed with moderate to high sensitivity (76.6–82.4%) and moderate specificity (69.1–75.5%), while the original CSHQ cut at 41 had high sensitivity (89.9–93.0%) but low specificity (42.6–57.7%). Using McNemar's tests, the CSHQ-autism had significantly higher specificity but lower sensitivity than the original CSHQ cut at 41 in all age groups.ConclusionsThe CSHQ-autism cut-off values performed better overall than the original CSHQ cut at 41 in a sample of autistic children. The CSHQ-autism cut-off can help identify sleep problems among autistic children.     

Brain tumours result in sleep disorders in children and adolescents

Background and objectivesSleep disturbances are frequently reported in children with brain tumours. The objective of our cross-sectional study was to systematically examine sleep in these children. We hypothesised that children with tumours involving the sleep-wake-regulatory areas have an altered sleep-wake-regulation.MethodsSixty-one patients aged 0–18 years and with a diagnosis of a primary brain or cervical medullary tumour were included. They were categorised based upon tumour location into two groups – those affecting the sleep-wake regulatory regions, i.e. brain stem, basal forebrain, hypothalamus, thalamus, and posterior fossa compressing the brain stem and those that did not. Sleep history, questionnaire surveys, polysomnography, and multiple sleep latency test were used, as indicated clinically. Surveys included Pediatric Daytime Sleepiness Scale, Children's Sleep Habits Questionnaire, Strengths and Difficulties Questionnaire, and Pediatric Quality of Life Inventory, Multidimensional Fatigue Scale and Generic Core Scale.ResultsPatients with tumours involving the sleep-wake regulatory areas were sleepier/more fatigued (p = 0.03). Sleep apnoea was observed in 86% of all the patients and comorbid narcolepsy in 8%, without group differences (p ≥ 0.12). Patients with tumours involving the sleep-wake-regulatory areas had more emotional problems (p = 0.04), were more affected by mental health problems (p < 0.001), and had poorer quality of life (p ≤ 0.03).ConclusionsMany children with brain tumours suffer from disturbed sleep, poor mental health, and low quality of life. We recommend that systematic sleep evaluation is included in their routine care along with psychological and social support.     

Social jetlag is associated with obesity-related outcomes in 9–11-year-old children,independent of other sleep characteristics

IntroductionSocial jetlag has been reported to predict obesity-related indices, independent of sleep duration, with associations in female adolescents but not males. However, such sex-specific relationships have not been investigated in pre-adolescents.ObjectivesTo examine: (i) the relationships between sleep characteristics, including social jetlag, and obesity-related outcomes during childhood, and (ii) whether these relationships are moderated by sex.MethodsThis cross-sectional study included 381 children aged 9–11 years (49.6% female). Average sleep duration, social jetlag, and physical activity were assessed via wrist-worn accelerometry. Sleep disturbances were quantified from the Children's Sleep Habits Questionnaire. Obesity-related outcomes included age-specific body mass index Z-scores (zBMI) and waist-to-height ratio. Additionally % fat, total fat mass, and fat mass index were assessed via bioelectrical impedance analysis. Linear mixed models that nested children within schools were used to identify relationships among sleep characteristics and obesity-related outcomes.ResultsPositive associations between social jetlag with zBMI, % fat, and fat mass index were seen in univariable and unadjusted multivariable analyses. Following adjustments for known confounders, social jetlag remained significantly associated with zBMI (β = 0.12, p = 0.013). Simple slopes suggested a positive association in girls (β = 0.19, p = 0.006) but not in boys (β = 0.03, p = 0.703).ConclusionsObesity prevention efforts, particularly in girls, may benefit from targeted approaches to improving the consistency of sleep timing in youth.     

The evaluation of sleep disturbances for Chinese frontline medical workers under the outbreak of COVID-19

