Objective assessment of fatigue among aviation personnel using a bio-mathematical model: An experimental study.

Background: There are many subjective and objective tools to detect, assess, and quantify fatigue. This study is a novice attempt to assess the occupational fatigue among the aviation personnel employing a computerized work-rest schedule tool integrated with actigraphy. Methods: Thirty-eight aviation personnel were assessed for their sleep by using an actigraphy device. A work-rest scheduling software program called Fatigue Avoidance Scheduling Tool (FAST) was used to obtain fatigue parameters like Fatigue Risk Time (FRT), Fatigue Free Time (FFT), and Fatigue Free Occupational Time (FFOT). Results: The percentages of crew having a night sleep of the duration of more than 6 hours were 50% (Mon), 44.7% (Tue), 44.7% (Wed), and 47.3% (Thu) for weekdays and 65.8% (Fri), 57.9% (Sat), and 57.9% (Sun) for the weekend. There was a gradual increase in FRT, FFT, and FFOT from Day 1 to Day 5 of the week, and the differences were statistically significant. Conclusion: Increase in the FRT with a reciprocal drop of FFT and FFOT was observed with the progress of the week. Total Sleep Time (TST) of less than 8 hours could be the reason for a gradual increase in sleep debt, leading to fatigue depicted as increase in fatigue risk parameter FRT and gradual decrease in fatigue preventing parameters like FFT and FFOT. It was further confirmed by regression analysis in which TST was found to be a statistically significant predictor for all fatigue parameters. Regression equation for FFOT as 498.53 + (0.39 x TST) - (58.8 x Day of the week) can be used.

Hormone physiology and sleep dynamics among BaYaka foragers of the Congo Basin: Gendered associations between nighttime activity, testosterone, and cortisol.

Sleep quality is an important contributor to health disparities and affects the physiological function of the immune and endocrine systems, shaping how resources are allocated to life history demands. Past work in industrial and post-industrial societies has shown that lower total sleep time (TST) or more disrupted nighttime sleep are linked to flatter diurnal slopes for cortisol and lower testosterone production. There has been little focus on these physiological links in other socio-ecological settings where routine sleep conditions and nighttime activity demands differ. We collected salivary hormone (testosterone, cortisol) and actigraphy-based sleep data from Congolese BaYaka foragers (N = 39), who have relatively short and fragmented nighttime sleep, on average, in part due to their typical social sleep conditions and nighttime activity. The hormone and sleep data collections were separated by an average of 11.23 days (testosterone) and 2.84 days (cortisol). We found gendered links between nighttime activity and adults' hormone profiles. Contrary to past findings in Euro-American contexts, BaYaka men who were more active at night, on average, had higher evening testosterone than those with lower nighttime activity, with a relatively flat slope relating nighttime activity and evening testosterone in women. Women had steeper diurnal cortisol curves with less disrupted sleep. Men had steeper cortisol diurnal curves if they were more active at night. BaYaka men often hunt and socialize when active at night, which may help explain these patterns. Overall, our findings indicate that the nature of nighttime activities, including their possible social and subsistence contexts, are potentially important modifiers of sleep quality-physiology links, meriting further research across contexts.

The impact of break duration, time of break onset, and prior shift duration on the amount of sleep between shifts in heavy vehicle drivers.

This study aimed to examine the impact of break duration between consecutive shifts, time of break onset, and prior shift duration on total sleep time (TST) between shifts in heavy vehicle drivers (HVDs), and to assess the interaction between break duration and time of break onset. The sleep (actigraphy and sleep diaries) and work shifts (work diaries) of 27 HVDs were monitored during their usual work schedule for up to 9 weeks. Differences in TST between consecutive shifts and days off were assessed. Linear mixed models (followed by pairwise comparisons) assessed whether break duration, prior shift duration, time of break onset, and the interaction between break duration and break onset were related to TST between shifts. Investigators found TST between consecutive shifts (mean [SD] 6.38 [1.38] h) was significantly less than on days off (mean [SD] 7.63 [1.93] h; p < 0.001). Breaks starting between 12:01 and 8:00 a.m. led to shorter sleep (p < 0.05) compared to breaks starting between 4:01 and 8:00 p.m. Break durations up to 7, 9, and 11 h (Australian and European minimum break durations) resulted in a mean (SD) of 4.76 (1.06), 5.66 (0.77), and 6.41 (1.06) h of sleep, respectively. The impact of shift duration prior to the break and the interaction between break duration and time of break were not significant. HVDs' sleep between workdays is influenced independently by break duration and time of break onset. This naturalistic study provides evidence that current break regulations prevent sufficient sleep duration in this industry. Work regulations should evaluate appropriate break durations and break onset times to allow longer sleep opportunities for HVDs.

