Sphinganine is associated with 24-h MAP in the non-sleepy with OSA.

INTRODUCTION: Excessive daytime sleepiness is a debilitating symptom of obstructive sleep apnea (OSA) linked to cardiovascular disease, and metabolomic mechanisms underlying this relationship remain unknown. We examine whether metabolites from inflammatory and oxidative stress-related pathways that were identified in our prior work could be involved in connecting the two phenomena. METHODS: This study included 57 sleepy (Epworth Sleepiness Scale (ESS) ≥ 10) and 37 non-sleepy (ESS < 10) participants newly diagnosed and untreated for OSA that completed an overnight in-lab or at home sleep study who were recruited from the Emory Mechanisms of Sleepiness Symptoms Study (EMOSS). Differences in fasting blood samples of metabolites were explored in participants with sleepiness versus those without and multiple linear regression models were utilized to examine the association between metabolites and mean arterial pressure (MAP). RESULTS: The 24-h MAP was higher in sleepy 92.8 mmHg (8.4) as compared to non-sleepy 88.8 mmHg (8.1) individuals (P = 0.03). Although targeted metabolites were not significantly associated with MAP, when we stratified by sleepiness group, we found that sphinganine is significantly associated with MAP (Estimate = 8.7, SE = 3.7, P = 0.045) in non-sleepy patients when controlling for age, BMI, smoking status, and apnea-hypopnea index (AHI). CONCLUSION: This is the first study to evaluate the relationship of inflammation and oxidative stress related metabolites in sleepy versus non-sleepy participants with newly diagnosed OSA and their association with 24-h MAP. Our study suggests that Sphinganine is associated with 24 hour MAP in the non-sleepy participants with OSA.

A network meta-analysis of different positive airway pressure interventions in obesity hypoventilation syndrome.

Continuous positive airway pressure (CPAP) and different types of non-invasive ventilation (NIV) have been studied in obesity hypoventilation syndrome such as bi-level PAP with back-up rate (BPAP-BUR), BPAP without BUR, and the new hybrid devices that target a pre-set volume by adjustment of pressure support (VT-PS). Although several studies have compared one PAP intervention with the other, none has compared all four in a head-to-head design, which formed the basis of this network meta-analysis. PubMed and Web of Science were searched for potentially includable randomised active comparator trials. Changes in partial pressure of carbon dioxide (PaCO2 ) and Epworth Sleepiness Score (ESS) were the primary outcomes of interest. Network meta-analysis was done in R program using the 'frequentist' framework. A total of seven trials were included. Only VT-PS and BPAP-BUR showed statistically significant reductions in PaCO2 compared to control, with no significant inter-PAP differences except for the comparison between VT-PS and CPAP. Only VT-PS showed a statistically significant improvement in ESS as compared to control, with no other significant inter-PAP differences. P-score ranking (based on effect size and standard errors) and Hasse diagram ranked VT-PS and BPAP as superior to other PAPs for both primary outcomes. There were no significant differences between the different PAP interventions for hospital or emergency department admissions. The results of this network meta-analysis suggest superiority of VT-PS and BPAP over other PAP interventions at least for daytime hypercapnia and subjective daytime somnolence.

Nocturnal Asthma.

Nocturnal asthma has unique pathophysiological mechanisms, comorbid diseases, and intervention. Even though the treatments for asthma have been highly developed, there are a high number of patients with asthma whose symptoms are not well controlled, particularly those with nocturnal asthma in which symptoms occur during the night and interfere with sleep. Moreover, nocturnal asthma also causes poor sleep quality, impairs quality of life, and deteriorates daytime cognitive performance. Overall, the prevalence of nocturnal asthma is estimated to be between 44-61% of patients with asthma. Pathophysiological mechanisms of nocturnal asthma included circadian rhythmicity and diurnal variation of inflammatory process, beta 2-adrenergic receptor polymorphism, and polluted environments. Furthermore, co-morbid conditions, such as obstructive sleep apnea and gastroesophageal reflux disease, may contribute to nocturnal asthma. In addition to optimal medical treatment, management of co-morbid conditions should be considered. Utilization of continuous positive airway pressure (CPAP) has been shown to significantly improve nocturnal symptoms in patients with co-existing obstructive sleep apnea as supported by numerous studies, but improvement of pulmonary function is still controversial. In addition, several studies also demonstrate that use of proton-pump inhibitors may assist those patients with gastroesophageal reflux disease resulting in an increase of peak expiration flow rate and/or FEV1.