ObjectiveTo evaluate sleep disturbances of Chinese frontline medical workers (FMW) under the outbreak of coronavirus disease 2019 (COVID-19), and make a comparison with non-FMW.MethodsThe medical workers from multiple hospitals in Hubei Province, China, volunteered to participate in this cross-sectional study. An online questionnaire, including Pittsburgh Sleep Quality Index (PSQI), Athens Insomnia Scale (AIS) and Visual Analogue Scale (VAS), was used to evaluate sleep disturbances and mental status. Sleep disturbances were defined as PSQI>6 points or/and AIS>6 points. We compared the scores of PSQI, AIS, anxiety and depression VAS, as well as prevalence of sleep disturbances between FMW and non-FMW.ResultsA total of 1306 subjects (801 FMW and 505 non-FMW) were enrolled. Compared to non-FMW, FMW had significantly higher scores of PSQI (9.3 ± 3.8 vs 7.5 ± 3.7; P < 0.001; Cohen's d = 0.47), AIS (6.9 ± 4.3 vs 5.3 ± 3.8; P < 0.001; Cohen's d = 0.38), anxiety (4.9 ± 2.7 vs 4.3 ± 2.6; P < 0.001; Cohen's d = 0.22) and depression (4.1 ± 2.5 vs 3.6 ± 2.4; P = 0.001; Cohen's d = 0.21), as well as higher prevalence of sleep disturbances according to PSQI > 6 points (78.4% vs 61.0%; relative risk [RR] = 1.29; P < 0.001) and AIS > 6 points (51.7% vs 35.6%; RR = 1.45; P < 0.001).ConclusionFMW have higher prevalence of sleep disturbances and worse sleep quality than non-FMW. Further interventions should be administrated for FMW, aiming to maintain their healthy condition and guarantee their professional performance in the battle against COVID-19.     

Screen exposure exacerbates ADHD symptoms indirectly through increased sleep disturbance

ObjectivesThe aim of this study was twofold. First, to confirm the deleterious aspect of evening screen exposure in school-aged children, in particular the effect of screens in the bedroom. Second, to explore the three-way association between degree of screen exposure, sleep disturbance, and ADHD symptoms. Solid evidence exists on the link between sleep disturbance and ADHD symptoms, and screen exposure and sleep disturbance. However, no studies have formally assessed the impact of screen exposure on ADHD symptoms in children, as a function of sleep disturbance.MethodsParents of 374 French children (201 girls, 173 boys, mean age of 10.8 ± 2.8 years old) completed the Sleep Disturbance Scale for Children (SDSC), the Attention-Deficit/Hyperactivity Disorder (ADHD) Rating Scale, and a questionnaire about their children's screen habits (total hours in the morning, afternoon, and evening per day). Correlational analyses between evening screen exposure, sleep quality and behavioral problems were conducted. Then, formal mediation analyses were run in order to quantify the relationship between variables.ResultsSchool-aged children with screens in their bedrooms demonstrated more sleep and behavioral problems. Evening TV exposure was associated with higher SDSC and ADHD scores. Furthermore, the Structural Equation Modelling approach confirmed that evening screen exposure is directly associated with more disrupted sleep, which in turn is directly associated with behavioral problems.ConclusionsThese findings encourage families to avoid putting screens in their children's bedrooms, and limit evening screen exposure. They furthermore demonstrate the importance of taking into account screen exposure time (morning, afternoon, evening) and location (bedroom or elsewhere) in future studies.     

The prevalence of sleep problems among children in mainland China: a meta-analysis and systemic-analysis

BackgroundWe conducted a meta-analysis and systematic review to identify a reliable estimate of sleep problems prevalence among children in mainland China and to describe its epidemiological characteristics.MethodsRelevant studies were searched thoroughly via electronic databases included China National Knowledge Infrastructure, Wanfang, Weipu, PubMed, Embase and Medline databases from inception until December 2020. Prevalence estimates were calculated by random-effects models. The sources of heterogeneity were explored using subgroup analyses and Meta-regression analysis, and publication bias was estimated by funnel plots and Egger's Test.ResultsOverall, 66 studies were included in this meta-analysis, which revealed that the pooled prevalence of sleep problems was 37.6% (95%CI: 34.3–40.9%) with high heterogeneity (I² = 99.6%,P < 0.001). The incidence of snoring was 7.7%, choking or gasping was 0.9%, apnea was 1.5%, restless sleep was 11.3%, mouth breathing was 4.7%, hyperhidrosis was 17.2%, leg movements was 2.7%, bruxism was 9.6%, sleep talking was 0.7%, sleep-walking was 0.8%, nightmare was 5.1%, enuresis was 3.4%, night awakening was 6.7% and trouble falling asleep was 11.1%. The prevalence rate of sleep problems among males was higher than females (OR:1.01,95%CI:1.05–1.13). In all age groups, the prevalence rates of sleep problems increased with age, including infancy or early childhood group (33.3%), pre-school group (38.9%), school-age group (43.7%). The prevalence rate in South China (30.4%, 95%CI: 23.9–36.8%) was the lowest, and the highest prevalence rate was in West China (47.4%,95%CI:35.9–58.9%), which than any other region in China. The point estimate for sleep disorders prevalence obtained using the CSHQ criterion was higher than other criteria. Meta-regression indicated that age group could influence prevalence estimation (P = 0.011).ConclusionsOver the past two decades, the prevalence rate of sleep problems among children in mainland China has increased, significantly affecting two-fifth of the school-age children. The incidence of hyperhidrosis, restless sleep and trouble falling asleep were significantly higher than other sleep prombles. The prevalence rate of sleep problems in west China was significantly higher than in any other area. There is still a lack of guidelines on children's sleep problems in mainland China, so future research should pay special attention to the sleep problems of school-age children and children in economically backward areas.     

