老年人睡眠时长与抑郁症状的关系

背景 抑郁症严重危害老年人的身心健康,睡眠与抑郁症状的关系已成为研究热点之一,但目前关于睡眠与抑郁症状之间的研究结论存在差异。目的 探讨老年人睡眠时长与抑郁症状之间的关系,为预防老年人出现抑郁症状和延缓已有抑郁症状的老年人病情发展提供参考。方法 采用2018年《中国健康与养老追踪调查》数据库（CHARLS）中8 210名年龄≥60岁老年人的调查结果。按照中文简版流调中心用抑郁量表（CESD-10）评分标准,将老年人分为存在抑郁症状和不存在抑郁症状两组。使用Logistic回归及限制性立方样条模型分析老年人睡眠时长与抑郁症状之间的关联。结果 在8 210名老年人中,检出存在抑郁症状者3 118人（37.98%）,平均每晚睡眠时长为（6.14±2.05）h。睡眠时长与抑郁症状之间存在非线性关联（χ²=412.670,P<0.01,df=4）。在调整了混杂因素后,睡眠时长<6 h、6~6.9 h和≥8 h的老年人出现抑郁症状的风险分别是睡眠时长7~7.9 h老年人的2.971倍（95% CI：2.560~3.449,P<0.01）、1.372倍（95% CI：1.161~1.621,P<0.01）和1.185倍（95% CI：1.009~1.393,P<0.05）。在不同性别及60~69岁组老年人中,未发现睡眠时长≥8 h与抑郁症状检出风险有关（P>0.05）。结论 睡眠时长与抑郁症状存在近似非线性关联,但存在性别和年龄差异。     

Poor sleep quality is associated with worse self-rated health in long sleep duration but not short sleep duration

Unhealthy sleep duration, either short or long, is associated with worse health and central subjective dimensions of sleep and health such as fatigue. It has been argued that the link between sleep duration and health may depend on the quality of the slept hours, and on its functional impact (ie, fatigue). The present study therefore assessed whether the relationship between last night's sleep duration and general self-rated health (SRH) differs as a function of sleep quality, and secondly, whether current fatigue and sleep quality are factors linking sleep duration and SRH.The present cross-sectional dataset involved 1304 individuals (57% female, M_age = 28.8, range 18–79). Participants completed surveys for general SRH, previous night's sleep duration and sleep quality, and current fatigue.Results showed the expected inverted U-shaped (ie, quadratic) relation between last night's sleep duration and SRH and a linear relation between last night's sleep quality and SRH. However, long sleep duration was only associated with poorer SRH in individuals who also reported poor sleep quality. Further, the quadratic relationship between sleep duration and SRH was partially mediated by fatigue and sleep quality.The results of this multi-study analysis suggest that SRH is particularly poor in those who slept both long and with poor quality the night before, while good sleep quality may protect those with a long sleep duration from poor SRH. Thus, last night's long sleep does not seem to be associated with poor subjective health unless it is coupled with poor sleep quality. Furthermore, fatigue and sleep quality are potential pathways linking short and long sleep duration with SRH. Different dimensions of sleep interact in their association with health, and future research will benefit from an integrative approach.     

Association between sleep duration and menstrual cycle irregularity in Korean female adolescents

ObjectiveThe association between sleep and the menstrual cycle in the adolescent population has been scarcely studied. This study aimed to investigate the association between sleep duration and menstrual cycle irregularity among female adolescents using nationwide representative data from the South Korean population.MethodsThis population-based, cross-sectional study used the data collected from Korea National Health and Nutrition Examination Survey 2010–2012, and the data from 801 female adolescents were analyzed. Hierarchical multivariable logistic regression analysis was performed to assess the risk of menstrual cycle irregularity in relation to sleep duration.ResultsSubjects with menstrual cycle irregularity accounted for 15% (N = 120). The mean sleep duration in subjects with menstrual cycle irregularity was significantly shorter than that in those without (p = 0.003). Menstrual cycle irregularity prevalence tended to decrease as sleep duration increased (p for trend = 0.004), which was significantly different based on sleep duration and presence of depressive mood (p = 0.011). Sleep duration ≤5 h per day was significantly associated with increased risk of menstrual cycle irregularity compared with that in the subjects whose sleep duration is ≥8 h per day even after adjusting for confounding variables. The odds ratios of menstrual cycle irregularity tended to increase for shorter sleep duration in all adjusted models.ConclusionThis study found a significant inverse association between sleep duration and menstrual cycle irregularity among Korean female adolescents. Increasing sleep duration is required to improve the reproductive health of female adolescents.     

