Sleep apnea and cardiovascular disease: an American Heart Association/American College of Cardiology Foundation Scientific Statement from the American Heart Association Council for High Blood Pressure Research Professional Education Committee, Council on Clinical Cardiology, Stroke Council, and Council on Cardiovascular Nursing

Evaluating the impact of different message strategies about OSA employed in the American Academy of Sleep Medicine Count on Sleep campaign

Health campaigns hold promise for promoting general awareness about obstructive sleep apnea. In 2023, the American Academy of Sleep Medicine developed a series of messages as part of their "Count on Sleep" campaign. Three distinct messaging strategies were employed in posts disseminated on Facebook: (1) positive outcome (benefits of obstructive sleep apnea treatment); (2) negative outcome (consequences of untreated obstructive sleep apnea); and (3) partner-focused. We evaluated Facebook analytics to explore which of the 3 strategies was most impactful. The impressions were highest for the positive outcome message (n = 120,062), followed by the negative outcome (n = 12,286) and partner-focused (n = 10,259) messages. Female users were more likely to engage with positive (39% vs 28%) and negative (34% vs 25%) message than males, but sexes were quite balanced in engagement with the partner-focused message (36% vs 36%). There was more engagement from older adults (65 years and older) than from younger adults across all message types.

CITATION

Robbins R, Morkous SSW, Honaker S, Darby CV, DelRosso LM. Evaluating the impact of different message strategies about OSA employed in the American Academy of Sleep Medicine Count on Sleep campaign. J Clin Sleep Med. 2025;21(2):417-419.

Effect of CPAP therapy on blood pressure in patients with obstructive sleep apnoea: a worldwide individual patient data meta-analysis

BACKGROUND

Obstructive sleep apnoea (OSA) is associated with hypertension, and OSA treatment can reduce systolic blood pressure (SBP) and diastolic blood pressure (DBP), but with a modest mean effect size and vast heterogeneity among studies. The aim of this individual patient data (IPD) meta-analysis was to understand which OSA phenotypes could benefit the most in terms of BP reduction.

METHODS

A systematic review of randomised controlled trials that compared continuous positive airway pressure (CPAP) with either passive or active treatment was conducted. Studies were eligible if they included adult patients with OSA diagnosed by full polysomnography or cardiorespiratory polygraphy (defined as apnoea-hypopnoea index >5 events·h-1) and if BP was measured both before and after CPAP treatment.

RESULTS

In total, 36 parallel studies (n=9434 patients) were included. CPAP treatment was associated with BP reduction in patients with uncontrolled office SBP only, while BP was not reduced by CPAP in patients with controlled BP (SBP -2.6 versus 0 mmHg; p<0.0001; DBP -1.7 versus -1 mmHg; p=0.091). Differences were seen also when BP changes were compared between patients aged ≤60 versus >60 years after multiple imputation only (p=0.0127 for SBP and p=0.017 for DBP). No differences were seen in terms of BP reduction when comparing patients with/without severe nocturnal hypoxia.

CONCLUSIONS

This IPD meta-analysis of the BP effects of OSA treatment with CPAP shows that OSA patients with uncontrolled BP at baseline benefit the most from CPAP therapy in terms of BP reduction. These results have important implications for the decision on how to best manage arterial hypertension associated with OSA.

Comparison of Home Sleep Devices and Sleep Study Testing in Hypoglossal Nerve Stimulation Patients

OBJECTIVE

Hypoglossal nerve stimulation (HGNS) is an implantable therapy for obstructive sleep apnea (OSA). Therapy efficacy is currently confirmed by a formal sleep study after empiric adjustment by the patient at home based on their subjective experience with the device. Home-based longitudinal apnea hypopnea index (AHI) measurements have the potential to refine HGNS therapeutic amplitude selection with objective data. Our objective was to compare AHI derived from routine sleep studies and two different home sleep devices in new HGNS recipients.

METHODS

Prospectively enrolled patients receiving HGNS therapy were provided a Sleep Tracking Mat (Withings, Issy-les-Moulineaux, France) and NightOwl peripheral arterial tonometry (PAT) sensor (Ectosense, Leuven, Belgium) for longitudinal, home AHI monitoring from 1 to 6 months post-implant. Therapy efficacy was assessed at 3 and 6 months post-implant using in-lab polysomnography (PSG) or home sleep apnea test (HSAT). The sleep mat and PAT sensor AHI were compared against PSG and HSAT for accuracy of OSA severity identification.

RESULTS

Sixty patients were enrolled across 5 centers and followed for 6 months. The sleep mat had sensitivity and specificity for identifying AHI <15 of 61% and 82% and AHI <30 of 77% and 100%. The PAT device had sensitivity and specificity for identifying AHI <15 of 57% and 77% and AHI <30 of 81% and 80%.

CONCLUSIONS

The sleep mat and PAT sensor demonstrated high sensitivity and specificity for detection of mild and moderate OSA in patients with HGNS therapy and may enable longitudinal objective monitoring of HGNS efficacy in the home setting.

