Patients with primary insomnia in the sleep laboratory: do they present with typical nights of sleep?

The validity of sleep laboratory investigations in patients with insomnia is important for researchers and clinicians. The objective of this study was to examine the first‐night effect and the reverse first‐night effect in patients with chronic primary insomnia compared with good sleeper controls. A retrospective comparison of a well‐characterised sample of 50 patients with primary insomnia and 50 good sleeper controls was conducted with respect to 2 nights of polysomnography, and subjective sleep parameters in the sleep laboratory and the home setting. When comparing the first and second sleep laboratory night, a significant first‐night effect was observed across both groups in the great majority of the investigated polysomnographic and subjective variables. However, patients with primary insomnia and good sleeper controls did not differ with respect to this effect. Regarding the comparison between the sleep laboratory nights and the home setting, unlike good sleeper controls, patients with primary insomnia reported an increased subjective sleep efficiency on both nights (in part due to a reduced bed time) and an increased subjective total sleep time on the second night. These results suggest that even the second sleep laboratory night does not necessarily provide clinicians and researchers with a representative insight into the sleep perception of patients with primary insomnia. Future studies should investigate whether these findings also hold for other patient populations.     

Do we neglect women with sleep apnea?

Obstructive sleep apnea (OSA) affects approximately 5% of women and 15% of men in the middle-aged adults, and associated with adverse health outcomes. The prevalence and severity of OSA in women increase across the menopause, as the cardiovascular death and events do. Unfortunately, women with OSA might be under-diagnosed due to circumstances related to the family lifestyle and socio-cultural factors in addition to the different OSA clinical expression. Evaluation of cardiovascular global risk assessment in women with OSA is very important to prevent the high potential cardiovascular morbidity and mortality, since they are poorly informed about cardiovascular disease (CVD). So, we should be aware of the clues suspecting OSA and cardiovascular risk in women admitting to sleep clinics.     

Is the SF 36 sensitive to sleep disruption? A study in subjects with sleep apnoea

SUMMARY  The objectives of this study were to test the sensitivity of the short form 36 health survey questionnaire (SF 36) to sleep disruption in patients with obstructive sleep apnoea (OSA) and assess its use as an outcome measure for treatment with nasal continuous positive airway pressure (CPAP). Two hundred and twenty-three subjects under investigation for snoring and/or daytime somnolence completed the questionnaire at presentation and again after a six month period. Subjects with OSA requiring treatment scored lower on all dimensions of the SF 36 ( P <0.05) than normative scores for the general population. The largest differences were for vitality (24%) and social functioning (27.9%). After six months of treatment with CPAP there was an improvement in all scores and the score for vitality was no longer significantly different from that of the general population. The SF 36 is sensitive to the effects of sleep disruption in subjects with obstructive sleep apnoea, is a useful outcome measure for treatment with CPAP and its value in other sleep disorders should be assessed.     

Tiagabine is associated with sustained attention during sleep restriction: evidence for the value of slow-wave sleep enhancement?

STUDY OBJECTIVES: To evaluate the impact of enhanced slow-wave sleep (SWS) on behavioral, psychological, and physiologic changes resulting from sleep restriction DESIGN: A double-blind, parallel-group, placebo-controlled design was used to compare tiagabine, 8 mg, (a SWS-enhancing drug) to placebo during 4 nights of sleep restriction (time in bed = 5 hours per night). Behavioral, psychological, and physiologic measures of the impact of sleep restriction were compared between groups at baseline, during sleep restriction, and following recovery sleep. SETTING: Two sleep research laboratories. PARTICIPANTS: Thirty-eight healthy adults; 9 men and 10 women (mean age: 26.0 +/- 6.1 years) in the placebo group and 8 men and 11 women (mean age: 26.7 +/- 8.1 years) in the tiagabine 8 mg group INTERVENTIONS: Both experimental groups underwent 4 nights of sleep restriction. Each group received either tiagabine 8 mg or placebo on all sleep-restriction nights, and both groups received placebo on baseline and recovery nights. MEASUREMENTS AND RESULTS: Polysomnography documented a SWS-enhancing effect of tiagabine. The placebo group displayed the predicted deficits due to sleep restriction on the Psychomotor Vigilance Task and the Multiple Sleep Latency Test. Compared with placebo, the tiagabine group did not demonstrate impairment in sustained attention on the Psychomotor Vigilance Test, performed better on the Wisconsin Card Sorting Task, reported more restorative sleep, and had less of an increase in afternoon-evening salivary free cortisol. Multiple Sleep Latency Test, ratings of sleepiness, recovery sleep, and other measures did not differ between groups. CONCLUSIONS: To our knowledge these findings are the first to be consistent with the hypothesis that pharmacologic SWS enhancement reduces selective aspects of the behavioral, psychological, and physiologic impact of sleep restriction.     

