Percentage Of Sleep Research Articles

Sleep and Respiratory Parameters After Lung Transplantation in Adult Patients With Cystic Fibrosis.

We aimed to explore the prevalence and predictive factors of sleep-disordered breathing (SDB) in patients with cystic fibrosis (pwCF) after lung transplantation (LTX). We prospectively recruited adult pwCF who underwent LTX in our hospital from 2013 to 2022 and invited them for an attended overnight polysomnography (PSG) 1year after transplantation. The apnea-hypopnea index (AHI) was the primary outcome, and SDB was defined as an AHI≥5. Demographic, anthropometric, cardiometabolic, drug treatment, and pulmonary function variables were compared between pwCF with and without SDB. Multiple regression analysis was used to identify significant predictors of SDB. For a subset of participants who had available PSG before transplantation, sleep parameters were compared pre-post transplantation. Sixty-two pwCF (31 females) were enrolled. Thirty participants had SDB, but only 11 of them had moderate-to-severe SDB (AHI≥15). The average Epworth Sleepiness Scale (ESS) score indicated the absence of excessive daytime sleepiness. Older age (p<0.001), male sex (p<0.001), and smaller thoracic gas volume (p=0.002) significantly predicted higher AHI. Comparison between pre- and post-transplantation polysomnographic data showed a significant increase in the percentage of slow wave sleep (p=0.047), as well as a significant improvement in mean nocturnal oxygen saturation (p=0.007). A statistically significant increase in the AHI was also observed (p=0.047), but its clinical importance is uncertain (p=0.476 for the increase in the ESS score). We may conclude that SDB is prevalent in pwCF after LTX, but its severity is mild. Older male pwCF with greater improvement in lung hyperinflation after transplantation might be at risk for SDB and should be followed for symptoms or signs of sleep apnea.

The impact of sleep disturbances on treatment efficacy and prognosis in patients with depressive and anxiety disorders.

Little was known about the relationship between sleep disturbances and depressive and anxiety disorders, as well as the efficacy of treatment regimens. During 2021 to 2023, a total of 417 participants were screened by Hamilton Depression Rating Scale (HAMD-17) and Hamilton Anxiety Rating Scale (HAMA-14) for psychological status, and Pittsburgh sleep quality index (PSQI) assessment. 409 participants were finally enrolled, of which 188 (45.97%) were suffered from sleep disorders. All participants were received polysomnography (PSG) followed by six-week pharmacological treatment of escitalopram and zopiclone, and finally assessed by HAMD-17 and HAMA-14 for treatment efficacy. PSG monitoring indicated that participants with depression experienced prolonged rapid eye movement sleep latency (REMSL) and increased wakefulness after sleep onset (WASO) (P=0.030 and P=0.002, respectively). Those with anxiety disorders demonstrated a significantly higher percentage of non-rapid eye movement sleep (NREM%) and reduced WASO (P=0.013 and P=0.001, respectively). After six-weeks pharmacological treatment, participants with or without sleep disorders exhibited with similar efficacy outcomes of depression and anxiety disorders (P>0.05). However, every point of PSQI increment at baseline would decrease 0.78 and 0.85 times of probability of effective pharmacological treatment of depression and anxiety disorders. Moreover, participants with both effective outcomes of depression and anxiety disorders were found significant shorter sleep onset latency (SOL) (P<0.001). The insights gained underscore the necessity of considering sleep disturbances in enhancing the overall effectiveness of pharmacological treatments for depression and anxiety disorders.

Sleep Disturbances in Amyotrophic Lateral Sclerosis and Prognostic Impact—A Retrospective Study

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease associated with sleep disturbance, namely insomnia and sleep-disordered breathing. This study aims to evaluate the overall sleep characteristics of ALS patients, their association with lung function tests, and possible predictive survival factors. We conducted a retrospective observation study among ALS patients monitored during a pulmonology consultation. Type one polysomnography (PSG) and lung function tests were performed once the patients presented with sleep-related symptoms, and the relationship between their parameters was assessed, as well as a survival analysis. We included 35 patients, with an overall diminished sleep efficiency, a partially conserved forced vital capacity (FVC), and low maximal inspiratory pressure (MIP). A positive correlation between FVC and REM sleep percentage was observed. A survival analysis showed that a normal rapid eye movement (REM) sleep percentage and respiratory disturbance index (RDI) ≥ 15/h were independent predictors of survival. We observed a trend for higher sleep quality in patients with conserved lung function. A better sleep quality was associated with a higher survival. Obstructive events (reduced or absence of airflow associated with continued or increased inspiratory effort) did not seem to impact survival.

