Association between personality characteristics and sleep quality among Chinese middle-aged and older adults: evidence from China family panel studies.

BACKGROUND: Poor sleep quality will have adverse effects on physical and mental health, quality of life and other aspects of middle-aged and older adults. Sleep quality is affected by many factors. Whether the sleep quality measures of the participants had changed in the previous or subsequent time period is not easily taken into account. Moreover, there have been no studies on this topic in Chinese middle-aged and older adults. The objective of this study was to mitigate the bias of sleep quality assessment, and analyze the association between personality traits and sleep quality in Chinese middle-aged and older adults. METHODS: The data came from the China Family Panel Studies (CFPS). A total of 6031 participants aged ≥ 45 years were included in this study. Personality characteristics were evaluated based on the scores of each dimension of Big Five personality traits. Sleep duration and sleep perception were used as indicators to measure sleep quality. Logistic models were used to analyze the relationship between personality traits and sleep duration or sleep perception, respectively. RESULTS: 4.5% of the participants had abnormal sleep duration, and 14.4% had a pessimistic sleep perception. Conscientiousness was rated the highest among the personality traits (3.97 ± 0.6). Participants with higher scores for extraversion personality traits had more normal sleep duration (OR = 0.77, 95% CI: 0.64-0.93) and more optimistic sleep perception (OR = 0.86, 95% CI: 0.76-0.96). Using the Internet and feeling unwell in the past week have a moderating effect on the impact of conscientiousness personality characteristics on sleep duration or sleep perception, respectively (but not overall sleep quality). In addition, participants with a spouse or no recent physical discomfort tended to have a normal sleep duration and a more optimistic sleep perception. CONCLUSIONS: The higher the score of extraversion personality traits, the better the overall sleep quality of middle-aged and older adults. Having a spouse and feeling unwell were the important factors affecting their sleep quality. Specific personality traits intervention should be carried out for middle-aged and older adults with poor sleep quality to make their personality traits are closer to extraversion. In addition, middle-aged and older adults without spouses should be encouraged to marry or remarry. We will strengthen health management and medical expenditures for middle-aged and older adults.

Associating night-shift work with lifetime use of sleep medication and sleep quality in a cohort of female nurses.

Night-shift workers often sleep at moments, not in sync with their circadian rhythm. Though the acute effects of night-shift work on sleep quality directly after a night shift are well described, less is known about the chronic effects of night-shift work on sleep. We associated ever-working night shifts and recently working night shifts (<4 wk) with lifetime use of sleep medication and melatonin, self-reported average sleep duration and sleep quality over the 4 wk preceding inclusion (measured using the Medical Outcomes Study Sleep scale). We explored trends in sleep outcomes with average frequency of night shifts per week, tenure of night-shift works in years, and time since last performed night work. This research was conducted within the Nightingale study which is a Dutch cohort study of 59,947 female registered nurses aged 18 to 65. Working night shifts was not associated with self-reported nonoptimal sleep length and sleep quality. However, we observed higher odds of lifetime use of sleep medication for nurses who ever-worked night shifts (OR 1.24; 95% CI 1.13, 1.35) and who recently worked night shifts (OR 1.13; 95% CI 1.05, 1.22); with night-shift work frequency and tenure being associated with lifetime use of sleep medication (P-value for trend < 0.001 for both). Odds for melatonin use were elevated for nurses who ever worked night shifts (OR 1.55; 95% CI 1.40, 1.71) and recently worked night shifts (OR 1.72; 95% CI 1.59, 1,86). The findings of this study have practical implications for healthcare organizations that employ nurses working night shifts. The observed associations between night-shift work and increased lifetime use of prescribed sleep medication and melatonin highlight the need for targeted support and interventions to address the potential long-term sleep problems faced by these nurses.

Clinical phenotypes of obstructive sleep apnea: a cluster analysis based on sleep perception and sleep quality.