Development and Reporting of Prediction Models: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals.

Prediction models aim to use available data to predict a health state or outcome that has not yet been observed. Prediction is primarily relevant to clinical practice, but is also used in research, and administration. While prediction modeling involves estimating the relationship between patient factors and outcomes, it is distinct from casual inference. Prediction modeling thus requires unique considerations for development, validation, and updating. This document represents an effort from editors at 31 respiratory, sleep, and critical care medicine journals to consolidate contemporary best practices and recommendations related to prediction study design, conduct, and reporting. Herein, we address issues commonly encountered in submissions to our various journals. Key topics include considerations for selecting predictor variables, operationalizing variables, dealing with missing data, the importance of appropriate validation, model performance measures and their interpretation, and good reporting practices. Supplemental discussion covers emerging topics such as model fairness, competing risks, pitfalls of "modifiable risk factors", measurement error, and risk for bias. This guidance is not meant to be overly prescriptive; we acknowledge that every study is different, and no set of rules will fit all cases. Additional best practices can be found in the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines, to which we refer readers for further details.

Home Sleep Apnea Testing for the Diagnosis of Obstructive Sleep Apnea.

A 50-year-old patient with epilepsy, hypertension, loud snoring, recent 50-lb weight gain, and abrupt awakenings with a feeling of breathlessness but no headaches or excessive daytime sleepiness presented with concerns. What would you do next?

The association of sleep quality, delirium, and sedation status with daily participation in physical therapy in the ICU.

BACKGROUND: Poor sleep is common in the ICU setting and may represent a modifiable risk factor for patient participation in ICU-based physical therapy (PT) interventions. This study evaluates the association of perceived sleep quality, delirium, sedation, and other clinically important patient and ICU factors with participation in physical therapy (PT) interventions. METHOD: This was a secondary analysis of a prospective observational study of sleep in a single academic medical ICU (MICU). Perceived sleep quality was assessed using the Richards-Campbell Sleep Questionnaire (RCSQ) and delirium was assessed using the Confusion Assessment Method for the ICU (CAM-ICU). Other covariates included demographics, pre-hospitalization ambulation status, ICU admission diagnosis, daily mechanical ventilation status, and daily administration of benzodiazepines and opioids via bolus and continuous infusion. Associations with participation in PT interventions were assessed among patients eligible for PT using a multinomial Markov model with robust variance estimates. RESULTS: Overall, 327 consecutive MICU patients completed ≥1 assessment of perceived sleep quality. After adjusting for all covariates, daily assessment of perceived sleep quality was not associated with transitioning to participate in PT the following day (relative risk ratio [RRR] 1.02, 95 % CI 0.96-1.07, p = 0.55). However, the following factors had significant negative associations with participating in subsequent PT interventions: delirium (RRR 0.58, 95 % CI 0.41-0.76, p <0.001), opioid boluses (RRR 0.68, 95 % CI 0.47-0.99, p = 0.04), and continuous sedation infusions (RRR 0.58, 95 % CI 0.40-0.85, p = 0.01). Additionally, in patients with delirium, benzodiazepine boluses further reduced participation in subsequent PT interventions (RRR 0.25, 95 % CI 0.13-0.50, p <0.001). CONCLUSIONS: Perceived sleep quality was not associated with participation in PT interventions the following day. However, continuous sedation infusions, opioid boluses, and delirium, particularly when occurring with administration of benzodiazepine boluses, were negatively associated with subsequent PT interventions and represent important modifiable factors for increasing participation in ICU-based PT interventions.