Morning tiredness and insomnia symptoms are associated with increased blood pressure in midlife women

ObjectivesThe objective of this study was to investigate how blood pressure, sleep architecture, sleep-disordered breathing, body habitus, and levels of serum follicle-stimulating hormone are associated with symptoms of insomnia and sleep quality during menopausal transition. Methods64 healthy premenopausal women (aged 45–47 years) were recruited to the study. Data were collected at baseline and at 10-year follow-up during sleep laboratory and laboratory visits. A sleep questionnaire was used to evaluate sleep quality and insomnia symptoms. Data were analysed using multiple linear and logistic regression with a backward method. ResultsDuring the menopausal transition, a change in insomnia symptoms was associated with a change in morning systolic blood pressure (β = 0.114 (CI95% 0.023–0.205), p = 0.016). At follow-up, at the age of 56, a higher percentage of REM sleep was associated with a lower odds of restless sleep (OR = 0.842 (95 % CI 0.742–0.954), p = 0.007), while both higher systolic and diastolic evening blood pressure was associated with an increased odds of morning tiredness.OR = 1.047 (95 % CI 1.003–1.092), p = 0.034 and OR = 1.126 (95 % CI 1.018–1.245), p = 0.007, respectively. ConclusionsIn healthy midlife women, a change blood pressure is related to the development of insomnia symptoms during menopausal transition. In postmenopausal women, a high evening blood pressure may be associated with morning tiredness and a reduced amount of REM sleep may be perceived as restless sleep.

Polysomnographic and clinical characteristics of sleep apnea headache patients.

Sleep apnea headache can be defined as a persistent, widespread, throbbing headache that occurs recurrently, is not accompanied by any additional symptoms after waking up, and usually resolves within four hours. Diagnosis of the condition requires confirmation through polysomnography with an apnea-hypopnea index of at least 5, indicating the presence of obstructive sleep apnea syndrome (OSAS). While sleep apnea headaches are common in 10-15% of individuals with OSAS, morning headaches are experienced by 5% of this population. The aim of this study is to examine both polysomnographic and clinical features associated with sleep apnea headache in individuals confirmed to have OSAS by polysomnography. The study was conducted in the sleep center of University of Health Science, Erenköy Mental and Nervous Disease Training and Research Hospital. We have examined the clinical and polysomnographic data of the patients with sleep apnea headache (SAH) diagnosed according to IHS-3 criteria retrospectively and grouped the patients as mild, moderate and severe OSAS. Patients with morning headache except sleep apnea headache and under PAP titration treatment were excluded. The differences between the sleep macro structures of patients with (WSAH) and without sleep apnea headache (WOSAH) were examined. The WSAH group consisted of 384 participants and the control group (WOSAH) consisted of 294 participants The mean age was 46.29 ± 12.18 and 45.08 ± 12.62 years, respectively. Patients in the WSAH group had significantly higher scores on the Epworth Sleepiness Scale (ESS) (p = 0.004) and higher periodic limb movement index (PLMI) (p = 0.014) compared to the WOSAH group. WSAH patients exhibited shorter wake times after sleep onset (WASO) and lower scores on the sleep quality index, in contrast to WOSAH patients. Additionally, within the WSAH group, there was a negative correlation between age and several sleep parameters, including total sleep parameters. A positive correlation was observed between sleep duration (p = 0.009), waking up after sleep (p = 0.043), sleep efficiency (p = 0.001) and apnea-hypopnea index (AHI) (p = 0.018). Additionally, ESS scores were positively correlated with AHI and total awake time (p = 0.000 and p = 0.008, respectively), while negatively correlated with stage N3 sleep percentage and mean minimum oxygen level (p = 0.001 and p = 0.020, respectively) in the WSAH group. The causes and possible mechanisms of sleep apnea headache are not fully clarified and the underlying processes are not fully understood. Sleep apnea headaches appear to be related to disturbances in nocturnal sleep. Dysregulation in regions that modulate sleep and nociception may be one possible mechanism.

Relationship Between High Frequency Component of Heart Rate Variability and Delta EEG Power During Sleep in Women With Irritable Bowel Syndrome Compared to Healthy Women.