PURPOSE: To determine obstructive sleep apnea (OSA) phenotypes using cluster analysis including variables of sleep perception and sleep quality and to further explore factors correlated with poor sleep quality in different clusters. METHODS: This retrospective study included patients with OSA undergoing polysomnography (PSG) between December 2020 and April 2022. Two-step cluster analysis was performed to detect distinct clusters using sleep perception variables including discrepancy in total sleep time (TST), sleep onset latency (SOL), and wakefulness after sleep onset (WASO); objective TST, SOL, and WASO; and sleep quality. One-way analysis of variance or chi-squared tests were used to compare clinical and PSG characteristics between clusters. Binary logistic regression analyses were used to explore factors correlated with poor sleep quality. RESULTS: A total of 1118 patients were included (81.6% men) with mean age ± SD 43.3 ± 13.1 years, Epworth sleepiness score, 5.7 ± 4.4, and insomnia severity index 3.0 ± 2.4. Five distinct OSA clusters were identified: cluster 1 (n = 254), underestimated TST; cluster 2 (n = 158), overestimated TST; cluster 3 (n = 169), overestimated SOL; cluster 4 (n = 155), normal sleep discrepancy and poor sleep quality; and cluster 5 (n = 382), normal sleep discrepancy and good sleep quality. Patients in cluster 2 were older, more commonly had hypertension, and had the lowest apnea-hypopnea index and oxygen desaturation index. Age and sleep efficiency were correlated with poor sleep quality in clusters 1, 2, and 5, and also AHI in cluster 2. CONCLUSION: Subgroups of patients with OSA have different patterns of sleep perception and quality that may help us to further understand the characteristics of sleep perception in OSA and provide clues for personalized treatment.

Judgement of sleep quality of the previous night changes as the day unfolds: A prospective experience sampling study.

How we form judgements of sleep quality is poorly understood. Emerging literature suggests that people infer their sleep quality based on multiple sources of accessible information, raising the possibility that sleep quality judgement may evolve as new relevant information becomes available. This study investigated whether people's rating of sleep quality of the night before changes throughout the following day, and what post-sleep factors are associated with the changes. A prospective experience sampling study of 119 healthy young adults, who completed eight short online surveys interspaced 2 hr apart from 08:00 hours to 22:00 hours. Each survey asked the participants to report total sleep time and sleep quality of the night before, and to provide ratings of current mood, physical and social activity, and pain/discomfort. A memory test was added to the final survey of the day to measure the participants' recall of their first survey responses to sleep quality, as well as total sleep time and mood. The absolute majority (91.1%) of the participants had one or more change in their sleep quality rating across the eight surveys. A similar percentage of change was found for mood rating (100%) but not total sleep time report (20.5%). Memory test in the final survey revealed that the within-person variations in sleep quality rating were not simply memory errors. Instead, positive physical activity post-sleep predicted increases in sleep quality rating. Therefore, judgement of sleep quality of the night before changes as the day unfolds, and post-sleep information can be used by people to infer their sleep quality.

Hypnotizability May Relate to Interoceptive Ability to Accurately Perceive Sleep Depth: An Exploratory Study.

When individuals score high on hypnotizability, they usually report experiencing an altered state of consciousness, physiological changes, and attentional shifts during hypnotic induction procedures as well. We hypothesize that a better interoception of such internal changes is also relevant for accurate sleep perception. We compared subjects scoring high versus low on hypnotizability to the accuracy of their estimations of Sleep Onset Latency (SOL) time awake, and sleep depth and explored their objective sleep. We sampled seven studies performed in our sleep labs across a midday nap or a night resulting in n = 231 subjects (aged 30.11 (SD = 17.02) years, range 18-82 with 15.2% males). Hypnotizability did not influence the accuracy of the perception of time needed to fall asleep or time spent awake. However, the reported sleep depth correlated significantly with the measured amount of slow-wave sleep in high hypnotizables. This pattern appeared across a nap as well as a whole night's sleep studies. We did not find any significant differences in objective sleep patterns depending on hypnotizability. Probably, high hypnotizables benefit from a better interoceptive ability for their perception of their sleep depth.

The underestimation of sleep duration phenotype is associated with better treatment response to cognitive behavior therapy for insomnia in patients with chronic insomnia: a preliminary study.

