Specific Sleep Parameters Research Articles

Exploring the Congruence of actigraphy and the Pediatric Autism Insomnia rating Scale

Objective/BackgroundInsomnia is common in children with autism spectrum disorder (ASD). We recently developed and validated the 21-item Pediatric Autism Insomnia Rating Scale (PAIRS). This report explores the associations and agreements between actigraphy and PAIRS. Participants MethodsChildren with ASD, with and without sleep problems, were assessed with a battery of parent-rated and clinician measures (N = 134). In a subset (n = 70), a wrist-worn actigraph measured sleep for five consecutive nights. Parents completed logs for scoring sleep intervals. Spearman correlations evaluated associations with the PAIRS and actigraphy indices (sleep onset latency = SOL, wake after sleep onset = WASO, total sleep time = TST, sleep efficiency = SE%). Agreements on “poor sleepers” based on PAIRS total score (≥33) and conventional thresholds for TST and SE% were evaluated with Cohen's Kappa and McNemar's test. ResultsActigraphy data were averaged over 4.64 ± 0.68 nights in 70 children (mean age = 7.3 ± 2.9, 74.3 % male). There were no significant correlations between PAIRS and any actigraphy indices. On TST, 48.6 % (n = 34) and on SE% 52.9 % (n = 37) were classified as “poor sleepers” compared to 32.9 % (n = 23) on PAIRS (kappa = 0.11 for TST and 0.27 for SE%). P-values on McNemar's Chi square test for PAIRS with TST and with SE% were 0.072 and 0.011, respectfully. ConclusionsThese results suggest that actigraphy and PAIRS do not agree. Actigraphy TST captures movement and an estimate of specific sleep parameters. PAIRS is a broader measure that incorporates sleep disturbance and sleep-related impairment.

The Relationships of Specific Cognitive Control Abilities with Objective and Subjective Sleep Parameters in Mild Cognitive Impairment: Revealing the Association between Cognitive Planning and Sleep Duration.

This study aimed to examine the associations between specific sleep parameters and specific aspects of cognitive functioning in individuals diagnosed with mild cognitive impairment (MCI), compared with healthy controls (HCs) by using cognitive, subjective, and objective sleep measures. A total of 179 participants were enrolled, all aged ≥ 65 years (mean age = 70.23; SD = 4.74) and with a minimum of six years of education (mean = 12.35; SD = 3.22). The sample included 46 HCs (36 females), 75 individuals with amnestic MCI (aMCI) (51 females), and 58 individuals with non-amnestic MCI (naMCI) (39 females). Inhibition, cognitive flexibility as a combined application of inhibitory control and set shifting or task/rule switching, and planning were examined. The following D-KEFS subtests were administered for their evaluation: Verbal Fluency Test, Color-Word Interference Test, and Tower Test. Self-reported sleep questionnaires (Athens Insomnia Scale, Stop-Bang questionnaire, and Pittsburg Sleep Quality Index) were used for subjective sleep assessments. Actigraphy was used for objective sleep measurements. Mixed-measures ANOVA, MANOVA, and one-way ANOVA, as well as the Scheffe post hoc test, were applied to the data. The results showed that the three groups exhibited statistically significant differences in the Tower Test (total achievement score, total number of administered problems, and total rule violations). As regards objective sleep measurements, the total sleep time (TST) was measured using actigraphy, and indicated that there are significant differences, with the HC group having a significantly higher mean TST compared to the naMCI group. The relationships evaluated in the TST Tower Test were found to be statistically significant. The findings are discussed in the context of potential parameters that can support the connection between sleep duration, measured as TST, and cognitive planning, as measured using the Tower Test.

Effects of probiotics on sleep parameters: A systematic review and meta-analysis

AimAlthough sleep is essential for maintaining good health and well-being, sleep disorders are becoming increasingly prevalent. Probiotics may play a role in sleep regulation; therefore, this study aimed to provide a comprehensive overview of the effects of probiotics on sleep parameters. MethodsWe conducted a systematic literature review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Relevant placebo-controlled randomized controlled trials examining the effects of probiotics on sleep outcomes were identified through systematic searches in the PubMed, Cochrane Library, and Ichushi databases. Data were extracted from eligible studies and the risk of bias was assessed. Statistical analyses were performed to assess the effects of probiotics on various sleep-related variables. ResultsFifteen randomized controlled trials were included in this review. The decrease in Pittsburgh Sleep Quality Index (PSQI) scores in the probiotics group was significantly lower than that in the placebo group after 4–6 weeks and 8–16 weeks, indicating improved sleep quality. The Oguri-Shirakawa-Azumi (OSA) sleep inventory score was also decreased in the probiotics group for Factor 1 “sleepiness on rising” and Factor 4 “refreshing,” indicating improved sleep quality. Some studies however, showed a risk of bias. ConclusionThis systematic review and meta-analysis indicated that probiotics may improve sleep quality, as measured by the PSQI and OSA sleep inventory. However, further research is needed to better understand the effects of probiotics on specific sleep parameters and address the limitations of existing studies.