To explore the relationship between the high frequency (HF) heart rate variability (HRV) and electroencephalogram (EEG) delta band power in women with irritable bowel syndrome (IBS) versus healthy control women. Twenty women with IBS and twenty healthy controls were studied over three consecutive nights using polysomnography in a sleep laboratory. To avoid the first night effect, only second-night data were analyzed. Power spectral analysis was applied to HRV and EEG recordings. The linear system coherence/phase analysis assessed the relationship between normalized HF power of HRV and normalized delta band power of EEG during the first four NREM-REM sleep cycles. Women with IBS exhibited a significantly higher percentage of NREM sleep, higher normalized HF, lower normalized low frequency (LF) and decreased LF/HF ratio of HRV in the first four NREM-REM sleep cycles compared to controls. Additionally, their normalized delta band power was significantly lower in these sleep cycles and over the whole night. The phase shift between HF and delta band power was significantly longer in the IBS group. While the coherence between normalized HF and normalized delta band power was lower in the IBS group, the difference was not statistically significant. The coherence/phase analysis showed a dysregulated interaction between autonomic and central nervous systems in women with IBS, manifested by increased lag time between cardiac and EEG delta band power compared to healthy controls. Whether this dysregulation contributes to the pathophysiology of IBS remains to be determined.

Impact of mini-dose dexmedetomidine supplemented analgesia on sleep structure in patients at high risk of obstructive sleep apnea: a pilot trial.

Obstructive sleep apnea (OSA) is common in surgical patients and associated with worse perioperative outcomes. To investigate the effect of mini-dose dexmedetomidine supplemented analgesia on postoperative sleep quality pattern in patients at high risk of OSA. A pilot randomized, double-blind, placebo-controlled trial. A tertiary university hospital in Beijing, China. One hundred and fifty-two adult patients who had a STOP-Bang score ≥3 and a serum bicarbonate level ≥28 mmol/L and were scheduled for major noncardiac surgery between 29 January 2021 and 20 September 2022. After surgery, patients were provided with high-flow nasal cannula and randomized in a 1:1 ratio to receive self-controlled opioid analgesia supplemented with either mini-dose dexmedetomidine (median 0.02 μg/kg/h) or placebo. We monitored polysomnogram from 9:00 pm to 6:00 am during the first night. Our primary outcome was the percentage of stage 2 non-rapid eye movement (N2) sleep. Secondary and exploratory outcomes included other postoperative sleep structure parameters, sleep-respiratory parameters, and subjective sleep quality (Richards-Campbell Sleep Questionnaire; 0-100 score range, higher score better). All 152 patients were included in intention-to-treat analysis; 123 patients were included in sleep structure analysis. Mini-dose dexmedetomidine supplemented analgesia increased the percentage of stage N2 sleep (median difference, 10%; 95% CI, 1 to 21%; p = 0.029); it also decreased the percentage of stage N1 sleep (median difference, -10%; 95% CI, -20% to -1%; p = 0.042). Other sleep structure and sleep-respiratory parameters did not differ significantly between the two groups. Subjective sleep quality was slightly improved with dexmedetomidine on the night of surgery, but not statistically significant (median difference, 6; 95% CI, 0 to 13; p = 0.060). Adverse events were similar between groups. Among patients at high risk of OSA who underwent noncardiac surgery, mini-dose dexmedetomidine supplemented analgesia may improve sleep quality without increasing adverse events. Clinicaltrials.gov, identifier NCT04608331.

Beyond bedwetting: How successful treatment is observed in sleep macrostructure

IntroductionSleep enuresis (SE), commonly known as bedwetting, refers to involuntary urination during sleep. It is a prevalent condition affecting approximately 15 % of children at age 5, 10 % by age 7, and 5 % by age 10. This condition can significantly impact both children and their families. The pathophysiology of SE is complex and not yet fully understood. There are several established treatment methods, but limited information on their sleep dynamics. ObjectiveThis study aimed to evaluate differences in sleep structure before and after treatment in patients with monosymptomatic SE (MSE), focusing on alarm therapy, desmopressin, and a combination of both. The analysis compared pre- and post-treatment differences within each treatment arm. The analysis was conducted for both successful and unsuccessful treatment outcomes. Methods/resultsThis was a prospective study with MSE patients, aged 6–16 years, diagnosed by multidisciplinary assessment. Of the 140 initial applicants 75 were initially included in the study and randomized for therapeutic intervention in three treatment arms, namely: alarm, desmopressin and alarm + desmopressin. Therapeutic response was evaluated 12 months after treatment discontinuation. Polysomnographic evaluation pre and post treatment was carried out. 51/75 completed the entire protocol. 42/51 were successfully treated and had a median age of 10 [8–12] and the non-success, 8 [7–10]. Among the successful patients, the percentage of N2 sleep decreased from a median of 55.7 %–48.5 % (p = 0.0004) in the alarm arm, from 58.8 % to 50 % (p = 0.002) in the desmopressin arm, and from 54.7 % to 50.9 % (p = 0.044) in the combined arm. The percentage of N3 sleep increased from 25.7 % to 30.1 % (p = 0.004) in the alarm arm, from 21.6 % to 26 % (p = 0.032) in the desmopressin arm, and from 23.7 % to 28.3 % (p = 0.014) in the combined arm. The arousal index significantly increased from pre-to post-treatment in all arms: in the alarm arm, from 1.25 to 2.8 (p = 0.002); in the desmopressin arm, from 1.3 to 2.7 (p = 0.019); and in the combined treatment arm, from 1 to 4 (p = 0.003). No significant differences were observed in the non-successful arm or among those who experienced complete resolution of the enuresis without treatment. ConclusionThe observed increase in N3 sleep and arousal and decrease in N2 sleep following successful treatment, regardless of the specific interventions, underscores the role of sleep in the pathophysiology of enuresis. Conversely, the lack of sleep differences in the non-successful arm further highlights the importance of sleep, beyond developmental factors, in influencing the clinical outcomes of enuresis, especially since all children were assessed 12 months after the start of treatment.