STUDY OBJECTIVES: To examine treatment response to cognitive behavior therapy for insomnia (CBT-I) in patients with chronic insomnia with and without underestimation of sleep duration. METHODS: We studied 41 patients with chronic insomnia who had received 5-week CBT-I. Self-reported and objective sleep were assessed with sleep diary and actigraphy, respectively. Sleep perception was calculated as self-reported total sleep time/objective total sleep time. The underestimation of sleep duration group was defined based on sleep perception less than the median of the overall sample (85%). Insomnia Severity Index was used to assess the severity of insomnia. RESULTS: The total scores of Insomnia Severity Index decreased significantly after CBT-I in both groups with and without underestimation of sleep duration. Compared to pretreatment, self-reported sleep efficiency increased and total wake time decreased after CBT-I, while the magnitude of changes in sleep efficiency (d = 1.40 vs d=0.81, interaction P = .016) and total wake time (d = -1.82 vs d = -0.85, interaction P < .001) were larger in the underestimation of sleep duration group . Furthermore, self-reported sleep onset latency (interaction P = .520) and wake after sleep onset (interaction P = .052) decreased in the underestimation of sleep duration group (all P < .05), but not in patients without underestimation of sleep duration. Linear regressions showed that lower sleep perception at baseline predicted greater increase in self-reported sleep efficiency (ß = -0.99, P < .001) and total sleep time (ß = -0.51, P = .006) and greater decrease in self-reported total wake time (ß=1.22, P = .023) after CBT-I after adjusting for confounders. CONCLUSIONS: The current preliminary study suggests that sleep perception moderates the self-reported CBT-I effects on chronic insomnia: the phenotype of underestimation of sleep duration is associated with a better response to CBT-I, especially in self-reported sleep parameters. CITATION: Sun Q, Dai Y, Chen B, et al. The underestimation of sleep duration phenotype is associated with better treatment response to cognitive behavior therapy for insomnia in patients with chronic insomnia: a preliminary study. J Clin Sleep Med. 2022;18(10):2443-2450.

The role of beliefs about sleep in nightly perceptions of sleep quality across a depression continuum.

BACKGROUND: Poor sleep quality is common in depression, but complaints of poor sleep quality are not necessarily tied to objective sleep, and the construct of sleep quality remains poorly understood. Previous work suggests that beliefs about sleep may influence sleep quality appraisals, as might sleep variability from night to night. OBJECTIVE: We tested whether beliefs about sleep predict daily sleep quality ratings above and beyond nightly variability of actigraphy and diary-assessed sleep over the course of multiple nights. METHODS: Eighty-eight participants aged 18-65 years across a depressive continuum completed sleep diaries and reported their sleep quality and mood each morning; actigraphy was also completed for 67 of those participants. Multilevel models were used to test previous night's total sleep time and sleep efficiency as predictors of self-reported sleep quality (VAS-SQ) and mood (VAS-M), and whether unhelpful beliefs about sleep predicted VAS-SQ and VAS-M above and beyond the sleep variables. RESULTS: Individuals across a depression continuum with greater unhelpful beliefs about sleep reported worse sleep quality and worse mood upon awakening, even when accounting for nightly variation in actigraphy or diary assessed total sleep time and sleep efficiency. CONCLUSIONS: These results suggest that people are influenced by unhelpful sleep beliefs when making judgements about sleep quality and mood, regardless of how well they slept the previous night. Working with these unhelpful sleep beliefs in cognitive behavioral therapy can thus promote better sleep and mood in people across the depressive continuum.

The effect of "ten needles in the stomach" treatment on sleep perception for the patients with spleen-gastric damp-heat insomnia based on the theory of "stomach upset, sleep restlessness" / 国际中医中药杂志