Associations Between Multiple Dimensions of Sleep and Mood During Early Adolescence: A Longitudinal Daily Diary Study.

Prior research has observed reciprocal associations between sleep and mood. However, these findings are primarily based on the examination of one or two aspects of sleep behaviors (e.g., duration, quality), neglecting how multiple dimensions of sleep (particularly indicators pertinent to adolescence, e.g., sleep variability) are linked to adolescent mood both daily and longitudinally. Drawing on a multidimensional framework for sleep, this study addressed the knowledge gap by examining the directionality of and differential effects for associations between multiple dimensions of sleep and mood during early adolescence. Participants were 273 Chinese early adolescents (34.39% girls; Mage = 11.57, SD = 1.31), who filled out a pre-survey on demographics (T1) and 7-day diaries on sleep (i.e., duration, quality, disturbance, and latency) and mood (i.e., positive and negative mood). Adolescents completed another wave of diary reports 1 year later (T2). Findings revealed both bidirectional and unidirectional, within-person effects depending on specific sleep parameters, suggesting differential associations between multiple dimensions of sleep and mood. Specifically, on days when adolescents had longer sleep latency and greater disturbance than usual, they reported higher negative mood the next day, whereas higher negative mood was linked to poorer sleep quality the next day. The longitudinal investigation found that greater variability in sleep quality at T1 was associated with higher negative mood at T2. These findings underscore the importance of understanding the complex interplay between sleep and mood by examining the directionality of and differential effects for the daily and longer-term associations between multiple dimensions of sleep and mood among early adolescents.

Which Are the Most Reliable Sleep Parameters that Predict Cognitive Decline and Alzheimer's Disease?

Sleep disorders can represent an independent risk factor for cognitive decline and Alzheimer's disease (AD). It remains to be clarified if specific sleep parameters could be considered biomarkers of AD-related neurodegeneration. Several studies solely investigated the results of cross-sectional research, without providing conclusive evidence. Few longitudinal studies showed some inconsistencies in macrostructural and microstructural sleep findings. Methodological heterogeneity among studies can explain the discrepancies in the results. Moreover, the polysomnographic findings are usually related to only one-night recording. The combination of actigraphic recordings with sleep EEG monitoring for some consecutive days should be considered in future research.

Examining the Impact of Physical Activity on Sleep Quality in Children With ADHD

Objective: Sleep problems have been commonly observed in children with attention deficit hyperactivity disorder (ADHD). The aim of current study was to investigate the impact of physical activity on sleep quality in young adolescent with attention deficit hyperactivity disorder. Method: A total of 33 children diagnosed with attention deficit hyperactivity disorder (mean age = 10.12 years) were randomized into intervention group and control group respectively. Mention the intervention detail here. Four specific sleep parameters, including sleep efficiency, sleep onset latency, sleep duration, and wake after sleep onset, were assessed before and after the intervention period in both groups. Results: Results revealed the significant improvements in sleep efficiency, sleep onset latency and wake after sleep onset in the intervention group but not in the control group. Conclusion: Current findings highlight the benefits of PA on enhancing sleep quality among children with ADHD.

Effect of house dust mite allergen on sleep parameters and sleep quality.

