Improving Memory through Better Sleep in Community-dwelling Older Adults: A Tai Chi Intervention Study.

OBJECTIVES: The relationship between sleep and memory has been well documented. However, it remains unclear whether a mind-body exercise, i.e., Tai Chi exercise, can improve memory performance in older adults by improving their subjective and objective sleep. METHOD: A randomized controlled trial was conducted with participants (M = 67.36, 56-79 years) randomly assigned to Tai Chi and control groups. The primary outcomes were sleep, both subjectively reported and objectively assessed by actigraphy, and memory performance, as well as the mediating role of sleep in memory improvement with Tai Chi practice. RESULTS: Tai Chi exercise led to improvements in subjective sleep, as indicated by ISI (p < 0.001, Cohen's d = 0.62) and daytime dysfunction of the PSQI (p = 0.02, Cohen's d = 0.80), and in actigraphy-assessed sleep onset latency (p < 0.01, Cohen's d = 0.61), as well as improved memory performance on digit span forward (p < 0.001, Cohen's d = 1.20) and visual spatial memory tasks (p < 0.01, Cohen's d = 0.83) compared to the control group. Importantly, Tai Chi practice improved digit span forward memory performance through parallel mediation of both subjective sleep (i.e., daytime dysfunction of the PSQI) and objective sleep (i.e., sleep onset latency; b = 0.29, p < 0.01). DISCUSSION: Our findings uncovered the potential benefits of Tai Chi exercise in relation to both subjective and objective sleep in older adults, in turn, how sleep changes played a role in the link between Tai Chi exercise and memory changes in older adults.

Time-Dependent Effects of Altered Prebedtime Light Exposure in Enclosed Spaces on Sleep Performance Associated with Human States.

Purpose: Exposure to artificial light influences human performance, which is essential for maintaining healthy work and sleep. However, existing research has not explored the intrinsic links between sleep performance and human states over time under prebedtime light exposure interventions (LEIs). Methods: To investigate the time-dependent effects of altered prebedtime light exposure, four LEI groupings (#L1 - #L4) and a Time factor (D8, D9, and D10) were chosen for sleep experiments in enclosed spaces. Forty-eight young adults recruited were available for data analysis. Subjective alertness (SA), negative affect (NA), subjective sleep, and objective sleep were measured via the Karolinska Sleepiness Scale, Positive and Negative Affect Schedule, Next-day Self-assessment Sleep Quality, and joint assessment of wrist actigraphy and sleep diaries, respectively. Statistical analysis was used for the effects of light exposure on the human states (corresponding to the SA and NA) and sleep performance, while the process model helped construct the associations between the two. Results: The statistical effects revealed that the Time had a significant main effect on subjective sleep and changes in prebedtime alertness; the LEI had a significant main effect only on sleep onset latency (SOL). After undergoing altered prebedtime light exposure, the mean SA increased at prebedtime of D9 (p = 0.022) and D10 (p = 0.044); No significant effect on the NA was observed; Mean subjective sleep had a significant increase from D8 to D10. Moreover, five actigraphy-estimated sleep parameters were interrelated. In light of this, a chained pathway relationship was identified. The SOL played a mediating predictor between prebedtime state and objective sleep, which was linked to the awakening state through subjective sleep. Conclusion: Our study suggests that time-dependent effects of altered prebedtime light exposure on sleep performance are associated with human states at prebedtime and awakening, with implications for its prediction of sleep health.

Novel biomarkers derived from the Maintenance of Wakefulness Test as predictors of sleepiness and response to treatment.