Objective:To explore the effect of "ten needles in the stomach" on sleep perception of patients with spleen-gastric damp-heat insomnia based on the theory of "stomach discord, then sleep restlessness", to provide references for clinical diagnosis and treatment.Methods:The study subjects were 300 patients with insomnia from the sleep department and outpatient department of Shijiazhuang Traditional Chinese Medicine Hospital. According to the random number method, they were divided into the stomach ten needle group, the diazepam group, and the stomach ten needle plus diazepam group, with 100 in each group. Among them, the stomach ten needles group received "stomach ten needles" acupuncture treatment, the diazepam group was given diazepam therapy, and the stomach ten needles plus diazepam group was given diazepam combined with "stomach ten needles" acupuncture treatment. The Pittsburgh Sleep Quality Index (PSQI) scores, the self-rating disease symptom scale (SCL-90) scores, nighttime polysomnography (PSG) monitoring indicators, and the mean sleep latency (MSL) values were compared before and after treatment in the three groups. The difference in clinical efficacy between the two groups were observed.Results:The total effective rate was 94.0% (94/100) in the combined group, 77.0% (77/100) in the diazepam group, and 85.0% (85/100) in the stomach ten needle group. There were significant differences among the three groups ( χ2=11.56, P<0.01). After treatment, the daytime dysfunction, hypnotic drugs, sleep disturbance, sleep efficiency, sleep time, sleep time, sleep quality score and total score of the combined group were significantly lower than those in the diazepam group and the stomach ten needle group ( F=5.70, 3.65, 5.23, 6.37, 3.66, 6.19, 7.54, 6.40, all Ps<0.01); The scores of SCL-90 and MSL were significantly lower than those in the diazepam group and stomach ten needle group ( F=8.97, 7.53, all Ps<0.01). In the combined group, NWAK [(1.36 ± 0.87) times vs. (2.69 ± 1.15) times, (2.11 ± 1.05) times, F=5.88], SOL [(13.62 ± 5.85) min vs. (25.06 ± 9.42) min, (19.78 ± 7.63) min, F=6.49], N1/TST [(5.69 ± 1.09)% vs. (12.65 ± 2.58)%, (8.49 ± 2.45)%, F=5.13], N2/TST [(51.07 ± 10 2.06)% vs. (58.36 ± 2.18)%, (55.61 ± 2.04)%, F=9.86] were significantly lower than those in the diazepam group and stomach ten needle group ( P<0.01), SE [(90.33 ± 2.89)% vs. (85.39 ± 2.75)%, (87.53 ± 2.69)%, F=8.36], TST [(449.32 ± 23.65) min vs. (421.66 ± 25.33) min, (431.26 ± 25.98) min, F=8.26], REM/TST [(23.87 ± 4.52)% vs. (14.52 ± 3.87)%, (18.36 ± 3.25)%, F=5.34], N3/TST [(18.69 ± 2.02)% vs. (10.31 ± 1.64)%, (14.89 ± 1.74)%, F=7.69] were significantly higher than those in the diazepam group and stomach ten needle group ( P<0.01). Conclusion:Based on the "stomach discord, sleep restlessness" theory, the ten needles on the stomach can treat insomnia and improve psychological state and sleep quality, with the functions of clearing the damp and heat of the middle joker, regulating the lifting and lowering of qi in the middle.

Conscious experiences and high-density EEG patterns predicting subjective sleep depth.

What accounts for feeling deeply asleep? Standard sleep recordings only incompletely reflect subjective aspects of sleep and some individuals with so-called sleep misperception frequently feel awake although sleep recordings indicate clear-cut sleep. To identify the determinants of sleep perception, we performed 787 awakenings in 20 good sleepers and 10 individuals with sleep misperception and interviewed them about their subjective sleep depth while they underwent high-density EEG sleep recordings. Surprisingly, in good sleepers, sleep was subjectively lightest in the first 2 h of non-rapid eye movement (NREM) sleep, generally considered the deepest sleep, and deepest in rapid eye movement (REM) sleep. Compared to good sleepers, sleep misperceptors felt more frequently awake during sleep and reported lighter REM sleep. At the EEG level, spatially widespread high-frequency power was inversely related to subjective sleep depth in NREM sleep in both groups and in REM sleep in misperceptors. Subjective sleep depth positively correlated with dream-like qualities of reports of mental activity. These findings challenge the widely held notion that slow wave sleep best accounts for feeling deeply asleep. Instead, they indicate that subjective sleep depth is inversely related to a neurophysiological process that predominates in early NREM sleep, becomes quiescent in REM sleep, and is reflected in high-frequency EEG activity. In sleep misperceptors, this process is more frequently active, more spatially widespread, and abnormally persists into REM sleep. These findings help identify the neuromodulatory systems involved in subjective sleep depth and are relevant for studies aiming to improve subjective sleep quality.