The role of nasal problems such as allergic rhinitis in the development of obstructive sleep apnea (OSA) is controversial. The purpose of this study was to analyze the effects of house dust mite (HDM) allergen on sleep-related problems. In a retrospective study patients were classified according to the house dust mite (HDM)-related specific immunoglobulin E (IgE) level into a low HDM-IgE group (group A) and a high HDM-IgE group (group B). Polysomnographic indices, OSA severity, and self-administered questionnaire results were compared between groups. Correlational analysis was used to identify associations between specific IgE values and sleep parameters related to respiratory events. A total of 327 patients were enrolled.N1 stage ratio, apnea index, and apnea-hypopnea index were significantly higher in group B (P = 0.010, 0.003, and 0.002 respectively) than in group A. N2 stage ratio, and lowest and mean oxygen saturation were significantly lower in group B (P = 0.001, 0.001, and < 0.001 respectively). After propensity score matching, the apnea index and lowest and mean oxygen saturation remained significantly different (P = 0.005, 0.005, and 0.001 respectively). Patients in group B were more likely to have severe OSA and worse subjective sleep quality. In correlational analysis, lowest and mean oxygen saturation were significantly negatively correlated with specific IgE values. A high HDM-specific IgE level was associated with the occurrence of respiratory events and oxygen desaturation during sleep, and with the presence of severe OSA, as well as poorer subjective sleep quality.

Investigating the influence of an adjustable zoned air mattress on sleep: a multinight polysomnography study.

A comfortable mattress should improve sleep quality. In this study, we sought to investigate the specific sleep parameters that could be affected by a mattress and explore any potential differences between the effects felt by each sex. A total of 20 healthy young adults (10 females and 20 males; 22.10 ± 1.25 years) participated in the experiments. A smart adjustable zoned air mattress was designed to maintain comfortable support, and an ordinary mattress was used for comparison. The participants individually spent four nights on these two mattresses in four orders for polysomnography (PSG) scoring. Sleep architecture, electroencephalogram (EEG) spectrum, and heart rate variability (HRV), which reflect the central and autonomic nervous activities, were used to compare the difference between the two mattresses. An individual difference exited in sleep performance. The modes of influence of the mattresses were different between the sexes. The adjustable air mattress and the increase in experimental nights improved female participants' sleep efficiency, while male participants exhibited a smaller response to different mattresses. With an increasing number of experiment nights, both sexes showed increased REM and decreased N2 proportions; the N3 sleep proportion decreased in the male participants, and the heart rate decreased in both sexes. The performance of the EEG spectrum supports the above results. In addition, the adjustable air mattress weakened automatic nerve activity during N3 sleep in most participants. The female participants appeared to be more sensitive to mattresses. Experiment night was associated with psychological factors. There were differences in the results for this influence between the sexes. This study may shed some light on the differences between the ideal sleep environment of each sex.

Estimation of Bedtimes of Reddit Users: Integrated Analysis of Time Stamps and Surveys.

Individuals with later bedtimes have an increased risk of difficulties with mood and substances. To investigate the causes and consequences of late bedtimes and other sleep patterns, researchers are exploring social media as a data source. Pioneering studies inferred sleep patterns directly from social media data. While innovative, these efforts are variously unscalable, context dependent, confined to specific sleep parameters, or rest on untested assumptions, and none of the reviewed studies apply to the popular Reddit platform or release software to the research community. This study builds on this prior work. We estimate the bedtimes of Reddit users from the times tamps of their posts, test inference validity against survey data, and release our model as an R package (The R Foundation). We included 159 sufficiently active Reddit users with known time zones and known, nonanomalous bedtimes, together with the time stamps of their 2.1 million posts. The model's form was chosen by visualizing the aggregate distribution of the timing of users' posts relative to their reported bedtimes. The chosen model represents a user's frequency of Reddit posting by time of day, with a flat portion before bedtime and a quadratic depletion that begins near the user's bedtime, with parameters fitted to the data. This model estimates the bedtimes of individual Reddit users from the time stamps of their posts. Model performance is assessed through k-fold cross-validation. We then apply the model to estimate the bedtimes of 51,372 sufficiently active, nonbot Reddit users with known time zones from the time stamps of their 140 million posts. The Pearson correlation between expected and observed Reddit posting frequencies in our model was 0.997 on aggregate data. On average, posting starts declining 45 minutes before bedtime, reaches a nadir 4.75 hours after bedtime that is 87% lower than the daytime rate, and returns to baseline 10.25 hours after bedtime. The Pearson correlation between inferred and reported bedtimes for individual users was 0.61 (P<.001). In 90 of 159 cases (56.6%), our estimate was within 1 hour of the reported bedtime; 128 cases (80.5%) were within 2 hours. There was equivalent accuracy in hold-out sets versus training sets of k-fold cross-validation, arguing against overfitting. The model was more accurate than a random forest approach. We uncovered a simple, reproducible relationship between Reddit users' reported bedtimes and the time of day when high daytime posting rates transition to low nighttime posting rates. We captured this relationship in a model that estimates users' bedtimes from the time stamps of their posts. Limitations include applicability only to users who post frequently, the requirement for time zone data, and limits on generalizability. Nonetheless, it is a step forward for inferring the sleep parameters of social media users passively at scale. Our model and precomputed estimated bedtimes of 50,000 Reddit users are freely available.