The Maintenance of Wakefulness Test (MWT) is a widely accepted objective test used to evaluate daytime somnolence and is commonly used in clinical studies evaluating novel therapeutics for excessive daytime sleepiness. In the latter, sleep onset latency (SOL) is typically the sole MWT endpoint. Here, we explored microsleeps, sleep probability measures derived from automated sleep scoring, and quantitative electroencephalography (qEEG) features as additional MWT biomarkers of daytime sleepiness, using data from a phase 1B trial of the selective orexin receptor 2 agonist danavorexton (TAK-925) in people with narcolepsy type 1 (NT1) or type 2 (NT2). Danavorexton treatment reduced the rate and duration of microsleeps during the MWT in NT1 (days 1 and 7; p ≤ 0.005) and microsleep rate in NT2 (days 1 and 7; p < 0.0001). Use of an EEG-sleep-staging-derived measure to determine the probability of wakefulness for each minute revealed a novel metric to track changes in daytime sleepiness, which were consistent with the θ/α ratio, a known biomarker of drowsiness. The slopes of line-fits to both the log-transformed sleepiness score or log-transformed θ/α ratio correlated well to (inverse) MWT SOL for NT1 (R = 0.93 and R = 0.83, respectively) and NT2 (R = 0.97 and R = 0.84, respectively), suggesting that individuals with narcolepsy have increased sleepiness immediately after lights-off. These analyses demonstrate that novel EEG-based biomarkers can augment SOL as predictors of sleepiness and its response to treatment and provide a novel framework for the analysis of wake EEG in hypersomnia disorders.

Eating habits and sleep quality in individuals with type 1 diabetes on continuous glucose monitoring and insulin pump.

BACKGROUND AND AIMS: Sleep disorders are bidirectionally linked with eating behaviors and glucose metabolism, which could be clinically relevant in type 1 diabetes (T1D). We investigated the relationship between dietary habits and sleep quality in individuals with T1D on insulin pumps and continuous glucose monitoring (CGM). METHODS AND RESULTS: In a cross-sectional study, dietary habits (7-day food diary, EPIC questionnaire) and sleep quality (Pittsburgh Sleep Quality Index questionnaire) were assessed in 59 men and 58 women with T1D, aged 19-79 years, using CGM and insulin pump. Differences in dietary habits and blood glucose after dinner (6 h) between participants differing in sleep quality, sleep duration, and sleep onset latency were evaluated. Bad Sleepers (n = 81) were twice as prevalent as Good Sleepers (n = 36) and had a significantly higher intake of fat than Good Sleepers (dinner: 30.7 ± 10.7 vs. 24.0 ± 10.5 g, p = 0.004). Short sleepers had a significantly higher usual intake (g/1000 kcal) of coffee and tea (90.4 ± 71.7 vs. 62.0 ± 35.6), alcoholic (47.8 ± 51.1 vs. 28.9 ± 31.5) and carbonated beverages (21.8 ± 38.1 vs. 9.3 ± 17.2) (p < 0.05 for all) than Long Sleepers. Long Sleep Onset Latency was associated with a significantly higher fat intake at dinner (41.8 ± 7.4 vs. 38.1 ± 9.1 % total energy, p = 0.029) than Short Sleep Onset Latency. No significant differences in post-dinner blood glucose levels were detected between participants with good or bad sleep quality. CONCLUSION: Sleep disruption is common in T1D and is associated with unhealthy dietary choices, especially at dinner, independently of post-dinner blood glucose control.

The effect of the interaction of sleep onset latency and age on ischemic stroke severity via inflammatory chemokines.

Objective: Prolonged sleep onset latency (PSOL) and age have been linked to ischemic stroke (IS) severity and the production of chemokines and inflammation, both of which contribute to IS development. This study aimed to explore the relationship between chemokines, inflammation, and the interplay between sleep onset latency (SOL) and age in influencing stroke severity. Methods: A cohort of 281 participants with mild to moderate IS was enrolled. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and SOL was recorded. Serum levels of macrophage inflammatory protein-1alpha (MIP-1α), macrophage inflammatory protein-1beta (MIP-1ß), monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were measured. Results: NIHSS scores of middle-aged participants with PSOL were significantly higher than those with normal sleep onset latency (NSOL) (p = 0.046). This difference was also observed when compared to both the elderly with NSOL (p = 0.022), and PSOL (p < 0.001). Among middle-aged adults with PSOL, MIP-1ß exhibited a protective effect on NIHSS scores (ß = -0.01, t = -2.11, p = 0.039, R2 = 0.13). MIP-1α demonstrated a protective effect on NIHSS scores in the elderly with NSOL (ß = -0.03, t = -2.27, p = 0.027, R2 = 0.12). Conclusion: This study reveals a hitherto undocumented association between PSOL and IS severity, along with the potential protective effects of MIP-1ß in mitigating stroke severity, especially among middle-aged patients.