Appraisals of insomnia identity in a clinical sample.

BACKGROUND: Insomnia identity, the conviction that one has insomnia, occurs independently of sleep quality or quantity, and is associated with numerous negative health outcomes. Little is known about factors influencing insomnia identity. This study planned to evaluate insomnia identity, perceived sleep experience, and sleep parameters. METHOD: Individuals seeking treatment for an insomnia complaint reported demographics, insomnia identity ratings, and daily sleep diaries. Insomnia complaint and insomnia identity were independently crossed with sleep diary data yielding: complaining good (n = 10) and poor sleepers (n = 51), and good (n = 7) and poor sleepers (n = 40) with insomnia identity. Participants were additionally classified as with (n = 50) and without (n = 14) insomnia identity. Group differences and predictors of insomnia identity were assessed. RESULTS: Complaining poor sleepers and poor sleepers with insomnia identity reported significantly poorer sleep ratings compared to their counterparts. Insomnia identity severity was predicted by worse sleep quality comparisons and increased helplessness. Analyses revealed poorer sleep parameters among those with an insomnia identity versus without. DISCUSSION: Group differences may reflect variation in perceived sleep assessment and insomnia identity rating. Results further indicated that not all who complain of insomnia (and seek treatment) endorse insomnia identity. Implications of results and future study directions on insomnia identity are discussed.

Spectral sleep electroencephalographic correlates of sleep efficiency, and discrepancies between actigraphy and self-reported measures, in older men.

Discrepancies between actigraphic and self-reported sleep measures are common. Studies of people with insomnia, in whom both sleep disturbances and discrepancy are common, suggest disturbances and discrepancy reflect differences in the sleeping brain's activity measurable using spectral electroencephalogram (EEG). Disentangling effects of discrepancy and disturbance on sleep EEG could help target research on the consequences and treatments of different sleep phenotypes. We therefore categorized participants in a cohort study including 2,850 men (average age = 76 years, standard deviation = 5.5) into four groups using median splits on actigraphic and self-reported sleep efficiency (SE). We compared spectral power between these groups in 1-Hz bins up to 24 Hz. Compared with the concordant-high SE group: (a) the group with high actigraphic and low self-reported SE had higher spectral power from 11-15 Hz across the night; (b) both groups with low actigraphic SE had higher power across the 15-24 Hz range, predominantly in early cycles, and greater slow frequency power in later cycles. These findings suggest that perceived wakefulness undetected by actigraphy may result from or drive activity corresponding to spindles. We also found, consistent with hyperarousal models, that low SE detectable via actigraphy was related to higher frequency power in the beta range; actigraph-measured inefficiency was also associated with later slow oscillations, potentially representing attempts to dissipate homeostatic drive elevated from earlier hyperarousal. These distinct spectral EEG markers (of low SE measured with actigraphy vs. low perceived SE that is not captured by actigraphy) may have different causes or consequences.

Analysis of Clinical Characteristics and Polysomnography Indicators of Obstructive Sleep Apnea-Hypopnea Syndrome Patients Based on Sleep Perception Types.

