Observed sleep/wakefulness and severity of dementia in an Alzheimer's disease special care unit

BACKGROUND: This study tested the hypothesis that behaviorally defined sleep disturbance among residents in a Special Care Unit (SCU) for Alzheimer's disease (AD) was related to the severity of their dementia. Previously, sleep laboratory studies have reported such relationships when sleep has been recorded polysomnographically over several nights. Observational studies of sleep have not shown such relationships, presumably because of the impression involved in determining sleep/wake state behaviorally. METHODS: Nightly sleep data based on observations made every two hours by nursing staff for a period of 13 to 18 months were examined for 47 AD residents with a mean age of 80.7 +/- 6.5 years. Level of dementia and functional capacity were assessed with the Mattis Dementia Rating Scale (DRS) and the Katz Activities of Daily Living Scale (ADL). RESULTS: Data indicated that these SCU residents experienced a moderately disturbed night of sleep an average of 24% +/- 10% of their nights in the facility and a severely disturbed night of sleep on 7% +/- 6% of those nights. More profound dementia was associated with more sleep disturbance; however, incapacity in ADLs, age, gender, and psychoactive medications were unrelated to such disturbances. CONCLUSIONS: The results indicate that patterns of relationships noted between laboratory-based measures of sleep and variables such as severity of dementia can be detected using behavioral observations of sleep, provided that the number of nights of observation are sufficiently large to offset the measurement error involved in their use.     

Sleep changes after 4 consecutive days of venlafaxine administration in normal volunteers

BACKGROUND: The purpose was to examine the effect of the antidepressant drug venlafaxine on sleep architecture and periodic leg movements of sleep (PLMS) in normal volunteers. METHOD: Eight normal volunteers were studied under laboratory sleep conditions as follows: 1 acclimatization night, 1 baseline night, and 4 consecutive nights of venlafaxine p.o. administration (75 mg during the first 2 nights and 150 mg the last 2 nights). RESULTS: Venlafaxine increased both wake time and sleep stage I. Sleep stages II and III were reduced. REM sleep time was reduced after the first venlafaxine dose, and, by the fourth night, REM sleep was completely suppressed in all volunteers. Six of the eight volunteers showed PLMS at a frequency above 25 per hour. CONCLUSION: Venlafaxine produces several sleep disturbances, which include abnormal leg movements.     

Use of dynamic two-dimensional transesophageal echocardiography for renal cell carcinoma with cavoatrial tumor thrombus

Previous investigations involving continuous blood pressure (BP) monitoring have shown an important alteration of the 24-hour BP profile in patients with obstructive sleep apnea syndrome (OSAS). We investigated the impact of REM sleep on the 24-hour BP cycle in 16 severe OSAS male patients (mean respiratory disturbance index = 66 +/- 16 events/hour of sleep), with hypertension (mean BP 162 +/- 21/105 +/- 11 mmHg World Health Organization (WHO) protocol). Two successive nights of polysomnography were performed, and arterial BP was monitored continuously during the second 24-hour period after brachial artery cannulation. During the daytime, subjects were kept awake and supine. At 3 p.m. BP was continuously monitored during quiet supine wakefulness for 20 minutes. Systolic, diastolic and mean BP and heart rate (HR) were analyzed and tabulated in mean values of 5 minute segments. Sleep/wake information were correlated with cardiovascular variables. Each uninterrupted REM sleep period was identified and comparison between the period of quiet supine wakefulness and REM sleep HR and BP values was performed. 8 OSAS patients presented a normal drop of the mean arterial BP during the nocturnal REM sleep periods compared to quiet supine wakefulness (mean value = -10.8 +/- 7.3 mmHg) ("dippers") while the other 8 subjects ("REM sleep non dippers"), revealed an elevated mean arterial BP during REM sleep (mean value = 18.9 +/- 10.9 mm Hg). The absence of the normal circadian BP dip seen during the nocturnal sleep period is considered as an indication of vascular risk. The REM sleep non dipping may play a role in this risk.     