Society of Anesthesia and Sleep Medicine Guidelines on Preoperative Screening and Assessment of Adult Patients With Obstructive Sleep Apnea.

The purpose of the Society of Anesthesia and Sleep Medicine guideline on preoperative screening and assessment of adult patients with obstructive sleep apnea (OSA) is to present recommendations based on the available clinical evidence on the topic where possible. As very few well-performed randomized studies in this field of perioperative care are available, most of the recommendations were developed by experts in the field through consensus processes involving utilization of evidence grading to indicate the level of evidence upon which recommendations were based. This guideline may not be appropriate for all clinical situations and all patients. The decision whether to follow these recommendations must be made by a responsible physician on an individual basis. Protocols should be developed by individual institutions taking into account the patients' conditions, extent of interventions and available resources. This practice guideline is not intended to define standards of care or represent absolute requirements for patient care. The adherence to these guidelines cannot in any way guarantee successful outcomes and is rather meant to help individuals and institutions formulate plans to better deal with the challenges posed by perioperative patients with OSA. These recommendations reflect the current state of knowledge and its interpretation by a group of experts in the field at the time of publication. While these guidelines will be periodically updated, new information that becomes available between updates should be taken into account. Deviations in practice from guidelines may be justifiable and such deviations should not be interpreted as a basis for claims of negligence.

Delirium transitions in the medical ICU: exploring the role of sleep quality and other factors.

OBJECTIVES: Disrupted sleep is a common and potentially modifiable risk factor for delirium in the ICU. As part of a quality improvement project to promote sleep in the ICU, we examined the association of perceived sleep quality ratings and other patient and ICU risk factors with daily transition to delirium. DESIGN: Secondary analysis of prospective observational study. SETTING: Medical ICU over a 201-day period. PATIENTS: Two hundred twenty-three patients with greater than or equal to one night in the medical ICU in between two consecutive days of delirium assessment. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Daily perceived sleep quality ratings were measured using the Richards-Campbell Sleep Questionnaire. Delirium was measured twice daily using the Confusion Assessment Method for the ICU. Other covariates evaluated included age, sex, race, ICU admission diagnosis, nighttime mechanical ventilation status, prior day's delirium status, and daily sedation using benzodiazepines and opioids, via both bolus and continuous infusion. Perceived sleep quality was similar in patients who were ever versus never delirious in the ICU (median [interquartile range] ratings, 58 [35-76] vs 57 [33-78], respectively; p = 0.71), and perceived sleep quality was unrelated to delirium transition (adjusted odds ratio, 1.00; 95% CI, 0.99-1.00). In mechanically ventilated patients, receipt of a continuous benzodiazepine and/or opioid infusion was associated with delirium transition (adjusted odds ratio, 4.02; 95% CI, 2.19-7.38; p < 0.001), and patients reporting use of pharmacological sleep aids at home were less likely to transition to delirium (adjusted odds ratio, 0.40; 95% CI, 0.20-0.80; p = 0.01). CONCLUSIONS: We found no association between daily perceived sleep quality ratings and transition to delirium. Infusion of benzodiazepine and/or opioid medications was strongly associated with transition to delirium in the ICU in mechanically ventilated patients and is an important, modifiable risk factor for delirium in critically ill patients.

An official American Thoracic Society Clinical Practice Guideline: sleep apnea, sleepiness, and driving risk in noncommercial drivers. An update of a 1994 Statement.