LEVEL OF EVIDENCE

3 Laryngoscope, 135:469-477, 2025.

Sleep as a window of cardiometabolic health: The potential of digital sleep and circadian biomarkers

Digital biomarkers are quantifiable and objective indicators of a person's physiological function, behavioral state or treatment response, that can be captured using connected sensor technologies such as wearable devices and mobile apps. We envision that continuous and 24-h monitoring of the underlying physiological and behavioral processes through digital biomarkers can enhance early diagnostics, disease management, and self-care of cardiometabolic diseases. Cardiometabolic diseases, which include a combination of cardiovascular and metabolic disorders, represent an emerging global health threat. The prevention potential of cardiometabolic diseases is around 80%, indicating a promising role for interventions in the lifestyle and/or the environmental context. Disruption of sleep and circadian rhythms are increasingly recognized as risk factors for cardiometabolic disease. Digital biomarkers can be used to measure around the clock, that is, day and night, to quantify not only sleep patterns but also diurnal fluctuations of certain biomarkers and processes. In this way, digital biomarkers can support the delivery of optimal timed medical care. Night-time cardiometabolic patterns, such as blood pressure dipping, are predictive of cardiometabolic health outcomes. In addition, the sleep period provides an opportunity for digital cardiometabolic health monitoring with relatively low influence of artifacts, such as physical activity and eating. Digital biomarkers that utilize sleep as a window of health can be used during daily life to enable early diagnosis of cardiometabolic diseases, facilitate remote patient monitoring, and support self-management in people with cardiometabolic diseases. This review describes the influence of sleep and circadian rhythms on cardiometabolic disease and highlights the state-of-the-art sleep and circadian digital biomarkers which could be of benefit in the prevention of cardiometabolic disease.

Effect of continuous positive airway pressure on cardiometabolic risk factors in patients with obstructive sleep apnea: A systematic review and meta-analysis

OBJECTIVE

Cardiometabolic risk factors (CMRFs) play a crucial role in the occurrence and development of cardiovascular diseases. Obstructive sleep apnea (OSA) causes abnormalities of CMRFs. Continuous positive airway pressure (CPAP) is a widely used treatment for OSA. This systematic review and meta-analysis aimed to investigate the effect of CPAP on CMRFs in patients with OSA.

METHODS

A search of PubMed, Cochrane Library, Scopus, Web of Science, and Embase was conducted to find randomized controlled trials up to December 3, 2023. The quality of the studies included was evaluated using the Cochrane Bias Risk Tool 2.0, and a meta-analysis was carried out using Stata15.1 software. The effect sizes for this meta-analysis were represented as the weighted mean difference (WMD) and 95 % confidence interval (CI).

RESULTS

A total of 52 studies with 10,104 participants were analyzed. The results showed that CPAP significantly lowered systolic blood pressure (WMD: -2.04 mmHg; 95%CI: -3.56 to -0.51), diastolic blood pressure (WMD: -1.40 mmHg; 95%CI: -2.36 to -0.44), total cholesterol (WMD: -0.27 mmol/L; 95%CI: -0.51 to -0.04), triglycerides (WMD: -0.02 mmol/L; 95%CI: -0.03 to -0.01), and fasting blood glucose (WMD: -0.15 mmol/L; 95%CI: -0.16 to -0.13) in patients with OSA. However, there was no significant change in low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, waist circumference, or body mass index after CPAP.

CONCLUSION

In summary, this meta-analysis demonstrated that CPAP effectively reduced certain CMRFs in patients with OSA, offering new insights for cardiovascular disease prevention.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier CRD42023456380.

Achieving adherence to positive airway pressure in commercial drivers using an employer-mandated remote management programme

Background

Obstructive sleep apnoea (OSA) is common in commercial drivers, and associated with increased risk of crashes if untreated, making diagnosis and effective treatment crucial in this population.

Study design and methods

This is a retrospective summary of a clinical programme based on telemedicine and remote treatment monitoring developed with a national trucking company to screen new hires in the USA for OSA and implement positive airway pressure (PAP) management. New hires were informed of the programme and consented as part of their employment. Drivers who did not comply with the evaluation or with PAP after diagnosis were removed from driving commercial vehicles by the company or did not pursue further employment.

Results

A total of 975 drivers were enrolled. Among screened drivers, 35.5% were cleared without a sleep study, 15.0% were cleared following a sleep study (apnoea-hypopnoea index (AHI) <5 events·h-1), 22.1% had mild OSA (AHI 5-15) and 27.4% had moderate-severe OSA (AHI ≥15). Those with moderate-severe OSA were more obese (body mass index 36.2±6.3 kg·m-2) and had more comorbidities. Of 269 drivers starting PAP, 160 (59.5%) maintained participation in a care management programme, 80 (29.7%) resigned or were terminated, 23 (8.6%) were cleared to discontinue PAP and six (2.2%) were complex cases requiring transfer of care. Illustrating effectiveness, those that maintained participation had excellent PAP adherence (5.27±1.61 h·night-1; 88.5±12.9% days used; 79.7±17.7% days used ≥4 h).

Interpretation

Remote assessment of OSA and PAP management in commercial drivers is feasible and effective. This approach has wide-ranging applications, particularly in populations and areas with a lack of sleep medicine providers.

Prevalence and Risk Factors for Secondary Hypertension in Young Adults

BACKGROUND

The prevalence of secondary causes of hypertension in young adults is unknown, and therefore, there is no consensus about the indication of screening of secondary hypertension (2HTN) in this population. The objective was to report the prevalence and the causes of 2HTN in young subjects.

METHODS

In this cross-sectional study, 2090 patients with confirmed hypertension aged 18 to 40 years with full workup for 2HTN screening were included. We assessed the prevalence of 2HTN and analyzed the factors associated.

