Study objectives: Sleep disruption is common in pregnancy, manifesting as insomnia in half of pregnant women as well as increasing objective nocturnal wakefulness across gestation. Despite potential overlap between insomnia and objective sleep disturbances in pregnancy, objective nocturnal wakefulness and its potential contributing factors remain uncharacterized in prenatal insomnia. The present study described objective sleep disturbances in pregnant women with insomnia and identified insomnia-related predictors of objective nocturnal wakefulness.
Methods: Eighteen pregnant women with clinically significant insomnia symptoms (n = 12/18 with DSM-5 insomnia disorder) underwent two overnight polysomnography (PSG) studies. Insomnia symptoms (Insomnia Severity Index), depression and suicidal ideation (Edinburgh Postnatal Depression Scale), and nocturnal cognitive arousal (Pre-Sleep Arousal Scale, Cognitive factor) were assessed before bedtime on each PSG night. Unique to Night 2, participants were awakened after 2 minutes of N2 sleep and reported their in-lab nocturnal (i.e. pre-sleep) cognitive arousal.
Results: Difficulty maintaining sleep was the most common objective sleep disturbance affecting 65%-67% of women across both nights, which contributed to short and inefficient sleep. Nocturnal cognitive arousal and suicidal ideation were the most robust predictors of objective nocturnal wakefulness. Preliminary evidence suggested nocturnal cognitive arousal mediates the effects of suicidal ideation and insomnia symptoms on objective nocturnal wakefulness.
Conclusions: Nocturnal cognitive arousal may facilitate upstream effects of suicidal ideation and insomnia symptoms on objective nocturnal wakefulness. Insomnia therapeutics reducing nocturnal cognitive arousal may benefit objective sleep in pregnant women presenting with these symptoms.
Study objectives: Obstructive sleep apnea (OSA) is reported to be highly prevalent among Aboriginal Australians. However, no studies have assessed the implementation and efficacy of continuous positive airway pressure (CPAP) therapy in this population. Hence, we compared the clinical, self-reported perception of sleep quality and polysomnographic (PSG) characteristics among Aboriginal patients with OSA.
Methods: Adult Aboriginal Australians who underwent both diagnostic (Type 1 and 2) and in-lab CPAP implementation studies were included.
Results: Total of 149 patients were identified (46% female, median age 49 years, body mass index 35 kg/m2). The OSA severity was 6% mild, 26% moderate, and 68% severe on the diagnostic PSG. On application of CPAP, there were significant improvements in; total arousal index (diagnostic 29 to 17/h on CPAP), total apnea-hypopnea index (AHI) (diagnostic 48 to 9/h on CPAP), non-rapid eye movement AHI (diagnostic 47 to 8/h on CPAP), rapid eye movement (REM) AHI (diagnostic 56 to 8/h on CPAP) and oxygen saturation (SpO2) nadir (diagnostic 77% to 85% on CPAP) (p < 0.001 for each). Following a single night of CPAP, 54% of patients reported sleeping "better than normal" compared to 12% following the diagnostic study (p = 0.003). In multivariate regression models, males had a significantly lesser change in REM AHI than females (5.7 events/hour less change (IQR 0.4, 11.1), p = 0.029).
Conclusions: There is substantial improvement in several sleep-related domains on the application of CPAP among Aboriginal patients with a good initial acceptance of treatment. Whether the positive impact observed in this study translates to better sleep health outcomes with long-term adherence to CPAP therapy is yet to be assessed.
[This retracts the article DOI: 10.1093/sleepadvances/zpac029.164.].
[This corrects the article DOI: 10.1093/sleepadvances/zpac045.].
[This corrects the article DOI: 10.1093/sleepadvances/zpac034.][This corrects the article DOI: 10.1093/sleepadvances/zpac040.].
[This retracts the article DOI: 10.1093/sleepadvances/zpac029.163.].
Study objectives: To explore the relationship among night-time smartphone use, sleep duration, sleep quality, and menstrual disturbances in young adult women.
