Sleep In Healthy Adults Research Articles

Validation of an automated wireless system to monitor sleep in healthy adults

The availability of a reliable system to record sleep stage measures easily and automatically in ambulatory settings could be of utility for research and clinical work. The aim of this study was to evaluate a novel wireless system (WS) that does not require skilled preparation for the automatic collection and scoring of human sleep. Twenty-nine healthy adults underwent concurrent sleep measurement via the WS, polysomnography (PSG) and an actigraph (ACT) in a sleep laboratory for one assessment night preceded by an acclimation night. The PSG recordings were scored by two experienced trained technicians from separate laboratories. Each recording was scored by both technicians to Rechtschaffen and Kales (R&K) criteria. The WS and ACT were compared with each of the PSG scores and a consensus PSG score, and the PSG scores were compared with each other. Inter-rater agreement was assessed for each pair over all pooled epochs by percentage agreement, Cohen's kappa and intraclass correlation coefficient. The WS agreement with each of the two PSG scores for sleep stages was 75.8 and 74.7%, respectively. WS agreement with each of the two PSG scores for sleep/wakefulness was 92.6 and 91.1%, ACT agreement with PSG was 86.3 and 85.7%. The PSG scorers' agreement with each other for sleep stages was 83.2%, and for sleep/wakefulness was 95.8%. The findings from the current study indicate that the WS may provide an easy to use and accurate complement to other established technologies for measuring sleep in healthy adults.

The heart rate response to spontaneous arousal from sleep is reduced in children with Down syndrome referred for evaluation of sleep-disordered breathing

Arousal from sleep in healthy adults is associated with a large, transient increase in heart rate (HR). Individuals with Down syndrome (DS) have attenuated cardiovascular responses to autonomic tests during wakefulness. We tested the hypothesis that the HR response to arousal from sleep is reduced in children with DS and obstructive sleep apnea (OSA) compared with healthy children. Twenty children aged 3-17 yr referred for investigation of sleep-disordered breathing (10 DS, and 10 OSA controls) matched for age and obstructive apnea/hypopnea index underwent routine overnight polysomnography. In addition, 10 nonsnoring controls from the general community were studied. Beat-by-beat HR was analyzed from 15 s pre- to 15 s post-spontaneous arousals and compared between groups using two-way ANOVA with repeated measures. Data are presented as means + or - SE. For both rapid eye movement (REM) and non-REM (NREM), arousals were associated with a significant increase in HR in all groups (peak response NREM: DS, 118 + or - 1% at 3 s; OSA controls, 124 + or - 2% at 4 s; and healthy controls, 125 + or - 3% at 4 s; and peak response REM: DS, 116 + or - 2% at 4 s; OSA controls, 123 + or - 3% at 4 s; and healthy controls, 125 + or - 4 at 4 s; P < 0.001 for all). Post hoc analysis revealed that HR in the DS group was significantly lower than both control groups at 1-4 s in NREM and at 4 to 5 s in REM (P < 0.05 for all). In conclusion, the HR response to spontaneous arousal from sleep is reduced in children with DS and OSA compared with healthy children. This attenuated cardiovascular response could be due to reduced sympathetic activation or blunted vagal withdrawal and may have implications for the child with DS and OSA.

Somatostatin analog treatment is associated with an increased sleep latency in patients with long-term biochemical remission of acromegaly