Lack variation of low slow-wave activity over time in the frontal region in NREM sleep may be associated with dyskinesia in Parkinson's disease.

Levodopa-induced dyskinesia (DYS) adversely affects the quality of life of Parkinson's disease (PD) patients. However, few studies have focused on the relationship between DYS and sleep and electroencephalography (EEG). Our study aimed to establish the objective physiological indicators assessed by polysomnography (PSG) that are associated with DYS in PD patients. We enrolled 122 patients with PD, divided into two groups: PD with DYS (n = 27) and PD without DYS group (non-DYS, n = 95). The demographics and clinical characteristics and sleep assessment in the two groups were collected. More importantly, overnight six-channel PSG parameters were compared in the two groups. We also compared different bands and brain regions of average power spectral density within each group. Compared with the non-DYS group, the DYS group tended to have a significantly higher percentage of nonrapid eye movement sleep (NREM). Gender, levodopa equivalent daily dose (LEDD), rapid eye movement (REM) sleep (min), and the NREM percentage were positively correlated with the occurrence of DYS. After adjusting for gender, disease duration, LEDD, taking amantadine or not, and Montreal Cognitive Assessment (MoCA), NREM%, N3%, and REM (min), the percentage of NREM sleep (p = 0.035), female (p = 0.002), and LEDD (p = 0.005), and REM sleep time (min) (p = 0.012) were still associated with DYS. There was no significant difference in whole-night different bands of average power spectral density between two groups. There was no significant difference in normalized average power spectral density of slow wave activity (SWA) (0.5-2 Hz, 0.5-4 Hz, and 2-4 Hz) of early and late NREM sleep in the DYS group. Dynamic normalized average power spectral density of SWA of low-frequency (0.5-2 Hz) reduction in the frontal region (p = 0.013) was associated with DYS in logistic regression after adjusting for confounding factors. PD patients with DYS have substantial sleep structure variations. Higher NREM percentage and less REM percentage were observed in PD patients with DYS. Dynamic normalized average power spectral density of low-frequency (0.5-2 Hz) SWA reduction in the frontal area could be a new electrophysiological marker of DYS in PD.

Novel and reappraised wide-band EEG findings in migraineurs: its correlation with several clinical variables

ObjectiveCortical spreading depolarization is one possible pathogenesis of migraine, of which slow neurophysiological change is barely recorded in conventional EEG settings. Using wide-band EEG conditions, we reappraised the features of EEG in migraineurs, including subdelta-band EEG changes. MethodsThis retrospective study included 144 patients with migraine. We delineated EEG of focal delta slow (FDS) (1-4 Hz) by time constant (TC) 0.3 s and focal subdelta slow (FSDS) (< 1 Hz) by TC 2 s. Relationships between clinical variables and EEG findings were evaluated. ResultsOf 144 patients, 39 had aura and 105 did not. FSDS and FDS were observed in 38 and 58 patients, respectively. No EEG was recorded during the aura. In multivariate analysis with the phase of migraine, family history, age, and percentage of sleep during EEG recording, the phase of migraine was related to the occurrence of FSDS (postdrome vs interictal, prodrome, and headache respectively (OR = 49.00 [95% CI = 3.89-616.66], 46.28 [2.99-715.78], 32.79 [2.23-481.96], p = 0.0026, 0.0061, 0.011). FDS was clinically unremarkable for differential evaluation. ConclusionsWide-band EEG abnormality in migraineurs, i.e., FSDS, can be affected by migraine phase. SignificanceWide-band EEG finding could be a biomarker related to clinical variables in migraines.