Association between short sleep duration and metabolic syndrome in Chinese children and adolescents

BackgroundThe relationship between short sleep duration and metabolic syndrome (MetS) in children and adolescents has been inconsistent. This study aimed to examine the association between short sleep duration and MetS in Chinese children and adolescents.MethodsData were from a cross-sectional survey conducted in Jinan, China between September 2013 and November 2014. A total of 1008 children and adolescents aged 6–17 years were included. Sleep duration was self-reported by participants and categorized as normal or short (<9 h in children aged 6–12 years or <8 h in adolescents aged 13–17 years) according to the recommendations of the American Academy of Sleep Medicine. MetS was defined based on the modified criteria of the National Cholesterol Education Program Adult Treatment Panel III.ResultsAfter adjusted for sex, age, parental education levels, and midpoint of sleep, compared with normal sleep duration, short sleep duration was associated with increased odds of MetS (odds ratio [OR]: 1.79, 95% confidence interval [CI]: 1.09–2.95) and abdominal obesity (OR: 1.60, 95% CI: 1.14–2.25). In the subgroups stratified by age and sex, compared with normal sleep duration, short sleep duration was associated with increased odds of abdominal obesity (OR: 2.34, 95% CI: 1.07–5.13) in girls aged 6–12 years; short sleep duration was associated with increased odds of MetS (OR: 2.49, 95% CI: 1.06–5.84), abdominal obesity (OR: 2.30, 95% CI: 1.10–4.82), and high TG (OR: 2.63, 95% CI: 1.11–6.21) in boys aged 13–17 years.ConclusionsShort sleep duration associated with higher odds for MetS in Chinese children and adolescents. Interventions to improve sleep duration could help prevent and control MetS among children and adolescents.     

Animal sleep: a review of sleep duration across phylogeny

Sleep duration and placement within the twenty-four hour day have been primary indices utilized in the examination of sleep function. It is of value, therefore, to evaluate these variables in a wide range of animal species. The present paper examines the literature concerning sleep duration in over 150 animal species, including invertebrates, fish, amphibians, reptiles, birds, and 14 orders of mammals. We first present annotations of almost 200 studies, including number of animals used, photoperiod employed, sleep duration per twenty-four hours and placement of sleep period within the nychthemeron. Both behavioral and electrographic studies are reviewed, as are laboratory and field studies. These data are subsequently presented in a table with representative literature citations for each species. Following the table, a brief discussion is presented concerning some methodological issues which may affect the measurement of sleep duration and some suggestions are made for future examination of sleep duration.     

Association between sleep duration during pregnancy and gestational diabetes mellitus: a meta-analysis

ObjectiveSleep is critical for glucose metabolism. Pregnant women often have sleep disturbances and extreme sleep duration. Investigations of the relationship between sleep duration during pregnancy and gestational diabetes mellitus (GDM) have reported inconsistent results. The present study aimed to meta-analyze the relationship between sleep duration during pregnancy and GDM risk.MethodsWe performed a systematic search of the PubMed, ISI Web of Science, and PsycINFO databases for studies that were published up to October 2017, that reported associations between sleep duration during pregnancy and GDM risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated as the effect sizes for all studies. Heterogeneity and potential publication biases were assessed.ResultsA total of 4366 papers were retrieved, among which seven studies assessed the relationship between sleep duration during pregnancy and GDM development. The seven articles included 18,203 subjects at baseline and 1294 GDM cases during follow-up. Compared to normal sleep duration, extreme sleep duration during early and middle pregnant stages had a close relationship with GDM based upon pooled data from prospective and cross-sectional studies. Prospective results showed that long sleep duration during pregnancy was a risk factor for GDM, but not short sleep duration. Publication biases were found when analyzing the relationship between extreme sleep duration and GDM.ConclusionsExtreme sleep duration during pregnancy is closely associated with GDM. Moreover, long but not short sleep duration can predict the risk of developing GDM. These findings remind us of the importance of sleep duration control during pregnancy and help optimize early strategies for the prevention of GDM.     