RESULTS

Among 2090 patients, 619 (29.6%) had a 2HTN. The most frequent diagnoses of 2HTN in descending order were primary aldosteronism (n=339; 54.8%), renovascular hypertension (n=114; 18.4%), primary kidney disease (n=80; 12.9%), pheochromocytoma/functional paraganglioma (n=37; 5.9%), hypertension caused by drugs or substances (n=32; 6.0%), and other diagnoses (n=17; 2.7%). Patients with blood pressure <160/100 mm Hg did not have a lower prevalence of 2HTN regardless of the number of treatments. The prevalence of 2HTN was higher in the decade between 30 and 40 years of age than between 18 and 30 years of age (P=0.024). Female sex, hypokalemia, treatment with at least 2 medications, no familial history of hypertension, body mass index <25 kg/m², and diabetes were associated with a higher prevalence of 2HTN.

CONCLUSIONS

The prevalence of 2HTN is high among young patients with hypertension (29.6% in our cohort), regardless of age and blood pressure level. All patients with hypertension under 40 years of age should be screened for secondary causes.

Insights into the Overlap of Chronic Obstructive Pulmonary Disease and Sleep Apnea: Experience from the Clinic of Pneumology, Târgu Mureș

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) has a severe impact on patients' health and can lead to multiple complications.

MATERIAL AND METHODS

We analyzed the co-occurrence of obstructive sleep apnea (OSA) in COPD patients hospitalized in the Pneumology Clinic of Târgu Mureș, Romania.

RESULTS

A total of 150 COPD patients were investigated by clinical examination, STOP-BANG and Epworth questionnaires, ventilatory polygraphy (PG), EKG, cardiac ultrasound, blood lipids, and sugar. Sixty-eight patients (45.3%) had OSA associated with COPD. A total of 61.7% were COPD gr. E, and 30.8% were gr. B. Frequently shown symptoms were snoring and nonrestorative sleep (100%), somnolence (73.5%), nocturnal awakenings (41.17%), morning headache (32.3%), and aggravated dyspnea. Types of OSA included obstructive (97.05%), central (2.5%), and associated obesity-hypoventilation (39.7%). A total of 76.4% were recently diagnosed with OSA. Men predominated at 70.5%, 76.4% were smokers, and 61.7% had experienced alcohol abuse. A total of 25% were overweight, and 71% had obesity. A total of 13.2% belonged to the category of 38-50-year-olds, 55.8% were in the 51-65-year-old category, 17.6% were in the 66-70-year-old category, and roughly 13.2% were in the 71-year-old category. Overlap syndrome (OS) comorbidities and complications were frequently present: 41% experienced respiratory failure, 66.1% experienced blood hypertension, 58.8% experienced ischemic cardiac disease, 32.35% experienced diabetes mellitus, 50% experienced dyslipidemia, and 29.4% experienced cor pulmonale.

CONCLUSIONS

OS conferred gravity or directly contributed to cardiovascular, respiratory, and metabolic complications. OS was associated with more severe COPD and obesity. The prevalence of smoking in OS patients was higher than the national/European average.

Triglyceride glucose-body mass index as a mediator of hypertension risk in obstructive sleep apnoea syndrome: a mediation analysis study

The aim of this study was to investigate whether triglyceride glucose-body mass index (TyG-BMI) plays a mediating role between obstructive sleep apnoea syndrome (OSAS) and hypertension. The study analyzed clinical data from a total of 840 OSAS patients at Wuhan Union Hospital between January 2020 to December 2023. The association between TyG-BMI and hypertension was examined using restricted cubic spline regression and logistic regression. Mediation effect analysis was conducted to explore the relationship between OSAS, TyG-BMI, and the risk of hypertension. Severe OSAS was associated with a significantly increased risk of hypertension compared to mild OSAS (OR = 1.752, p = 0.013). There was a positive linear relationship between TyG-BMI and the risk of hypertension (P-non-linear = 0.535). The risk of hypertension increased with increasing TyG-BMI, with a significantly higher risk of hypertension in the fourth quartile (OR = 3.407, p < 0.001) than in the third quartile (OR = 2.457, p < 0.001) and in the second quartile (OR = 1.576, p = 0.043). TyG-BMI mediated the association between OSAS and hypertension with a mediation effect of 41.3% (p < 0.001). TyG-BMI is important for assessing the risk of hypertension in patients with OSAS.

Sleep Disorders

AbstractThere are more than 90 recognized sleep disorders, many of which impair sleep and daytime function and adversely impact heath, well-being, and chronic disease risk. Unfortunately, many sleep disorders are undiagnosed or not managed effectively. This review describes how to identify, evaluate, and treat common sleep disorders.

Self-efficacy-based Interventions for Patients With Obstructive Sleep Apnea: A Systematic Review

PURPOSE

This study aimed to systematically review self-efficacy-based interventions for patients with obstructive sleep apnea (OSA) and identify the relationship between the number of used techniques for prompting self-efficacy and the main outcome variables.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. Experimental studies on the use of self-efficacy-based interventions for patients with OSA were analyzed. Five databases, EMBASE, CINAHL, PubMed, SCOPUS, and Web of Science, were systematically searched for articles published until December 2023. Interventions were classified based on the behavior change technique (BCT) taxonomy and the theoretical sources of self-efficacy to conduct a narrative synthesis.

RESULTS

Of the 6,968 articles evaluated, 11 were included for analysis (1,304 participants). The results showed that the most frequently employed BCTs in the analyzed studies were "instruction on how to perform a behavior," "exposure," and "social support." Regarding the number of techniques, an average of 6.0 BCTs (range, 4-8) and 3.2 theoretical sources (range, 2-4) were utilized in studies that showed significant improvements in self-efficacy (5 studies), whereas an average of 4.8 BCTs (range, 2-5) and 2.8 theoretical sources (2-3) were used in studies that indicated null results related to self-efficacy (6 studies).