How many hours do you sleep? A comparison of subjective and objective sleep duration measures in a sample of insomnia patients and good sleepers.

Our objective was to assess the agreement and linear relationships amongst multiple measures of sleep duration in a sample of patients with insomnia disorder and good sleeper controls. We retrospectively analysed data from 123 patients with insomnia disorder and 123 age- and gender-matched good sleeper controls who completed a simple subjective habitual sleep duration question (Pittsburgh Sleep Quality Index), a sleep diary (5-14 days), 2 nights of polysomnography, and two corresponding morning subjective estimates of sleep duration. Descriptive statistics, linear regression analyses and Bland-Altman plots were used to describe the relationship and (dis)agreement between sleep duration measures. Relationships between polysomnography and the simple question as well as between polysomnography and sleep diary were weak to non-existent. Subjective measures and polysomnography did not agree. Sleep duration measured with the Pittsburgh Sleep Quality Index or sleep diary was about 2 hr above or up to 4 hr below polysomnography-measured sleep duration. Patients with insomnia disorder, on average, reported shorter sleep duration compared with polysomnography, while good sleeper controls, on average, reported longer sleep duration compared with polysomnography. The results suggest that subjective and objective measures apparently capture different aspects of sleep, even when nominally addressing the same value (sleep duration). They disagree in both patients with insomnia disorder and good sleeper controls, but in different directions. Studies assessing sleep duration should take into account both the investigated population and the assessment method when interpreting results. Future studies should continue to investigate possible psychological and physiological correlates of sleep (mis)perception.

Is Cognitive Behavioral Therapy for Insomnia Effective for Improving Sleep Duration in Individuals with Insomnia? A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Accumulating evidence suggests that sleep duration is a critical determinant of physical and mental health. Half of the individuals with chronic insomnia report less than optimal sleep duration. Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment for reducing sleep difficulties in individuals with chronic insomnia. However, its effectiveness for increasing sleep duration is less well-established and a synthesis of these findings is lacking. PURPOSE: To provide a synthesis of findings from randomized controlled trials (RCTs) on the effect of CBT-I on subjective and objective total sleep time (TST). METHODS: A systematic search was performed on articles published from 2004 to 05/30/2021. A total of 43 RCTs were included in the meta-analysis. Publication biases were examined. Meta-regressions were conducted to examine if any sample or treatment characteristics moderated the effect sizes across trials. RESULTS: We found a small average effect of CBT-I on diary-assessed TST at post-treatment, equivalent to an approximately 30-min increase. Age significantly moderated the effects of CBT-I on diary-measured and polysomnography-measured TST; older ages were associated with smaller effect sizes. Contrarily, a negative, medium effect size was found for actigraphy-assessed TST, equivalent to an approximately 30-min decrease. Publication biases were found for diary data at follow-up assessments suggesting that positive findings were favored. CONCLUSIONS: CBT-I resulted in improvements in TST measured by sleep diaries and polysomnography (in adults). These improvements were not corroborated by actigraphy findings. Theoretical and clinical implications were discussed.

Chronic insomnia is a common sleep disorder and can be treated effectively with cognitive behavioral therapy for insomnia (CBT-I). Previous research has consistently shown that CBT-I can reduce sleep difficulties such as difficulty falling and maintaining sleep. The effects of CBT-I on increasing sleep duration are less consistent across studies. This meta-analysis reviewed 43 randomized controlled trials of CBT-I published between 01/01/2004 and 05/30/2021 and synthesized the findings of the effects of CBT-I on sleep duration, measured subjectively and objectively. We found that CBT-I increased sleep duration measured by sleep diaries and polysomnography by about 30 min at post-treatment. This effect is weaker in people with older ages. Contrarily, CBT-I is found to lead to a decrease in sleep duration for about 30 min when sleep duration is measured by actigraphy. The discrepant findings between different sleep measurements reinforce the notion that different measures of sleep assess different aspects of sleep, and that different sleep measurements may have different responsiveness to the treatment of insomnia. Additionally, most people do not achieve the recommended sleep duration at the end of CBT-I. Future studies are needed to evaluate interventions that can help individuals with insomnia increase and maintain optimal sleep duration.