Purpose: The aim of this study was to explore the clinical characteristics of different sleep perception types of obstructive sleep apnea-hypopnea syndrome (OSAHS) patients and to analyze the correlation between sleep perception and polysomnography (PSG) indicators in OSAHS patients. Methods: We retrospectively analyzed 355 patients diagnosed with OSAHS by PSG at the Sleep Medicine Center of Shengjing Hospital of China Medical University. Patients saw a doctor due to snoring and daytime sleepiness from March 2017 to March 2018. We excluded the patients who are <18 years old, had a history of OSAHS treatment, had other sleep and psychiatric disorders, and could not provide complete data. According to the patients' explanation, medical history, PSG indicators, and morning questionnaire after PSG, the patients were divided into normal sleep perception (NSP), positive sleep perception abnormality (PSPA), and negative sleep perception abnormality (NSPA). We analyze the demographic characteristics and PSG of the three groups with ANOVA and non-parametric tests. In addition, we conducted correlation analysis between sleep perception and PSG indicators. Results: Of OSAHS patient, 55.5% had sleep perception abnormalities, of which 35.5% were positive-perception abnormalities and 20% were negative-perception abnormalities. From the analysis of PSG indicators, the sleep perception abnormality was related to the frequency of spontaneous arousal of the patient (P = 0.003) and was not related to the slight arousal caused by respiratory events, oxygen desaturations, and limb movement events. OSAHS patients with PSPA had a higher oxygen desaturation index (P = 0.046) but no significant difference in post hoc test. PSPA group had significantly lower rapid eye movement (REM) latency and sleep efficiency and more wake after sleep onset (WASO) than had the other sleep perception groups. Multivariate linear regression analyses after adjusting for age and sex revealed that sleep perception was related to lowest oxygen saturation (LSaO2), TS90%, sleep efficiency, and WASO. Conclusion: Sleep perception abnormality is common in OSAHS patients. OSAHS patients with different sleep perception types have different PSG profiles. The OSAHS patients with PSPA have more severe hypoxia levels at night that require timely personalized treatment.

Exploring the impact of experimental sleep restriction and sleep deprivation on subjectively perceived sleep parameters.

We aimed to investigate the effect of increased sleep pressure and shortened sleep duration on subjective sleep perception in relation to electroencephalographic sleep measures. We analyzed the data from a study in which 14 healthy male volunteers had completed a baseline assessment with 8 hr time in bed, a sleep deprivation (40 hr of wakefulness) and a sleep restriction protocol with 5 hr time in bed during 7 nights. In this work, we assessed perception index, derived through dividing the subjectively perceived total sleep time, wake after sleep onset and sleep latency duration by the objectively measured one at each condition. We found that total sleep time was subjectively underestimated at baseline and shifted towards overestimation during sleep restriction and after deprivation. This change in accuracy of subjective estimates was not associated with any changes in sleep architecture or sleep depth. Wake after sleep onset was significantly underestimated only during sleep restriction. Sleep latency was always overestimated subjectively without any significant change in this misperception across conditions. When comparing accuracy of subjective and actimetry estimates, subjective estimates regarding total sleep time and wake after sleep onset deviated less from electroencephalography derived measures during sleep restriction and after deprivation. We conclude that self-assessments and actimetry data of patients with chronic sleep restriction should be interpreted cautiously. The subjectively decreased perception of wake after sleep onset could lead to overestimated sleep efficiency in such individuals, whereas the underestimation of sleep time and overestimation of wake after sleep onset by actimetry could lead to further underestimated sleep duration.

Sleep Discrepancy in Patients With Comorbid Fibromyalgia and Insomnia: Demographic, Behavioral, and Clinical Correlates.

STUDY OBJECTIVES: Individuals with primary insomnia often have poorer self-reported sleep than objectively measured sleep, a phenomenon termed negative sleep discrepancy. Recent studies suggest that this phenomenon might differ depending on comorbidities. This study examined sleep discrepancy, its night-to-night variability, and its correlates in comorbid insomnia and fibromyalgia. METHODS: Sleep diaries and actigraphy data were obtained from 223 adults with fibromyalgia and insomnia (age = 51.53 [standard deviation = 11.90] years; 93% women) for 14 days. Sleep discrepancy was calculated by subtracting diary from actigraphy estimates of sleep onset latency (SOL-D), wake after sleep onset (WASO-D), and total sleep time (TST-D) for each night. Night-to-night variability in sleep discrepancy was calculated by taking the within-individual standard deviations over 14 days. Participants completed measures of mood, pain, fatigue, sleep/pain medications, nap duration, and caffeine consumption. RESULTS: Average sleep discrepancies across 14 days were small for all sleep parameters (< 10 minutes). There was no consistent positive or negative discrepancy. However, sleep discrepancy for any single night was large, with average absolute discrepancies greater than 30 minutes for all sleep parameters. Greater morning pain was associated with larger previous-night WASO-D, although diary and actigraphy estimates of WASO remained fairly concordant. Taking prescribed pain medications, primarily opioids, was associated with greater night-to-night variability in WASO-D and TST-D. CONCLUSIONS: Unlike patients with primary insomnia, patients with comorbid fibromyalgia do not exhibit consistent negative sleep discrepancy; however, there are both substantial positive and negative discrepancies in all sleep parameters at the daily level. Future research is needed to investigate the clinical significance and implications of high night-to-night variability of sleep discrepancy, and the role of prescribed opioid medications in sleep perception.