BACKGROUND: Sleepiness may account for up to 20% of crashes on monotonous roads, especially highways. Obstructive sleep apnea (OSA) is the most common medical disorder that causes excessive daytime sleepiness, increasing the risk for drowsy driving two to three times. The purpose of these guidelines is to update the 1994 American Thoracic Society Statement that described the relationships among sleepiness, sleep apnea, and driving risk. METHODS: A multidisciplinary panel was convened to develop evidence-based clinical practice guidelines for the management of sleepy driving due to OSA. Pragmatic systematic reviews were performed, and the Grading of Recommendations, Assessment, Development, and Evaluation approach was used to formulate and grade the recommendations. Critical outcomes included crash-related mortality and real crashes, whereas important outcomes included near-miss crashes and driving performance. RESULTS: A strong recommendation was made for treatment of confirmed OSA with continuous positive airway pressure to reduce driving risk, rather than no treatment, which was supported by moderate-quality evidence. Weak recommendations were made for expeditious diagnostic evaluation and initiation of treatment and against the use of stimulant medications or empiric continuous positive airway pressure to reduce driving risk. The weak recommendations were supported by very low-quality evidence. Additional suggestions included routinely determining the driving risk, inquiring about additional causes of sleepiness, educating patients about the risks of excessive sleepiness, and encouraging clinicians to become familiar with relevant laws. DISCUSSION: The recommendations presented in this guideline are based on the current evidence, and will require an update as new evidence and/or technologies becomes available.

Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary.

This multisociety commentary critically examines the Agency for Healthcare Research and Quality (AHRQ) final report and systematic review on long-term health outcomes in obstructive sleep apnea. The AHRQ report was commissioned by the Centers for Medicare & Medicaid Services and particularly focused on the long-term patient-centered outcomes of continuous positive airway pressure, the variability of sleep-disordered breathing metrics, and the validity of these metrics as surrogate outcomes. This commentary raises concerns regarding the AHRQ report conclusions and their potential implications for policy decisions. A major concern expressed in this commentary is that the AHRQ report inadequately acknowledges the benefits of continuous positive airway pressure for several established, long-term clinically important outcomes including excessive sleepiness, motor vehicle accidents, and blood pressure. While acknowledging the limited evidence for the long-term benefits of continuous positive airway pressure treatment, especially cardiovascular outcomes, as summarized by the AHRQ report, this commentary reviews the limitations of recent randomized controlled trials and nonrandomized controlled studies and the challenges of conducting future randomized controlled trials. A research agenda to address these challenges is proposed including study designs that may include both high quality randomized controlled trials and nonrandomized controlled studies. This commentary concludes by highlighting implications for the safety and quality of life for the millions of people living with obstructive sleep apnea if the AHRQ report alone was used by payers to limit coverage for the treatment of obstructive sleep apnea while not considering the totality of available evidence. CITATION: Patil SP, Billings ME, Bourjeily G, et al. Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary. J Clin Sleep Med. 2024;20(1):135-149.

Insights, recommendations, and research priorities for central sleep apnea: report from an expert panel.

Central sleep apnea (CSA) is commonly encountered among patients with sleep-disordered breathing, however its clinical consequences are less well-characterized. We therefore convened an expert panel to discuss the common presentations of CSA, as well as challenges and knowledge gaps in the diagnosis and management of CSA. The panel identified several key research priorities essential for advancing our understanding of the disorder. Within the diagnostic realm, panel members discussed the utility of multi-night assessments, and importance of the development and validation of novel metrics and automated assessments for differentiating central versus obstructive hypopneas, such that their impact on clinical outcomes and management may be better evaluated. The panel also discussed the current therapeutic landscape for the management of CSA and agreed that therapies should primarily aim to alleviate sleep-related symptoms, after optimizing treatment to address the underlying cause. Most importantly, the panel concluded that there is a need to further investigate the clinical consequences of CSA, as well as the implications of therapy on clinical outcomes, particularly among those who are asymptomatic. Future research should focus on endo-phenotyping central events for a better mechanistic understanding of the disease, validating novel diagnostic methods for implementation in routine clinical practice, as well as the use of combination therapy and comparative effectiveness trials in elucidating the most efficacious interventions for managing CSA.

The effect of a quality improvement intervention on perceived sleep quality and cognition in a medical ICU.