Mind wandering and sleep in daily life: A combined actigraphy and experience sampling study.

Individuals who sleep poorly report spending more time mind wandering during the day. However, past research has relied on self-report measures of sleep or measured mind wandering during laboratory tasks, which prevents generalization to everyday contexts. We used ambulatory assessments to examine the relations between several features of sleep (duration, fragmentation, and disturbances) and mind wandering (task-unrelated, stimulus-independent, and unguided thoughts). Participants wore a wristband device that collected actigraphy and experience-sampling data across 7 days and 8 nights. Contrary to our expectations, task-unrelated and stimulus-independent thoughts were not associated with sleep either within- or between-persons (n = 164). Instead, individual differences in unguided thoughts were associated with sleep disturbances and duration, suggesting that individuals who more often experience unguided train-of-thoughts have greater sleep disturbances and sleep longer. These results highlight the need to consider the context and features of mind wandering when relating it to sleep.

The impact of sleep-wake problems on health-related quality of life among Japanese nursing college students: a cross sectional survey.

AIM: This study was conducted to examine the impact of sleep-wake problems on health-related quality of life of Japanese nursing college students.  METHODS: This cross-sectional study was conducted in 2019 on 150 third and fourth-year nursing college students from two locations in Japan. Insomnia severity was assessed using the Insomnia Severity Index (ISI) and health-related quality of life using the SF-8 questionnaire. The total sleep time (TST) was divided into 3 groups: < 6 h, 6-7 h (reference), and ≥ 7 h. The total ISI score was divided into 2 groups: ≥ 8 points and < 8 points (reference). Logistic regression analysis was performed to evaluate sleep-wake problems related to decline in mental health. RESULTS: The median mental health indicated in the SF-8 questionnaire was divided into two groups, and the factors causing decline in mental health were investigated. The odds ratios (95% confidence interval) for adjusted ISI ≥ 8 and TST on weekdays < 6 h was 6.51 (2.96-14.30) and 3.38 (1.40-8.17), respectively. Mental health status was significantly lower when ISI ≥ 8 and even lower when TST < 6 h. CONCLUSION: Insomnia and short sleep duration are associated with decreased mental health status in nursing college students. Many tended to lack sleep on weekdays. Sleep-wake problems identified while in university should be comprehensively dealt with.

Gender-related sleep duration perception in a Brazilian sleep clinic cohort.

PURPOSE: This study aims to evaluate if gender influences the sleep duration perception in adults referred for polysomnography (PSG). METHODS: A cross-sectional study was undertaken from December 2019 to January 2021. Total sleep time was objectively assessed from the overnight PSG and subjectively estimated. The sleep perception index (SPI) was defined by the ratio of subjective and objective values. Diagnosis of obstructive sleep apnea (OSA) was based on an apnea-hypopnea index ≥ 5.0/h. Insomnia was defined by the presence of one or more specific complaints: difficulty falling asleep, difficulty maintaining sleep, and/or waking up earlier than desired. The association between continuous variables and SPI was assessed by linear regression analysis. RESULTS: This study enrolled 2,004 outpatients (56% men) who were grouped into four subsamples: controls (n = 139), insomnia (n = 154), OSA (n = 912), and insomnia comorbid with OSA [COMISA] (n = 799). In women, the median SPI differed among groups and ranged from 89 to 102% (p = 0.001); while in men, it ranged from 90% to 99% (p = 0.007). However, no gender-related SPI value differences emerged within each of the subgroups: controls (p = 0.907), insomnia (p = 0.830), OSA (p = 0.070), and COMISA (p = 0.547). The presence of insomnia (ß, - 0.101, p < 0.001) or OSA (ß, - 0.082, p = 0.001), but not gender (ß, - 0.017, p = 0.612), were independent predictors of the SPI. CONCLUSION: In a clinical referral cohort, no evidence of sex dimorphism emerged for SPI irrespective of the underlying sleep diagnosis.

Sleep architecture of short sleep time in patients with obstructive sleep apnea: a retrospective single-facility study.