The effectiveness of diaphragmatic breathing relaxation training for improving sleep quality among nursing staff during the COVID-19 outbreak: a before and after study

ObjectivesRecent studies have demonstrated that first-line nurses involved in the coronavirus disease-2019 (COVID-19) crisis may experience sleep disturbances. As breathing relaxation techniques can improve sleep quality, anxiety, and depression, the current study aimed to evaluate the effectiveness of diaphragmatic breathing relaxation training (DBRT) for improving sleep quality among nurses in Wuhan, China during the COVID-19 outbreak.MethodsThis study used a quasi-experimental (before and after) intervention strategy, with 151 first-line nurses from four wards in Leishenshan hospital. The Pittsburgh Sleep Quality Index (PSQI), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS) to evaluate the effectiveness of DBRT before and after the intervention. Data were examined using the Shapiro–Wilk test, Levene's test, and paired t-test.ResultsA total of 140 nurses completed the DBRT sessions. First-line nurses achieved significant reductions in global sleep quality (p < 0.01), subjective sleep quality (p < 0.001), sleep latency (p < 0.01), sleep duration (p < 0.001), sleep disturbances (p < 0.001), habitual sleep efficiency (p = 0.015), daytime dysfunction (p = 0.001), and anxiety (p = 0.001). There were no significant reductions in the use of sleeping medication (p = 0.134) and depression (p = 0.359).ConclusionDBRT is a useful non-pharmacological treatment for improving sleep quality and reducing anxiety among first-line nurses involved in the COVID-19 outbreak.The study protocol was clinically registered by the Chinese Clinical Trial Registry. Clinical Trial Registration number: ChiCTR2000032743.     

Female and male sleep duration in association with the probability of conception in two representative populations of reproductive age in US and China

ObjectiveSleep duration has been found to affect some reproductive phenotypes but fecundability has been rarely researched. We aim to evaluate the association between female/male sleep duration and the probability of conception in two representative populations.MethodsThe present study uses two datasets, namely, a cross-sectional dataset of 9137 reproductive-age females in the US (National Health Interview Survey, NHIS) and a longitudinal dataset of 2687 reproductive-age females and their male mates in China (China Health and Nutrition Survey, CHNS). Logistic regression or mixed model was used to analyze the association between sleep duration and the probability of conception in the females of both populations and in CHNS males with adjustments for demographic, socioeconomic, behavioral, sleep health and reproductive factors.ResultsAn inverse association was observed between male sleep duration (≥8 h/day) and their mates' conception probability in the CHNS population (P = 0.012). Sleep of 9 h/day and ≥10 h/day in men was associated with 0.65 (0.41–1.02) fold and 0.53 (0.31–0.90) fold of conception probability when compared to 8 h/day sleep. On the other hand, a U-shaped association between female sleep duration and conception probability was observed in both populations. Each hour/day departure (longer or shorter) from 7 h/day sleep was associated with 1.26 (1.12–1.42, P < 0.001) and 1.21 (1.03–1.41, P = 0.019) fold conception probability in the NHIS and CHNS populations, respectively. An adjustment for potential confounders, including spouse characteristics did not substantially attenuate these associations.ConclusionsFemale and male sleep duration may be independent predictors of conception, suggesting there is an intervention target for reproductive health.     