Subjective sleep onset latency is influenced by sleep structure and body heat loss in human subjects.

The present study examined the relationship between subjective sleep onset latency (SOL), sleep structure, changes in skin and body temperature, and subjective evaluation of sleep in healthy young adults to elucidate the pathophysiological mechanisms of insomnia. A total of 28 participants (age 21.54 [0.50] years) with no sleep problems participated in a 1-h polysomnographic recording that obtained objective sleep parameters during the daytime while skin and body temperatures were recorded. The distal-proximal skin temperature gradient (DPG) was calculated. Subjective parameters, such as subjective SOL, sleep time, and restorative sleepiness, were evaluated before and after sleep. Most participants estimated their sleep latency as being longer than their actual SOL (13.7 versus 7.6 min). Objective SOL was significantly correlated with each sleep stage parameter whereas subjective SOL was negatively correlated with Stage N2 sleep duration (Rho = -0.454, p = 0.020), slow-wave activity and delta power (Rho = -0.500, p = 0.011 and Rho = -0.432, p = 0.031, respectively), and ΔDPG (the degree of reduction of heat loss before and after lights-off). Stepwise regression analysis showed that ΔDPG was the strongest predictive factor in explaining the length of subjective SOL. The degree of heat dissipation before and after lights-off contributed most to the sensation of falling asleep in healthy young adults. This finding may be helpful for elucidating the physiological mechanisms of insomnia and its treatment.

Sleep Efficiency and Sleep Onset Latency in One Saskatchewan First Nation.

BACKGROUND: Sleep efficiency and sleep onset latency are two measures that can be used to assess sleep quality. Factors that are related to sleep quality include age, sex, sociodemographic factors, and physical and mental health status. This study examines factors related to sleep efficiency and sleep onset latency in one First Nation in Saskatchewan, Canada. METHODS: A baseline survey of the First Nations Sleep Health project was completed between 2018 and 2019 in collaboration with two Cree First Nations. One-night actigraphy evaluations were completed within one of the two First Nations. Objective actigraphy evaluations included sleep efficiency and sleep onset latency. A total of 167 individuals participated, and of these, 156 observations were available for analysis. Statistical analysis was conducted using logistic and linear regression models. RESULTS: More females (61%) than males participated in the actigraphy study, with the mean age being higher for females (39.6 years) than males (35.0 years). The mean sleep efficiency was 83.38%, and the mean sleep onset latency was 20.74 (SD = 27.25) minutes. Age, chronic pain, ever having high blood pressure, and smoking inside the house were associated with an increased risk of poor sleep efficiency in the multiple logistic regression model. Age, chronic pain, ever having anxiety, heart-related illness, and smoking inside the house were associated with longer sleep onset latency in the multiple linear regression model. CONCLUSIONS: Sleep efficiency and sleep onset latency were associated with physical and environmental factors in this First Nation.

Effects of bathing-induced changes in body temperature on sleep.