PURPOSE: Sleep architecture consists of rapid eye movement (REM) sleep and non-REM sleep time. Non-REM sleep time is further classified into three stages by depth (stage N1-N3). Some studies have reported that short sleep time predicts all-cause mortality. Short sleep time can have characteristics of sleep architecture which contribute to poor prognosis. Obstructive sleep apnea (OSA) is a disease which causes cessation or decline of ventilation during sleep due to upper airway stenosis and affects sleep architecture. Few studies have reported on the sleep architecture of short sleep time in patients with OSA. Therefore, we aimed to observe this phenomenon. METHODS: From May 2008 to September 2021, patients diagnosed with OSA at our facility were assessed for clinical history and underwent full-night polysomnography (PSG). These patients were classified into two groups: total sleep time (TST) recorded on PSG consisting of a short TST (< 7 h) group and a not short TST (≥ 7 h) group. RESULTS: Of 266 patients with OSA, compared to the not short TST group (n = 131), the short TST group (n = 135) had a lower REM sleep time (%) and a higher stage N1 sleep time (%). There was a significant difference in age between the two groups, so sub-analyses classified the patients by age: non-elderly patients (< 65 years) and elderly patients (≥ 65 years) to adjust for age. Both sub-analyses showed similar results to the analysis for the combined ages regarding sleep architecture. CONCLUSION: Patients with OSA who had short sleep time had disordered sleep architecture with a lower REM sleep time (%) and more stage N1 sleep time.

Sleep arousal burden is associated with long-term all-cause and cardiovascular mortality in 8001 community-dwelling older men and women.

AIMS: To quantify the arousal burden (AB) across large cohort studies and determine its association with long-term cardiovascular (CV) and overall mortality in men and women. METHODS AND RESULTS: We measured the AB on overnight polysomnograms of 2782 men in the Osteoporotic Fractures in Men Study (MrOS) Sleep study, 424 women in the Study of Osteoporotic Fractures (SOF) and 2221 men and 2574 women in the Sleep Heart Health Study (SHHS). During 11.2 ± 2.1 years of follow-up in MrOS, 665 men died, including 236 CV deaths. During 6.4 ± 1.6 years of follow-up in SOF, 105 women died, including 47 CV deaths. During 10.7 ± 3.1 years of follow-up in SHHS, 987 participants died, including 344 CV deaths. In women, multivariable Cox proportional hazard analysis adjusted for common confounders demonstrated that AB is associated with all-cause mortality [SOF: hazard ratio (HR) 1.58 (1.01-2.42), P = 0.038; SHHS-women: HR 1.21 (1.06-1.42), P = 0.012] and CV mortality [SOF: HR 2.17 (1.04-4.50), P = 0.037; SHHS-women: HR 1.60 (1.12-2.28), P = 0.009]. In men, the association between AB and all-cause mortality [MrOS: HR 1.11 (0.94-1.32), P = 0.261; SHHS-men: HR 1.31 (1.06-1.62), P = 0.011] and CV mortality [MrOS: HR 1.35 (1.02-1.79), P = 0.034; SHHS-men: HR 1.24 (0.86-1.79), P = 0.271] was less clear. CONCLUSIONS: Nocturnal AB is associated with long-term CV and all-cause mortality in women and to a lesser extent in men.

Exogenous melatonin as a treatment for secondary sleep disorders: A systematic review and meta-analysis.

Melatonin is a physiological indoleamine involved in circadian rhythm regulation and it is currently used for secondary sleep disorders supported by empirical evidence. A small amount of evidence and some controversial results have been obtained in some randomized controlled trials (RCT). The objective of this meta-analysis is to determine the efficacy of exogenous melatonin versus placebo in managing secondary sleep disorders. Literature retrieval of eligible RCT was performed in 5 databases (PubMed, Embase, Cochrane Library, ClinicalTrials.gov, and Web of Science). In total, 7 studies of 205 patients were included. Pooled data demonstrate that exogenous melatonin lowers sleep onset latency and increases total sleep time, whereas it has little if any effect on sleep efficiency. Although, the efficacy of melatonin still requires further confirmation, this meta-analysis clearly supports the use of melatonin as a management for patients with secondary sleep disorders.

Effect of diurnal fasting on sleep during Ramadan: a systematic review and meta-analysis.

