Effects of an individualized exercise training program on severity markers of obstructive sleep apnea syndrome: a randomised controlled trial

ObjectiveObstructive sleep apnea (OSA) is a high prevalent disorder with severe consequences including sleepiness, metabolic, and cardiovascular disorders. The aim of this study was to assess the effect of an individualized exercise-training (IET) program with educational sessions vs educational sessions alone on severity markers of OSA over an eight-week duration.MethodsThis was a randomised, controlled, parallel-design study. In sum, 64 patients with moderate-to-severe OSA (apnea-hypopnea index AHI 15–45/hour), low physical activity level (Voorrips<9), body-mass index (BMI) <40 kg/m² were included in intervention group (IG) or control group (CG), and 54 patients finished the study. All underwent polysomnography (PSG), multiple sleep latency test (MSLT), constant workload exercise test, blood samples and fulfilled questionnaires twice. The primary endpoint was the change in apnea-hypopnea (AHI) at eight weeks from baseline. Main secondary endpoints were daytime sleepiness assessed by questionnaire and objective tests.ResultsNo significant between-group differences were found for changes in AHI. A reduction in AHI was found in IG only (p = 0.005). Compared to CG, exercise training leads to a greater decrease in AHI during REM sleep (p = 0.0004), with a significant increase in mean daytime sleep latency (p = 0.02). Between-group differences were significant for weight reduction, severity of fatigue, insomnia and depressive symptoms with trend for sleepiness symptoms.ConclusionsIn adult patients with moderate-to-severe OSA, IET did not decrease AHI compared to the control group but improved markers of severity of OSA, in particular AHI in rapid eye movement (REM) sleep and objective daytime sleepiness. Adding personalized exercise training to the management of patients with OSA should be considered.ClinicalTrials.gov identifierNCT01256307.     

QT interval variability index and QT interval duration during different sleep stages in patients with obstructive sleep apnea

ObjectivesThe aim of the study was to investigate the impact of obstructive sleep apnea (OSA) on the QT interval variability and duration in patients during different sleep stages.MethodsPolysomnographic recordings of 28 (13 male, 15 female) patients with OSA and 30 (15 male, 15 female) patients without OSA were analyzed. The QT interval variability index (QTVI) and the corrected QT interval (QTc) analyses were performed using two awake, 3–4 non-rapid eye movement (NREM) and three rapid eye movement (REM) sleep episodes (each 300 s). The Bazett formula, linear, and parabolic heart rate correction formulas with two separate α values were used.ResultsQTVI was statistically higher in OSA than in non-OSA patients for males while awake (awake −0.7 ± 0.3 vs −1.2 ± 0.2, p = 0.001; NREM ‒0.9 ± 0.4 vs −1.1 ± 0.3, p = 0.110; REM ‒1.1 ± 0.3 vs −1.3 ± 0.2, p = 0.667) and for females in all wake–sleep stages (awake −0.3 ± 0.7 vs −0.9 ± 0.5, p = 0.001; NREM ‒0.3 ± 0.5 vs −0.8 ± 0.4, p = 0.002; REM −0.3 ± 0.5 vs −1.0 ± 0.4, p < 0.001). QTVI was significantly higher during awake compared to sleep stages in OSA males (p < 0.05); no difference between wake–sleep stages was found in females (p > 0.05). Significant gender differences in QTVI existed in OSA patients during sleep (p < 0.05) but not while awake. No significant differences in QTc between patients groups were observed.ConclusionsOSA is associated with increased QT variability. REM sleep per se does not increase QTVI. In OSA patients, QTVI might be a more useful measure to detect ventricular repolarization abnormality than measures of QTc.     