Sleep Misperception in Chronic Insomnia Patients with Obstructive Sleep Apnea Syndrome: Implications for Clinical Assessment.

STUDY OBJECTIVES: To investigate whether sleep perception (SP), defined by the ratio of subjective and objective total sleep time, and habitual sleep time in various sleep disorders may be based on comorbid insomnia status. METHODS: We enrolled 420 patients (age 20-79 y) who underwent polysomnography (PSG). They were divided into three groups based on chief complaints: chronic insomnia (CI, n = 69), patients with both obstructive sleep apnea and insomnia (OSA-I, n = 49) or OSA only (OSA, n = 149). Healthy volunteers were also recruited (normal controls [NC], n = 80). We compared differences in PSG parameters and habitual sleep duration and investigated the discrepancy between objective and subjective total sleep time (TST) and sleep latency among four groups. Subjective TST was defined as sleep time perceived by participants the next morning of PSG. RESULTS: SP for TST was highest in the OSA group (median 92.9%), and lowest in the CI group (80.3%). SP of the NC group (91.4%) was higher than the CI, but there was no difference between OSA-I and OSA groups. OSA-I had higher depressive mood compared to the OSA group (p < 0.001). SP was positively associated with the presence of OSA and habitual sleep duration and negatively related to the presence of insomnia and arousal index of PSG. Insomnia patients with (OSA-I) or without OSA (CI) reported the smallest discrepancy between habitual sleep duration and objective TST. CONCLUSIONS: Patients with OSA with or without insomnia have different PSG profiles, which suggests that objective measures of sleep are an important consideration for differentiating subtypes of insomnia and tailoring proper treatment. COMMENTARY: A commentary on this articles appears in this issue on page 1437.

Enhancements to the multiple sleep latency test.

INTRODUCTION: The utility of multiple sleep latency tests (MSLTs) is limited to determining sleep onset latency (SOL) and rapid eye movement sleep latency. The odds ratio product (ORP) is a continuous index of sleep depth with values of 0, 1.0, and 2.5 reflecting very deep sleep, light sleep, and full wakefulness, respectively. We determined the time course of sleep depth during MSLT naps expecting that this would enhance the test's clinical utility. METHODS: Thirty MSLTs (150 naps) were performed for excessive somnolence. Patients indicated whether they slept (yes/no) after each nap. SOL was scored by two experienced technologists. Time course of ORP was determined with a commercial system. We determined ORP at SOL (ORPSOL), times ORP decreased <2.0, <1.5, <1.0 and <0.5 during the entire nap duration, and the integral of decrease in ORP over nap duration (ΔORPINT). RESULTS: SOL occurred almost invariably when ORP was between 1.0 and 2.0. Of 47 naps (21 patients) with SOL <5 minutes, ORP decreased <1.0 (light sleep) in <5 minutes in only 13 naps (nine patients) and <0.5 (deep sleep) in only two naps in one patient. The relation between ORPINT and frequency of sleep perception was well defined, allowing determination of a threshold for sleep perception. This threshold ranged widely (5-50 ΔORP*epoch). CONCLUSION: As currently identified, SOL reflects transition into a highly unstable state between wakefulness and sleep. Reporting the times of attaining different sleep depths may help better identify patients at high risk of vigilance loss. Furthermore, an ORPSOL outside the range 1.0-2.0 can help identify scoring errors.

I sleep with my Mind's eye open: Cognitive arousal and overgeneralization underpin the misperception of sleep.