PURPOSE: The current meta-analysis aimed to obtain a more stable estimate of the effect size of Ramadan diurnal intermittent fasting (RDF) on sleep duration and daytime sleepiness. METHODS: Databases (Scopus, ScienceDirect, ProQuest Medical, PubMed/MEDLINE, Web of Science, EBSCOhost, Cochrane, CINAHL, and Google Scholar) were searched from database inception to the end of June 2019. The sleep quality measures analyzed were excessive daytime sleepiness (EDS) measured by the Epworth sleepiness scale (ESS) and total sleep time (TST). Subgroup analyses for age, sex, and levels of physical activity were conducted. RESULTS: We identified 24 studies (involving 646 participants, median age 23.7 years, 73% men) conducted in 12 countries from 2001 to 2019. The results revealed that TST decreased from 7.2 h per night [95% confidence interval (CI) 6.7-7.8] before Ramadan to 6.4 h (95% CI 5.3-7.5) during Ramadan, while the ESS score increased slightly from 6.1 (95% CI 4.5-7.7) before Ramadan to 7.0 (95% CI 5.2-8.8) during Ramadan. Effect sizes on sleep quality measures during RDF demonstrated a moderate reduction in TST (number of studies, K = 22; number of subjects, N = 571, Hedges' g value of -0.43, 95% CI - 0.64 to -0.22, Q = 90, τ2 = 0.15, I2 = 78%, P < 0.001), while ESS score showed negligible effect on EDS (K = 9, N = 362, Hedges' g value of -0.06, 95% CI -0.43 to 0.28, Q = 21, τ2 = 0.13, I2 = 76%, P value = 0.001). CONCLUSION: During the month of Ramadan, there is approximately a 1 hour reduction in TST and nearly a 1 point increase in the ESS score.

Efficacy of SM-1 in a transient insomnia model.

OBJECTIVES: The objectives of this study were primarily to assess the efficacy and safety of SM-1 in a circadian challenge model of transient insomnia and secondarily, to assess the contribution of diphenhydramine to the combination. METHODS: Randomized, double-blind, placebo-controlled three-way cross-over study with a 5-hr phase advance. Subjects were 39 healthy adults reporting a history of transient insomnia. All treatments (SM-1, SM-1 without diphenhydramine, or placebo) were administered to all subjects in a randomly assigned sequence, with at least 1 week between treatments. The primary endpoint was total sleep time (TST) determined by polysomnography. Secondary endpoints included wakefulness after sleep onset (WASO), latency to persistent sleep, number of awakenings (NAW), subjective TST (sTST) and sleep latency (sSL), TST, and NAW by quarters of the night and sleep quality. Safety endpoints included adverse events, Karolinska Sleepiness Scale digit symbol substitution test, and subject-reported alertness level. RESULTS: SM-1 provided an increase of 126.7 min in TST over placebo (p < .001). WASO, sTST, sleep quality, and sSL also showed significant improvement. Diphenhydramine demonstrated a significant (p = .014) contribution of 43.7 min to TST. SM-1 was well-tolerated with type and frequency of adverse events comparable with placebo, and no residual sleepiness upon awakening after 8 hr. CONCLUSIONS: SM-1 provided a robust and statistically significant increase in TST compared with placebo in a circadian model of transient insomnia, without evidence of next-day impairment. Diphenhydramine contributed to the effect.

Sleep Disturbance and Total Sleep Time in Persons Living with HIV: A Cross-Sectional Study.

Short and long sleep durations have been associated with inflammation and chronic diseases. To study the association between sleep duration/quality and HIV disease severity, a cross-sectional study was conducted in patients living with HIV (PLWHs) using self-administered questionnaires assessing total sleep time, insomnia (ICSD-3 criteria), and poor sleep quality (PSQI > 5). Multivariable logistic regression identified the factors associated with sleep disorders and with HIV features. 640 Parisian ambulatory PLWHs were included. The prevalence of insomnia was 50 and 68% of patients had a PSQI > 5. Patients with CD4 count < 500 cells/mm3 were more likely to be long sleepers (> 8 h/day) (OR 1.49; 95% CI [1.10-1.99]: p < 0.01), and less likely to be short sleepers (< 6 h/day) (OR 0.69; 95% CI[0.50-0.96]; p = 0.04) or to experience insomnia (OR 0.59; 95% CI[0.40-0.86]; p < 0.01). HIV features were not associated with a PSQI > 5. Thus, insomnia and impaired sleep quality were highly prevalent in well-controlled PLWHs and the severity of HIV infection was associated with long sleep times.