Severity of individual obstruction events increases with age in patients with obstructive sleep apnea

BackgroundAge is a risk factor of obstructive sleep apnea (OSA). It has been shown that OSA progresses over time, although conflicting results have been reported. However, the effect of age on the severity of OSA and individual obstruction events has not been investigated within different OSA severity categories by taking the most prominent confounding factors (i.e., body mass index, gender, smoking, daytime sleepiness, snoring, hypertension, heart failure, and proportion of supine sleep) into account.MethodsPolygraphic data of 1090 patients with apnea–hypopnea index (AHI) ≥5 were retrospectively reanalyzed. The effect of age on the severity of OSA and obstruction events was investigated in general, within different OSA severity categories, and in different age groups (age <40, 40≤ age <50, 50≤ age <60, and age ≥60 years).ResultsIn the whole population, AHI and durations of apneas, hypopneas, and desaturations increased with increasing age (B ≥ 0.108, p ≤ 0.010). In more detailed analysis, AHI increased with age only in the moderate OSA category (B = 0.075, p = 0.022), although durations of apneas increased in mild and severe OSA categories (B ≥ 0.076, p ≤ 0.038). Furthermore, durations of hypopneas increased with age in mild and moderate OSA categories (B ≥ 0.105, p ≤ 0.038), and durations of desaturations (B ≥ 0.120, p ≤ 0.013) in all OSA severity categories. AHI was not statistically significantly different between the age groups, although durations of obstruction events tended to increase towards older age groups.ConclusionAs obstruction event severity was more strongly dependent on the age than it was dependent on AHI, considering the severity of obstruction events could be beneficial while estimating the long-term effects of the treatments and prognosticating the disease progression.     

Clinical characteristics of sleep apnea in middle-old and oldest-old inpatients: symptoms and comorbidities

BackgroundObstructive sleep apnea (OSA) is prevalent in older adults but still underdiagnosed for many reasons, such as underreported symptoms, non-specific ones because of the comorbidities and polypharmacy, or the social belief of sleep problems as normal with aging.ObjectivesTo identify salient symptoms and comorbidities associated with OSA, diagnosed by nocturnal respiratory polygraphy in geriatric inpatients.MethodWe conducted a retrospective, cross-sectional study in a sample of 102 geriatric inpatients from a French Geriatric University Hospital. We reviewed medical records to collect demographic, medical information including comorbidities, the geriatric cumulative illness rating scale (CIRS-G), subjective sleep-related symptoms and data of overnight level three portable sleep polygraphy recording.ResultsAmong classic OSA symptoms, only excessive daytime sleepiness (p = 0.02) and nocturnal choking (p = 0.03) were more prevalent in older inpatients with OSA (n = 64) than in those without (n = 38). The prevalence of comorbidities and mean CIRS-G scores were not different between groups except for the lower prevalence of chronic obstructive pulmonary disease and the higher level of creatinine clearance in OSA patients. Multivariate analysis showed OSA was associated with excessive daytime sleepiness (OR = 2.83, p = 0.02) in symptoms-related model and with composite CIRS-G score (OR 1.26, p = 0.04) in comorbidities-related model.ConclusionsOnly excessive daytime sleepiness and comorbidity severity (composite CIRS-G score) were associated with the objective diagnosis of OSA, while other usual clinical OSA symptoms and comorbidities in geriatric inpatients were not. These findings emphasize the importance of excessive daytime sleepiness symptom, when reported in comorbid older patients, strongly suggesting OSA and requiring adequate nocturnal exploration.     

Sex Differences in Excessive Daytime Sleepiness Among Patients With Obstructive Sleep Apnea

Background and PurposeTo identify sex differences in daytime sleepiness associated with apnea severity and periodic limb movements during sleep (PLMS) in subjects with obstructive sleep apnea (OSA).MethodsThis study used the Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and Sleep Hygiene Index (SHI) in logistic regression analyses with interaction terms. Severe OSA, excessive daytime sleepiness (EDS), and PLMS were defined as an apnea-hypopnea index of ≥30, an ESS score of ≥11, and a periodic limb movements index of >15, respectively.ResultsThe 1,624 subjects with OSA (males, 79.1%) comprised 45.3%, 38.2%, and 16.4% with severe OSA, EDS, and PLMS, respectively. Multiple logistic regression without interaction terms showed that sex, severe OSA, and PLMS were not significantly associated with EDS. However, significant interactions were noted between sex and severe OSA and PLMS in EDS in both crude and adjusted models (all p values<0.05). In the adjusted model, severe OSA was associated with EDS in males (p=0.009) but not in females. PLMS were more likely to be associated with EDS in females (p=0.013), whereas PLMS were less likely to be associated with EDS in males (p=0.041). The models were adjusted by the BDI score, SHI, and presence of medical comorbidities.ConclusionsThere are significant sex differences in subjective daytime sleepiness in subjects with severe OSA and PLMS. Severe OSA and PLMS may influence daytime sleepiness more in males and females, respectively.     