BACKGROUND: Passive body heating before sleep is well known to lead to improved sleep. However, the effects of the degree of change in body temperature by bathing on sleep quality are unclear. The present study aimed to clarify the effects on sleep of bathing-induced changes in body temperature. METHODS: Twenty-three healthy males and females in their 20 s to 50 s bathed in their homes 1.5-2 h before bedtime under three bathing conditions: showering only; short bathing in a bathtub; and long bathing in a bathtub. Sublingual and skin temperatures and thermal sensation before and after bathing, sleep indices such as sleep onset latency, time in bed, sleep efficiency, and wake after sleep onset, all of which were evaluated using an actimeter, and subjective evaluations of sleep were compared among conditions. RESULTS: Sublingual temperature just after bathing was significantly higher with long bathing than with other conditions, and the fall in sublingual temperature from after bathing to before sleep was significantly larger with long bathing than with short bathing. Sleep onset latency by actimeter was significantly reduced with long bathing compared to showering. In addition, subjective evaluations of falling asleep and sleep quality were better with long bathing than with showering or short bathing. CONCLUSIONS: In conclusion, bathing conditions that produce a 0.9 °C increase in sublingual temperature appear effective for falling asleep and sleep quality, because core temperature shows a greater drop to before sleep than those producing an increase of about 0.3 °C increase in sublingual temperature.

Development of evening sleep homeostatic pressure in early adolescent boys.

The physiological processes governing sleep regulation show maturational changes during adolescent development. To date, data are available to specify when delays in circadian timing occur; however, no longitudinal data exist to characterize the maturation of the accumulation of sleep pressure across the evening. The aim of this longitudinal study was to test whether this change in evening sleep propensity can be identified during early adolescence. Twenty pre-pubescent boys' (Mage = 10.3, SD = 0.4 years) evening sleep homeostats were assessed using a series of sleep latency tests every hour (7:30 p.m. to 3:30 a.m.) at 6-month intervals across four waves. While results revealed shorter sleep onset latencies with increasing wakefulness (p < .001), this effect was not moderated by study wave (p = .79). Evening sleep propensity thus appears to remain stable in boys during early adolescence. Future studies should expand upon these findings by using larger samples of girls as well as boys across an extended age range during the teenage years.

Does ethnic-racial socialization matter? A within-person analysis of racial discrimination and sleep health among Black and Latinx emerging adults.

OBJECTIVES: Emerging work suggests that racism-related stressors may contribute to adverse sleep health, yet little is known about how culturally relevant resources may influence the relationship between racism-related stressors and adverse sleep health. The aim of this study was to examine associations between weekly reports of racial hassles and young adults' sleep health (i.e., sleep onset latency, total sleep time, sleep quality) and to determine whether various forms of parental ethnic-racial socialization would moderate these associations. METHODS: Participants were 141 college students (Mage = 20.7 years, standard deviation (SD) = 1.22, 70% female) who identified as either Black (n = 88; 62.4%) or Latinx (n = 53; 37.6%). Participants completed an initial 1.5-hour assessment in the laboratory and 4 weekly sleep diary surveys (assessed sleep health and depressive symptoms). RESULTS: Weekly racial hassles are related to greater sleep onset latency, decreased total sleep time, and poorer sleep quality. The promotion of mistrust and cultural socialization significantly moderated associations between weekly racial hassles and sleep onset latency and total sleep time, respectively. CONCLUSIONS: These results provide supportive evidence that parental ethnic-racial socialization practices, a preemptive cultural resource, may be an understudied mechanism in sleep health research. Future research is needed to clarify the role of parental ethnic-racial socialization in promoting sleep health equity among youth and young adults.

Changes in sleep quality and sleep disturbances in the general population from before to during the COVID-19 lockdown: A systematic review and meta-analysis.