Longitudinal associations between time spent using technology and sleep duration among adolescents.

Technology use has been the focus of much concern for adolescents' sleep health. However, few studies have investigated the bidirectional association between sleep duration and time spent using technology. The aim of this study was to test whether time spent using technology predicted shorter sleep duration, and/or vice versa using cross-lagged analyses over one year. Participants were 1620 high school students in the 8th and 9th grade at baseline from 17 public schools in three middle Sweden communities. Students completed questionnaires at school during the spring of 2015 and 2016. Time spent using technology was self-reported and sleep duration was calculated from reported bed-times, wake-times and sleep onset latency. Time spent using technology significantly predicted shorter subsequent sleep duration and vice versa. Public health advocates educating others about the negative impacts of technology on sleep must also be mindful of the opposite, that many young people may turn to technological devices when experiencing difficulty sleeping.

Discordant sleep parameters among actigraphy, polysomnography, and perceived sleep in patients with sleep-disordered breathing in comparison with patients with chronic insomnia disorder.

PURPOSE: Although the clinical usefulness of actigraphy (ACT) in chronic insomnia disorder (CID) is extensively investigated, the evaluation on the utility of ACT in sleep-disordered breathing (SDB) is limited and the report of comparison with perceived sleep by patients and polysomnography (PSG) is scarce. METHODS: Thirty-six patients with SDB and 30 with CID underwent PSG and ACT, and they reported perceived sleep time and latency simultaneously. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], sleep efficiency, and wakefulness after sleep onset [WASO]) were compared. Agreement among parameters was assessed with intraclass correlation coefficient (ICC) and 95% confidence interval. RESULTS: ACT overestimated TST and underestimated SOL and WASO relative to PSG in both groups. Perceived sleep was commonly undervalued relative to PSG or ACT. In post hoc analyses, perceived sleep was significantly shorter and SOL significantly longer compared to PSG and ACT in both groups. Perception of sleep time by PSG was significantly higher than perception by ACT. In the CID group, all sleep parameters were significantly correlated between ACT and PSG (ICC = 0.627-0.813). In the SDB group, only TST was significantly correlated (ICC = 0.804). CONCLUSION: ACT is useful to monitor sleep and sleep quality in patients with CID. In patients with SDB, TST by ACT is reliable. However, ACT is insufficient to assess sleep quality due to its low agreement with PSG. Significantly lower sleep perception relative to PSG and ACT should be considered in the treatment of sleep disorders.

How many hours do people sleep in Bangladesh? A country-representative survey.

This study investigated total sleep time in the Bangladeshi population and identified the proportion of the population at greater risk of developing chronic diseases due to inadequate sleep. Using a cross-sectional survey, total sleep time was captured and analysed in 3968 respondents aged between 6 and 106 years in 24 (of 64) districts in Bangladesh. Total sleep time was defined as the hours of total sleep in the previous 24 h. We used National Sleep Foundation (2015) guidelines to determine the recommended sleep hours in different age categories. Less or more than the recommended total sleep time (in hours) was considered 'shorter' and 'longer' sleep time, respectively. Linear and multinomial logistic regression models were used to determine the relationship between demographic variables and estimated risk of shorter and longer total sleep time. The mean (±standard deviation) total sleep time of children (6-13 years), teenagers (14-17 years), young adults and adults (18-64 years) and older adults (≥65 years) were 8.6 (±1.1), 8.1 (±1.0), 7.7 (±0.9) and 7.8 (±1.4) h, respectively, which were significantly different (P < 0.01). More than half of school-age children (55%) slept less than, and 28.2% of older adults slept longer than, recommended. Residents in all divisions (except Chittagong) in Bangladesh were less likely to sleep longer than in the Dhaka division. Rural populations had a 3.96× greater chance of sleeping for a shorter time than urban residents. The Bangladeshi population tends to sleep for longer and/or shorter times than their respective recommended sleep hours, which is detrimental to health.

Effects of lunar phase on sleep in men and women in Surrey.