Rapid eye movement sleep disturbance in patients with refractory epilepsy: A polysomnographic study

Objective/BackgroundPatients with epilepsy have disrupted sleep architecture and a higher prevalence of sleep disturbance. Moreover, obstructive sleep apnea (OSA) is more common among patients with refractory epilepsy. Few studies have compared subjective sleep quality, sleep architecture, and prevalence of OSA between patients with refractory epilepsy and those with medically controlled epilepsy. Therefore, this study aimed to evaluate the differences in sleep quality, sleep architecture, and prevalence of OSA between patients with refractory epilepsy and patients with medically controlled epilepsy.PatientsThis retrospective case–control study included 38 patients with refractory epilepsy and 96 patients with medically controlled epilepsy. Sleep parameters and indices of sleep-related breathing disorders were recorded by standard in-laboratory polysomnography. The scores from sleep questionnaires on sleep quality and daytime sleepiness were compared between the two groups.ResultsPatients with refractory epilepsy versus medically controlled epilepsy had statistically significantly decreased rapid eye movement (REM) sleep (13.5 ± 6.1% vs. 16.2 ± 6.1%) and longer REM latency (152.2 ± 84.1 min vs. 117.2 ± 61.9 min). Further, no differences were found in the prevalence of sleep-related breathing disorders, subjective sleep quality, prevalence of daytime sleepiness, and quality of life. Although not statistically significant, patients with refractory epilepsy have a lower rate of OSA compared with those with medically controlled epilepsy (21.1% vs. 30.2%).ConclusionsPatients with refractory epilepsy had more disrupted REM sleep regulation than those with medically controlled epilepsy. Although patients with epilepsy have a higher risk of OSA, in this study patients with refractory epilepsy were not susceptible to OSA.     

Power spectral densities of nocturnal pulse oximetry signals differ in OSA patients with and without daytime sleepiness

BackgroundAs nocturnal hypoxemia and heart rate variability are associated with excessive daytime sleepiness (EDS) related to OSA, we hypothesize that the power spectral densities (PSD) of nocturnal pulse oximetry signals could be utilized in the assessment of EDS. Thus, we aimed to investigate if PSDs contain features that are related to EDS and whether a convolutional neural network (CNN) could detect patients with EDS using self-learned PSD features.MethodsA total of 915 OSA patients who had undergone polysomnography with multiple sleep latency test on the following day were investigated. PSDs for nocturnal blood oxygen saturation (SpO₂), heart rate (HR), and photoplethysmogram (PPG), as well as power in the 15–35 mHz band in SpO₂ (P_SPO2) and HR (P_HR), were computed. Differences in PSD features were investigated between EDS groups. Additionally, a CNN classifier was developed for identifying severe EDS patients based on spectral data.ResultsSpO₂ power content increased significantly (p < 0.002) with increasing severity of EDS. Furthermore, a significant (p < 0.001) increase in HR-PSD was found in severe EDS (mean sleep latency < 5 min). Elevated odds of having severe EDS was found in P_SPO2 (OR = 1.19–1.29) and P_HR (OR = 1.81–1.83). Despite these significant spectral differences, the CNN classifier reached only moderate sensitivity (49.5%) alongside high specificity (80.4%) in identifying patients with severe EDS.ConclusionsWe conclude that PSDs of nocturnal pulse oximetry signals contain features significantly associated with OSA-related EDS. However, CNN-based identification of patients with EDS is challenging via pulse oximetry.     