BACKGROUND AND OBJECTIVES: Misperception of sleep (e.g., underestimation of sleep time relative to objective measures) is a common feature of insomnia and other psychopathologies. To elucidate the mechanisms underlying this tendency, we examined the role of pre-sleep cognitive arousal and overgeneralization. METHODS: We monitored the sleep of 54 community dwellers (the majority being university students), using actigraphy and a sleep diary for 7 days. Immediately after this period, the participants provided an additional global evaluation of their sleep for the past week. In this global evaluation, participants were asked to estimate their average number of hours of sleep and the duration of time taken to fall asleep (sleep onset latency) across the past seven nights. RESULTS: Single-night misperceptions (difference between actigraphy and sleep diary estimations) of sleep time and sleep onset latency were significantly associated with pre-sleep cognitive arousal, but not with overgeneralization. In contrast, global misperception of sleep (difference between sleep diary and global estimations) were associated with overgeneralization, but not with cognitive arousal. LIMITATIONS: Our sample mainly consisted of female university students, which limits the generalizability of the results. CONCLUSIONS: Misperception of sleep occurs in two cases: (1) in the case of a single night due to excessive arousal, and (2) in the case of multiple nights due to overgeneralization.

Sleep Perception in Obstructive Sleep Apnea: A Study Using Polysomnography and the Multiple Sleep Latency Test.

BACKGROUND AND PURPOSE: Discrepancies between objectively measured sleep and subjective sleep perception in patients with insomnia have been reported. However, few studies have investigated sleep-state misperception in patients with obstructive sleep apnea (OSA). We designed this study to 1) delineate the factors that could affect this discrepancy and 2) infer an underlying mechanism in patients with OSA. METHODS: We recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography. RESULTS: Fifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers. CONCLUSIONS: As an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.

Sleep Perception in Obstructive Sleep Apnea: A Study Using Polysomnography and the Multiple Sleep Latency Test

BACKGROUND AND PURPOSE: Discrepancies between objectively measured sleep and subjective sleep perception in patients with insomnia have been reported. However, few studies have investigated sleep-state misperception in patients with obstructive sleep apnea (OSA). We designed this study to 1) delineate the factors that could affect this discrepancy and 2) infer an underlying mechanism in patients with OSA. METHODS: We recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography. RESULTS: Fifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers. CONCLUSIONS: As an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.

Underperception of Naps in Older Adults Referred for a Sleep Assessment: An Insomnia Trait and a Cognitive Problem?

OBJECTIVES: To examine the frequency and determinants of underperception of naps in older adults referred for a sleep assessment. DESIGN: Prospective study. SETTING: Outpatient geriatric sleep clinic. PARTICIPANTS: Individuals aged 60 and older referred for insomnia complaints or suspected sleep apnea (N = 135). MEASUREMENTS: Tests included clinical interview, sleepiness scale, anxiety and depression scale, Insomnia Severity Index (ISI), Mini-Mental State Examination (MMSE), and overnight polysomnography, followed by multiple sleep latency tests. At the end of each of four nap opportunities, participants answered whether they had slept during the test. Nap underperception was defined as two or more unperceived naps. RESULTS: Of the 105 participants who napped at least twice, 42 (40%) did not perceive at least two naps. These participants had lower MMSE scores (P = .01) and were more likely to be taking benzodiazepines (P = .008) than the 63 participants who did not underperceive their naps but had similar demographic characteristics, sleep diagnoses, depression and anxiety scores, and polysomnography measures. Both groups had similarly short mean daytime sleep latencies (9.7 ± 4.5 minutes and 9.8 ± 3.7 minutes), but participants who underperceived their naps scored lower on the Epworth Sleepiness Scale (5.6 ± 4.0, vs 9.6 ± 4.8, P < .001). An ISI of 11 or greater, a MMSE score of 26 or less, and a sleepiness score of 8 or less were each independently associated with underperception of naps. The combination of these three factors yielded a positive predictive value of 93% and a negative predictive value of 71% for nap underperception. CONCLUSION: Older adults referred for sleep consultation with cognitive impairment and greater insomnia symptoms frequently underperceive naps, leading them to underestimate their level of sleepiness. In such cases, objective measures of daytime sleepiness would be better than the Epworth Sleepiness Scale.