OBJECTIVES: To determine if a quality improvement intervention improves sleep and delirium/cognition. DESIGN: Observational, pre-post design. SETTING: A tertiary academic hospital in the United States. PATIENTS: 300 medical ICU patients. INTERVENTIONS: This medical ICU-wide project involved a "usual care" baseline stage, followed by a quality improvement stage incorporating multifaceted sleep-promoting interventions implemented with the aid of daily reminder checklists for ICU staff. MEASUREMENTS AND MAIN RESULTS: Primary ICU outcomes were perceived sleep quality and noise ratings (measured on a 0-100 scale using the valid and reliable Richards-Campbell Sleep Questionnaire) and delirium/coma-free days. Secondary outcomes included ICU and hospital length of stay and mortality. Post-ICU measures of cognition and perceived sleep quality were evaluated in an ICU patient subset. During the baseline and sleep quality improvement stages, there were 122 and 178 patients, respectively, with more than one night in the ICU, accounting for 634 and 826 patient-days. Within the groups, 78 (63.9%) and 83 (46.6%) patients received mechanical ventilation. Over the 826 patient-day quality improvement period, checklist item completion rates ranged from 86% to 94%. In multivariable regression analysis of the quality improvement vs. baseline stages, improvements in overall Richards-Campbell Sleep Questionnaire sleep quality ratings did not reach statistical significance, but there were significant improvements in daily noise ratings (mean ± SD: 65.9±26.6 vs. 60.5±26.3, p = 0.001), incidence of delirium/coma (odds ratio: 0.46; 95% confidence interval, 0.23-0.89; p = 0.02), and daily delirium/coma-free status (odds ratio: 1.64; 95% confidence interval, 1.04-2.58; p = 0.03). Improvements in secondary ICU outcomes and post-ICU outcomes did not reach statistical significance. CONCLUSIONS: An ICU-wide quality improvement intervention to improve sleep and delirium is feasible and associated with significant improvements in perceived nighttime noise, incidence of delirium/coma, and daily delirium/coma-free status. Improvement in perceived sleep quality did not reach statistical significance.

A prospective photographic study of the ocular fundus in obstructive sleep apnea.

BACKGROUND: The prevalence of optic nerve and retinal vascular changes within the obstructive sleep apnea (OSA) population are not well-known, although it has been postulated that optic nerve ischemic changes and findings related to an elevated intracranial pressure may be more common in OSA patients. We prospectively evaluated the ocular fundus in unselected patients undergoing overnight diagnostic polysomnography (PSG). METHODS: Demographic data, medical/ocular history, and nonmydriatic fundus photographs were prospectively collected in patients undergoing PSG at our institution and reviewed for the presence of optic disc edema for which our study was appropriately powered a priori. Retinal vascular changes were also evaluated. OSA was defined using the measures of both sleep-disordered breathing and hypoxia. RESULTS: Of 250 patients evaluated in the sleep center, fundus photographs were performed on 215 patients, among whom 127 patients (59%) had an apnea/hypopnea index (AHI) ≥ 15 events per hour, including 36 with severe OSA. Those with AHI <15 served as the comparison group. None of the patients had optic disc edema (95% confidence interval [CI]: 0%-3%). There was no difference in rates of glaucomatous appearance or pallor of the optic disc among the groups. Retinal arteriolar changes were more common in severe OSA patients (odds ratio: 1.09 per 5 unit increase in AHI; 95% CI, 1.02-1.16; P = 0.01), even after controlling for mean arterial blood pressure. CONCLUSIONS: We did not find an increased prevalence of optic disc edema or other optic neuropathies in our OSA population. However, retinal vascular changes were more common in patients with severe OSA, independent of blood pressure.

Examining the feasibility of adult quality-of-life measurement for obstructive sleep apnea in clinical settings: what is the path forward for sleep centers?

Quality of life (QoL) is one of the outcomes that can be measured as a component of the required standards for sleep facility accreditation by the American Academy of Sleep Medicine. Utilization of a psychometrically robust QoL instrument is recommended; however, clinicians face a challenge balancing psychometric properties with questionnaire completion and scoring characteristics. This article provides an overview of common QoL instruments as a reference for clinicians when selecting a QoL tool for use in the clinical setting for adult patients with obstructive sleep apnea. CITATION: Colvin L, Collop N, Lorenz R, Morgenthaler T, Weaver TE. Examining the feasibility of adult quality-of-life measurement for obstructive sleep apnea in clinical settings: what is the path forward for sleep centers? J Clin Sleep Med. 2023;19(6):1145-1155.