An investigation into an evening intake of a saffron extract (affron®) on sleep quality,cortisol, and melatonin concentrations in adults with poor sleep: a randomised,double-blind,placebo-controlled,multi-dose study

Objective/backgroundTo validate and extend on previous positive findings of the sleep-enhancing effects of saffron supplementation in adults with unsatisfactory sleep.Patients/methodsIn this 28-day, 3-arm, parallel-group, double-blind, randomised controlled trial, 120 adults with unsatisfactory sleep received either a placebo, 14 mg, or 28 mg of a standardised saffron extract (affron®), 1 h before bed. Outcome measures included the Pittsburgh Sleep Diary (with sleep quality ratings as the primary outcome measure), Insomnia Symptom Questionnaire (ISQ), Profile of Mood States, Restorative Sleep Questionnaire, the Functional Outcomes of Sleep Questionnaire, and evening salivary melatonin and cortisol concentrations.ResultsCompared to the placebo, saffron supplementation was associated with greater improvements in sleep quality ratings (primary outcome measure), mood ratings after awakening, the ISQ total score, and ISQ-insomnia classifications. However, there were no significant differences between the saffron and placebo groups in other questionnaire and sleep diary outcome measures. Sleep improvements were similar for the two administered saffron doses. Compared to the placebo, saffron supplementation was associated with increases in evening melatonin concentrations but did not affect evening cortisol. Saffron supplementation was well-tolerated with no reported significant adverse effects.ConclusionsThese results provide further validation of the sleep-enhancing effects of 28-days of saffron supplementation in adults with unsatisfactory sleep. Further research is required to examine the efficacy and safety of saffron supplementation using objective sleep measures, over a longer duration, in people presenting with a diagnosed insomnia disorder and other psychogenic and demographic characteristics, and into its potential sleep-enhancing mechanisms of action.     

A meta-analysis of the relationship between subjective sleep and depressive symptoms in adolescence

BackgroundAdolescence is a risk period for the development of mental illness, as well as a time for pronounced change in sleep behaviour. While prior studies, including several meta-analyses show a relationship between sleep and depressive symptoms, there were many inconsistences found in the literature.ObjectiveTo investigate the relationship between subjective sleep and depressive symptoms.MethodsFollowing PRISMA guidelines, we conducted a literature search that yielded forty-nine recent studies (2014–2020) with adolescent samples aged 9 to 25-year-olds, and more than double the sample size of previous meta-analyses (N = 318,256).ResultsIn a series of meta-analyses, we show that while several common categories of subjective sleep are associated with depressive symptoms in adolescents, the strength of this relationship varies. Measures of sleep perception: poor sleep quality (r = 0.41), insomnia (r = 0.37), sleep disturbances (r = 0.36), wake after sleep onset (r = 0.31), and daytime sleepiness (r = 0.30) correlated more strongly with depressive symptoms, than measures of sleep behaviour: sleep latency (r = 0.22), and sleep duration (r = −0.19).ConclusionsThese findings suggest that in studies of depressive symptoms it may be important to assess an adolescent's perception about their sleep, in addition to their sleep/wake behaviours.     

The relationship between gross motor function impairment in cerebral palsy and sleeping issues of children and caregivers

AimTo investigate, among children and adolescents with cerebral palsy (CP), the relationship between impairment of the gross motor function and: (i) child sleep disorders; (ii) the need for nocturnal support; and (iii) the quality of sleep of their caregivers.MethodsFor children, we considered their scores on the gross motor function measure (GMFM-88) and on the sleep disturbance scale for children (SDSC), besides analyzing qualitative features about their sleep. For caregivers, we considered their scores in the Pittsburgh sleep quality index (PSQI).ResultsOur sample was comprised of 87 participants with mean age of 11.4 years old (±3.4). We observed correlations between GMFM-88 and disorders of initiating and maintaining sleep (DIMS) (r = −0.22; p = 0.039), sleep–wake transition disorders (SWTD) (r = 0.26; p = 0.017) and disorders of arousal (DA) (r = 0.23; p = 0.033). Children receiving nocturnal support presented lower scores in the GMFM-88 (p = 0.001) and higher scores in the SDSC (p = 0.029). For the caregivers, we found no correlation between GMFM-88 and PSQI. Nonetheless, their PSQI scores correlated with the SDSC scores (r = 0.24; p = 0.027).ConclusionImpairment of the gross motor function correlated with DIMS and the need for nocturnal support but might not have an impact on the caregivers’ sleep, which in turn correlated with child sleep disorders.     