Is passive smoking associated with sleep disturbance among pregnant women?

STUDY OBJECTIVE: Pregnant women suffer from sleep disturbance, which may be aggravated by passive smoking. In this study we investigated the effects of passive smoking on sleep disturbance during pregnancy. DESIGN: Two cross-sectional questionnaire surveys conducted in 2002 and 2006. SETTING: Clinical institutions specializing in obstetrics and gynecology that participated in the nationwide surveys: 260 in the 2002 survey and 344 in the 2006 survey. PARTICIPANTS: 16,396 and 19,386 pregnant women in Japan surveyed in 2002 and 2006, respectively. INTERVENTION: N/A. MEASUREMENTS AND RESULTS: Pregnant women exposed to passive smoking were likely to have sleep disturbances, such as subjective insufficient sleep, difficulty in initiating sleep, short sleep duration, and snoring loudly/breathing uncomfortably. Smoking pregnant women had the same sleep disturbances and also experienced excessive daytime sleepiness and early morning awakening. The prevalence of 5 types of sleep disturbance (insufficient sleep, difficulty in initiating sleep, short sleep duration, excessive daytime sleepiness, and snoring loudly/breathing uncomfortably) among nonsmokers with environmental tobacco smoke showed a mean value intermediate between that of active smokers and that of nonsmokers without environmental tobacco smoke. CONCLUSION: Passive smoking is independently associated with increased sleep disturbance during pregnancy.     

Is treatment of obstructive sleep apnea syndrome with auto-CPAP useful?

Automatic CPAP therapy has been developed to constantly adapt the positive pressure level to the required needs. The automatic devices have been used in two different ways, one being to determine the pressure level to be prescribed at home for fixed CPAP therapy, and the other one to replace fixed CPAP as an home treatment. This last application should alleviate the need for a titration study. The benefits reported up to now in the literature vary from one machine to another, but usually these machine are effective in abolishing obstructive breathing disturbances and the consecutive sleep fragmentation. The mean positive pressure level applied during automatic CPAP treatment is usually less than the effective pressure level measured during a conventional titration sleep study. Some results suggest that automatic CPAP therapy may improve compliance to CPAP therapy. There is a need to better define if automatic CPAP therapy may benefit to specific groups of sleep apnea patients.     

Does sleep deprivation worsen mild obstructive sleep apnea?

STUDY OBJECTIVES: Sleep deprivation is believed to worsen obstructive sleep apnea (OSA). We assessed the effect of acute sleep deprivation on polysomnography in a cohort of subjects with mild OSA and a cohort of subjects without OSA. DESIGN: Crossover study in which subjects initially had polysomnography after a normal night's sleep or after 36 hours of sleep deprivation, followed by a 2- to 4-week interval, after which subjects were restudied under the alternate testing condition. SETTING AND PARTICIPANTS: 13 subjects with mild OSA and 16 subjects without OSA were studied in a university teaching hospital sleep laboratory. INTERVENTIONS: 36 hours of supervised sleep deprivation. MEASUREMENTS: Subjects' age, body mass index, neck circumference and Epworth Sleepiness Scale scores were measured; actigraphy and sleep diaries were used to estimate prior sleep debt before each sleep study. RESULTS: Sleep deprivation was found to significantly increase total sleep time, sleep efficiency, and rapid eye movement and slow-wave sleep time. Subjects with OSA showed a lower minimum oxygen saturation after sleep deprivation. However, subjects did not show a significantly different respiratory disturbance index, arousal index, or length of the longest apnea after sleep deprivation. CONCLUSIONS: Acute sleep deprivation did not worsen most OSA parameters as measured by polysomnography. A lower minimum oxygen saturation in mild OSA subjects after sleep deprivation may be important in patients with significant cardiorespiratory disease. More research is needed to assess whether daytime performance and function (eg, driving, sleepiness) is more greatly impaired in OSA subjects who are sleep deprived, compared to normal subjects who are sleep deprived.     