Sleep dysfunction and gut dysbiosis related amino acids metabolism disorders in cynomolgus monkeys after middle cerebral artery occlusion

IntroductionThis study aimed to explore the characteristics of post-stroke sleep dysfunction and verify their association with gut dysbiosis and the related amino acid metabolism disorders. This was achieved by using fecal microbiota transplantation (FMT) in a non-human primate stroke model. MethodsTwenty adult male cynomolgus monkeys were divided into the sham (n = 4), middle cerebral artery occlusion (MCAO, n = 5), MCAO + FMT (n = 3), and donor (n = 8) groups. The MCAO+FMT group received FMT at post-MCAO week 4. Sleep parameters, gut microbiota, gamma-aminobutyric acid (GABA), and glutamine (Gln) in the cerebrospinal fluid (CSF) were measured at baseline and postoperative weeks 4, 8, and 12. ResultsAt postoperative weeks 4, 8, and 12, the MCAO group showed decreased sleep efficiency, measured as the percentage of sleep during the whole night (82.3 ± 3.2 % vs 91.3 ± 2.5 %, 79.0 ± 3.75 % vs 90.8 ± 3.2 %, and 69.5 ± 4.8 % vs 90.5 ± 2.7 %; all P < 0.05), lower relative abundance of Lactobacillus (all P < 0.05), and reduced GABA concentrations in the CSF (317.3 ± 30.6 nmol/L vs 437.7 ± 25.6 nmol/L, 303.1 ± 48.9 nmol/L vs 4 40.9 ± 37.8 nmol/L, and 337.9 ± 49.4 nmol/L vs 457.4 ± 39.2 nmol/L; all P < 0.05) compared with the sham group. Sleep efficiency at post-FMT weeks 4 and 8 (84.7 ± 1.1 % vs 79.0 ± 3.75 %, and 84.1 ± 2.0 % vs 69.5 ± 4.8 %; both P < 0.05) and GABA concentration in the CSF at post-FMT week 4 (403.1 ± 25.4 nmol/L vs 303.1 ± 48.9 nmol/L, P < 0.05) was higher in the MCAO+FMT group than in the MCAO group. ConclusionsPost-stroke sleep dysfunction in monkeys is characterized by impaired sleep coherence, associated with decreased levels of probiotics such as Lactobacillus, GABA, and Gln in the CSF and can be ameliorated using FMT.

The association between slow-wave sleep and choroid plexus calcifications in older adults. Results from the sleep disorders substudy of the Atahualpa Project cohort.

ObjectiveIt has been suggested that choroid plexus calcifications (CPC) may be associated with glymphatic system dysfunction and with disturbed slow-wave (N3) sleep. If this is the case, volumetric analysis of CPC could be used to estimate the functional ability of the glymphatic system. However, data on this association is limited. This study aims to assess the association between percentages of N3 sleep – used as a putative marker of glymphatic system activity – and the volume of CPC in older adults. Patients and methodsCommunity-dwelling individuals aged ≥60 years enrolled in the Atahualpa Project Cohort received head CTs (for automated determinations of CPC volume) and a single-night polysomnography (PSG) for quantification of N3 sleep percentages. Multivariate linear regression and non-parametric models were fitted to assess the association between these variables. ResultsA total of 125 older adults (median age: 65 years; 32 % males) were included. The mean percentage of N3 sleep was 12.4±9.1 %, and the mean volume of CPC was 655±345.3 µL. Non-parametric locally weighted scatterplot smoothing showed that the volume of CPC increased as the percentage of N3 sleep increased, but only when N3 sleep is reduced (up to 12 % of total sleep time). The significance disappeared when PSG parameters were included in the model as well as in participants with normal N3 sleep percentages. ConclusionsStudy results suggest that in the presence of severe reductions in N3 sleep, increased CPC volume may be a manifestation of choroid plexus compensation or adaptation, and not necessarily dysfunction.