CONCLUSION

This review underscores the potential of self-efficacy-based interventions in the management of OSA and provides a solid theoretical foundation for designing effective interventions. Additionally, the results indicate that utilizing a greater diversity of BCTs and theoretical sources may contribute to the effectiveness of self-efficacy interventions. Therefore, clinicians should consider incorporating various behavior change techniques and four sources of prompting self-efficacy from self-efficacy theory into interventions to enhance self-efficacy, and consequently, treatment adherence in patients with OSA.

Dentoskeletal changes of long-term oral appliance treatment in patients with obstructive sleep apnea: A systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to evaluate the dental and skeletal effects of the long-term oral appliance (OA) treatment in patients with obstructive sleep apnea (OSA) and provide insights for clinicians in treatment planning and decision-making for OSA patients undergoing OA treatment.

MATERIALS AND METHODS

A comprehensive literature search was conducted in major databases up to April 2024. Studies were included if they assessed long-term OA treatment (≥6 months) in adults with OSA using any type of mandibular advancement device (MADs) or tongue retaining device (TRD). Dental and skeletal changes, measured by dental cast and cephalometric analysis, were the primary outcomes.

RESULTS

A total of 42 studies were included in the systematic review, with 23 included in the meta-analysis. Long-term OA treatment was associated with a significant decrease in overbite (0.87 mm, 95% CI: 0.69-1.05) and overjet (0.86 mm, 95% CI: 0.69-1.03). Subgroup analyses showed the decrease of overbite and overjet progressively changed over the years intervals. There was a significant retroclination of the upper incisors (U1-SN, 2.58°, 95% CI: 1.07-4.08) and proclination of the lower incisors (L1-MP, -2.67° (95% CI: -3.78-1.56). Skeletal changes were not significant.

CONCLUSION

Overbite and overjet gradually decreased in the long-term OA treatment, which might predominantly result from the retroclination of the upper incisors and the proclination of the lower incisors. The skeletal patterns in the anteroposterior and vertical direction might remain relatively stable over time. There was a tendency for the clockwise rotation of the mandible.

Respiratory performance in Duchenne muscular dystrophy: Clinical manifestations and lessons from animal models

Duchenne muscular dystrophy (DMD) is a fatal genetic neuromuscular disease. Lack of dystrophin in skeletal muscles leads to intrinsic weakness, injury, subsequent degeneration and fibrosis, decreasing contractile function. Dystropathology eventually presents in all inspiratory and expiratory muscles of breathing, severely curtailing their critical function. In people with DMD, premature death is caused by respiratory or cardiac failure. There is an urgent need to develop therapies that improve quality of life and extend life expectancy in DMD. Surprisingly, there is a dearth of information on respiratory control in animal models of DMD, and respiratory outcome measures are often limited or absent in clinical trials. Characterization of respiratory performance in murine and canine models has revealed extensive remodelling of the diaphragm, the major muscle of inspiration. However, significant compensation by extradiaphragmatic muscles of breathing is evident in early disease, contributing to preservation of peak respiratory system performance. Loss of compensation afforded by accessory muscles in advanced disease is ultimately associated with compromised respiratory performance. A new and potentially more translatable murine model of DMD, the D2.mdx mouse, has recently been developed. Respiratory performance in D2.mdx mice is yet to be characterized fully. However, based on histopathological features, D2.mdx mice might serve as useful preclinical models, facilitating the testing of new therapeutics that rescue respiratory function. This review summarizes the pathophysiological mechanisms associated with DMD both in humans and in animal models, with a focus on breathing. We consider the translational value of each model to human DMD and highlight the urgent need for comprehensive characterization of breathing in representative preclinical models to better inform human trials.

Combination of acute intermittent hypoxia and intermittent transcutaneous electrical stimulation in obstructive sleep apnea: a randomized controlled crossover trial

Intermittent hypoxia (IH) and intermittent transcutaneous electrical stimulation (ITES) might benefit patients with obstructive sleep apnea (OSA). However, the therapeutic value of combined IH and ITES in OSA is unknown. In this prospective, randomized, controlled crossover study, normoxia (air exposure for 50 min before sleep and sham stimulation for 6 h during sleep), IH (5 repeats of 5 min 10-12 % O2 alternating with 5 min air for 50 min, and sham stimulation for 6 h), ITES (air exposure for 50 min and 6 repeats of 30 min transcutaneous electrical stimulation alternating with 30 min of sham stimulation for 6 h), and IH&ITES (10-12 % O2 alternating with air for 50 min and transcutaneous electrical stimulation alternating with sham stimulation for 6 h) were administered to patients with OSA over four single-night sessions. The primary endpoint was difference in OSA severity between the interventions according to apnea-hypopnea index (AHI) and oxygen desaturation index (ODI). The efficacy was response to IH, ITES, IH&ITES defined as a ≥50 % reduction in AHI compared with normoxia. Twenty participants (17 male, 3 female) completed the trial. The median (IQR) AHI decreased from 14.5 (10.8, 17.5) events/h with normoxia to 6.9 (3.9, 14.8) events/h with IH (p=0.020), 5.7 (3.4, 9.1) events/h with ITES (p=0.001), and 3.5 (1.8, 6.4) events/h with IH&ITES (p=0.001). AHI was significantly different between IH and IH&ITES (p=0.042) but not between ITES and IH&ITES (p=0.850). For mild-moderate OSA (n=17), IH, ITES, and IH&ITES had a significant effect on AHI (p=0.013, p=0.001, p=0.001, respectively) compared with normoxia, but there were no differences in post hoc pairwise comparisons between intervention groups. No serious adverse events were observed. In conclusion, IH, ITES, and IH&ITES significantly reduced OSA severity. IH&ITES showed better efficacy in mild-moderate OSA than IH and was comparable to ITES. Our data do not support recommending IH&ITES over ITES for OSA.