The association of sleep with inflammatory bowel disease in children and adolescents

Aim

To systematically review literature investigating sleep quality in children and adolescents with inflammatory bowel disease (IBD).

Methods

Electronic databases were searched (BASE, Cochrane Database of Systematic Reviews, DIMDI, PsychArticles, PsychInfo, Psychjournals, Psychline, PSYNDEX, Pubmed, Science Direct, Web of Science, Wiley Online Library) by two researchers. Eligible studies were all that studied sleep disorders in the context of IBD in children and adolescents (6–17 years of age).

Results

Out of 40 references identified, five studies (all cross-sectional, three of them controlled) were eligible and included in this study. The publications showed that children and adolescents with IBD have significant sleep problems, adding to their impaired quality of life.

Conclusion

The published data provide evidence suggesting an impact of IBD and its severity on sleep in children and adolescents. However, with regard to the low methodological quality, the incongruity of the studies concerning outcome measure, and their focus of exploration, further studies are warranted to highlight the interrelationship.

     

How well do school-aged children comply with imposed sleep schedules at home?

STUDY OBJECTIVES: To quantitatively assess compliance and experimental success with imposed sleep schedules among healthy children involved in an experimental comparison of optimized and restricted sleep. DESIGN: We asked children to follow assigned sleep schedules at home that created optimized (at least 10 hours time-in-bed per night) and restricted (6.5 to 8 hours time-in-bed per night) sleep conditions across 2 weeks during the school year. Self-report or parent-report of bedtime and risetime was obtained daily and continuous actigraphy was recorded. SETTING: Home. PARTICIPANTS: 78 healthy children (41 boys, 37 girls; mean age, 10.2 years; age range, 6.5 to 12.9 years) INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: We used reported time-in-bed to assess noncompliance with assigned schedules. Experimental failure was assessed with actigraphically based estimates of sleep period (time from sleep onset to sleep offset) and total sleep time (minutes of scored sleep during sleep period). Reported time-in-bed averaged 3.45 hours less per night under restricted versus optimized conditions. Sleep period and total sleep time showed similar differences (2.97 and 2.32 hours less, respectively). Four children met a priori criteria for noncompliance (3 for optimized nights and 1 for restricted). Eight children met a priori criteria for experimental failure within conditions (7 for optimized nights and 1 for restricted), but most achieved a substantial difference in sleep behavior across optimized and restricted weeks. CONCLUSIONS: In general, healthy children as young as 6 years of age can maintain substantial changes in their usual schedules across several nights at home and should be considered for inclusion in experimental studies of sleep extension and restriction. This paper offers a methodologic "road-map" for scientists interested in pursuing this goal.     

Is homeostatic sleep regulation under low sleep pressure modified by age?

STUDY OBJECTIVES: We have previously shown that healthy older volunteers react with an attenuated frontal predominance of sleep electroen-cephalogram (EEG) delta activity in response to high sleep pressure. Here, we investigated age-related changes in homeostatic sleep regulation under low sleep pressure conditions, with respect to regional EEG differences and their dynamics. DESIGN: Analysis of the sleep EEG during an 8-hour baseline night, during a 40-hour multiple nap protocol (150 minutes of wakefulness and 75 minutes of sleep) and during the following 8-hour recovery night under constant posture conditions. SETTING: Centre for Chronobiology, Psychiatric University Clinics, Basel, Switzerland PARTICIPANTS: Sixteen young (20-31 years) and 15 older (57-74 years) healthy volunteers INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: All-night EEG spectra revealed an increase in spindle activity (13-15.25 Hz) for both age groups, but only in the young did we find a significant decrease of delta activity (0.5-1.25 Hz) in response to low sleep pressure conditions, predominantly in occipital brain regions. However, delta activity during the first non-rapid eye movement (NREM) sleep episode was equally reduced in both age groups. This response lasted significantly longer in the young (across the first 2 NREM sleep episodes) than in the older participants (only the first NREM sleep episode). CONCLUSION: The initial EEG delta response to low sleep pressure was similar in healthy older and young participants. Therefore, age-related sleep deteriorations cannot solely be attributed to alterations in the homeostatic sleep-regulatory system. It is, rather, the interplay of circadian and homeostatic factors of sleep regulation, which is changed with aging.     