The relationships between improvements in daytime sleepiness,fatigue and depression and psychomotor vigilance task testing with CPAP use in patients with obstructive sleep apnea

ObjectiveThe purpose of this study was to determine if the subjective improvements in daytime sleepiness, fatigue and depression experienced by patients with obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) therapy predict an objective improvement in vigilance, and whether patients with mild-to-moderate OSA differ from patients with severe OSA in this regard.MethodsA total of 182 patients underwent psychomotor vigilance task (PVT) testing and measurements of subjective daytime sleepiness, fatigue and depression at baseline and after a minimum of one month of adherent CPAP use at an adequate pressure.ResultsPatients with both mild-to-moderate (n = 92) and severe (n = 90) OSA experienced improvements in subjective daytime sleepiness, fatigue and depression, but objective improvement in vigilance was only seen in patients with severe OSA. In patients with severe OSA, while a correlation was found between improvements in daytime sleepiness and some PVT parameters, changes in subjective daytime sleepiness, fatigue and depression scores were not predictive of objective improvement in vigilance while controlling for all these subjective symptoms and for age, gender, body mass index, apnea-hypopnea index/respiratory event index and total sleep time/total recording time with pulse oximetry below 90%.ConclusionsWe found no predictive relationship between subjective improvements in daytime sleepiness, fatigue and depression and objective vigilance with CPAP use in patients with OSA. These results suggest that subjective complaints of daytime impairment and objective measures of vigilance in patients with OSA should be assessed separately while evaluating the efficacy of CPAP therapy on daytime functioning.     

The effect of childhood obstructive sleep apnea on ambulatory blood pressure is modulated by the distribution of respiratory events during rapid eye movement and nonrapid eye movement sleep

ObjectiveWe aimed to investigate if different childhood obstructive sleep apnea (OSA) subtypes, namely rapid eye movement (REM)-related, nonrapid eye movement (NREM)-related and stage-independent OSA would exert different effects on ambulatory blood pressure (ABP).MethodsData from our previous school-based cross-sectional study were reanalyzed. Subjects who had an obstructive apnea–hypopnea index (OAHI) between 1 and 10 events per hour and a total REM sleep duration of >30 min were included in our analysis. REM-related and NREM-related OSA were defined as a ratio of OAHI in REM sleep (OAHI_REM) to OAHI in NREM sleep (OAHI_NREM) of >2 and <0.5, respectively. The others were classified as stage-independent OSA.ResultsA total of 162 subjects were included in the analysis. In the mild OSA (OAHI, 1–5 events/h) subgroup, no significant differences in any ABP parameters were found between OSA subtypes. On the other hand, in subjects with moderate OSA (OAHI, 5–10 events/h), the REM-related OSA subtype had a significantly lower daytime systolic blood pressure (SBP) z score (−0.13 ± 0.90 cf 1.15 ± 0.67; P = .012) and nighttime SBP z score (0.29 ± 1.06 cf 1.48 ± 0.88, P = .039) than the stage-independent OSA subtype. Linear regression analyses revealed that OAHI_NREM but not OAHI_REM was significantly associated with both daytime (P = .008) and nighttime SBP (P = .042) after controlling for age, gender, and body size.ConclusionChildren with obstructive events mainly in REM sleep may have less cardiovascular complications than those with stage-independent OSA.     

The relationship between weight change and daytime sleepiness: the Sleep Heart Health Study

ObjectiveThrough a causal framework, we aim to assess the association between weight change and daytime sleepiness, and the role of obstructive sleep apnoea (OSA) in this relationship.MethodsFrom the Sleep Heart Health Study, we selected individuals who were: (1) 40–64 years old, with (2) body mass index (BMI) ≥18.5 kg/m², (3) no history of stroke, treatment for OSA, and tracheostomy at baseline. We used multiple linear regression to assess the relationship between five-year weight change and daytime sleepiness (assessed through Epworth Sleepiness Scale (ESS)) at five years, adjusting for daytime sleepiness, demographics, diabetes, subjective sleep duration, sleep disturbance, smoking status, weight, and use of antidepressants and benzodiazepines at baseline, in those with complete data (N = 1468). We further assessed the potential mediating role of OSA in this relationship.ResultsAt baseline, the study participants were on average 55 years old, 46% males, with mean BMI 28 kg/m²; and 25% had ESS>10. ESS at five years worsened by 0.36 units (95% confidence interval (CI) 0.12–0.61, p = 0.004) with every 10-kg weight gain. When stratified by sex, this relationship was only found in women (0.55, 95% CI 0.25–0.86, p < 0.001; p-interaction = 0.02). Approximately one-fifth of the relationship between weight change and daytime sleepiness was mediated by severity of OSA at five years.ConclusionWeight gain has a detrimental effect on daytime sleepiness, mostly through pathways other than OSA. This study provides further evidence and understanding of the relationship between obesity and excessive daytime sleepiness.     