603 Socioeconomic Status and Caregiver Perception of Young Children’s Sleep

Abstract Introduction Socioeconomic status (SES) has been associated with variation in child sleep problems, but few studies have examined variation by SES in caregiver-reported early childhood sleep problems, patterns, and health behaviors. We hypothesized that, compared to higher-SES caregivers, lower-SES caregivers would report poorer sleep outcomes and sleep health behaviors, but lower rates of caregiver-perceived sleep problems. Methods A total of 309 caregivers (97% parents) of young children (M child age=3.59 years; 53.1% girls; 15% non-Hispanic/Latinx White, 57% non-Hispanic/Latinx Black, 20% Hispanic/Latinx White, 8% Hispanic/Latinx Black) completed the Brief Child Sleep Questionnaire. SES was measured via income level (lowest=$0-$20,000; middle= $20,001-$50,000; highest= $50,001 or greater). Results The prevalence of a caregiver-reported child sleep problem was similar across SES (17.6% of lowest SES group, 8.8% of middle, and 15.5% of highest, p&amp;gt;.05). However, ANCOVA models covarying for child race/ethnicity, age, caregiver age and education indicated sleep outcomes varied by SES. Caregivers in the lowest SES group reported significantly longer child sleep onset latency (SOL) than the middle or highest groups (p=.008), more frequent night wakings than those of middle SES (p=.009), and longer night waking duration than those of the highest SES, (p=.047). There were no significant differences by SES for child bedtime, total nighttime sleep, and total (24-hour) sleep duration. Logistic regression models with the same covariates showed no variation by SES for sleep behaviors, including caffeine consumption, presence of bedroom electronics, and bedtime resistance. Within each SES group, logistic regression models indicated that increased night wakings were uniquely associated with greater likelihood of endorsing a child sleep problem in the middle SES (p=.045) and highest SES groups (p=.040), but not in the lowest SES group. Conclusion Although caregiver-reported child sleep problems did not significantly differ across SES, lower-SES caregivers reported longer child sleep onset latency and increased number and duration of night wakings. Furthermore, night wakings were associated with perceived sleep problems, but only in middle and highest SES families. Clinicians should consider specific sleep parameters, such as SOL and night wakings, in addition to caregiver-reported child sleep problems when assessing and addressing child sleep problems, especially in lower-SES families. Support (if any) Funding: NIH K23HD094905 (AAW)

237 Sleep disturbances, online instruction, and learning during COVID-19: evidence from 4148 adolescents in the NESTED study

IntroductionCOVID-19 fundamentally altered education in the United States. A variety of in-person, hybrid, and online instruction formats took hold in Fall 2020 as schools reopened. The Nationwide Education and School in TEens During COVID (NESTED) study assessed how these changes impacted sleep. Here we examined how instruction format was associated with sleep disruption and learning outcomes.MethodsData from 4148 grade 6-12 students were included in the current analyses (61% non-male; 34% non-white; 13% middle-school). Each student’s instructional format was categorized as: (i) in-person; (ii) hybrid [≥1 day/week in-person]; (iii) online/synchronous (scheduled classes); (iv) online/asynchronous (unscheduled classes); (v) online-mixed; or (vi) no-school. Sleep disturbances (i.e., difficulty falling/staying asleep) were measured with validated PROMIS t-scores. A bootstrapped structural equation model examined how instructional format and sleep disturbances predict school/learning success (SLS), a latent variable loading onto 3 outcomes: (i) school engagement (ii) likert-rated school stress; and (iii) cognitive function (PROMIS t-scores). The model covaried for gender, race-ethnicity, and school-levelResultsOur model fit well (RMSEA=.041). Examining total effects (direct + indirect), online and hybrid instruction were associated with lower SLS (b’s:-.06 to -.26; p’s<.01). The three online groups had the strongest effects (synchronous: b=-.15; 95%CI: [-.20, -.11]; asynchronous: b=-.17; [-.23, -.11]; mixed: b=-.14; [-.19, -.098]; p’s<.001). Sleep disturbance was also negatively associated with SLS (b=-.02; [-.02, -.02], p<.001). Monte-carlo simulations confirmed sleep disturbance mediated online instruction’s influence on SLS. The strongest effect was found for asynchronous instruction, with sleep disturbance mediating 24% of its effect (b = -.042; [-0.065, -.019]; p<.001). This sleep-mediated influence of asynchronous instruction propagated down to each SLS measure (p’s<.001), including a near 3-point difference on PROMIS cognitive scores (b = -2.86; [-3.73, -2.00]).ConclusionThese analyses from the NESTED study indicate that sleep disruption may be one mechanism through which online instruction impacted learning during the pandemic. Sleep disturbances were unexpectedly influential for unscheduled instruction (i.e., asynchronous). Future analyses will examine specific sleep parameters (e.g., timing) and whether sleep’s influence differs in teens who self-report learning/behavior problems (e.g., ADHD). These nationwide data further underscore the importance of considering sleep as educators and policy makers determine school schedules.Support (if any):