Introduction: This systematic review and meta-analysis aims to explore changes in sleep quality and sleep disturbances in the general population from before to during the COVID-19 lockdown. Methods: The protocol was registered in PROSPERO (CRD42021256378) and the PRISMA guidelines were followed. The major databases and gray literature were systematically searched from inception to 28/05/2021 to identify observational studies evaluating sleep changes in the general population during the lockdown with respect to the pre-lockdown period. A random effects meta-analysis was undertaken for studies reporting (a) the means of the Pittsburgh Sleep Quality Index (PSQI) global scores or the means of the sleep onset latency (SOL) times (minutes - min) before and during the lockdown, (b) the percentages of poor sleep quality before and during the lockdown, or (c) the percentages of changes in sleep quality. Subgroup analysis by risk of bias and measurement tool utilized was carried out. A narrative synthesis on sleep efficiency, sleep disturbances, insomnia and sleep medication consumption was also performed. Results: Sixty-three studies were included. A decline in sleep quality, reflected in a pooled increase in the PSQI global scores (standardized mean difference (SMD) = 0.26; 95% CI 0.17-0.34) and in SOL (SMD = 0.38 min; 95% CI 0.30-0.45) were found. The percentage of individuals with poor sleep quality increased during the lockdown (pooled relative risk 1.4; 95% CI 1.24-1.61). Moreover, 57.3% (95% CI 50.01-61.55) of the individuals reported a change in sleep quality; in 37.3% (95% CI 34.27-40.39) of these, it was a worsening. The studies included in the systematic review reported a decrease in sleep efficiency and an increase in sleep disturbances, insomnia, and in sleep medication consumption. Discussion: Timely interventions are warranted in view of the decline in sleep quality and the increase in sleep disturbances uncovered and their potentially negative impact on health. Further research and in particular longitudinal studies using validated instruments examining the long-term impact of the lockdown on sleep variables is needed. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256378, identifier CRD42021256378.

Effects of polyphenol-rich interventions on sleep disorders: A systematic review and meta-analysis.

Epidemiology studies have indicated that polyphenol consumption was more likely to have higher sleep quality, but some results remain controversial. A general overview of polyphenol-rich interventions on sleep disorders still lacks in the existing literature. Eligible randomized controlled trials (RCT's) literature retrieval was performed in six databases. Sleep efficiency, sleep onset latency, total sleep time, and PSQI were included as objective measures to compare the effects of placebo and polyphenols in patients with sleep disorders. Subgroup-analyses were performed based on treatment duration, geographic location, study design, and sample size. The mean differences (MD) with 95% confidence intervals (CI) were adopted for four continuous variable data of outcomes in pooled analysis. This study is registered on PROSPERO, number CRD42021271775. In total, 10 studies of 334 individuals were included. Pooled data demonstrated that administration of polyphenols decreases sleep onset latency (MD, -4.38 min; 95% CI, -6.66 to -2.11; P = 0.0002) and increases total sleep time (MD, 13.14 min; 95% CI, 7.54 to 18.74; P＜0.00001), whereas they have no effect on sleep efficiency (MD, 1.04; 95% CI, -0.32 to 2.41; P = 0.13) and PSQI (MD, -2.17; 95% CI, -5.62 to 1.29; P = 0.22). Subgroup analyses further indicated that treatment duration, study design, and number of participants appeared to be responsible for the largest proportion of accountable heterogeneity. Polyphenols' potential importance is highlighted by these findings in treating sleep disorders. The development of large-scale, randomized, controlled trials is recommended to providing further evidence for therapeutic use of polyphenols in a variety of sleep difficulties.

Association of sleep-related disorders with cardiovascular disease among adults in the United States: A cross-sectional study based on national health and nutrition examination survey 2005-2008.