Validation of a Portable Respiratory Monitoring System for the Diagnosis of Obstructive Sleep Apnea in Patients with Chronic Obstructive Pulmonary Disease: A Crossectional Study

Introduction  Portable respiratory monitoring (PM) has been used to diagnose obstructive sleep apnea (OSA) in the general population. However, its validation in patients with both OSA and chronic obstructive pulmonary disease (COPD), remains unclear. Objective  The aim of the study was to validate PM for the diagnosis of OSA in patients with COPD. Materials and Methods  In this crossectional study, COPD patients were submitted simultaneously to polysomnography (PSG) and PM. Moreover, the risk for OSA was verified by the Berlin, NoSAS, and STOP-BANG questionnaires. Sensitivity, specificity, positive predictive value, and negative predictive value for PM were calculated for the cutoff points of the hypopnea apnea index (AHI) of 5, 15, and 30 events/hour, as well as for the questionnaires. The Bland-Altman test and correlation analyses between the AHI of the PSG and PM were performed. Results  A total of 103 patients were evaluated (age 67.5 ± 9.9 years, 60% men). The STOP-BANG questionnaire had the highest sensitivity for OSA diagnosis, at 94.4% (72.7-99.9%). The sensitivity of PM decreased (87.0, 66.7, and 44.4%), and the specificity increased 40.0, 78.6, and 100.0%) as the AHI cutoff point increased from 5, 15, and 30. The Bland-Altman test indicated good limits of agreement (AHI = 5.5 ± 11.7 events/hour). Therefore, the AHI results of the PM showed a strong and positive correlation with those of the PSG (r = 0.70, p  < 0.0001). Conclusion  The PM test can be a useful tool for OSA diagnosis in patients with COPD.

Optimized Prescreen Survey Tool for Predicting Sleep Apnea Based on Deep Neural Network: Pilot Study

Obstructive sleep apnea (OSA) is one of the common sleep disorders related to breathing. It is important to identify an optimal set of questions among the existing questionnaires, using a data-driven approach, that can prescreen OSA with high sensitivity and specificity. The current study proposes reliable models that are based on machine learning techniques to predict the severity of OSA. A total of 66 participants consisted of 45 males and 21 females (average age = 52.4 years old; standard deviation ± 14.6). Participants were asked to fill out the questionnaire items. If the value of the Respiratory Disturbance Index (RDI) was more than 30, the participant was diagnosed with severe OSA. Several different modeling techniques were applied, including deep neural networks with a scaled principal component analysis (DNN-PCA), random forest (RF), Adaptive Boosting Classifier (ABC), Decision Tree Classifier (DTC), K-nearest neighbors classifier (KNC), and support vector machine classifier (SVMC). Among the participants, 27 participants were diagnosed with severe OSA (RDI > 30). The area under the receiver operating characteristic curve (AUROC) was used to evaluate the developed models. As a result, the AUROC values of DNN-PCA, RF, ABC, DTC, KNC, and SVMC models were 0.95, 0.62, 0.53, 0.53, 0.51, and 0.78, respectively. The highest AUROC value was found in the DNN-PCA model with a sensitivity of 0.95, a specificity of 0.75, a positive predictivity of 0.95, an F1 score of 0.95, and an accuracy of 0.95. The DNN-PCA model outperforms the existing screening questionnaires, scores, and other models.

Sleep Disordered Breathing and Neurocognitive Disorders

Sleep-disordered breathing (SDB), which includes conditions such as obstructive sleep apnea (OSA) and central sleep apnea (CSA), is an independent risk factor for cerebral small vessel disease (CSVD), stroke, heart failure, arrhythmias, and other cardiovascular disorders. The influence of OSA on brain structure and cognitive function has become an essential focus in the heart-brain axis, given its potential role in developing neurocognitive abnormalities. In this review, we found that OSA plays a significant role in the cardio-neural pathway that leads to the development of cerebral small vessel disease and neurocognitive decline. Although data is still limited on this topic, understanding the critical role of OSA in the heart-brain axis could lead to the utilization of imaging modalities to simultaneously identify early signs of pathology in both organ systems based on the known OSA-driven pathological pathways that result in a disease state in both the cardiovascular and cerebrovascular systems. This narrative review aims to summarize the current link between OSA and neurocognitive disorders, cardio-neural pathophysiology, and the treatment options available for patients with OSA-related neurocognitive disorders.

Assessment and management of continuous positive airway pressure therapy in patient with obstructive sleep apnea

Obstructive sleep apnea (OSA) causes excessive daytime sleepiness, impaired daytime functioning, and an increased risk of cardiovascular diseases. Continuous positive airway pressure (CPAP) is a highly effective therapy for moderate to severe OSA. Although CPAP adherence is commonly assessed using a 4-hthreshold, determining the optimal usage time based on clinical outcomes is crucial. While subjective sleepiness often improves with ≥4 h of CPAP usage, an extended duration (≥6 h) may be necessary to impact objective sleepiness. CPAP demonstrated a modest yet clinically meaningful dose-dependent effect on lowering blood pressure. For patients seeking antihypertensive benefits from CPAP therapy, the goal should extend beyond 4 h of use to maximize the therapeutic impact. Recognizing individual variations in sleep duration and responses to CPAP therapy is essential. The adoption of 'individualized goals for CPAP use,' outlining target times for specific outcomes, should also consider an individual's total sleep duration, including periods without CPAP. The impact of CPAP on clinical outcomes may vary, even with the same duration of CPAP use, depending on the period without CPAP use, particularly during the first or second half of sleep. Patients who remove or initiate CPAP midway or have a low CPAP usage frequency may require different forms of guidance. Tailoring patient education to address CPAP usage patterns may be necessary to enhanced satisfaction, self-efficacy, and adherence to therapy. Management of CPAP treatment should be personalized to meet individual needs and adapted based on specific response patterns for achieving treatment efficacy.