Sleep inertia varies with circadian phase and sleep stage in older adults.

The purpose of our analysis was to determine if older adults show sleep inertia effects on performance at scheduled wake time, and whether these effects depend on circadian phase or sleep stage at awakening. Using the Digit Symbol Substitution Test, effects of sleep inertia on performance were assessed over the first 30 min after wake time on baseline days and when sleep was scheduled at different circadian phases. Mixed model analyses revealed that performance improved as time awake increased; that beginning levels of performance were poorest when wake time was scheduled to occur during the biological night; and that effects of sleep inertia on performance during the biological night were greater when awaking from non-REM (NREM) sleep than from REM sleep. Based on our current understanding of sleep inertia effects in young subjects, and previous reports that older subjects awaken at an earlier circadian phase and are more likely to have their final awakening from NREM sleep than younger adults, our findings suggest older adults may be more vulnerable to sleep inertia effects than young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Agonist regulation of beta-adrenergic receptors: immunoblotting and indirect immunofluorescence reveal agonist-induced lateral sequestration and loss of binding

Sleep and wakefulness were studied polygraphically in two adult male ferrets between the ages of 3 months and 2.5 years. Nine 24-hour recordings were obtained on different light/dark schedules, and one animal was also monitored for 3 days following administration of the serotonin synthesis inhibitor, parachlorophenylalanine. Stage scoring was accomplished utilizing criteria similar to those used in the cat. Certain modifications to the criteria were made to accommodate apparent differences in electrographic indicators of state. Mean daily percentages [+/- standard error of the mean (SEM)] for the major stages were: slow-wave sleep, 36.0 +/- 1.33; rapid eye movement (REM) sleep, 24.4 +/- 0.94; and wake, 39.4 +/- 1.17. Under laboratory conditions, ferrets spend over 60% of the time in sleep and 40.28% +/- 0.93% of total sleep time in REM sleep. The high amount of REM sleep is achieved by having a high number of REM sleep episodes rather than long REM periods. Sleep cycle length was computed in two ways: with long wake episodes removed, 16.7 +/- 0.4 minutes; and with all wake removed, 13.2 +/- 0.3 minutes. Sleep and waking indices in the ferret are compared to those in the cat and discussed with respect to predictions based on several constitutional variables. The high amount of REM sleep and the relative immaturity of the ferret at birth lends additional support for a functional role of REM sleep on ontogenetic development.     

Hospital ward policy and patients' sleep patterns: A multiple baseline study.

Altered sleep–wake and nap policies on 3 inpatient psychiatric wards housing 321 veterans (aged 30–45 yrs). Across a 111-day period, daytime naps were eliminated and a standard wake-up time was established sequentially across the 3 wards. Measures of average sleep onset latency (SOL), average wake time after sleep onset (WASO), and average total sleep time (TST) were obtained for each ward every night throughout the study. Results reveal consistent decreases in both SOL and WASO and consistent increases in TST across wards following the introduction of the experimental ward policy. Nonparametric analyses revealed that, for a majority of the beds on the 3 wards, sleep parameters showed improvement following the policy change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A negative association of schizophrenia with an allele of the HLA DQB1 gene among African-Americans

The present study investigated the relationship between the time of nocturnal onset of urinary 6-sulfatoxymelatonin (aMT6s) secretion, and the timing of the steepest increase in nocturnal sleepiness ("sleep gate"), as determined by an ultrashort sleep-wake cycle test (7 min sleep, 13 min wake). Twenty-nine men (mean age 23.8 +/- 2.7 years) participated. The ultrashort sleep-wake paradigm started at 0700 hr after a night of sleep deprivation and continued for 24 hr until 0700 hr the next day. Electrophysiological recordings were carried out during the 7-min sleep trials, which were then scored conventionally for sleep stages. Urinary aMT6s was measured every 2 hr. The results showed that the timing of the sleep gate was significantly correlated with the onset of aMT6s secretion. These results are discussed in light of the possible role of melatonin in sleep-wake regulation.     