Background and objective: The association between sleep-related disorders and cardiovascular diseases (CVDs) remains controversial and lacks epidemiological evidence in the general population. We investigated whether sleep-related disorders are related to CVDs in a large, nationally representative, diverse sample of American adults. Materials and methods: Data were collected from the National Health and Nutrition Examination Survey (NHANES) 2005-2008. Logistic regression was performed to explore associations of sleep-related disorders with the prevalence of total and specific CVDs. Stratified subgroup analysis was performed to exclude interactions between variables and sleep-related disorders. Non-linearity was explored using restricted cubic splines. Results: In total, 7,850 participants aged over 20 years were included. After controlling for confounders, multivariate regression analysis showed that sleep problems were associated increases in risk of 75% for CVD (OR: 1.75; 95% CI 1.41, 2.16), 128% for congestive heart failure (CHF) (OR: 2.28; 95% CI 1.69, 3.09), 44% for coronary heart disease (CHD) (OR: 1.44; 95% CI 1.12, 1.85), 96% for angina pectoris (AP) (OR: 1.96; 95% CI 1.40, 2.74), 105% for heart attack (OR: 2.05; 95% CI 1.67, 2.53) and 78% for stroke (OR: 1.78; 95% CI 1.32, 2.40). Daytime sleepiness was associated increases in risk of 54% for CVD (OR: 1.54; 95% CI 1.25, 1.89), 73% for CHF (OR: 1.73; 95% CI 1.22, 2.46), 53% for AP (OR: 1.53; 95% CI 1.12, 2.10), 51% for heart attack (OR: 1.51; 95% CI 1.18, 1.95), and 60% for stroke (OR: 1.60; 95% CI 1.09, 2.36). Participants with insufficient sleep had a 1.42-fold higher likelihood of CVD (OR: 1.42; 95% CI 1.13, 1.78) and a 1.59-fold higher likelihood of heart attack (OR: 1.59; 95% CI 1.19, 2.13) than participants with adequate sleep. Prolonged sleep-onset latency was associated with an increased risk of CVD (OR: 1.59; 95% CI 1.17, 2.15), CHF (OR: 2.08; 95% CI 1.33, 3.23) and heart attack (OR: 1.76; 95% CI 1.29, 2.41). Short sleep-onset latency was associated with a 36% reduction in stroke risk (OR: 0.64; 95% CI 0.45, 0.90). The association of sleep problems with CVD risk was more pronounced in the group younger than 60 years (p for interaction = 0.019), and the relationship between short sleep-onset latency and total CVD differed by sex (p for interaction = 0.049). Additionally, restricted cubic splines confirmed a linear relationship between sleep-onset latency time and CVD (p for non-linearity = 0.839) and a non-linear relationship between sleep duration and CVD (p for non-linearity <0.001). Conclusion: According to a limited NHANES sample used to examine sleep-related disorders and CVD, total and specific CVDs could be associated with certain sleep-related disorders. Additionally, our study uniquely indicates that CVD risk should be considered in participants younger than 60 years with sleep problems, and shortened sleep-onset latency may be a CVD protective factor in females.

Novel temperature-controlled sleep system to improve sleep: a proof-of-concept study.

The sleep-wake cycle is regulated by circadian Process C and homeostatic Process S. Selective thermal stimulation (STS) of the cervical spine region enhances glabrous skin blood flow (GSBF) and augments body heat dissipation to increase distal-to-proximal skin gradient (DPG) causing decrease of core body temperature (CBT), which can shorten sleep onset latency (SOL) and improve sleep quality. A total of 11 young healthy/normal sleeper males challenged to go to bed (lights-off) 2 h earlier than usual were subjected in a randomised order to non-consecutive treatment and control night-time sleep sessions. The treatment night entailed activation of a dual-temperature zone mattress with a cooler centre and warmer periphery plus STS pillow that applied mild heating to the cervical spinal skin for 30 min after lights-off for sleep. During the first 30 min after lights-off, GSBF (mean [standard error (SE)] Δ = 49.77 [19.13] perfusion units, p = 0.013) and DPG (mean [SE] Δ = 2.05 [0.62] °C, p = 0.005) were significantly higher and CBT (mean [SE] Δ = -0.15 [0.07] °C, p = 0.029) was significantly lower in the treatment than control night, while there was no significant difference in these variables during the 45 min prior to lights-off (baseline). Moreover, SOL was significantly reduced (mean [SE] Δ = -48.6 [23.4] min, p = 0.032) and subjective sleep quality significantly better (p < 0.001) in the treatment than control night. In conclusion, the novel sleep facilitating system comprised of the STS pillow plus dual-temperature zone mattress induced earlier increase in GSBF and DPG and earlier decline in CBT. This resulted in statistically significant shortened SOL and improved overall sleep quality, thereby reducing sleep pressure of Process S, even under the challenging investigative protocol requiring participants to go to sleep 2 h earlier than customary.

Insomnia in the Older Adult.