Methods: Women aged 18-40 years were included in the SmartSleep Study in which they objectively tracked their smartphone use via the SmartSleep app between self-reported sleep onset and offset times (n = 764) and responded to a survey (n = 1068), which included background characteristics, sleep duration, sleep quality (Karolinska Sleep Questionnaire), and menstrual characteristics (International Federation of Gynecology and Obstetrics' definitions).
Results: The median tracking time was four nights (interquartile range: 2-8). Higher frequency (p = .05) and longer duration (p = .02) of night-time smartphone use were associated with long sleep duration (≥9 h), but not with poor sleep quality or short sleep duration (<7 h). Short sleep duration was associated with menstrual disturbances (OR = 1.84, 95% confidence interval [CI] = 1.09 to 3.04) and irregular menstruation (OR = 2.17, 95% CI = 1.08 to 4.10), and poor sleep quality was associated with menstrual disturbances (OR = 1.43, 95% CI = 1.19 to 1.71), irregular menstruation (OR = 1.34, 95% CI = 1.04 to 1.72), prolonged bleedings (OR = 2.50, 95% CI = 1.44 to 4.43) and short-cycle duration (OR = 1.40, 95% CI = 1.06 to 1.84). Neither duration nor frequency of night-time smartphone use was associated with menstrual disturbances.
Conclusions: Night-time smartphone use was associated with longer sleep duration, but not with menstrual disturbances in adult women. Short sleep duration and sleep quality were associated with menstrual disturbances. Further investigation of the effects of night-time smartphone use on sleep and female reproductive function in large prospective studies is needed.
Study objectives: Insomnia is common in the general population and is diagnosed based on self-reported sleep complaints. There is a frequent discrepancy between objectively recorded and self-reported sleep (sleep-wake state discrepancy), especially in individuals with insomnia. Although sleep-wake state discrepancy is well-documented in the literature, it is not well understood. This protocol describes the methodology of a randomized control study, which will examine whether providing monitoring and feedback about objectively recorded sleep with support for interpretation of sleep-wake state discrepancy improves insomnia symptoms and will explore the potential mechanisms of change.
Methods: Participants are 90 individuals with insomnia symptoms (Insomnia Severity Index [ISI] ≥10). Participants will be randomized to one of two conditions: (1) Intervention: feedback about objectively recorded sleep (actigraph and optional electroencephalogram headband) with guidance for data interpretation, (2) Control: sleep hygiene session. Both conditions will involve individual sessions and two check-in calls. The primary outcome is ISI score. Secondary outcomes include sleep-related impairment, symptoms of anxiety and depression, and other sleep and quality of life measures. Outcomes will be assessed using validated instruments at baseline and post-intervention.
Discussion: With increasing number of wearable devices that measure sleep, there is a need to understand how sleep data provided by these devices could be utilized in the treatment of insomnia. Findings from this study have the potential to better understand sleep-wake state discrepancy in insomnia and uncover new approaches to supplement current insomnia treatment.
Sleep is regulated by the homeostatic system and the circadian clock. Caffeine intake promotes wakefulness in Drosophila. In humans, caffeine is consumed on a daily basis and hence it is important to understand the effect of prolonged caffeine intake on both circadian and homeostatic regulation of sleep. Furthermore, sleep changes with age and the impact of caffeine on age-dependent sleep fragmentation are yet to be understood. Hence in the present study, we examined the effect of short exposure to caffeine on homeostatic sleep and age-dependent sleep fragmentation in Drosophila. We further assessed the effect of prolonged exposure to caffeine on homeostatic sleep and circadian clock. The results of our study showed that short exposure to caffeine reduces sleep and food intake in mature flies. It also enhances sleep fragmentation with increasing age. However, we have not assessed the effect of caffeine on food intake in older flies. On the other hand, prolonged caffeine exposure did not exert any significant effect on the duration of sleep and food intake in mature flies. Nevertheless, prolonged caffeine ingestion decreased the morning and evening anticipatory activity in these flies indicating that it affects the circadian rhythm. These flies also exhibited phase delay in the clock gene timeless transcript oscillation and exhibited either behavioral arrhythmicity or a longer free-running period under constant darkness. In summary, the results of our studies showed that short exposure to caffeine increases the sleep fragmentation with age whereas prolonged caffeine exposure disrupts the circadian clock.