Implementation of a quiet hour: effect on noise levels and infant sleep states

It is necessary to decrease environmental stimuli in order to provide developmentally supportive care to the very low birthweight (VLBW) infant, thereby enhancing the sleep/wake cycle and possibly physiologic stability. The purpose of this study was to determine if it was possible to decrease the noise level in the Developmental Unit, and promote sleep states in infants on the unit. After determining control noise levels and infant state, the last hour of each shift was designated a Quiet Hour. During this time, noise levels were monitored in the room in five locations. Infant sleep states were also noted. The results indicate that noise levels decreased significantly on two of the three shifts. Fewer infants were crying during the Quiet Hour than the control period (2.4 vs 14.3 percent), and more were in deep or light sleep (84.5 vs 33.9 percent). This study demonstrates that noise levels in Developmental Units can be significantly decreased, and that the decreased noise levels positively impact infant state. By enhancing sleep states, nurses can enhance the long term developmental outcome of the VLBW infant. However, the reduction of noise is highly dependent on the collaborative efforts of all health care providers within the unit.     

Internet-Based Treatment for Insomnia: A Controlled Evaluation.

This study investigated the effects of an Internet-based intervention for insomnia. Participants who met criteria for insomnia (N = 109) were randomly assigned to either a cognitive-behavioral self-help treatment or a waiting list control condition. The 5-week intervention mainly consisted of sleep restriction, stimulus control, and cognitive restructuring. Sleep diary data were collected for 2 weeks at baseline and at posttreatment. The dropout rate was 24% (n = 28). Results showed statistically significant improvements in the treatment group on many outcome measures, including total sleep time, total wake time in bed, and sleep efficiency. However, improvements were also found in the control group. Overall, between-groups effect sizes were low, with the exception of the Beliefs and Attitudes About Sleep Scale (Cohen's d = .81). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correlation between ventilation and EEG-defined arousal during sleep onset in young subjects

In studies of elderly individuals, ventilation and EEG-defined arousal have been shown to vary periodically and synchronously. Such results have been interpreted as indicating the primacy of sleep/wake state in causing ventilatory instability during sleep onset. However, because the elderly individuals studied were periodic breathers, the results do not unequivocally support this conclusion. In this study the relationship between ventilation and EEG-defined arousal was assessed in a group of 21 young, healthy men in whom ventilatory instability during sleep onset was not periodic. Ventilation and EEG (O1-A2) recordings were collected, and the longest uncontaminated periods from early and late in sleep onset were selected for subsequent analysis. The 84 time series (21 subjects, 2 variables, and 2 occasions in sleep onset) were subjected to spectral analysis to identify periodicity, and the relationship between the two variables was determined by cross-correlational methods. The results indicated that the time series were nonperiodic, yet significant correlations were observed between the two variables. The data support the view that during sleep onset ventilatory instability is driven primarily by variations in sleep/wake arousal level.     

The continuing dilemma concerning medical versus surgical management of patients with acute type B dissections

In the free-running circadian rhythms of 14 human subjects (4 females, 10 males) who lived singly in an isolation unit without temporal clues, locomotor activity was recorded by means of contact plates installed below the carpet in the main room. During sleep, movements in bed were picked up by spring contacts attached to the mattress. In all subjects, the hourly means of locomotion during wakefulness (alpha) were negatively correlated with the duration of alpha to such an extent that the total amount of locomotion per cycle remained constant when alpha varied from 14 to 23 hr. The hourly values of movements in bed were independent of the duration of sleep (rho), so that the total number of movements was almost proportional to rho. The "homeostatic control" of locomotion during wake time is considered as a means to conserve energy when the duration of wakefulness increases.     