Experimental sleep restriction increases somatic complaints in healthy adolescents

Short duration sleep and somatic complaints (bodily complaints like aches/pains or GI distress) are common in adolescence and may be linked, yet no published studies have tested causation. In this study, healthy adolescents (n = 30; 14–18yrs) completed a three-week, within-subject cross-over experiment. Following a sleep stabilization week, adolescents were randomized (in counterbalanced order) to five nights of 6.5hrs in bed (Insufficient Sleep) or 9.5hrs in bed (Sufficient Sleep), each preceded by a two-night “washout.” Somatic complaints were assessed via the Children's Somatic Symptoms Inventory (CSSI-24) and the Pain and Symptom Assessment Tool (PSAT) concluding each condition. Adherence to experimental condition was confirmed via actigraphy. Adolescents slept two fewer hours and reported significantly greater frequency and severity of somatic complaints during the Insufficient Sleep (vs. Sufficient Sleep) condition. Restricting sleep opportunity to a level common in adolescence causally increased somatic complaints in otherwise healthy adolescents. Findings support clinical and preventative efforts to address pervasively inadequate sleep in adolescence.     

Social jetlag is associated with cardiorespiratory fitness in male but not female adolescents

IntroductionCardiorespiratory fitness (CRF) is a vital sign that can improve risk classification for adverse health outcomes. While lifestyle-related factors are associated with CRF, few have examined the influence of sleep characteristics, especially in youths. Social jetlag, a mismatch between one's biological clock and sleep schedule, is prevalent in adolescents and associated with increased adiposity, though its relationship with CRF is unclear.ObjectiveTo quantify the relationship between social jetlag and CRF, independent of other sleep characteristics.MethodsThis cross-sectional sample includes 276 New Zealand adolescents (14–18 years, 52.5% female). CRF (VO_2max) was estimated from a 20-m multi-stage shuttle run. Average sleep duration, sleep disturbances, social jetlag, physical activity, and the number of bedroom screens were estimated from validated self-report surveys. Social jetlag is the difference in hours between the midpoint of sleep during weekdays (school) and weekend days (free). Combined and sex-stratified linear regression assessed the association between sleep outcomes and CRF, controlling for relevant covariates.ResultsMales slept 17.6 min less, had less sleep disturbances, and a 25.1-min greater social jetlag than their female peers (all p < 0.05). A 1-h increase in social jetlag was associated with a 0.72 ml/kg/min decrease in VO_2max (95% CI: −1.31, −0.14), independent of other sleep variables, which were not associated with CRF. Sex-specific models indicated an association in males (B −0.93, 95% CI: −1.76, −0.09), but not females (B −0.32, 95% CI: −1.18, 0.55).ConclusionsSocial jetlag is negatively associated with CRF in adolescent males and may be a simple, measurable target for public health interventions.     

Patterns and correlates of sleep duration in the Southern cohort community study

ObjectiveTo investigate whether race (African American (AA) and white) is associated with sleep duration among adults from low socioeconomic (SES) strata and whether SES status, lifestyle behaviors, or health conditions are associated with sleep duration within race-sex groups.MethodsThis cross-sectional study includes 78,549 participants from the Southern Community Cohort Study (SCCS). Averaged daily sleep duration was assessed by weighted averages of self-reported sleep duration on weekdays and weekends. Adjusted odds ratios (ORs) of very short (<5 h/day), short (5–6 h/day), and long sleep (≥9 h/day) associated with pre-selected risk factors in each race-sex group were determined by multinomial logistic models.ResultsThe prevalence of very short and short sleep was similar among AAs (6.2% and 29.1%) and whites (6.5% and 29.1%). Long sleep was considerably more prevalent among AAs (19.3%) than whites (13.0%). Very short sleep was associated with lower education and family income, with stronger associations among whites. Higher physical activity levels significantly decreased odds for both very short (OR = 0.80) and long sleep (OR = 0.78). Smoking, alcohol use, and dietary intake were not associated with sleep duration. Regardless of race or sex, very short, short, and long sleep were significantly associated with self-reported health conditions, especially depression (ORs were 2.06, 1.33, and 1.38, respectively).ConclusionsSleep duration patterns differed between AAs and whites from the underrepresented SCCS population with low SES. Sleep duration was associated with several socioeconomic, health behaviors, and health conditions depending on race and sex.     