Cardiovascular consequences of obstructive sleep apnea in women: a historical cohort study

Objective/BackgroundEvidence on sex differences in the association between obstructive sleep apnea (OSA) and cardiovascular outcomes is limited and controversial. We conducted a historical cohort study to investigate this relationship.Patients/methodsClinical data on adults who underwent sleep study at a large urban academic hospital (Toronto, Canada) between 1994 and 2010 were linked to provincial health administrative data from 1991 to 2015. We fit Cox regressions to investigate the association between OSA severity and a cardiovascular composite outcome (all-cause mortality or hospitalization due to myocardial infarction, stroke, heart failure or atrial fibrillation), controlling for risk factors and stratifying by sex.ResultsA total of 10,149 subjects were included: median age of 49 years, 38% women. Over a median of 9.3 years, 1782 (18%) participants developed an outcome. The association between percentage of sleep time spent with oxygen saturation <90% and outcome was stronger for women (HR for IQR, 3 vs 0% = 1.30, 1.19–1.42) than for men (HR for IQR = 1.13, 1.06–1.21) (p for interaction = 0.01) in the adjusted model. Stratifying by sex, oxygen desaturations and heart rate in sleep were significant predictors in both men and women, while presence of daytime sleepiness, sleep efficiency and periodic leg movements in sleep were predictive in women but not in men.ConclusionsIn a large clinical cohort with suspected OSA, the impact of OSA as measured by the degree of nocturnal oxygen desaturation on the composite outcome was found to be greater in women than in men. We also found a different predictive ability of OSA-related factors by sex.     

Continuous positive airway pressure treatment and anxiety in adults with coronary artery disease and nonsleepy obstructive sleep apnea in the RICCADSA trial

BackgroundAnxiety and obstructive sleep apnea (OSA) coexist among adults with coronary artery disease (CAD) following revascularization. Continuous positive airway pressure (CPAP) is the first line treatment of OSA patients with daytime sleepiness. The current study evaluated the effect of CPAP on anxiety in CAD patients with nonsleepy OSA.MethodsTwo hundred forty-four revascularized CAD patients with nonsleepy OSA (apnea-hypopnea index ≥15/h, Epworth Sleepiness Scale score <10) were randomly assigned to CPAP or no-CPAP between 2005 and 2010. Zung Self-rating Anxiety Scale (SAS) was administered at baseline and after 3 and 12 months with higher scores suggesting more anxiety.ResultsA total of 208 patients with complete SAS scores at baseline and 12-month follow-up were included (CPAP, n = 103; no-CPAP, n = 105). In the intention-to-treat analysis, CPAP had no significant effect on the SAS scores. On-treatment analysis revealed a significant increase in the median of delta SAS score (+3.75) after three months among the participants using the device 2.8 h/day or more while there was a decline in the median of delta SAS score (−1.25) in the non-adherent or no-CPAP group (p = 0.031). The increase in the SAS score (+1.25) in the adherent group, and the decline (−1.25 points) in the non-adherent/no-CPAP group remained significant after one year (p = 0.011). Baseline SAS score predicted non-adherence [adjusted odds ratio 1.11; 95% confidence interval (CI) 1.04–1.18; p = 0.003], and there was an association between the increase in the SAS scores and accumulated CPAP hours/day [standardized β = 0.144 (95% CI 0.005–0.695), p = 0.047].ConclusionOur results suggest that anxiety should be considered in the management of CAD patients with nonsleepy OSA following revascularization.Clinical trial registrationNCT00519597.     