Genetic polymorphism of AHSG, FXIIIB, HP and PLG serum proteins in six Jewish groups in Israel

This study was designed to evaluate the conventional techniques of assessing sleep, nursing and patient report, of inpatients on a clinical psychiatric unit. Nurses assessed sleep/wake status at hourly checks and patients completed a sleep diary. For three nights patients wore a wrist actigraph, a portable instrument which provides objective data about sleep/wake activity. The nursing and patient data obtained were compared with actigraphy data. Nursing staff evaluated sleep with satisfactory agreement (76.5% night 1 and 81.6% night 3) that improved over the first three nights of hospitalization (p < 0.03). When the nurses' report did not agree with the actigraph, they tended to overestimate sleep. Patients tended to underestimate their total sleep time and total time awake after sleep onset. Time in bed and initial sleep latency were overestimated. There was great intersubject variability, making determination of agreement impossible. This data suggest that treatment teams on psychiatric units should in general consider nursing reports of sleep more accurate than patient self-report. However, since nursing staff and patients observe different aspects of sleep, both sources of data are important to inpatient treatment teams on clinical units.     

Reconsidering the role of sleep for motor memory.

Previous studies suggest that sleep may play an important role in memory consolidation of motor skills. It has been difficult, however, to tease apart the effect of sleep from circadian and homeostatic factors. We examined the effect of sleep on a popular motor sequence task, utilizing a design that controlled for time of day and time since sleep between wake and sleep groups. When these factors were controlled, there was no benefit of sleep to motor memory, suggesting that previous work may have been influenced by circadian and homeostatic confounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Actimetry: simplified analysis of wake-sleep rhythms in the newborn. Preliminary results

Actimetry in newborns is relevant if two actimeters are placed, one on each ankle. This study has been conducted on nine normal three days old newborns. It has shown an indisputable link between the lack of activity and the observed sleep during the night that was missing during the day. The longest period of wake was recorded during the day and the longest period of sleep or inactivity was during the night. This study has confirmed the existence of an ultradian rhythm of quiet sleep and wake. It is also possible that a beginning of a circadian rest-activity rhythm exists already in the neonatal period, that is still discussed in the literature.     

Effect of night smoking, sleep disturbance, and their co-occurrence on smoking outcomes.

Recent evidence suggests that smoking during the night is an indicator of nicotine dependence and predicts smoking cessation failure. Night smokers are likely to experience disturbance to their sleep cycle when they wake to smoke, but we are not aware of the prevalence of night smokers' self-reported sleep disturbance. Because sleep disturbance also predicts smoking cessation failure, we examined how the pre-cessation risk factors of night smoking and sleep disturbance, and their co-occurrence, predict smoking cessation failure in a 6-week double-blind randomized controlled trial examining whether naltrexone augments the efficacy of the nicotine patch (O'Malley et al., 2006). Smokers (N = 385) completed the Pittsburgh Sleep Quality Index (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989) and a single item of waking at night to smoke pre-cessation. Smoking status was determined at weeks 1, 6, 24, and 48 weeks after quitting. The two main findings were: (a) night smokers reported significantly greater sleep disturbance than nonnight smokers; and (b) smokers with co-occurring night smoking and sleep disturbance experienced significantly greater risk for smoking than smokers with neither risk factor. Results suggest that individuals who both wake during the night to smoke and report clinically-significant sleep disturbance represent a high-risk group of smokers. Future smoking cessation treatment might incorporate strategies related to managing these smokers' sleep habits and physiological dependence on nicotine in order to bolster their cessation outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The relationship of luteinizing hormone secretion to sleep in women during the early follicular phase: effects of sleep reversal and a prolonged three-hour sleep-wake schedule