Sleep deprivation in critical illness: its role in physical and psychological recovery.

Critically ill patients frequently experience poor sleep, characterized by frequent disruptions, loss of circadian rhythms, and a paucity of time spent in restorative sleep stages. Factors that are associated with sleep disruption in the intensive care unit (ICU) include patient-ventilator dysynchrony, medications, patient care interactions, and environmental noise and light. As the field of critical care increasingly focuses on patients' physical and psychological outcomes following critical illness, understanding the potential contribution of ICU-related sleep disruption on patient recovery is an important area of investigation. This review article summarizes the literature regarding sleep architecture and measurement in the critically ill, causes of ICU sleep fragmentation, and potential implications of ICU-related sleep disruption on patients' recovery from critical illness. With this background information, strategies to optimize sleep in the ICU are also discussed.

Perioperative care of patients with obstructive sleep apnea.

OPINION STATEMENT: It has been demonstrated that patients undergoing surgical procedures are at increased risk for complications if they have obstructive sleep apnea. It is believed that this increase in risk is related to more difficult intubations, use of ventilatory depressant medications, and perhaps body positioning. Although identifying patients with a preexisting diagnosis of sleep apnea is important so they can be triaged appropriately during the perioperative period, a bigger challenge is trying to identify patients who require a surgical procedure and may have undiagnosed sleep apnea. Hospitals and surgical centers should have policies in place to assist in such identification preoperatively, with a protocol on how to manage such patients perioperatively. Such guidelines exist, but many institutions do not have such protocols in place or fail to ensure that they are consistently followed. The key to the perioperative management is close observation of these high-risk patients. In ambulatory surgery populations, these patients should be observed for an extended period before being discharged to home. In inpatient settings, the observation can be tailored to the patient's postoperative risks based on the type of surgery and the severity of his or her sleep apnea. Patients undergoing bariatric surgery are at particularly high risk. These patients have a very high prevalence of sleep apnea and comorbid conditions. Screening this population for obstructive sleep apnea is mandatory, and a plan for postoperative observation should be in place in all institutions performing such surgery.

Optimal NIV Medicare Access Promotion: Patients With OSA: A Technical Expert Panel Report From the American College of Chest Physicians, the American Association for Respiratory Care, the American Academy of Sleep Medicine, and the American Thoracic Society.

This document summarizes the work of the CPAP and bilevel PAP therapy for OSA Technical Expert Panel working group. For positive airway pressure (PAP) therapy, the most pressing current coverage barriers identified were: an insufficient symptom list describing all potential symptoms in patients with mild OSA; the 4 h per night of PAP usage requirement to keep the device; the additional sleep studies requirement to re-qualify for PAP or supplemental oxygen; and the inability to use telehealth visits for follow-up visits. Critical evidence supports changes to current policies and includes: symptom list inadequate to cover all scenarios based on updated clinical practice guidelines; published evidence that 2 h per night of PAP use can result in benefit to quality of life and other metrics; the costs of another sleep study not justified for all nonadherent patients or for supplemental oxygen due to other types of assessment currently available; and the remarkable success and acceptance of telehealth visits. To achieve optimal access for patients on PAP therapy, we make the following key suggestions: removing symptom criteria for mild OSA; reduce continued coverage criteria to > 2 h per night; eliminate the need for a sleep study to re-qualify if nonadherent or for new Centers for Medicare & Medicaid Services beneficiaries already on and adherent to PAP therapy; allow telehealth visits for documenting benefit and adherence; and allow PAP reports and domiciliary oximetry to qualify for supplemental oxygen with PAP if needed. This paper shares our best vision for bringing the right device to the right patient at the right time.

Randomized Controlled Trial of a Novel Communication Device Assessed During Noninvasive Ventilation Therapy.