Association between change in sleep duration and posttraumatic stress symptoms in natural disaster victims: the mediating role of resilience

ObjectiveThis study investigated the association between changes in sleep duration after disaster and post-traumatic stress disorder (PTSD) symptoms and the mediating role of resilience on the association.MethodsData were collected from 2951 Korean adults who were victims of a natural disaster and did not have any mental or medical illnesses before the event. They completed a long-term survey on changes in life for disaster victims using computer-aided personal interviews. Changes in sleep duration before and one month after experiencing a disaster were assessed using a self-reported questionnaire. Resilience levels and PTSD symptoms were measured using the Brief Resilience Scale and the Impact of Event Scale – Revised, respectively, and more than 33 of the IES-R score items were defined as significant PTSD symptoms. Multivariate logistic regression was used to examine the associations between changes in sleep duration and PTSD symptoms. Additionally, mediating studies were conducted to identify the role of resilience on the association.ResultsCompared with participants without significant PTSD symptoms, those with PTSD symptoms were more likely to be older and female (group without significant PTSD symptom: mean age = 56.12 ± 18.70 years, female sex = 49.24%; group with significant PTSD symptoms: mean age = 60.88 ± 15.66 years, female sex = 59.52%). Compared with disaster victims without changes in sleep duration, those who had shorter sleep duration after disaster had a higher risk of significant PTSD symptoms (OR = 2.89, 95% Cl = 2.31–3.62, p < 0.001). In the mediating study, resilience level significantly mediated the relationship between reduced sleep duration and PTSD symptoms (direct effect: β = 0.208, 95% Cl = 0.166–0.250, p < 0.001; indirect effect: β = 0.007, 95% Cl = 0.002–0.011, p < 0.001; total effect: β = 0.215, 95% Cl = 0.173–0.257, p < 0.001).ConclusionThis study revealed that individuals with reduced sleep duration after disaster had a higher risk of PTSD symptoms, while those with increased sleep duration did not. In addition, mediating effects of resilience level on the relationship between reduced sleep duration and significant PTSD symptoms were observed.     

Characteristics associated with parental estimates of sleep duration in children with autism spectrum disorders

BackgroundSleep problems are common in individuals with ASD. This study examined the relationships between bedtime consistency, cognitive functioning, comorbid diagnoses, intervention, demographics and sleep duration in children with ASD.MethodCross-sectional data from 1683 children with ASD in the 2016 and 2017 National Survey of Children's Health were analyzed. The sample was 80 % male, 46 % non-Hispanic white, and mean age was 10.5 (SD 4.1) years. All data were parent report. Multiple linear regression was performed.ResultsASD severity was associated with shorter sleep duration, and bedtime consistency was associated with longer sleep duration. Age moderated the effects of both bedtime consistency and ADD/ADHD on sleep duration. Both the positive effect of bedtime consistency and the negative effect of ADD/ADHD on sleep duration became less pronounced with age.ConclusionAlthough the challenges related to sleep and behavior may differ by age of the child, bedtime consistency could be a good target to improve sleep duration for all children with ASD. Future studies, especially longitudinal studies, on sleep habits and sleep hygiene, in conjunction with other measures of sleep patterns (e.g., night wakings) and correlates of sleep problems, may provide further evidence for the importance of good sleep practices and guide sleep treatment in children with ASD.     

Association between sleep duration and rupture of intracranial aneurysms: A single-center retrospective study

ObjectiveTo assess the relationship between sleep duration and risk of rupture of intracranial aneurysms (IAs).MethodsAccording to our inclusion and exclusion criteria, 683 patients admitted to Beijing Tiantan Hospital were included in this study. There were 201 patients in the ruptured group and 482 patients in the unruptured group. Sleep duration was divided into three levels: ≥8 h (long), 6–8 h (normal), ≤6 h (short). Correlation between different sleep duration and rupture of IAs was evaluated by univariate and multivariate regression analysis.ResultsThe results of multivariate analysis demonstrated that there was a statistical difference between sleep duration of ≤6 h and sleep duration ≥8 h (OR = 1.76, CI = [1.08–2.87], p = 0.025). There was no statistically significant difference between the group with sleep duration of 6–8 h and sleep duration of ≥8 h (OR = 1.04, CI = [0.65–1.67], p = 0.857).ConclusionShort sleep duration (≤6 h) may be related to the rupture of intracranial aneurysms. The reason for this correlation is not yet clear. We suspect that it may be caused by a series of physiological changes caused by reduced sleep.     