The relationship of luteinizing hormone (LH) secretion to sleep in adult women was investigated in two ways: an acute 180 degrees sleep-wake cycle reversal in a group of six women and a schedule in which a young woman engaged in a three hour sleep-wake cycle (two hours awake, one hour allowed for sleep continuously for ten days--the study was carried out on the eighth day). Each subject in the reversal study had a baseline period during which plasma samples were collected every twenty minutes for twenty-four hours and nocturnal sleep was monitored electrophysiologically during the early follicular phase of the menstrual cycle. During a succeeding cycle, the study was repeated after sleep-wake reversal. LH secretory patterns were analyzed by comparing the 24-hour mean plasma LH concentration with the hourly averages in percentage terms, using Stage 2 sleep onset as the zero point. LH secretion was depressed to approximately the same degree in both the baseline and reversal studies. The average hourly percentage difference from the 24-hour mean for the four-hour period following sleep onset was -13.4% and -13.1% for the baseline and reversal, respectively. These percentage deviations represented practically the entire negative deviation for the 24-hour period in both studies. The difference between the first four-hour period after sleep onset and the second was significant. The subject on a three-hour cycle had a baseline in which a large decrease in LH secretion occurred after sleep onset (-52.2% during the third hour). Her LH secretory pattern during the three-hour sleep-wake schedule was characterized by a fall during sleep periods, particularly when slow wave sleep (SWS) predominated. However, no correlation was found between specific sleep stages and LH secretion in the six women of the reversal study. These results confirm a relationship of LH secretion to sleep in adult women, one which is different from that described during puberty.     

Universal Total Wrist Implant: experience with a carpal component fixed with three screws

The purpose of this report is to summarize data from a sample of 230 residents in eight nursing homes (NHs) that are relevant to the development of environmental and behavioral interventions for sleep. Four conclusions can be drawn: (1) there is strong evidence that the nighttime sleep of these residents was adversely affected by environmental noise and light; (2) residents appear to spend substantial time in bed and sleeping during the day; (3) there are significant differences between some homes in the amount of time that residents spend in bed and sleeping during the day, as well as the frequency of nighttime awakenings associated with environmental events; and (4) residents' preference and nighttime noise source data suggest that a multifaceted intervention to improve sleep hygiene could successfully implemented in the NH setting. An intervention addressing these issues may result in improved sleep and overall well-being for a substantial portion of the NH population.     

Correction of acidosis in dialysis patients increases branched-chain and total essential amino acid levels in muscle

The following four issues were assessed in a group of 110 adults between the age of 20 and 59y: (1) the effect of age (regarded as a continuous variable) on polysomnographic sleep characteristics, habitual sleep-diary patterns, and subjective sleep quality; (2) the effects of age on morningness-eveningness; (3) the effects of morningness-eveningness on sleep, after controlling for the effects of age; and (4) the role of morningness-eveningness as a mediator of the age and sleep relationship. Increasing age was related to earlier habitual waketime, earlier bedtime, less time in bed and better mood and alertness at waketime. In the laboratory, increasing age was associated with less time asleep, increased number of awakenings, decreased sleep efficiency, lower percentages of slow-wave sleep (SWS) and rapid eye movement (REM) sleep, higher percentages of Stage 1 and 2, shorter REM latency and reduced REM activity and density. Increasing age was also associated with higher morningness scores. After controlling for the effects of age, morningness was associated with earlier waketime, earlier bedtime, less time in bed, better alertness at waketime, less time spent asleep, more wake in the last 2 h of sleep, decreased REM activity, less stage REM (min and percentage), more Stage 1 (min and percentage) and fewer minutes of Stage 2. For one set of variables (night time in bed, waketime, total sleep time, wake in the last 2 h of sleep and minutes of REM and REM activity), morningness-eveningness accounted for about half of the relationship between age and sleep. For another set of variables (bedtime, alertness at waketime, percentages of REM and Stage 1), morningness-eveningness accounted for the entire relationship between age and sleep. In conclusion, age and morningness were both important predictors of the habitual sleep patterns and polysomnographic sleep characteristics of people in the middle years of life (20-59 y).