Multidimensional Sleep Health and Physical Functioning in Older Adults

Prior studies link specific sleep parameters to physical functioning in older adults. Recent work suggests the utility of examining sleep health from a multidimensional perspective, enabling consideration of an individual’s experience across multiple different sleep parameters (e.g., quality, duration, timing). We examined the associations of multidimensional sleep health with objective, performance-based measures of physical functioning in older adults. We conducted a secondary analysis of 158 adults (Mage=71.8 years; 51.9% female) who participated in the Midlife in the United States (MIDUS) 2 and MIDUS Refresher studies. We used data from daily diaries, wrist actigraphy, and self-report measures to derive a composite multidimensional sleep health score ranging from 0-6, with higher scores indicating better sleep health. Physical function was assessed using gait speed during a 50-foot timed walk, lower extremity strength as measured by a chair stand test, and grip strength assessed with dynamometers. We used hierarchical regression to examine the associations between sleep health and gait speed, lower extremity strength, and grip strength. Age, sex, race, education, depression symptoms, medical comorbidity, and body mass index were covariates in each model. In adjusted analyses, better multidimensional sleep health was significantly associated with faster gait speed (B=.03, p=.01). Multidimensional sleep health was not significantly associated with lower limb strength (B=-.12, p=.89) or grip strength (B=.45, p=.40). Gait speed is a key indicator of functional capacity as well as morbidity and mortality in older adults. Multidimensional sleep health may be a therapeutic target for improving physical functioning and health in older adults.

Disruption of NREM sleep and sleep-related spatial memory consolidation in mice lacking adult hippocampal neurogenesis

Cellular plasticity at the structural level and sleep at the behavioural level are both essential for memory formation. The link between the two is not well understood. A functional connection between adult neurogenesis and hippocampus-dependent memory consolidation during NREM sleep has been hypothesized but not experimentally shown. Here, we present evidence that during a three-day learning session in the Morris water maze task a genetic knockout model of adult neurogenesis (Cyclin D2−/−) showed changes in sleep macro- and microstructure. Sleep EEG analyses revealed a lower total sleep time and NREM fraction in Cyclin D2−/− mice as well as an impairment of sleep specific neuronal oscillations that are associated with memory consolidation. Better performance in the memory task was associated with specific sleep parameters in wild-type, but not in Cyclin D2−/− mice. In wild-type animals the number of proliferating cells correlated with the amount of NREM sleep. The lack of adult neurogenesis led to changes in sleep architecture and oscillations that represent the dialog between hippocampus and neocortex during sleep. We suggest that adult neurogenesis—as a key event of hippocampal plasticity—might play an important role for sleep-dependent memory consolidation and modulates learning-induced changes of sleep macro- and microstructure.

More than a quarter century of the most prescribed sleeping pill: Systematic review of zolpidem use by older adults

Zolpidem is widely used to treat insomnia of older adults despite that few randomized controlled studies were conducted in this group. We systematically reviewed the relevant literature on efficacy/effectiveness and safety of zolpidem use by elderly individuals in relevant databases completed with a manual search of key journals. Studies were required to include individuals aged ≥60years under intervention with zolpidem compared to placebo or other hypnosedatives. Outcomes were either objectively- or subjectively-assessed improvements in specific sleep parameters and safety for clinical use. The 31 reports selected for review were mostly of low-quality. The evidence suggests that zolpidem is useful typically by reducing sleep latency and episodes of wake after sleep onset, and increasing total sleep time and sleep efficiency. Regarding safety and tolerability, analyses suggest a low risk of daytime sleepiness and of deleterious effects on memory or psychomotor performance, provided that recommended dosage and precautions are followed. Few retrospective studies associate zolpidem use with risk of falls, fractures, dementia, cancer, and stroke. Zolpidem appears effective at lower doses and for short-term treatment among the elderly. Rigorous, new clinical trials are warranted to further document the specific effects of zolpidem in older individuals.