Impact of obstructive sleep apnoea on cardiovascular outcomes and mortality in young adults with congenital heart anomalies: insights from the national inpatient sample (2019)

BACKGROUND

Obstructive sleep apnoea is a common sleep disorder, and adult congenital heart disease (CHD) is also a significant burden on the population. Early diagnosis and treatment are important for improving quality of life and reducing the risk of health complications. The limited research on obstructive sleep apnoea and adult CHD highlights the need for further investigation into the relationship between these two conditions and the mechanisms underlying this relationship.

METHOD

We used NIS 2019 database to identify adult CHD admissions aged 18-44 years and assess the impact of obstructive sleep apnoea on all-cause mortality, dysrhythmia, and stroke. A propensity-matched cohort of individuals with and without obstructive sleep apnoea was obtained, and the outcomes were assessed using multivariable analysis and compared in terms of resource utilisation.

RESULTS

Of the 41,950 young adult CHD admissions, 6.3% (n = 2630) had obstructive sleep apnoea. The obstructive sleep apnoea+ (n = 2590) and obstructive sleep apnoea- (n = 2590) cohorts were comparable in terms of median age (35 years) and were predominantly male (63.1% versus 62.5%). The obstructive sleep apnoea+ cohort had a higher frequency of risk factors like chronic obstructive pulmonary disease, hypothyroidism, and prior venous thromboembolism than the obstructive sleep apnoea cohort. We found significant association of obstructive sleep apnoea with dysrhythmia (adjusted odds ratio 2.99, 95% confidence interval 2.13-4.19, p < 0.001), but no significant impact on the risk of all-cause mortality or stroke. The obstructive sleep apnoea+ cohort also had higher transfers to short-term facilities, prolonged stays, and higher charges (p < 0.001).

CONCLUSION

Our study provides important insights into relationship between obstructive sleep apnoea and adult CHD and highlights the need for further investigation into the impact of obstructive sleep apnoea on individuals with adult CHD.

Advancements in the neurocirculatory reflex response to hypoxia

Hypoxia is a pivotal factor in the pathophysiology of various clinical conditions, including obstructive sleep apnea, which has a strong association with cardiovascular diseases like hypertension, posing significant health risks. Although the precise mechanisms linking hypoxemia-associated clinical conditions with hypertension remains incompletely understood, compelling evidence suggests that hypoxia induces plasticity of the neurocirculatory control system. Despite variations in experimental designs and the severity, frequency, and duration of hypoxia exposure, evidence from animal and human models consistently demonstrates the robust effects of hypoxemia in triggering reflex-mediated sympathetic activation. Both acute and chronic hypoxia alters neurocirculatory regulation and, in some circumstances, leads to sympathetic outflow and elevated blood pressures that persist beyond the hypoxic stimulus. Dysregulation of autonomic control could lead to adverse cardiovascular outcomes and increase the risk of developing hypertension.

Obstructive sleep apnea, coronary calcification and arterial stiffness in patients with diabetic kidney disease

BACKGROUND AND AIMS

Obstructive sleep apnea (OSA) may accelerate arterial calcification, but the relation remains unexplored in diabetic kidney disease (DKD). We examined the associations between OSA, coronary calcification and large artery stiffness in patients with DKD and reduced renal function.

METHODS

Patients with type 2 diabetes, estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 and urine albumin-creatinine ratio (UACR) > 30 mg/g were tested for OSA quantified by the apnea-hypopnea index (AHI, events/hour). Patients without OSA (AHI< 5) were compared to patients with moderate (AHI 15-29) or severe (AHI ≥30) OSA and underwent computed tomography angiography with coronary Agatston scoring (CAS) to quantify coronary calcification. Arterial stiffness was determined as carotid-femoral pulse wave velocity (PWV).

RESULTS

Among 114 patients with acceptable AHI recordings had 43 no OSA, 33 mild OSA and 38 moderate-severe OSA. Mean age of the 74 patients completing the study was 71.5 ± 9.4 years (73% males), eGFR 32.2 ± 12.3 ml/min/1.73 m2 and UACR 533 (192-1707) mg/g. CAS (ln-transformed) was significantly higher in patients with OSA compared to patients without (6.6 ± 1.7 vs. 5.6 ± 2.4, p = 0.04), and the same was observed for PWV (11.9 ± 2.7 vs. 10.5 ± 2.2 m/s, p = 0.02). In multivariable linear regression analyses adjusted for sex, age, body mass index, UACR, and mean arterial pressure, moderate-severe OSA remained significantly associated with PWV but not with CAS. Dominance analysis revealed OSA as the third and second most important factor relative to CAS and PWV respectively.

CONCLUSIONS

In DKD patients, moderate-severe OSA is a significant predictor of arterial stiffness but is not independently associated with coronary calcification.

Identifying clusters of patient comorbidities associated with obstructive sleep apnea using electronic health records

STUDY OBJECTIVES

The objectives of this study were to understand the relative comorbidity burden of obstructive sleep apnea (OSA), determine whether these relationships were modified by sex or age, and identify patient subtypes defined by common comorbidities.