Association between reduced serum BDNF levels and insomnia with short sleep duration among female hospital nurses

ObjectivePrevious studies have suggested that brain-derived neurotrophic factor (BDNF) is associated with sleep regulation in humans. However, its relationship with self-reported sleep problems has not been clarified. The aim of the present study was to examine the association between serum BDNF levels and sleep problems among hospital nurses.MethodsParticipants were enrolled from among nurses working at a general hospital in Tokyo, Japan. Data from 577 women (age: 35.45 ± 10.90 years) were analyzed. This cross-sectional survey was conducted from November to December 2015. Serum BDNF concentrations were evaluated. Participants completed a self-reported questionnaire on sleep including the presence or absence of insomnia symptoms (ie, difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening [EMA]), and sleep duration. Insomnia with short sleep duration (ISS) was defined as: DIS, or DMS, or EMA; and <6 h sleep duration.ResultsAmong 577 participants, 21.3% reported insomnia, 41.4% slept less than 6 h, and finally 12.5% suffered from ISS. Serum BDNF levels were significantly lower in subjects with ISS than in those without ISS. The serum BDNF levels in insomniacs were significantly lower than in non-insomniacs for short sleep duration (<6 h), while serum BDNF levels did not differ between insomniacs and non-insomniacs for normal sleep duration (≥6 h).ConclusionThis is the first documented study to indicate that ISS is associated with reduced serum BDNF levels. These results may lead to clarification of the underlying pathophysiological relationship between BDNF and poor sleep.     

Associations of accelerometer-based sleep duration and self-reported sleep difficulties with cognitive function in late mid-life: the Finnish Retirement and Aging Study

ObjectivesPrior evidence suggests that sleep duration and sleep difficulties may be associated with cognitive function in old age, but little is known about the sleep–cognition association in late mid-life. Our aim was to examine the associations of accelerometer-based sleep duration as well as subjective sleep difficulties with different domains of cognitive function among aging workers.MethodsThe study population consisted of 289 participants (mean age 62.4 years, SD 1.02; 83% women) from the Finnish Retirement and Aging Study (FIREA). Sleep difficulties were measured using Jenkins Sleep Problem Scale (difficulties falling asleep, difficulties maintaining sleep, waking up too early in the morning, and nonrestorative sleep). Sleep duration was measured with wrist-worn accelerometer and self-report, and participants were divided into short (<7 h/night), mid-range (7–9 h/night) and long (≥9 h/night) sleepers. Participants underwent extensive cognitive testing covering three domains: (1) memory, (2) executive function, and (3) attention and information processing.ResultsGreater difficulties in waking up too early in the morning were associated with poorer executive function measured with Spatial Working Memory (SWM) test (p = 0.005). Additionally, nonrestorative sleep was associated with poorer executive function measured with Trail Making Test, B–A, (p = 0.036) and borderline significantly with lower SWM (p = 0.056). Compared to mid-range sleepers, long sleepers tended to have poorer cognitive function (all memory function tests and SWM), but the associations were not statistically significant due to small number of long sleepers.ConclusionsSubjective sleep difficulties may be linked to poorer executive function in a relatively healthy population of older workers in their 60 s. Thus, promoting good sleep quality may translate into better cognitive health in late mid-life.     

Effects of atmospheric particulate matter pollution on sleep disorders and sleep duration: a cross-sectional study in the UK biobank