BACKGROUND: Noninvasive ventilation (NIV), a form of positive airway pressure (PAP) therapy, is the standard of care for various forms of acute respiratory failure (ARF). Communication impairment is a side effect of NIV, impedes patient care, contributes to distress and intolerance, and potentially increases intubation rates. This study aimed to evaluate communication impairment during CPAP therapy and demonstrate communication device improvement with a standardized protocol. RESEARCH QUESTION: How does an oronasal mask affect communication intelligibility? How does use of an NIV communication device change this communication intelligibility? STUDY DESIGN AND METHODS: A single-center randomized controlled trial (36 outpatients with OSA on CPAP therapy) assessed exposure to CPAP 10 cm H2O and PAP communication devices (SPEAX, Ataia Medical). Communication impairment was evaluated by reading selected words and sentences for partners to record and were tabulated as %words correct. Each outpatient-partner pair performed three assessments: (1) baseline (conversing normally), (2) mask baseline (conversing with PAP), and (3) randomized to functioning device (conversing with PAP and device) or sham device. After each stage, both outpatients and partners completed Likert surveys regarding perceived intelligibility and comfort. RESULTS: While conversing with PAP, word and sentence intelligibility decreased relatively by 52% (87% vs 41%) and relatively by 57% (94% vs 40%), respectively, compared with normal conversation. Word and sentence intelligibility in the intervention arm increased relatively by 75% (35% vs 61%; P < .001) and by 126% (33% vs 76%; P < .001) higher than the control arm, respectively. The device improved outpatient-perceived PAP comfort relatively by 233% (15% vs 50%, P = .042) and partner-perceived comfort by relatively 245% (20% vs 69%, P = .0074). INTERPRETATION: Use of this PAP communication device significantly improves both intelligibility and comfort. This is one of the first studies quantifying communication impairment during PAP delivery. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03795753; URL: www.clinicaltrials.gov.

Metrics of sleep apnea severity: beyond the apnea-hypopnea index.

Obstructive sleep apnea (OSA) is thought to affect almost 1 billion people worldwide. OSA has well established cardiovascular and neurocognitive sequelae, although the optimal metric to assess its severity and/or potential response to therapy remains unclear. The apnea-hypopnea index (AHI) is well established; thus, we review its history and predictive value in various different clinical contexts. Although the AHI is often criticized for its limitations, it remains the best studied metric of OSA severity, albeit imperfect. We further review the potential value of alternative metrics including hypoxic burden, arousal intensity, odds ratio product, and cardiopulmonary coupling. We conclude with possible future directions to capture clinically meaningful OSA endophenotypes including the use of genetics, blood biomarkers, machine/deep learning and wearable technologies. Further research in OSA should be directed towards providing diagnostic and prognostic information to make the OSA diagnosis more accessible and to improving prognostic information regarding OSA consequences, in order to guide patient care and to help in the design of future clinical trials.

Sleep and sleep disorders in chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death in the US. Numerous studies have demonstrated that sleep disturbances are common in COPD patients, with more prominent complaints in patients with more severe disease and with increasing age. Sleep disturbances may occur due to the effects of breathing abnormalities on sleep and sleep disruption. However, other etiologies may include the medications used to treat COPD, concomitant anxiety and depression, and the presence of comorbid sleep disorders. The respiratory disturbances that occur in these patients during sleep have been evaluated by examining sleep-related oxygen desaturation, reduction in pulmonary function during sleep, and development of hypoventilation during rapid eye movement sleep. Treatment includes use of nocturnal oxygen therapy, noninvasive positive pressure ventilation, and long-acting medications. There has been little study on improving sleep quality beyond treating the respiratory disease, despite the fact that numerous studies show poor sleep quality, a high prevalence of insomnia, and tolerability of newer hypnotic agents in the setting of COPD. This article defines the scope of sleep problems in the setting of COPD, reviews the impact of sleep on ventilation, explores the role of obstructive sleep apnea in the setting of COPD, and reviews therapeutic options.