Who is pre‐occupied with sleep? A comparison of attention bias in people with psychophysiological insomnia,delayed sleep phase syndrome and good sleepers using the induced change blindness paradigm

Cognitive models of insomnia suggest that selective attention may be involved in maintaining the disorder. However, direct assessment of selective attention is limited. Using the inducing change blindness (ICB) paradigm we aimed to determine whether there is attentional preference for sleep-related stimuli in psychophysiological insomnia (PI) relative to delayed sleep phase syndrome (DSPS) and good sleepers (GS). In the ICB task, a visual scene, comprising both sleep-related and neutral stimuli, 'flickers' back and forth with one element (sleep or neutral) of the scene changing between presentations. Therefore, a 2 x 3 totally between-participants design was employed. The dependent variable was the number of flickers it took for the participant to identify the change. Ninety individuals (30 per group) were classified using ICSD-R criteria, self-report diaries and wrist actigraphy. As predicted, PI detected a sleep-related change significantly quicker than DSPS and GS, and significantly quicker than a sleep-neutral change. Unexpectedly, DSPS detected a sleep-related change significantly quicker than GS. No other differences were observed between the two controls. These results support the notion that there is an attention bias to sleep stimuli in PI, suggesting that selective attention tasks such as the ICB may be a useful objective index of cognitive arousal in insomnia. The results also suggest that there may be an element of sleep preoccupation associated with DSPS. Results are discussed with reference to other experiments on attentional processing in insomnia.     

Are individuals with paradoxical insomnia more hyperaroused than individuals with psychophysiological insomnia? Event-related potentials measures at the peri-onset of sleep

Preliminary QEEG studies suggest that individuals with paradoxical insomnia (Para-I) display higher cortical arousal than those with psychophysiological insomnia (Psy-I). Lately, finer measures, such as event-related potentials, and especially the N1 and P2 components have been used to document arousal processes in individuals with insomnia. The objective of the present study was to further circumscribe arousal in Psy-I and Para-I using N1, P2 and the waking processing negativity (wPN). N1 and P2 were recorded in the evening, at sleep-onset and in early stage 2 sleep in 26 good sleepers, 26 Psy-I and 26 Para-I. An oddball paradigm was used and participants received the instruction to ignore all stimuli at all times. Three difference waves (wPNs) were computed to evaluate the transition from wakefulness to sleep onset, from sleep onset to sleep and from wakefulness to sleep. Results revealed that N1 was smaller during wakefulness and sleep onset for Psy-I, while it was larger for Para-I during these same times. P2 was smaller at sleep onset for Psy-I than for Para-I and GS, while P2 during wakefulness and stage 2 sleep was larger for Para-I than GS. WPNs revealed that Psy-I showed fewer changes in information processing, while Para-I showed larger changes between recording times. Psy-I appear to present an inability to inhibit information processing during sleep onset, while Para-I seem to present overall enhanced attentional processing that results in a greater need for inhibition.     

Is the nonREM-REM sleep cycle reset by forced awakenings from REM sleep?

In selective REM sleep deprivation (SRSD), the occurrence of stage REM is repeatedly interrupted by short awakenings. Typically, the interventions aggregate in clusters resembling the REM episodes in undisturbed sleep. This salient phenomenon can easily be explained if the nonREM-REM sleep process is continued during the periods of forced wakefulness. However, earlier studies have alternatively suggested that awakenings from sleep might rather discontinue and reset the ultradian process. Theoretically, the two explanations predict a different distribution of REM episode duration.We evaluated 117 SRSD treatment nights recorded from 14 depressive inpatients receiving low dosages of Trimipramine. The alarms were triggered by an automatic mechanism for the detection of REM sleep and had to be canceled by the subjects themselves. The REM episodes were determined as in undisturbed sleep-they had to include the remaining REM activity and were separated by 30 min without REM epochs. The frequency histogram of REM episodes declined exponentially with episode duration for each of the first four sleep cycles. The duration of nonREM intervals revealed bimodal distributions. These results were found consistent with the model assuming a reset of the ultradian cycle upon awakening. Whether REM or nonREM activity is resumed on return to sleep can be modeled by a random decision whereby the probability for REM sleep might depend on the momentary REM pressure.     