BackgroundSleep disorder prevalence exhibited a six-fold relative increase from 2000 to 2010 in the United States. Sleep problems could increase the risk of stroke, cardiovascular disease, diabetes and cancer. Objective short sleep duration is associated with increased mortality. Obesity, smoking and sex differences could influence sleep disorders and sleep duration. The health effects of atmospheric particulate matter (PM) pollution are of great concern. However, a large general population-based study with abundant demographic and lifestyle information is needed to confirm the effect of PM pollution on sleep disorders and sleep duration.MethodsInformation on PM air pollution, demographics and other related factors was obtained from the UK Biobank. Subjects’ characteristics were described as the means and 95% confidence intervals (95% CIs) for continuous variables and counts (percentages) for categorical variables. In the case–control study of sleep disorders, univariate analysis, single-pollutant models and a four-pollutant model with logistic regression were performed to estimate the odds ratio (OR) of the risk factors. For sleep duration, univariate analysis, single-pollutant models and a four-pollutant model with linear regressions were carried out to assess the effect of the factors. Sensitivity analysis was performed by data imputation and study population change.ResultsThere were 5976 cases and 97,160 controls included in the case–control study of sleep disorders. For sleep duration analysis, most of the participants had environmental PM data, and 457,358 participants were selected. The single-pollutant models showed that the OR of PM_2.5 for sleep disorders was 2.39 (95% CI: 1.64–3.48) for every 10 μg/m³ increase. PM_2.5 and PM₁₀ reduced sleep duration by 0.14 (95% CI: 0.10–0.18) and 0.12 (95% CI: 0.10–0.14) hours for every 10 μg/m³ increase, respectively. Four-pollutant models showed that the OR of PM_2.5 for sleep disorders was 4.42 (95% CI: 2.36–8.26) for every 10 μg/m³ increase. PM₁₀ appeared to reduce sleep duration by 0.09 (95% CI: 0.06–0.12) hours for every 10 μg/m³ increase. The main results showed good robustness after sensitivity analysis.ConclusionsPM_2.5 was a risk factor for sleep disorders. PM_2.5 and PM₁₀ reduced sleep duration. A reduction in particulate matter exposure may decrease the risk of sleep disorders and improve sleep duration.     

Cohort effects associated with reduced sleep duration in adolescents

ObjectiveThe purpose of this study is to examine how the sleep duration changes during adolescence across the seventh, eighth, ninth, and 10th grade periods, and to determine whether there is a difference between the cohorts.MethodFor these purposes, we used the latent growth curve modeling and the multi-group analysis involving 2081 students (2000-birth cohort data) and 2254 students (1997-birth cohort data) who participated in the Korean Children and Youth Panel Survey. The data were collected using a stratified multistage cluster sampling method.ResultsSleep duration became shorter as age increased. Furthermore, the sleep duration of the 2000-birth cohort became shorter than the sleep duration of the 1997-birth cohort. Specifically, the mean value of the initial sleep duration of the 2000-birth cohort was 8.09 h, which was significantly shorter than the initial value 8.36 h of the sleep duration of the 1997-birth cohort. In addition, multi-group analysis revealed that the trajectories of sleep duration and its predictors were varied by cohort. Specifically, parent supervision, peer relationship, and electronic media factors (smartphone overuse, time spent on using computer and playing games) explained the cohort effect.ConclusionThese findings suggest that environmental factors such as increasing use of electronic media or pressure regarding higher education to adolescents could be associated with reduced sleep duration.     

Obstructive sleep apnea,sleep duration and chronic kidney disease in patients with coronary artery disease

BackgroundLimited evidence is available addressing the potential role of sleep disorders on renal function. Here, we aimed to explore the associations of obstructive sleep apnea (OSA) and sleep duration (SD) with renal function in subjects with high cardiovascular risk.MethodsConsecutive subjects with coronary artery disease (CAD) underwent clinical evaluation, sleep study to define OSA and one-week wrist actigraphy to objectively measure SD. OSA was defined by an apnea-hypopnea index (AHI) of ≥15 events/hour. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI equation. We analyzed the associations of OSA and SD with continuous eGFR values and according to the presence of CKD (eGFR<60 mL/min/1.73 m²) after adjusting for multiple confounding factors.ResultsWe studied 242 subjects (62.8% men). The frequency of OSA was 55.4% and the median SD was 412.8 (363.4–457.25) min. There was no difference in the eGFRs between participants with and without OSA (69.3 ± 19.1 vs. 74.6 ± 19.3 mL/min/1.73 m², p = 0.72) and the rate of eGFR <60 mL/min/1.73 m² (34.3% vs. 25.9%; p = 0.21). Similarly, we did not find differences in patients in eGFR for those with SD ≥ 6 h versus SD < 6 h (72.5 ± 20.3 vs. 71.4 ± 19.1 mL/min/1.73 m², p = 0.72). In the linear regression analysis, AHI was independently associated with an eGFR<60 mL/min/1.73 m² in the unadjusted model [−0.15 (-0.27 to −0.04)], (P = 0.01), but not in the adjusted models. Analyses of continuous SD or the stratification in SD ≥ 6 h or <6 h also revealed neutral results on eGFR.ConclusionOSA severity and SD were not independently associated with CKD in subjects with CAD.     