Although insomnia is not a normal part of the aging process, its prevalence increases with age. Factors such as medications and medical and psychiatric disorders can increase the risk for insomnia. In order to diagnose insomnia, it is important for older adults to complete comprehensive sleep and health histories. Cognitive behavioral therapy for insomnia, which includes stimulus control, sleep restriction, sleep hygiene, and cognitive therapy, is the recommended first-line treatment of insomnia and is more effective that medications for the long-term management of insomnia. Medications such as benzodiazepines and antidepressants should be avoided for the treatment of insomnia in older adults.

Exploring the relationship of sleep, cognition, and cortisol in sickle cell disease.

Background: Neurocognitive impairment is common in people with Sickle Cell Disease (SCD) and evidence is accumulating that sleep disturbances play a role. The interaction between cortisol and sleep in the general population is associated with cognition as well as general wellbeing but there are few data in SCD. We aimed to understand the relationship between cortisol and sleep in individuals with SCD and explored associations with cognition. Methods: Forty-five participants of black heritage (SCD: N = 27, 9-29 years, 16 females; Controls: N = 18, 11-25 years, 13 females) were recruited from the community between 2018 - 2020. Participants completed standardized questionnaires about their sleep behaviour and wore actigraphy MotionWatch8 for 7 nights to assess nocturnal sleep patterns. Salivary cortisol samples were taken on wakening and 3 times after 14:00. Cognition was assessed using the Wechsler Intelligence Scales for children and adults. Results: People with SCD took longer to fall asleep and experienced greater wake bouts, mobile minutes and fragmented sleep compared to controls. Although non-significant, people with SCD experienced lower morning cortisol, with a flattened diurnal cortisol ratio compared to controls. Interestingly, SCD participants, but not controls, with low diurnal variation scored lowest on processing speed (PSI) and perceptual reasoning index (PRI). A moderator analysis revealed that the effect of morning cortisol and diurnal cortisol ratio on PRI by group health (i.e., SCD and healthy controls) depended on sleep quality. Discussion: Sleep and cortisol may play a crucial role in the expression of cognitive difficulties seen in SCD. This should be considered for the development of interventions to optimise cognitive functioning and sleep. This, in turn, could positively impact on secretion of cortisol and general health in SCD.

Short-term and long-term associations with sleep onset latency in school children in Japan.

BACKGROUND: This study aims to examine the relationships between sleep onset latency and multiple sleep-related factors of seventh and tenth graders during the transition from childhood to adolescence. METHODS: Regarding sleep onset latency, we examined the short-term associations in Phase IV (2002) and long-term associations in Phase V (2005) of the Toyama Birth Cohort Study. In total, 4,673 boys and 4,694 girls in Phase IV and 2,969 boys and 3,108 girls in Phase V answered the questionnaire items regarding sleep, physical and mental health, lifestyle, socioeconomic status, and family and school factors. Considering sleep onset latency as the outcome and 13 sleep-related factors as independent variables, we calculated the odds ratio using binary logistic regression. The longitudinal study was conducted with 1,703 boys and 1,919 girls whose sleep onset latency was within 30 min in Phase IV. RESULTS: The following factors were found to be related to longer sleep onset latency in the short term: sleep duration, physical activity, game time, and self-esteem in boys and sleep duration, bedroom environment, game time, abdominal pain, long-standing illness, onset of puberty, mental health difficulties, and school avoidance feelings in girls. Regarding its long-term effects, having a single parent and self-esteem in boys and breakfast, game time, long-standing illness, obesity, onset of puberty, and school avoidance feelings in girls were associated with longer sleep onset latency. CONCLUSIONS: Education of adolescent health and sleep hygiene at home and school should include both short-term and long-term associations between sleep and a healthy lifestyle by gender.

Sleep Quality Reports From Family Caregivers and Matched Non-caregiving Controls in a Population-Based Study.