Efficacy and safety of solriamfetol for excessive sleepiness in narcolepsy and obstructive sleep apnea: findings from randomized controlled trials

BackgroundSolriamfetol is developed for the treatment of excessive sleepiness in adult patients with narcolepsy and obstructive sleep apnea (OSA). No systematic review of existing literature has been investigated before. Therefore, the meta-analysis is conducted to assess the efficacy and safety of solriamfetol for excessive sleepiness in narcolepsy and OSA.MethodsPubMed, Embase and Cochrane Library databases were searched from earliest date to July 2020 for randomized controlled trials (RCTs) and the primary outcomes were change from baseline in mean sleep latency and Epworth Sleepiness Scale (ESS).ResultsWe pooled 1177 patients from five RCTs and found solriamfetol led to a significant increment in mean sleep latency (MD = 9.52, 95% CI: 7.60 to 11.44, P < 0.00001) and a reduction in ESS score (MD = −3.74, 95% CI: −4.38 to −3.09, P < 0.00001) compared with placebo. The proportion of patients with at least one adverse event was significantly increased in solriamfetol group (RR = 1.42, 95% CI: 1.24 to 1.64, P < 0.00001), while no statistical differences existed in the risk of at least one serious adverse event between solriamfetol and controlled group (RR = 0.95, 95% CI: 0.24 to 3.77, P = 0.39).ConclusionsA dose of 150 mg solriamfetol is proved to be the appropriate and stable dose for excessive sleepiness. In addition, solriamfetol showed good efficacy for excessive sleepiness in narcolepsy and OSA but also significantly increases the risk of adverse events.     

The influence of sleep disordered breathing in REM sleep behavior disorder

Objectives/backgroundBecause both REM sleep behavior disorder (RBD) and Obstructive Sleep Apnea (OSA) can present with similar symptoms, it is important to understand the influence of OSA in the clinical manifestations of RBD and whether RBD modulates OSA severity. Our objectives were to compare: 1. the intensity of non-motor symptoms between RBD patients with (RBD-OSA) and without OSA (RBD-non-OSA), and 2. polysomnographic features between RBD-OSA and OSA without RBD (OSA-non-RBD) patients.Methods32 RBD cases were divided in two groups according to the presence of moderate to severe OSA [Apnea Hypopnea Index (AIH) > 14] (RBD-OSA vs. RBD-non-OSA). Non-motor symptoms were assessed with Montreal Cognitive Assessment Scale, SCOPA-Sleep and the Non-Motor Symptom Scale (NMSS) for Parkinson's disease. RBD-OSA patients were compared to 20 OSA-non-RBD patients matched for age, AHI and gender.ResultsCompared to RBD-non-OSA (n = 22) patients, RBD-OSA patients (n = 10) showed significantly higher scores in SCOPA-Sleep Daytime and NMSS Attention/Memory, Gastrointestinal and Urinary domains, as well as higher sleep fragmentation, more oxygen desaturation and higher AIH in NREM sleep. RBD-OSA patients presented with less O₂ desaturation, snoring, and BMI when compared to OSA-non-RBD patients.DiscussionOur data suggests that OSA contributes to hypersomnolence, gastro-intestinal, memory, and urinary complaints in RBD patients. RBD patients seem to have a milder OSA phenotype (possible reflecting a protective role conferred by the maintenance of muscle tone during REM sleep) and to be less prone to obesity and snoring than non-RBD patients.     

A new EEG biomarker of neurobehavioural impairment and sleepiness in sleep apnea patients and controls during extended wakefulness

ObjectiveTo explore the use of detrended fluctuation analysis (DFA) scaling exponent of the awake electroencephalogram (EEG) as a new alternative biomarker of neurobehavioural impairment and sleepiness in obstructive sleep apnea (OSA).MethodsEight patients with moderate–severe OSA and nine non-OSA controls underwent a 40-h extended wakefulness challenge with resting awake EEG, neurobehavioural performance (driving simulator and psychomotor vigilance task) and subjective sleepiness recorded every 2-h. The DFA scaling exponent and power spectra of the EEG were calculated at each time point and their correlation with sleepiness and performance were quantified.ResultsDFA scaling exponent and power spectra biomarkers significantly correlated with simultaneously tested performance and self-rated sleepiness across the testing period in OSA patients and controls. Baseline (8am) DFA scaling exponent but not power spectra were markers of impaired simulated driving after 24-h extended wakefulness in OSA (r = 0.738, p = 0.037). OSA patients had a higher scaling exponent and delta power during wakefulness than controls.ConclusionsThe DFA scaling exponent of the awake EEG performed as well as conventional power spectra as a marker of impaired performance and sleepiness resulting from sleep loss.SignificanceDFA may potentially identify patients at risk of neurobehavioural impairment and assess treatment effectiveness.     