EVALUATING THE ASSOCIATION BETWEEN SLEEP AND MEMORY IN OLDER VETERANS WITH PTSD

Sleep disturbances are core symptoms of posttraumatic stress disorder (PTSD), and recent studies also suggest a link between PTSD and cognitive impairment. There is some evidence of an association between sleep disturbances and cognitive abilities, such as memory, though few studies have focused on older adults and fewer still among those with mental health conditions. This study examined the association between subjective memory complaints and sleep (quality and quantity) in older veterans with PTSD. Fifty-four veterans with PTSD (M age=67.4, 85.2% African American, 90.7% men) participated in the study. Sleep was assessed using the Pittsburgh Sleep Quality Inventory (PSQI) and the PSQI Addendum for PTSD (PSQI-A). Memory was assessed using the Frequency of Forgetting Scale (FOF) derived from the Memory Functioning Questionnaire. The relationship between sleep quality parameters and FOF were examined using bivariate correlations and independent samples t test. Over 60% of participants met military-specific criteria for poor sleep (PSQI≥10; PSQI-A>5). Overall sleep quality on the PSQI-A was significantly associated with worse memory (r=-0.38, p<.01). Among specific sleep parameters (e.g., sleep latency, sleep duration), greater daytime dysfunction due to sleepiness was significantly associated with worse memory (r=-0.44, p<.01). Between-group analyses comparing memory complaints across participants classified as ‘poor’ versus ‘good’ sleepers on the PSQI-A approached significance (t(52)=1.93, p=.06). This study suggests that poor sleep may be a correlate of memory complaints among older adults with PTSD. Future studies are needed to determine whether poor sleep is an underlying factor in the link between PTSD and cognitive impairment.

Insomnia-related interpretational bias is associated with pre-sleep worry.

Cognitive models of insomnia highlight the role of biased cognition in sleep-related information, which is proposed to underlie pre-sleep worry, which in turn results in both subjective and objective sleep deficits. To test this hypothesis, the current study investigated interpretational bias, which is a tendency to interpret ambiguous stimuli in a threat-related (here: insomnia-related) manner. We specifically hypothesized that interpretational bias would be associated with (a) pre-sleep worry and (b) poor subjective and objective sleep. Interpretational bias was measured using the ambiguous scenario task, in which participants (n=76, community sample) were presented with two types of scenarios (insomnia and anxiety related) that could be alternatively interpreted in a neutral manner. Participants additionally completed questionnaires to assess global sleep quality and pre-sleep worry, which were followed by 1-week sleep assessments (via diaries and actigraphy) to estimate specific, daily subjective and objective sleep parameters. The results showed that insomnia-related (but not anxiety-related) interpretational bias was positively associated with pre-sleep worry as well as overall sleep quality. However, these associations could be explained by general trait anxiety. We also found no connection to specific subjective or objective parameters of daily sleep, such as sleep onset latency. These findings support the cognitive-hyperarousal mechanism, where biased cognition (together with trait anxiety) underlies pre-sleep worry. The association with overall sleep quality, but not with specific, daily subjective or objective sleep parameters, may suggest that interpretational bias is specifically relevant for how individuals judge and describe their sleep quality.

Intraindividual sleep variability and its association with insomnia identity and poor sleep