Progesterone reduces wakefulness in sleep EEG and has no effect on cognition in healthy postmenopausal women

Sleep is frequently impaired in postmenopausal women. Progesterone prompted benzodiazepine-like effects on sleep EEG in young normal male subjects. Aim of this study was to test if treatment with progesterone improves sleep after menopause. A randomised double blind crossover design study with 2 treatment intervals of 21 days duration separated by a 2 weeks washout was performed. An oral dose of 300mg micronized progesterone was given each for 21 days. At the beginning and the end of the two intervals a sleep EEG was recorded and cognitive performance was assessed in 10 healthy postmenopausal women (age: 54-70 years). Progesterone treatment led to a decrease of intermittent time spent awake. During the first third of the night rapid eye movement (REM) sleep increased. The spectral analysis of the EEG resulted in no significant differences of the power spectra. Progesterone did not affect cognitive performance. In summary progesterone demonstrated a distinct sleep promoting effect by reduction of time of wake without impairing cognitive functions during daytime. As possible mechanisms of progesterone a GABA-agonistic effect and the regulation of gene expression via the progesterone receptor are discussed. Progesterone might be useful in the treatment of sleep disturbances of postmenopausal women.     

Decreases in self-reported sleep duration among U.S. adolescents 2009–2015 and association with new media screen time

Study objectivesInsufficient sleep among adolescents carries significant health risks, making it important to determine social factors that change sleep duration. We sought to determine whether the self-reported sleep duration of U.S. adolescents changed between 2009 and 2015 and examine whether new media screen time (relative to other factors) might be responsible for changes in sleep.MethodsWe drew from yearly, nationally representative surveys of sleep duration and time use among adolescents conducted since 1991 (Monitoring the Future) and 2007 (Youth Risk Behavior Surveillance System of the Centers for Disease Control; total N = 369,595).ResultsCompared to 2009, adolescents in 2015 were 16%–17% more likely to report sleeping less than 7 h a night on most nights, with an increase in short sleep duration after 2011–2013. New media screen time (electronic device use, social media, and reading news online) increased over this time period and was associated with increased odds of short sleep duration, with a clear exposure–response relationship for electronic devices after 2 or more hours of use per day. Other activities associated with short sleep duration, such as homework time, working for pay, and TV watching, were relatively stable or reduced over this time period, making it unlikely that these activities caused the sudden increase in short sleep duration.ConclusionsIncreased new media screen time may be involved in the recent increases (from 35% to 41% and from 37% to 43%) in short sleep among adolescents. Public health interventions should consider electronic device use as a target of intervention to improve adolescent health.     

Associations between pain,objective sleep efficiency and cognition in patients with implantable cardioverter defibrillators

IntroductionPatients with implantable cardioverter defibrillators (ICDs) frequently experience sleep disruption. Prior work shows associations between objective (actigraphic) sleep and cognition in these patients, but whether pain affects associations between measures of sleep fragmentation (eg, sleep efficiency, SE) and cognition is unknown. The present study examined independent and interactive associations between objective SE and pain on cognitive performance in patients with ICDs.MethodsA total of 37 patients with ICDs (M_age = 60.0, SD = 12.4) and self-reported sleep disturbance completed 14 days of actigraphy. Average SE was computed [(average total sleep time/average time in bed) × 100%]. Patients completed the Short Form 36 Health Survey pain section, and computerized tasks measuring executive functioning (letter series, N-Back task), sustained attention/processing speed (symbol digit modalities test, SDMT), and simple reaction time. Multiple linear regressions examined whether SE independently predicted or interacted with pain ratings to predict cognitive performance.ResultsSE interacted with pain to predict SDMT performance, accounting for 12% unique variance. In patients reporting worse pain, higher SE was associated with better SDMT performance. Similar patterns of association on SDMT were not observed in patients with average or low pain. SE and pain ratings did not independently predict SDMT performance. Performance on other cognitive tasks was not associated with any predictors.ConclusionBetter sleep efficiency may play an important role in improving sustained attention/processing speed in patients with ICDs and perceived severe pain. Future research should examine whether interventions aimed at improving sleep fragmentation provide benefit to lower order cognition, particularly in patients with worse pain.     