Sleep quality in acromegaly and changes after transsphenoidal surgery: a prospective longitudinal study

ObjectiveTo elucidate the sleep quality characteristics and factors related to either good or poor sleep quality in acromegaly patients before surgery and to explore sleep quality changes after transsphenoidal surgery and the factors related to these changes.MethodsWe prospectively enrolled 39 acromegaly patients and 78 patients with nonfunctioning pituitary adenomas. Scales for anxiety, depression, disease stigma and nasal condition were evaluated. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was administered before surgery as well as one month and three months after surgery.ResultsA higher percentage of acromegaly patients had poor sleep quality compared to controls (35.9% vs. 5.1%, p < 0.001). In addition, acromegaly patients experienced worse subjective sleep quality, extended sleep latency, increased sleep disturbance and decreased daytime functioning. Higher scores for anxiety, disease stigma and sinonasal outcomes were correlated with worse sleep quality in acromegaly patients. At one month after transsphenoidal surgery, we found worse subjective sleep quality, extended sleep latency, shortened sleep duration, impaired sleep efficiency and increased sleep disturbance in acromegaly patients. At three months postoperatively, most impaired PSQI domains in acromegaly patients recovered to preoperative levels. The use of soluble gauze was related to decreased sleep quality at one month after surgery and severe anxiety and depression were related to improved sleep quality at three months after surgery.ConclusionsSleep quality was reduced in acromegaly patients. Moreover, sleep quality initially worsened after surgery but later recovered. Emotional problems and the use of soluble gauze were related factors.Clinical trial registrationNone.     

School closure during the coronavirus disease 2019 (COVID-19) pandemic – Impact on children's sleep

ObjectiveTo evaluate the sleep habits of school-going children before and during school closure in the national lockdown period (called ‘Circuit Breaker’ or CB in Singapore) due to the COVID-19 pandemic.MethodsCross-sectional, anonymous, online, population-based survey questionnaire was administered to parents aged 21 years and above with children aged between 3 and 16 years attending pre-school, primary or secondary school (equivalent to kindergarten, middle and-high school) and residing in Singapore. Sleep duration in relation to various daily activities including academic activities, physical exercise, and screen time was evaluated pre-CB and during CB.ResultsData from 593 participants were analyzed. Pre-CB, the overall mean (SD) sleep duration of the study population was 9.01 (1.18) hours on weekdays and 9.99 (0.94) hours on weekends. During CB, mean (SD) sleep duration overall was 9.63 (1.18) hours. Although children generally went to bed later (mean 0.65 h later), they woke up even later during CB (mean 1.27 h later), resulting in longer sleep duration (mean increase of 0.35 h). This was most evident in secondary school children (mean increase of 0.70 h). Children attending private schools (which had later start times) had increased sleep duration (mean 10.01 (SD 0.89) hours pre-CB and 10.05 (SD 0.93) hours during CB) compared to public schools (mean 9.05 (SD 0.91) pre-CB and 9.49 (SD 1.22) hours during CB).ConclusionsSchool closure from the COVID-19 pandemic resulted in longer sleep duration in school-going children. Early school/academic activity start times had a significant impact on limiting children's sleep duration.     

EEG and behavioural correlates of mild sleep deprivation and vigilance

ObjectiveThe current study investigated the behavioral, cognitive, and electrophysiological impact of mild (only a few hours) and acute (one night) sleep loss via simultaneously recorded behavioural and physiological measures of vigilance.MethodsParticipants (N = 23) came into the lab for two testing days where their brain activity and vigilance were recorded and assessed. The night before the testing session, participants either slept from 12am to 9am (Normally Rested), or from 1am to 6am (Sleep Restriction).ResultsVigilance was reduced and sleepiness was increased in the Sleep Restricted vs. Normally Rested condition, and this was exacerbated over the course of performing the vigilance task. As well, sleep restriction resulted in more intense alpha bursts. Lastly, EEG spectral power differed in Sleep Restricted vs. Normally Rested conditions as sleep onset progressed, particularly for frequencies reflecting arousal (e.g., delta, alpha, beta).ConclusionsThe findings of this study suggest that only one night of mild sleep loss significantly increases sleepiness and, importantly, reduces vigilance. In addition, this sleep loss has a clear impact on the physiology of the brain in ways that reflect reduced arousal.SignificanceUnderstanding the neural correlates and cognitive processes associated with loss of sleep may lead to important advancements in identifying and preventing deleterious or potentially dangerous, sleep-related lapses in vigilance.