ObjectiveInsomnia identity refers to the conviction that one has insomnia, which can occur independently of poor sleep. Night-to-night variability in sleep (termed intraindividual variability [IIV]) may contribute to insomnia identity yet remain undetected via conventional mean analyses. This study compared sleep IIV across four subgroups: noncomplaining good sleepers (NG), complaining poor sleepers (CP), complaining good sleepers (CG), and noncomplaining poor sleepers (NP). MethodsThis study analyzed 14 days of sleep diary data from 723 adults. Participants were classified according to presence/absence of a sleep complaint and presence/absence of poor sleep. A 2 × 2 multivariate analysis of covariance (MANCOVA) was performed to explore differences on five measures of sleep IIV: intraindividual standard deviation in total sleep time (iSD TST), sleep onset latency (iSD SOL), wake after sleep onset (iSD WASO), number of nightly awakenings (iSD NWAK), and sleep efficiency (iSD SE). ResultsMANCOVA revealed significant main effects of poor sleep, sleep complaint, and their interaction on sleep IIV. Poor sleepers exhibited greater IIV across all sleep parameters compared to good sleepers. Similarly, individuals with a sleep complaint exhibited greater IIV compared to individuals with no complaint. The interaction revealed that iSD SOL was significantly greater among CP than NP, and iSD NWAK was significantly greater among CG than NG. ConclusionsGreater night-to-night variability in specific sleep parameters was present among complaining versus noncomplaining sleepers in good and poor sleep subgroups. These findings suggest certain aspects of sleep consistency may be salient for treatment-seeking individuals based on their quantitative sleep status.

Sleep Characteristics and Behavioral Problems Among Children of Alcoholics and Controls.

Past research has indicated that both sleep difficulties and a parental history of alcoholism increase the risk of behavioral problems. But it is not known whether sleep difficulties differentially increase the risk of problem behaviors among children of alcoholics (COAs) and controls. We compared multiple measures of sleep and the relationships between sleep and behavioral problems in these 2 groups of children. One hundred and fifteen children aged 8 to 12 (67% COAs; 56% girls; Mage =10.85, SDage =1.51) participated in this study. Data presented here were taken from Time 1 of a larger prospective study designed to understand the relationship between sleep and alcohol use. All participants were naïve to alcohol and other illicit drugs. Participants were asked to wear an actigraph watch on their nondominant wrist for 1week. Parents completed the Pediatric Sleep Questionnaire and the Achenbach Child Behavior Checklist. Parents of COAs were more likely to rate their children as overtired compared with parents of non-COAs. Structural equation modeling analyses focusing on overall internalizing and externalizing problems did not reveal any group differences on the relationships between sleep measures and behavioral problems. Regression analyses focusing on specific behavioral problems showed that longer total sleep time, parental ratings of "sleep more" and "sleep less" than other children interacted with COA status to predict specific behavioral problems. Sleep difficulties and duration appear to be a general risk factor for behavioral problems in both COAs and non-COAs, yet the relationships between specific sleep parameters and behavioral problems appear to be different between the 2 groups.

Pilot Validation of Ambulatory Activity Monitors for Sleep Measurement in Huntington's Disease Gene Carriers.

Sleep disturbance occurs early in Huntington's disease (HD). Consumer- and research-grade activity monitors may enable routine assessment of sleep disturbances in HD. We compared Actiwatch Spectrum Pro, Jawbone UP2 and Fitbit One to the gold standard, polysomnography, in four late presymptomatic and three early HD participants. Compared to polysomnography, all ambulatory monitors overestimated total sleep time by >60 minutes and sleep efficiency by ∼15%. Thus, for assessment of specific sleep parameters in HD, none of the activity monitors are sufficiently accurate to replace polysomnography, although they may be sufficient for estimating overall sleep-wake patterns. Larger sample replication is required.

The Association between Subjective Memory Complaints and Sleep within Older African American Adults.

The purpose of the current study is to examine the association between subjective memory complaints and sleep (quantity and quality) in African American older adults. Participants from the Baltimore Study of Black Aging (BSBA; n = 351; mean age = 71.99) completed a self-report sleep scale, subjective memory complaint scale, global cognitive status measure, and demographic questionnaire. Worse overall sleep quality was significantly associated with subjective reports of difficulty recalling the placement of objects, recalling specific facts from reading materials, and worse memory currently compared to the past. Specific sleep parameters (e.g., longer sleep latency and shorter sleep duration) were associated with negative appraisals of participants' ability to do specific tasks involving memory (e.g., difficulty recalling placement of objects). Participants classified as poor sleepers (Pittsburgh Sleep Quality Index [PSQI] total score > 5) were more likely to report worse memory now compared to the past than participants classified as good sleepers (PSQI total score ≤ 5). Evaluation of sleep may be warranted when older adults, particularly African Americans, communicate concerns regarding their memory. Insufficient sleep may be a useful marker of acute daytime dysfunction and, perhaps, cognitive decline. Given memory problems are the hallmark of dementia, our findings support further evaluation of whether poor sleep can aid in the diagnosis of cognitive impairment.