Sleep characteristics during the first year postpartum in a cohort of Black and White women

Study objectivesThe postpartum period is a unique time when sleep deficiency often occurs. Black and White adults are reported to have differences in sleep characteristics, but little is known if these differences exist in the postpartum period. Therefore, the purpose of this study was to examine sleep characteristics in a cohort of Black and White women from 6-8 weeks to 12 months postpartum. MethodsParticipants were 49 Black and 85 White women who gave birth to an infant at ≥37 weeks gestation. Participants were instructed to wear an Actiwatch for 7 days at 6-8 weeks, 4, 6, 9, and 12 months postpartum. Mixed-effects linear models with a race by time interaction were used to examine if characteristics differed between races over time. ResultsOnly bedtime varied by race. White women had a later bedtime at 6-8 weeks compared to 6 months, but no significant change occurred for Black women. For the entire sample, average nighttime sleep duration increased from 385 min at 6-8 weeks to 404 min at 4 months postpartum. Percent sleep during the sleep interval and wake after sleep onset (WASO) improved by 6 and 9 months, respectively. However, average WASO remained >45 min and sleep efficiency <85 % at all timepoints for both Black and White women. Compared to White women, Black women had significantly shorter sleep duration (range: 40.6-59.9 min shorter across all timepoints, p < 0.0001) and time in bed (range: 17.5-67.6 minutes shorter, p = 0.0046), and lower percent sleep (range: 0.7-1.2 % lower, p = 0.0407) and sleep efficiency (range: 2.6-5.7 % lower, p = 0.0005). Sociodemographic factors were associated with sleep outcomes in Black and White women while behavioral factors were associated with sleep outcomes in White women only. ConclusionWhile there were improvements in nighttime sleep duration and quality, sleep duration remained suboptimal, and quality remained poor throughout the first year postpartum. In this sample, differences existed in factors associated with sleep outcomes between Black and White women.

Effects of acoustic environment on sleep and mental health in residential regions near railways

Noise is an important environmental risk factor for physical and mental health. Furthermore, long-term noise exposure is burdensome for the mind and body and has become a serious problem. Rail transportation is one of the main methods used to transport goods in China; however, the noise and vibrations generated by freight trains have serious impacts on residents in nearby regions. To further investigate the relationship between railway noise and road noise exposure and changes in sleep duration and mental health scores, a field study in Harbin, China, was conducted and a health risk prediction model was constructed. The results showed that for every 1 dB increase in the Equivalent continuous A-weighted sound pressure level (LAeq), the percentage of deep sleep among residents living near the railway decreased by 0.2 %. Although residents near the railway reported similar sleep evaluations compared to those living farther away, they exhibited poorer mental health. Cox risk modeling indicates that the risk of mental health problems is approximately three times higher for those living near the railway. These findings potentially provide benefits in developing strategies to reduce the risk of mental illness for people residing near railways.

The effects of bedroom microclimate regulation behaviors on sleep quality: A field study on the Qinghai-Tibetan Plateau

The environmental regulatory behaviors of humans have a myriad of effects on the microclimate of bedrooms and the quality of sleep. Due to the special geographical climate, proposing non-invasive optimal strategies for environmental regulation is of considerable significance to improve sleep quality among high-altitude residents. However, there is no report on the environmental regulatory behaviors of residents at high-altitudes. Conducted in the Qinghai-Tibet Plateau at an altitude of 3255m, this study investigated the environmental regulatory behaviors, bedroom microclimate, and sleep quality of 355 local residents over the course of one week, and analyzed the influence of the behaviors on the bedroom environment and sleep quality. Results from 1462 nights of monitoring revealed that residents of the Qinghai-Tibet Plateau prefer to sleep with doors or windows open in both winter and summer. Leaving the doors or windows open during summer led to a reduction in sleep time, rapid eye movement sleep and awakening time, which is the most prominent sleep issue at high-altitude, while in winter the percentage of deep sleep decreased with open doors or windows. The habit of humidification displayed a noticeable seasonal bias, with plateau residents being more inclined to adopt humidification measures in winter. Based on the results, this study recommends sleeping with doors or windows open without humidification in summer, while in the winter, humidification is necessary.

The relationship between rapid eye movement electromyogram activity and sleep stability in rapid eye movement sleep behavior disorder