Effects of sleep duration and weekend catch-up sleep on falling injury in adolescents: a population-based study

ObjectiveThis population-based study aimed to determine the effects of sleep deprivation and compensatory weekend catch-up sleep on the risk of falls in adolescents.MethodsData from the 2013 Korean Youth Risk Behavior Web-based Survey on 57,225 adolescents were investigated. Demographic, socioeconomic, sleep-related, health-related behavioral, and psychological variables were compared between fallers (n = 7346) and non-fallers (n = 49,879). Multivariate logistic regression analysis using a hierarchical model was carried out to identify sleep-related factors (eg, sleep duration, longer weekend catch-up sleep) independently contributing to the risk of falls.ResultsCompared to non-fallers, fallers were associated with a shorter sleep duration (p = 0.001) and later bedtimes on weekdays and weekends (p < 0.001). An average sleep duration of ≤ 5 h (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.12–1.34) and of 6 h (OR 1.12, CI 1.03–1.21) were associated with an increased risk of falls. By contrast, an average sleep duration of ≥ 9 h (OR 0.90, CI: 0.82–0.99) and longer weekend catch-up sleep (OR 0.94, CI: 0.89–0.99) were associated with a decreased risk of falls.ConclusionOur results corroborate previous suggestions that short sleep duration is a major risk factor for falls among adolescents. Moreover, our study provided a novel finding that longer sleep duration and longer weekend catch-up sleep may have a protective effect against falls. Our findings have important public health implications that modifying school schedules to increase sleep duration could reduce unintentional falls and injuries in school-aged adolescents.     

Association between actigraphy-based sleep duration variability and cardiovascular risk factors – Results of a population-based study

BackgroundAlthough a few studies suggest an adverse effect of sleep duration variability on cardiovascular risk factor, others did not and this association remains controversial. Moreover, most studies were non-representative of the general population, used different sleep duration variability measures, and relied on self-reported sleep duration. We aimed to assess the association between different, actigraphy-based sleep duration variability measures and cardiovascular risk factors in a population-based sample.MethodsIn a middle-aged population-based cohort, 2598 subjects had data on sleep duration variability measured by actigraph over 14 days. Multivariable logistic regressions were performed to assess the relationship between different sleep duration variability measures [ie, night-to-night variability (NNV), range between shortest and longest sleep duration (RSL), range between average weekday and weekend sleep duration (RWW)] and cardiovascular risk factors including obesity, diabetes and hypertension.ResultsSubjects with highest sleep duration variability - measured as NNV, RSL and RWW, were more likely to be obese. These associations robust in most but not all sensitivity analyses, and no associations between sleep duration variability measures and diabetes or hypertension were found.ConclusionThere is a possible association between high sleep duration variability and obesity, although results were not robust in all sensitivity analyses. Further, no associations between sleep duration variability and other cardiovascular risk factor such as diabetes or hypertension were found.     

The association of nighttime sleep duration and quality with chronic kidney disease in middle-aged and older Chinese: a cohort study

ObjectiveThis cohort study aimed to assess the associations between sleep duration and quality with the risk of incident chronic kidney disease (CKD) in middle-aged and older Chinese.MethodsWe used the 2011 and 2015 surveys of the China Health and Retirement Longitudinal Study (CHARLS). Nighttime sleep duration was categorized into five groups: ≤4, (4–6], (6–8], (8–10], and >10 h/night. Sleep quality was assessed by restless days in the past week (<1, 1–2, 3–4, and 5–7 days/week). Multivariate logistic regression was used to assess the association between sleep duration and quality with incident CKD.ResultsA total of 11,339 participants free of CKD at baseline were included in this study. After four years follow-up, the incidence of CKD was 7.8%. There was a “U-shaped” association between sleep duration and risk of CKD. Compared to 6–8 h of nighttime sleep duration, those who slept ≤4 h/night (RR: 1.639, 95% CI: 1.287–2.087) or >10 h/night (RR: 2.342, 95% CI: 1.007–5.451) had increased risk of developing CKD after adjustment for confounders. Participants with 5–7 restless days per week had significantly increased risk of CKD (adjusted RR: 1.686, 95% CI: 1.352–2.102), compared to those who rarely or never had a restless sleep.ConclusionsExtreme nighttime sleep duration and poor sleep quality were associated with increased risk of CKD in middle-aged and older Chinese. Obtaining an optimal nighttime sleep duration and better sleep quality might reduce the risk of CKD.