The stress of family caregiving may affect many health-related variables, including sleep. We evaluated differences in self-reported sleep quality between incident caregivers and matched non-caregiving controls from a national population-based study. Caregivers and controls were identified in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study and matched on seven different demographic and health history factors. Caregivers reported significantly longer sleep onset latency than controls, before and after adjusting for covariates (ps < .05). No differences were found on measures of total sleep time or sleep efficiency. Among caregivers only, employed persons reported less total sleep time and number of care hours was a significant predictor of total sleep time. Dementia caregivers did not differ from other caregivers. This is one of the few population-based studies of sleep quality in family caregivers. Additional research is needed to examine whether sleep disturbance contributes to greater health problems among caregivers.

Sleep Self-Report and Actigraphy Measures in Healthy Midlife Women: Validity of the Pittsburgh Sleep Quality Index.

Background: Validity of the Pittsburgh Sleep Quality Index (PSQI) has not been established for midlife women before menopause, and evidence suggests that two-factor or three-factor models may be more informative than the PSQI global score derived from its seven components. We hypothesized that the PSQI and its factor structure would be valid in premenopausal women. Materials and Methods: We performed a validation study of the PSQI against wrist actigraphy in a community-based convenience sample of 71 healthy premenopausal women (aged 40-50 years). For convergent validity, PSQI and its component scores were compared with homologous actigraphy measures. For discriminant validity, characteristics known to affect sleep quality were compared, including body mass index, exercise, menopausal status, menopausal symptoms, and depressive symptoms measured with the Center for Epidemiological Studies-Depression (CES-D) Scale. Results: The PSQI global score and Components 1 (quality) and 5 (disturbance) were correlated (p < 0.05) with actigraphy-measured wake after sleep onset. The PSQI global score and Components 1 (quality) and 7 (daytime dysfunction) were correlated with CES-D scores. PSQI Components 2 (onset latency) and 4 (efficiency) were not congruent with homologous actigraphy measures, while component 3 (duration) was congruent with actigraphy duration. The single-factor PSQI global score had a higher McDonald's omega (0.705) and Cronbach's alpha (0.702) than the two-factor or three-factor models. Conclusions: The PSQI global score is a valid measure of sleep quality in healthy midlife women, performing better than two-factor or three-factor models. However, overlapping CES-D and PSQI scores warrant further clinical assessment and research to better differentiate poor sleep quality from depression.

Effect of early intervention for anxiety on sleep outcomes in adolescents: a randomized trial.

The potential effect of early intervention for anxiety on sleep outcomes was examined in a sample of adolescents with anxiety (N = 313, mean 14.0 years, SD = 0.84, 84% girls, 95.7% Norwegians). Participants were randomized to one of three conditions: a brief or a standard-length cognitive-behavioral group-intervention (GCBT), or a waitlist control-group (WL). Interventions were delivered at schools, during school hours. Adolescents with elevated anxiety were recruited by school health services. Questionnaires on self-reported anxiety symptoms, depressive symptoms, and sleep characteristics were administered at pre- and post-intervention, post-waitlist, and at 1-year follow-up. Adolescents reported reduced insomnia (odds ratio (OR) = 0.42, p < 0.001) and shorter sleep onset latency (d = 0.27, p <  0.001) from pre- to post-intervention. For insomnia, this effect was maintained at 1-year follow-up (OR = 0.54, p = 0.020). However, no effect of GCBT on sleep outcomes was found when comparing GCBT and WL. Also, no difference was found in sleep outcomes between brief and standard-length interventions. Adolescents defined as responders (i.e., having improved much or very much on anxiety after GCBT), did not differ from non-responders regarding sleep outcomes. Thus, anxiety-focused CBT, delivered in groups, showed no effect on sleep outcomes. Strategies specifically targeting sleep problems in adolescents should be included in GCBT when delivered as early intervention for adolescents with elevated anxiety.Trial registry Clinical trial registration: School Based Low-intensity Cognitive Behavioral Intervention for Anxious Youth (LIST); http://clinicalrials.gov/ ; NCT02279251, Date: 11.31. 2014.