Sleepiness and activity in heart failure patients with reduced ejection fraction and central sleep-disordered breathing

ObjectivePatients with heart failure (HF) and sleep disordered breathing (SDB) are typically not sleepy, unlike patients without heart failure. Previous work in HF patients with obstructive SDB suggested that sleepiness was associated with a reduction in daytime activity. The consequences of predominately central SDB on sleepiness in HF are less well understood. The aim of this study was to test the hypothesis that subjective sleepiness is associated with reduced daytime activity in HF patients with central SDB, compared to those without SDB.MethodsThe Epworth Sleepiness Scale (ESS), nocturnal polysomnography, and 14 days of wrist watch actigraphy were used to assess subjective daytime sleepiness, nocturnal sleep and breathing, and 24-h activity levels, respectively.ResultsA total of 54 patients with HF were studied, nine had obstructive SDB and were removed from further analysis. Of the patients, 23 had HF with predominantly central SDB (HF-CSA; apnea–hypopnea index (AHI) median 20.6 (IQR 12.9–40.2)/h), and 22 had noSDB (HF-noSDB; AHI 3.7 (2.5–5.9)/h). The median patient age was 68 years (range 59–73 years). There were no significant differences either in ESS score (HF-CSA; 8 [4–10] vs. HF-noSDB; 8 (6–12); p = 0.49) or in duration of daytime activity (HF-CSA 14.5 (14.1–15.2) and HF-noSDB 15.1 (14.4–15.3) hours; p = 0.10) between the groups.ConclusionHF patients with predominately central SDB are not subjectively sleepy compared to those without SDB, despite reduced sleep quality. We speculate that the lack of sleepiness (based on ESS score) may be due to increased sympathetic nerve activity, although further studies are needed due to the small number (n = 5) of sleepy HF-CSA patients. Daytime activity was not different between HF-noSDB and HF-CSA patients.     

Subjective nocturnal symptoms have different associations with depressive symptoms and anxiety than with daytime sleepiness in patients with obstructive sleep apnea

BackgroundWe determined the relationships among the subjective symptoms of sleep apnea and daytime sleepiness, depressive symptoms, and anxiety in adults with obstructive sleep apnea (OSA).MethodsWe developed the Subjective Apnea Severity Questionnaire (SASQ) to measure subjective OSA symptoms during the night and on waking in the morning. Construct validity and reliability were assessed. The Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and State Scale of State Trait Anxiety Inventory (STAI-S) were applied. Multiple linear regression analyses were performed, and the results were adjusted for several confounders.ResultsA total of 337 OSA patients were included. The SASQ consists of eight items with three domains. Cronbach's α for the SASQ was 0.657. The mean SASQ score was 1.35 ± 0.59. Symptoms related to nocturnal breathing difficulties were associated with polysomnographic (PSG) respiratory parameters. In the adjusted models, total SASQ scores were associated with ESS scores but not with BDI or STAI-S scores. Unlike other symptom groups, nocturnal breathing difficulties tended toward a positive relationship with ESS scores (p = 0.076), but were negatively related to BDI scores (p = 0.003) and STAI-S scores (p = 0.012). Symptoms related to nocturnal awakening or morning waking were either positively related or unrelated to ESS, BDI, and STAI-S scores.ConclusionsThe subjective OSA symptoms measured via the SASQ were associated with daytime sleepiness in adults with OSA, but not with depressive symptoms or anxiety. Nocturnal breathing difficulties were positively related to daytime sleepiness, but negatively related to depressive symptoms and anxiety.     