Are hot flashes associated with sleep disturbance during midlife? Results from the STRIDE cohort study

Objective

Sleep disturbance and hot flashes are common during menopause, but their association is not well understood. We sought to understand the associations among sleep disturbance and the frequency, bothersomeness, and interference of hot flashes in mid-life women.

Study design

STRIDE is a study of women ages 40–65 years at varied menopausal stages. We examined the cross-sectional associations of sleep disturbance with the frequency and bothersomeness of hot flashes, and interference of hot flashes with work, social, and leisure activities during the 2nd year of STRIDE.

Main outcome measure

Self-reported sleep disturbance.

Results

Of the 623 women with complete data, 370 (59%) reported having hot flashes. Bivariate analyses showed that reporting hot flashes with bother, but not hot flashes alone, was associated with sleep disturbance (odds ratio [OR] [95% confidence interval (CI)]: 2.8 [2.0–4.0] and 1.3 [0.7–2.5], respectively). In multivariable models, women reporting bothersome hot flashes were more likely to report sleep disturbance (OR [95% CI]: 2.1 [1.4–3.2]) compared to women who reported no hot flashes. When the perceived interference of hot flashes with work, social activities, and leisure activities were included in the model, the relationships between bothersome hot flashes and sleep disturbance disappeared.

Conclusions

Hot flashes are not associated with sleep disturbance, unless they are bothersome. Mid-life patients should routinely be queried about the bothersomeness of their hot flashes.     

Laterality of the sleep onset process: Which hemisphere goes to sleep first?

This study aims to assess whether the hemispheric asymmetry inversion observed in the wake-sleep transition can also be revealed by the latency of inter tapping intervals >or= 2.5s for each hand and the latency of theta burst >or= 2.5s in symmetrical loci of the two hemispheres during the sleep onset process. Data collected from 16 right-handed subjects showed a hemispheric asymmetry in the sleep onset latency with both behavioural and EEG indices. For the first time, a hemispheric asymmetry in the sleep onset latency was found considering a visual analysis of EEG. Results suggest that the hemispheric pattern found during sleep onset can be considered a steady characteristic of the transition from wake to sleep, relatively independent of homeostatic and time of night effects. These results are interpreted as being consistent with the hypothesis concerning an advantage of the right hemisphere in sustaining vigilance.     

The relationship between parents’ cognitions,bedtime behaviours and sleep-related practices with their child's sleep

Certain parental cognitions about child sleep and bedtime behaviours used with their child have been linked to poorer child sleep. However, previous research has focused on mothers and explored only a limited range of sleep-related cognitions and practices. The present study investigated whether parental cognitions and sleep-related practices (both in connection with their own sleep and their child's sleep), alongside the bedtime behaviours used with their child were associated with and/or were predictive of their child's sleep. Mothers and fathers from 44 families (with a child aged 12–24 months) separately completed questionnaires reporting (i) their cognitions (about their own sleep and their child's sleep), (ii) sleep-related practices (used in connection with their own and their child's sleep) and (iii) bedtime behaviours used with their child. Child sleep was assessed through parental report and actigraphy. Both parents’ cognitions about their own sleep predicted cognitions about their child's sleep. Mothers’ own sleep-related practices predicted the types of practices they used with their child. Different patterns of maternal and paternal variables influenced parental perceptions of their child having a sleep problem. The present findings highlight the importance of including mothers and fathers in child sleep research. Parents’ dysfunctional cognitions (their own sleep) and broader sleep-related practices (their own and child sleep) should be considered when exploring influences on child sleep. Results have possible implications for targets of interventions for child sleep problems and also potential implications for theoretical models of child sleep.