The distinct roles of OSA and depression severity in day- and night-time symptomatology in OSA patients: a pilot study.

PURPOSE: Obstructive sleep apnoea (OSA) is a common sleep disorder and is associated with a number of comorbid conditions, including the frequent occurrence of depression. Notably, there is a considerate overlap in day- as well as night-time symptomatology in depression and OSA. In light of this, we aimed to disentangle the distinct effects of OSA and depression severity on day- and night-time symptomatology. METHODS: This pilot study (N = 320) utilized a retrospective chart review design and included both males and females who met the minimum diagnostic criteria for OSA. Daytime symptoms (sleepiness and fatigue) were assessed via questionnaires, while night-time symptoms were measured via polysomnography. RESULTS: Main findings include the following: (a) no association between OSA and depression severity, (b) depression severity significantly predicted increased sleepiness and fatigue (c) OSA severity significantly predicted increased stage 2 non-rapid eye movement sleep percentage, (d) OSA significantly predicted decreased stage 3 non-rapid eye movement sleep percentage and rapid eye movement sleep percentage. Overall, depression severity exerts the strongest influence on daytime symptomatology, while OSA severity exerts the strongest influence on night-time symptomatology. Moreover, with the exception of sleepiness, no overlap between day- and night-time findings was detected. CONCLUSION: OSA and depression, although comorbid, possibly constitute distinct disease processes in this population group. Consequently, solely devising treatment targeting a reduction in apnoea-hypopnoea index might not be sufficient in alleviating debilitating daytime symptoms in treatment-seeking individuals.

The South African 24-Hour Movement Guidelines for Birth to 5 Years: An Integration of Physical Activity, Sitting Behavior, Screen Time, and Sleep.

BACKGROUND: In December 2018, the South African 24-hour movement guidelines for birth to 5 years were released. This article describes the process used to develop these guidelines. METHODS: The Grading of Recommendations Assessment, Development, and Evaluation-ADOLOPMENT approach was followed, with some pragmatic adaptions, using the Australian guidelines for the early years as a starting point. A consensus panel, including stakeholders in early childhood development and academics, was formed to assist with the development process. RESULTS: At a face-to-face meeting of the panel, global and local literatures were considered. Following this meeting, a first draft of the guidelines (including a preamble) was formulated. Further reviews of these drafts by the panel were done via e-mail, and a working draft was sent out for stakeholder consultation. The guidelines and preamble were amended based on stakeholder input, and an infographic was designed. Practical "tips" documents were also developed for caregivers of birth to 5-year-olds and early childhood development practitioners. The guidelines (and accompanying documents) were released at a launch event and disseminated through various media channels. CONCLUSIONS: These are the first movement guidelines for South African and the first such guidelines for this age group from a low- and middle-income country.

Increased Awakenings From Non-rapid Eye Movement Sleep Explain Differences in Dream Recall Frequency in Healthy Individuals.

BACKGROUND: Dreaming is a universal experience, yet there is considerable inter-individual variability in dream recall frequency (DRF). One dominant model, the "arousal-retrieval" model, posits that intra-sleep wakefulness is required for dream traces to be encoded into long-term storage, essentially proposing that a better memory for dreams underlie increased DRF. A recent study utilizing polysomnography combined with an event-related potentials paradigm, provides direct support for this model by demonstrating increased intra-sleep wakefulness in a healthy population by comparing high frequency recallers (HFRs) and low frequency recallers (LFRs). Another study by the same group demonstrated increased regional cerebral blood flow in regions associated with dream production, supporting the premise that HFRs also may produce more dreams. HYPOTHESES: This study investigated the profile of nocturnal awakenings and dream production in healthy HFRs and LFRs. Hypothesis (1a): HFRs will spend significantly more time awake after sleep onset; (1b): HFRs will experience significantly more awakenings across the night, and from rapid eye movement (REM) sleep in particular; (2) HFRs will have significantly higher rates of dream production across the night as measured by REM density. METHODS: We studied two groups of healthy adults: HFRs (n = 19) and LFRs (n = 17) who underwent polysomnographic recordings on two non-consecutive nights. RESULTS: Hypothesis (1a) was confirmed: HFRs spent significantly more time awake after sleep onset. Hypothesis (1b) was partially confirmed: HFRs experienced significantly more awakenings across the night; however, awakenings from REM sleep were comparable. Interestingly, HFRs had significantly more awakenings, as well as a higher number of longer awakenings, from non-rapid eye movement (NREM) stage 2 sleep. Hypothesis (2) was not confirmed: There was no significant difference in rates of REM density between groups. CONCLUSION: This is the first study to provide evidence that awakenings from NREM 2 sleep might underlie increased DRF in HFRs. This finding coupled with null findings in relation to REM sleep variables, support the premise that inter-individual variability in DRF cannot be ascribed to differences in REM sleep parameters in healthy individuals. Instead, the data indicates that awakenings from NREM sleep is of particular importance in relation to DRF in a healthy population.

Prominence of hyperarousal symptoms explains variability of sleep disruption in posttraumatic stress disorder.

OBJECTIVE: Disrupted sleep is a central feature of posttraumatic stress disorder (PTSD). The precise nature of that disruption is not agreed upon, however, and there is no explanation for why sleep disruptions are detected in some PTSD-diagnosed individuals but not in others. We tested the novel proposition that PTSD-diagnosed individuals with prominent hyperarousal symptoms will have more disrupted sleep than those without such symptoms. METHOD: We assigned each of 57 female volunteers to 1 of 4 groups: PTSD + Hyperarousal (PTSD + HYP; n = 14), PTSD - Hyperarousal (n = 13), depression (n = 14), or healthy control (n = 16). Each experienced 1 night of polysomnographic recording in a sleep laboratory. RESULTS: General linear modeling confirmed that group status (i.e., being in the PTSD + HYP group rather than the other groups) predicted disrupted sleep quality most strongly. PTSD patients with prominent hyperarousal symptoms, relative to those without such symptoms, experienced reduced sleep efficiency, spent more time awake after sleep onset, and self-reported poorer sleep quality. CONCLUSION: These preliminary findings, although requiring replication in larger samples, suggest an important association between hyperarousal symptoms and sleep quality in PTSD, and may help explain why some PTSD-diagnosed individuals experience markedly disrupted sleep whereas others do not. (PsycINFO Database Record