Background Somatostatin analogs induce alterations in sleep in healthy adults. Presently, it is unknown whether somatostatin analog treatment affects sleep parameters in patients with acromegaly. Design Case-control study. Patients and measurements We assessed sleepiness and sleep patterns in 62 adult patients (32 men, age 61 years (33–88 years) controlled by surgery alone or postoperative radiotherapy (69%), and/or somatostatin analogs (31%). We used two validated sleep questionnaires (Epworth sleepiness score and Münchener chronotype questionnaire). Patient outcomes were compared to controls. Results Sleep duration and timing of sleep were not different in patients compared to controls. However, sleepiness score was increased in all patients compared to controls: 6 (1–20) vs. 4 (0–14), P = 0.014 (median (range)), reflecting increased daytime sleepiness. Snoring was reported in 68% of both patients and controls ( P = 0.996), observed apnoea’s and restless legs in 23% and 37% of patients compared to 12% and 21% of controls ( P = 0.062 and P = 0.031, resp.). In addition, sleep latency was increased in patients treated by somatostatin analogs compared to patients cured by surgery and/ or radiotherapy (52 ± 48 min vs. 26 ± 40 min, P = 0.005), resulting in a delayed sleep onset (24:08 ± 1:26 h vs. 23:25 ± 0:43 h, P = 0.053). Sleep duration was unaffected. Conclusions Daytime sleepiness is increased in a homogeneous cohort of patients in long-term remission from acromegaly. In addition, somatostatin analog treatment increases sleep latency and delays sleep onset in patients with long-term biochemical control of growth hormone overproduction without altering total sleep duration.

Alexithymia and polysomnographic measures of sleep in healthy adults.

This study examined associations between alexithymia and objective characteristics of sleep (latencies, stages, and amount and patterning of REM sleep) that may contribute to subjective reports of poor sleep quality and impaired dream recall among alexithymic people. Fifty healthy, normally sleeping adults from the community completed the 20-item Toronto Alexithymia Scale and slept uninterrupted for one night in the laboratory while polysomnography was conducted. Various measures of sleep latency, sleep stages, and REM sleep-related variables were obtained, and analyses correlated these sleep measures with alexithymia, controlling for age, sex, and level of depressed affect. Higher alexithymia scores were significantly related to increased stage 1 (light) sleep and decreased stage 3/4 (deep) sleep. Alexithymia was unrelated to overall sleep efficiency or percentage of stage 2 sleep. Alexithymia was related to more frequent REM episodes and more stage 1 sleep during and immediately after REM episodes but was unrelated to the absolute amount of REM sleep. Alexithymia was also related to an earlier onset of the first REM episode. Alexithymia is associated with more light sleep and less deep sleep, which may contribute to subjective reports of poor sleep and increased sleepiness, fatigue, and somatic symptoms. Although alexithymia is not associated with an overall reduction of REM sleep, the increased frequency of episodes of REM that are interrupted and followed by light sleep rather than complete awakenings may contribute to limited dream recall.

The effects of nefazodone on sleep in depressed patients and healthy controls

This paper briefly reviews the effects of antidepressants on sleep, and highlights recent studies on the effects of nefazodone on sleep in healthy adults and those with major depressive disorders. Studies indicate significant improvement in sleep quality, decreased light sleep, and a reduction in nocturnal awakenings on nefazodone with minimal effect on REM sleep. The clinical relevance of these sleep findings is also discussed.

Mandibular posture during sleep in healthy adults

To test whether the mandible opens more during deep sleep and whether the mandibular position is affected by body position during sleep, the vertical mandibular position was recorded intraorally using a magnet sensor at the same time as a standard sleep study in seven normal healthy male adults. Measurements were recorded during the period before sleep onset (WAKE) and during sleep. Two-way ANOVA showed that vertical mandibular position was significantly affected by sleep stage but not by body position (supine vs lateral recumbent). The proportion of time during which the mandible was in a near-closed position (0–2.5 mm) significantly and progressively decreased, and significantly more time was spent at wider gapes (2.5–5 mm) as non-rapid-eye-movement (NREM) sleep deepened. In REM sleep, the proportion of time during which the mandible was at wider gapes was significantly greater than in WAKE and stage 1 (but not later stages) of NREM sleep. It was concluded that mandibular posture during sleep in healthy adults is significantly influenced by sleep stage but not by body position. Mandibular opening progressively increases with the depth of NREM sleep stage, and the mandible is more open in REM sleep than in light NREM sleep.