METHODS

Cases with OSA and noncases (controls) were defined using a validated electronic health record (EHR)-based phenotype and matched for age, sex, and time period of follow-up in the EHR. We compared prevalence of the 20 most common comorbidities between matched cases and controls using conditional logistic regression with and without controlling for body mass index. Latent class analysis was used to identify subtypes of OSA cases defined by combinations of these comorbidities.

RESULTS

In total, 60,586 OSA cases were matched to 60,586 controls (from 1,226,755 total controls). Patients with OSA were more likely to have each of the 20 most common comorbidities compared with controls, with odds ratios ranging from 3.1 to 30.8 in the full matched set and 1.3 to 10.2 after body mass index adjustment. Associations between OSA and these comorbidities were generally stronger in females and patients with younger age at diagnosis. We identified 5 distinct subgroups based on EHR-defined comorbidities: High Comorbidity Burden, Low Comorbidity Burden, Cardiovascular Comorbidities, Inflammatory Conditions and Less Obesity, and Inflammatory Conditions and Obesity.

CONCLUSIONS

Our study demonstrates the power of leveraging the EHR to understand the relative health burden of OSA, as well as heterogeneity in these relationships based on age and sex. In addition to enrichment for comorbidities, we identified 5 novel OSA subtypes defined by combinations of comorbidities in the EHR, which may be informative for understanding disease outcomes and improving prevention and clinical care. Overall, this study adds more evidence that OSA is heterogeneous and requires personalized management.

CITATION

Te TT, Keenan BT, Veatch OJ, Boland MR, Hubbard RA, Pack AI. Identifying clusters of patient comorbidities associated with obstructive sleep apnea using electronic health records. J Clin Sleep Med. 2024;20(4):521-533.

Associations of sleep disorders with all-cause MCI/dementia and different types of dementia - clinical evidence, potential pathomechanisms and treatment options: A narrative review

Due to worldwide demographic change, the number of older persons in the population is increasing. Aging is accompanied by changes of sleep structure, deposition of beta-amyloid (Aß) and tau proteins and vascular changes and can turn into mild cognitive impairment (MCI) as well as dementia. Sleep disorders are discussed both as a risk factor for and as a consequence of MCI/dementia. Cross-sectional and longitudinal population-based as well as case-control studies revealed sleep disorders, especially sleep-disorderded breathing (SDB) and excessive or insufficient sleep durations, as risk factors for all-cause MCI/dementia. Regarding different dementia types, SDB was especially associated with vascular dementia while insomnia/insufficient sleep was related to an increased risk of Alzheimer's disease (AD). Scarce and still inconsistent evidence suggests that therapy of sleep disorders, especially continuous positive airway pressure (CPAP) in SDB, can improve cognition in patients with sleep disorders with and without comorbid dementia and delay onset of MCI/dementia in patients with sleep disorders without previous cognitive impairment. Regarding potential pathomechanisms via which sleep disorders lead to MCI/dementia, disturbed sleep, chronic sleep deficit and SDB can impair glymphatic clearance of beta-amyloid (Aß) and tau which lead to amyloid deposition and tau aggregation resulting in changes of brain structures responsible for cognition. Orexins are discussed to modulate sleep and Aß pathology. Their diurnal fluctuation is suppressed by sleep fragmentation and the expression suppressed at the point of hippocampal atrophy, contributing to the progression of dementia. Additionally, sleep disorders can lead to an increased vascular risk profile and vascular changes such as inflammation, endothelial dysfunction and atherosclerosis which can foster neurodegenerative pathology. There is ample evidence indicating that changes of sleep structure in aging persons can lead to dementia and also evidence that therapy of sleep disorder can improve cognition. Therefore, sleep disorders should be identified and treated early.

Effect of Continuous Positive Airway Pressure on Incident Frailty in Elderly Patients with Obstructive Sleep Apnea: A Study Based on Propensity Score Matching

Background

The concomitant rise in the prevalence of obstructive sleep apnea (OSA) and frailty among the elderly population has been linked to an increase in mortality rates. Despite continuous positive airway pressure (CPAP) being the gold standard treatment for OSA, its impact on incident frailty remains inadequately explored.

Methods

In this cohort study, we analyzed data from 1290 patients diagnosed with OSA, aged 60 years and older. A subset of 71 patients who demonstrated high adherence to CPAP therapy were categorized as the CPAP group. Propensity score matching (PSM) was employed at a 1:4 ratio, matching for variables such as age, gender, body mass index (BMI), and sleep apnea-hypopnea index (AHI), to establish a non-CPAP group for comparison. The FRAIL scale was utilized to evaluate the frailty status of participants. Logistic regression analysis examined the relationship between CPAP therapy and incident frailty, as well as its individual components, in elderly patients with OSA.

Results

During a median follow-up period of 52 months, incident frailty was observed in 70 patients (19.7%). Patients with OSA receiving CPAP therapy exhibited a lower incidence of frailty compared to those not receiving CPAP (11.26% vs 21.83%, P=0.045). In the multivariate model, CPAP therapy was significantly correlated with a reduced risk of incident frailty (OR = 0.36, 95% CI, 0.15-0.88; P = 0.025). Subcomponent analyses revealed that CPAP was associated with a lower risk of fatigue (OR=0.35, 95% CI, 0.19-0.63; P < 0.001), resistance (OR = 0.32, 95% CI, 0.14-0.74; P=0.008), and weight loss (OR = 0.38, 95% CI, 0.19-0.75; P = 0.007).