Racial disparities in sleep health between Black and White young adults: The role of neighborhood safety in childhood

ObjectivesBlack adults in the United States have shorter sleep durations and poorer sleep efficiency relative to White adults, yet reasons for these disparities are not well explicated. The objective of this study was to examine neighborhood safety in childhood as a mediator of subsequent racial disparities in sleep.MethodsData were from Black and White young adults attending a large, predominantly White university in the Southeastern United States (N = 263; 52% Black, 53% female; Mean age = 19.21 years, SD = 1.01). Sleep parameters were assessed from eight nights of wrist actigraphy (time in bed, sleep duration, and efficiency) and an established self-report measure of daytime sleepiness. Residential histories from birth through age 18 were documented, and retrospective self-reports of neighborhood safety in childhood were assessed.ResultsBlack participants had less time in bed (p < 0.001), shorter sleep duration (p < 0.001), poorer sleep efficiency (p < 0.001), and more daytime sleepiness (p = 0.009) than White participants. Neighborhood safety mediated race differences in time in bed (p = 0.028), sleep duration (p = 0.033), and daytime sleepiness (p = 0.048), but not sleep efficiency. Findings were substantively unchanged after adjustment for family socioeconomic status, BMI, and substance use.ConclusionsFindings support the hypothesis that neighborhood safety in childhood may partially account for race differences in subsequent sleep duration and daytime sleepiness. Addressing racial inequities in childhood neighborhood safety may be an important step toward reducing racial disparities in sleep health.     

Prevalence and neurophysiological correlates of sleep disordered breathing in pediatric type 1 narcolepsy

Study objectivesTo investigate the prevalence and neurophysiological correlates of obstructive sleep disordered breathing (OSA) in type 1 narcolepsy (NT1) children and adolescents.MethodsThirty-eight, drug-naïve, NT1 children and adolescents and 21 age- and sex-balanced clinical controls underwent nocturnal polysomnography (PSG) and multiple sleep latency test (MSLT). According to the rules for pediatric population, an obstructive apnea-hypopnea index (Obstructive AHI) ≥ 1 (comprising obstructive and mixed events), defined comorbid OSA.ResultsNT1 children showed higher prevalence of overweight/obesity and severe nocturnal sleep disruption (lower sleep efficiency, and increased N1 sleep stage percentage) coupled with higher motor activity (periodic limb movement index [PLMi] and REM atonia index) compared to clinical controls. Sleep-related respiratory variables did not differ between NT1 and clinical controls (OSA prevalence of 13.2% and 4.8%, respectively). NT1 children with OSA were younger and showed lower N2 sleep stage percentage and higher PLMi than NT1 children without comorbid OSA. Overweight/obesity was not associated with OSA in NT1.ConclusionsDespite higher body mass index (BMI), OSA prevalence did not differ between children with NT1 and clinical controls. OSA in pediatric NT1 patients is a rare and mild comorbidity, further contributing to nocturnal sleep disruption without effects on daytime sleepiness.     

Dexmedetomidine-induced polysomnography as a diagnostic method in obstructive sleep apnea: a reliable alternative method?

BackgroundUnder-diagnosis of obstructive sleep apnea (OSA) is common because of the demanding and time-consuming nature of polysomnography (PSG). Herein, we assessed the utility of a short daytime dexmedetomidine-induced PSG for diagnosis of OSA in adults.MethodsThis was a single-center, prospective, diagnostic trial. We evaluated 86 patients using a full overnight PSG and a short diurnal drug-induced PSG (DIPSG). DIPSG was induced by continuous intravenous dexmedetomidine infusion. Sedation depth was monitored and maintained using the Narcotrend index (50–70). Diagnostic performance for DIPSG with different apnea-hypopnea index (AHI) cut-off values were calculated. Bland–Altman plots used for analysis. Sleep architecture and position were compared.ResultsWe studied 47 OSA patients and 39 healthy volunteers. Sensitivity and specificity for detection of OSA by DIPSG were 92% and 79%, respectively, for an AHI cut-off value of 5, 90% and 77%, respectively, for an AHI cut-off value of 15, and 95% and 85%, respectively, for an AHI cut-off value of 30. The DIPSG bias was −5 (−25; 15) for AHI and −3 (−13; 7) for minimal oxygen saturation. N2 sleep was increased (32.9% vs. 50.75%, respectively; p < 0.01) and REM sleep was decreased (21.35% vs. 1.24%, respectively; p < 0.01) during DIPSG. Twenty-eight (33%) participants had postural shifts during DIPSG. No significant adverse events were observed during DIPSG.ConclusionsDexmedetomidine-induced PSG had a good sensitivity and specificity, and can be used as a screening tool for diagnosis of OSA in adults.Chinese Clinical Trial RegistrationChiCTR1900024044.