Journal of sleep research
-
Journal of sleep research · Jun 2013
Randomized Controlled Trial Comparative StudyHigh-altitude hypoxia and periodic breathing during sleep: gender-related differences.
High-altitude exposure is characterized by the appearance of periodic breathing during sleep. Only limited evidence is available, however, on the presence of gender-related differences in this breathing pattern. In 37 healthy subjects, 23 male and 14 female, we performed nocturnal cardio-respiratory monitoring in the following conditions: (1) sea level; (2) first/second night at an altitude of 3400 m; (3) first/second night at an altitude of 5400 m and after a 10 day sojourn at 5400 m. ⋯ In conclusion, at high altitude, nocturnal periodic breathing affects males more than females. Females started to present a significant number of central sleep apneas only at the highest reached altitude. After 10 days at 5400 m gender differences in the apnea-hypopnea index similar to those observed after acute exposure were still observed, accompanied by differences in respiratory cycle length.
-
Journal of sleep research · Apr 2013
Clinical TrialThe impact of prolonged violent video-gaming on adolescent sleep: an experimental study.
Video-gaming is an increasingly prevalent activity among children and adolescents that is known to influence several areas of emotional, cognitive and behavioural functioning. Currently there is insufficient experimental evidence about how extended video-game play may affect adolescents' sleep. The aim of this study was to investigate the short-term impact of adolescents' prolonged exposure to violent video-gaming on sleep. ⋯ Heart rate did not differ significantly between video-gaming conditions during pre-sleep game-play or the sleep-onset phase. Results provide evidence that prolonged video-gaming may cause clinically significant disruption to adolescent sleep, even when sleep after video-gaming is initiated at normal bedtime. However, physiological arousal may not necessarily be the mechanism by which technology use affects sleep.
-
Journal of sleep research · Dec 2012
Comparative StudyProgressive dopamine and hypocretin deficiencies in Parkinson's disease: is there an impact on sleep and wakefulness?
Sleep-wake disturbances are frequent in patients with Parkinson's disease, but prospective controlled electrophysiological studies of sleep in those patients are surprisingly sparse, and the pathophysiology of sleep-wake disturbances in Parkinson's disease remains largely elusive. In particular, the impact of impaired dopaminergic and hypocretin (orexin) signalling on sleep and wakefulness in Parkinson's disease is still unknown. We performed a prospective, controlled electrophysiological study in patients with early and advanced Parkinson's disease, e.g. in subjects with presumably different levels of dopamine and hypocretin cell loss. ⋯ This suggests that dopamine and hypocretin deficiency differentially affect sleep and wakefulness in Parkinson's disease. Poorer sleep quality is linked to dopamine deficiency and other disease-related factors. Despite hypocretin cell loss in Parkinson's disease being only partial, disturbed hypocretin signalling is likely to contribute to excessive daytime sleepiness in Parkinson patients.
-
Journal of sleep research · Dec 2012
The effect of flow limitation on the cardiorespiratory response to arousal from sleep under controlled conditions of chemostimulation in healthy older adults.
The influence of flow limitation on the magnitude of the cardiorespiratory response to arousal from sleep is of interest in older people, because they experience considerable flow limitation and frequent arousals from sleep. We studied older flow-limiting subjects, testing the hypothesis that the cardiorespiratory activation response would be larger when arousal occurred during flow limitation, compared to no flow limitation, and chemical stimuli were controlled. In 11 older adults [mean ± standard deviation (SD) age: 68 ± 5 years] ventilation was stabilized using continuous positive airway pressure, and flow limitation was induced by dialling down the pressure. ⋯ The pre-post-arousal differences in ventilation reflected significant pre-arousal suppression (due to flow limitation) plus post-arousal activation. In summary, the cardiovascular response to arousal from sleep is not influenced by flow limitation at the time of arousal, when chemical stimuli are controlled in older adults. This finding may contribute to the decreased cardiovascular burden associated with sleep-disordered breathing reported in older adults, although our data do not exclude the possibility that flow limitation in the presence of mild hypoxic hypercapnia could increase the cardiovascular response to arousal.
-
Journal of sleep research · Oct 2012
Internight sleep variability: its clinical significance and responsiveness to treatment in primary and comorbid insomnia.
Although sleep diary and actigraphy data are usually collected daily for 1 or 2 weeks, traditional analytical approaches aggregate these data into mean values. Internight variability of sleep often accompanies insomnia. However, few studies have explored the relevance of this 'construct' in the context of diagnosis, clinical impact, treatment effects and/or whether having 'variable sleep' carries any prognostic significance. ⋯ Higher SOL variability was associated with worse treatment outcomes within the PI group, whereas higher WASO variability was correlated with better treatment outcomes within the CMI group. Sleep variability differences across insomnia diagnoses, along with their distinctive correlates, suggest that mechanisms underlying the sleep disruption/complaint and treatment response in both patient groups are distinct. Further studies are warranted to support variability as a useful metric in insomnia studies.