Objective: To investigate the relationship between the types of electromyogram (EMG) activity and sleep stability during rapid eye movement (REM) in patients with rapid eye movement sleep behavior disorder(RBD). Methods: One hundred and three patients with RBD who met the inclusion and exclusion criteria at the Second Affiliated Hospital of Air Force Military Medical University from January 2017 to December 2019 were retrospectively analyzed. The general situation, clinical symptoms, sleep and emotion questionnaires and nocturnal PSG data were collected. According to the different proportions of tonic and phasic EMG activity, the group with a higher proportion of tonic EMG than phasic EMG was defined as the tonic dominant group, and the group with a higher proportion of phasic EMG than tonic was defined as the phasic dominant group. The sleep instability index was calculated according to the ratio of the number of transitions from sleep to wakefulness to the total sleep time of each sleep stage. Multiple linear regression was used to explore the relationship between REM EMG activity and sleep instability index. Results: A total of 35 idiopathic RBD (iRBD) patients were included, aged(54.5±18.2)years, with 17 males and 18 females. There were 27 RBD with Parkinson's disease (PD), with an average age of (59.4±7.9)years, including 17 males and 10 females. Additionally, there were 41 RBD patients with narcolepsy, aged (21.2±13.2)years, consisting of 22 males and 19 females. Both iRBD and RBD patients with PD had lower objective total sleep time, sleep latency, sleep efficiency, wake time after sleep onset and the percentage of N3 sleep compared to RBD with episodic sleep disorder (all P<0.05). N1-W index[M(Q1, Q3),10.6 (6.5, 16.9)/h vs 7.3 (4.7, 10.5)/h], N2-W index [4.0 (2.2, 5.6)/h vs 2.3 (1.5, 3.9)/h], NREM-W index [ (5.8±2.9)/h vs (4.5±3.2)/h] and REM-W index[ 3.9 (1.9, 7.3)/h vs 2.7 (1.0, 4.0)/h] in the phasic dominant group were higher than those in the tonic dominant group. After adjusting for confounding factors, the effect of phasic EMG dominant group on REM-W was higher than that in the tonic dominant group (β=2.05, 95%CI: 0.09-3.26, P=0.012). Conclusion: In RBD patients, the phasic EMG activity has a significant impact on sleep stability, especially on REM sleep stability.

Changes in slow-wave sleep characteristics in Parkinson's disease patients with mild-moderate depression

IntroductionDepression and sleep disturbances are commonly seen non-motor symptoms in patients with Parkinson's disease (PD). This study used polysomnography to examine the relationship between mild-moderate depression in PD and sleep characteristics, particularly slow wave activities (SWA). Methods59 PD patients were split into two groups: nd-PD (n = 27) (patients with PD without depression) and d-PD (n = 32) (patients with PD with mild-moderate depression). Their clinical features, polysomnography parameters, and demographics were evaluated. Early and late sleep SWA spectrum densities and overnight SWA decline in different brain regions were particularly analyzed. ResultsNon-rapid eye movement 3 (N3) sleep duration and percentage were greater in the d-PD group. N3 percentage was linked to depression (p = 0.014). During late sleep, higher SWA (0.5–4Hz) in the frontal and central regions, higher low-SWA (0.5–2Hz) in the whole brain, central and occipital regions, and higher high-SWA (2–4Hz) in the frontal region was observed in the d-PD group. During early sleep, there was also higher low-SWA (0.5–2Hz) in the occipital region. Patients in d-PD group exhibited reduced overnight high-SWA (2–4Hz) decline (Δhigh-SWA) in the whole brain and occipital regions. Δhigh-SWA(2–4Hz) in the occipital region were associated with depression (p = 0.049). ConclusionPD patients with mild-moderate depression have impaired slow wave sleep, exhibiting as increased N3 sleep, SWA, and reduced overnight SWA decline. This implies that synaptic strength reduction during sleep and impaired synaptic homeostasis regulation may be associated with depression in PD. Reduced overnight high-SWA decline in the occipital region may serve as a novel electrophysiological biomarker for indicating depression in PD.

Nocturnal hypoxemic burden in patients with heart failure: Emerging prognostic role of its nonspecific component

BackgroundNocturnal hypoxemic burden has been shown to be a robust, independent predictor of all-cause mortality in patients with heart failure and reduced ejection fraction (HFrEF) and to occur in a severe form even in patients with low or negligible frequency of respiratory events (apneas/hypopneas). This suggests the existence of two components of hypoxemic burden: one unrelated to respiratory events and the other related. The aim of this study was to characterize these two components and to evaluate their prognostic value. MethodsNocturnal hypoxemic burden was assessed in a cohort of 280 patients with HFrEF by measuring the percentage of sleep with an oxygen saturation (SpO2) <90% (T90), and the area of the SpO2 curve below 90% (Area90). Both indices were also recalculated within the sleep segments associated with respiratory events (event-related component: T90Eve, Area90Eve) and outside these segments (nonspecific component: T90Nspec, Area90Nspec). The outcome of the survival analysis (Cox regression) was all-cause mortality. ResultsDuring a median follow-up of 60 months, 87 patients died. T90, Area90, and their components were significant in univariate analysis (P < .05 all). However, when these indices were adjusted for known risk factors, T90, T90Nspec, Area90, and Area90Nspec remained statistically significant (P = .018, hazard ratio (HR)=1.12, 95%CI=(1.02, 1.23); P = .007, HR=1.20, 95% CI = [1.05, 1.37]; P = .020, HR = 1.05, 95% CI = [1.01, 1.10]; P = .0006, HR = 1.15, 95% CI = [1.06, 1.25]), whereas T90Eve and Area90Eve did not (P = .27, P = .28). These results were internally validated using bootstrap resampling. ConclusionsBy demonstrating a significant independent association of nonspecific hypoxemic burden with all-cause mortality, this study suggests that this component of total nocturnal hypoxemic burden may play an important prognostic role in patients with HFrEF.