Recently, evidence has emerged that the phases of the moon may modulate subjective sleep quality and polysomnographically assessed sleep structure in humans. We aimed to explore further the putative effects of circa-lunar periodicity (~29.5 days) on subjective and objective parameters of human sleep in a retrospective analysis. The baseline sleep recordings of 205 (91 males and 114 females; mean age = 47.47 years, standard deviation =19.01; range: 20-84 years) healthy and carefully screened participants who participated in two clinical trials in the Surrey Clinical Research Centre were included in the analyses. Sleep was recorded in windowless sleep laboratories. For each study night, we calculated the distance, in days, to the date of the closest full moon phase and based on this distance, classified sleep records in three lunar classes. Univariate analysis of variance with factors lunar class, age and sex was applied to each of 21 sleep parameters. No significant main effect for the factor lunar class was observed for any of the objective sleep parameters and subjective sleep quality but some significant interactions were observed. The interaction between lunar class and sex was significant for total sleep time, Stage 4 sleep and rapid eye movement (REM) sleep. Separate analyses for men and women indicated that in women total sleep time, Stage 4 sleep and REM sleep were reduced when sleep occurred close to full moon, whereas in men REM duration increased around full moon. These data provide limited evidence for an effect of lunar phase on human sleep.

Patients' estimates of their sleep times: reliability and impact on diagnosis of obstructive sleep apnoea.

BACKGROUND: Home polysomnography (PSG) is an alternative method for diagnosis of obstructive sleep apnoea (OSA). Some types 3 and 4 PSG do not monitor sleep and so rely on patients' estimation of total sleep time (TST). AIM: To compare patients' subjective sleep duration estimation with objective measures in patients who underwent type 2 PSG for probable OSA. METHODS: A prospective clinical audit of 536 consecutive patients of one of the authors between 2006 and 2013. A standard questionnaire was completed by the patients the morning after the home PSG to record the time of lights being turned off and estimated time of sleep onset and offset. PSG was scored based on the guidelines of the American Academy of Sleep Medicine. RESULTS: Median estimated sleep latency (SL) was 20 min compared with 10 min for measured SL (P < 0.0001). There was also a significant difference between the estimated and measured sleep offset time (median difference = -1 min, P = 0.01). Estimated TST was significantly shorter than the measured TST (median difference = -18.5 min, P = 0.002). No factors have been identified to affect patients' accuracy of sleep perception. Only 2% of patients had a change in their diagnosis of OSA based on calculated apnoea-hypopnoea index. CONCLUSIONS: Overall estimated TST in the patients with probable OSA was significantly shorter than measured with significant individual variability. Collectively, inaccurate sleep time estimation had not resulted in significant difference in the diagnosis of OSA.

Efficacy of treatment of insomnia in migraineurs with eszopiclone (Lunesta®) and its effect on total sleep time, headache frequency, and daytime functioning: A randomized, double-blind, placebo-controlled, parallel-group, pilot study.

AIMS: A review on headache and insomnia revealed that insomnia is a risk factor for increased headache frequency and headache intensity in migraineurs. The authors designed a randomized, double blind, placebo-controlled, parallel-group, pilot study in which migraineurs who also had insomnia were enrolled, to test this observation. METHODOLOGY: In the study, the authors treated 79 subjects with IHS-II migraine with and/or without aura and with DSM-IV primary insomnia for 6 weeks with 3 mg eszopiclone (Lunesta(®)) or placebo at bedtime. The treatment was preceded by a 2-week baseline period and followed by a 2-week run-out period. RESULTS: Of the 79 subjects treated, 75 were evaluable, 35 in the eszopiclone group, and 40 in the placebo group. At baseline, the groups were comparable except for sleep latency. Of the three remaining sleep variables, total sleep time, nighttime awakenings, and sleep quality, the number of nighttime awakenings during the 6-week treatment period was significantly lower in the eszopiclone group than in the placebo group (P = 0.03). Of the three daytime variables, alertness, fatigue, and functioning, this was also the case for fatigue (P = 005). The headache variables, frequency, duration, and intensity, did not show a difference from placebo during the 6-week treatment period. CONCLUSIONS: The study did not meet primary endpoint, that is, the difference in total sleep time during the 6-week treatment period between eszopiclone and placebo was less than 40 minutes. Therefore, it failed to answer the question as to whether insomnia is, indeed, a risk factor for increased headache frequency and headache intensity in migraineurs.