Objective sleep enhancement in Parkinson's disease: A sham-controlled trial of low-frequency repetitive transcranial magnetic stimulation over the right dorsolateral prefrontal cortex

IntroductionParkinson's disease (PD) is often accompanied by sleep disturbances, impacting patients' quality of life. While repetitive transcranial magnetic stimulation (rTMS) shows promise in improving self-reported sleep quality, its effects on objective sleep architecture in PD remain understudied. Sleep disturbances, including rapid eye movement (REM) and slow-wave sleep disturbances, correlate with cognitive decline and motor symptoms. This study investigated the effect of low-frequency rTMS targeting the right dorsolateral prefrontal cortex (DLPFC) modifying objective sleep architecture and explored symptom improvement mechanisms in PD patients. MethodsIn this randomized, double-blind, sham-controlled trial, 67 PD patients received 10 consecutive days of 1-Hz rTMS over the right DLPFC. Polysomnography assessed sleep microstructure, while electroencephalogram recordings evaluated power spectral density and sleep spindle activity. Clinical scales measured sleep quality, motor symptoms, and cognition at baseline, post-treatment, and 3 months post-rTMS. ResultsThe rTMS group exhibited improvements in sleep quality, motor symptoms, and cognition post-treatment, persisting at the 3-month follow-up. There was a notable increase in the REM sleep proportion post-rTMS. The rTMS group exhibited elevated low-frequency (0.5–2 Hz) slow-wave electroencephalogram spectral density during non-REM sleep. Cognitive enhancement correlated with increased lower delta power, while motor symptom progression correlated with spindle frequency and slow-wave sleep percentage changes. ConclusionLow-frequency rTMS targeting the right DLPFC holds promise for improving clinical symptoms and modulating sleep architecture in PD. These findings suggest a link between symptom improvement and sleep structure enhancement, highlighting the need for further investigation into the therapeutic potential of rTMS in PD management.

The stability of slow-wave sleep and EEG oscillations across two consecutive nights of laboratory polysomnography in cognitively normal older adults.

Laboratory polysomnography provides gold-standard measures of sleep physiology, but multi-night investigations are resource intensive. We assessed the night-to-night stability via reproducibility metrics for sleep macrostructure and electroencephalography oscillations in a group of cognitively normal adults attending two consecutive polysomnographies. Electroencephalographies were analysed using an automatic algorithm for detection of slow-wave activity, spindle and K-complex densities. Average differences between nights for sleep macrostructure, electroencephalography oscillations and sleep apnea severity were assessed, and test-retest reliability was determined using two-way intraclass correlations. Agreement was calculated using the smallest real differences between nights for all measures. Night 2 polysomnographies showed significantly greater time in bed, total sleep time (6.3 hr versus 6.8 hr, p < 0.001) and percentage of rapid eye movement sleep (17.5 versus 19.7, p < 0.001). Intraclass correlations were low for total sleep time, percentage of rapid eye movement sleep and sleep efficiency, moderate for percentage of slow-wave sleep and percentage of non-rapid eye movement 2 sleep, good for slow-wave activity and K-complex densities, and excellent for spindles and apnea-hypopnea index with hypopneas defined according to 4% oxygen desaturation criteria only. The smallest real difference values were proportionally high for most sleep macrostructure measures, indicating moderate agreement, and proportionally lower for most electroencephalography microstructure variables. Slow waves, K-complexes, spindles and apnea severity indices are highly reproducible across two consecutive nights of polysomnography. In contrast, sleep macrostructure measures all demonstrated poor reproducibility as indicated by low intraclass correlation values and moderate agreement. Although there were average differences in percentage of rapid eye movement sleep and total sleep time, these were numerically small and perhaps functionally or clinically less significant. One night of in-laboratory polysomnography is enough to provide stable, reproducible estimates of an individual's sleep concerning measures of slow-wave activity, spindles, K-complex densities and apnea severity.