Conclusion

CPAP therapy was associated with a reduced risk of incident frailty among elderly patients with OSA.

The pathogenesis of OSA-related hypertension: what are the determining factors?

Sleep-disordered breathing has a relatively high prevalence, which varies from 3-7% in males and from 2-5% in females in the adult population. Studies published in the literature have shown that sleep apnea is closely related to an increased risk of developing various pathologies, among which arterial hypertension stands out. The prevalence of hypertension in patients suffering from obstructive sleep apnea (OSA) ranges from 35-80% and appears to be related to OSA severity. Approximately 40-50% of patients affected by hypertension are also affected by OSA and this association seems to be stronger in young and middle-aged adults (<50 years of age). The primary objective of this narrative review is to provide an update on what are the main contributing comorbidities to the development of a hypertensive state in patients suffering from OSA, an independent risk factor for diurnal hypertension, implicated as a risk factor for the first stroke, recurrent stroke, and post-stroke mortality. There are a lot of factors that contribute to developing a hypertensive state in OSA patients, some more decisive, others less. More evidence from longitudinal studies is needed on the impact of OSA on cardiovascular risk in females, on the causal link between OSA and arterial hypertension or metabolic diseases, like diabetes and glucose intolerance, and the effect of different kinds of OSA treatment.

Review and perspective on sleep-disordered breathing research and translation to clinics

Sleep-disordered breathing, ranging from habitual snoring to severe obstructive sleep apnea, is a prevalent public health issue. Despite rising interest in sleep and awareness of sleep disorders, sleep research and diagnostic practices still rely on outdated metrics and laborious methods reducing the diagnostic capacity and preventing timely diagnosis and treatment. Consequently, a significant portion of individuals affected by sleep-disordered breathing remain undiagnosed or are misdiagnosed. Taking advantage of state-of-the-art scientific, technological, and computational advances could be an effective way to optimize the diagnostic and treatment pathways. We discuss state-of-the-art multidisciplinary research, review the shortcomings in the current practices of SDB diagnosis and management in adult populations, and provide possible future directions. We critically review the opportunities for modern data analysis methods and machine learning to combine multimodal information, provide a perspective on the pitfalls of big data analysis, and discuss approaches for developing analysis strategies that overcome current limitations. We argue that large-scale and multidisciplinary collaborative efforts based on clinical, scientific, and technical knowledge and rigorous clinical validation and implementation of the outcomes in practice are needed to move the research of sleep-disordered breathing forward, thus increasing the quality of diagnostics and treatment.

Positive airway pressure therapy adherence and outcomes in obstructive sleep apnea: An exploratory longitudinal retrospective randomized chart review

Background

Positive airway pressure (PAP) therapy is prescribed to patients with obstructive sleep apnea (OSA). A commonly used definition for PAP therapy adherence is based upon the minimum requirements to receive Medicare coverage in the US, defined as PAP usage of four or more hours per night on 70 percent of nights for at least 30 consecutive days. However, little evidence exists to support this definition for PAP therapy adherence. Therefore, the present study sought to determine the efficacy of the present definition of PAP therapy adherence on longitudinal outcomes in patients with OSA, using objectively measured PAP device usage time.

Methods

An exploratory longitudinal, retrospective, randomized chart review was done to assess clinical outcomes between patients with OSA who were defined as PAP therapy adherent (n=50) and non-adherent (n=50) during an eight-year observation period.

Results

No significant differences were shown between groups for mortality, hospitalizations, or development of co-morbidities during the observation period. However, logistic regression showed significantly higher odds of adherence in male patients compared to female patients (OR=8.519; 95%CI=1.301-55.756; p=0.025) and significantly lower odds of adherence in patients with higher normal (OR=0.039; 95%CI=0.005-0.392; p=0.003), mild excessive (OR=0.039; 95%CI=0.003-0.517; p=0.014), and severe excessive (OR=0.088; 95%CI=0.012-0.635; p=0.016) daytime sleepiness compared to patients with lower normal daytime sleepiness. An increasing number of hospitalizations also corresponded with a significant decrease in odds of being adherent (OR=0.741; 95%CI=0.551-0.995; p=0.046).

Conclusion

The present study supports a steadily growing body of literature calling for more consideration and evidence to support a definition of PAP therapy adherence that is clinically meaningful.

Aging and atrial fibrillation: A vicious circle

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmia observed in clinical practice. Its prevalence increases dramatically with advancing age. This review article discusses the recent advances in studies investigating the relationship between aging and AF and the possible underlying mechanisms.

Regional associations between inspiratory tongue dilatory movement and genioglossus activity during wakefulness in people with obstructive sleep apnoea

Inspiratory tongue dilatory movement is believed to be mediated via changes in neural drive to genioglossus. However, this has not been studied during quiet breathing in humans. Therefore, this study investigated this relationship and its potential role in obstructive sleep apnoea (OSA). During awake supine quiet nasal breathing, inspiratory tongue dilatory movement, quantified with tagged magnetic resonance imaging, and inspiratory phasic genioglossus EMG normalised to maximum EMG were measured in nine controls [apnoea-hypopnea index (AHI) ≤5 events/h] and 37 people with untreated OSA (AHI >5 events/h). Measurements were obtained for 156 neuromuscular compartments (85%). Analysis was adjusted for nadir epiglottic pressure during inspiration. Only for 106 compartments (68%) was a larger anterior (dilatory) movement associated with a higher phasic EMG [mixed linear regression, beta = 0.089, 95% CI [0.000, 0.178], t(99) = 1.995, P = 0.049, hereafter EMG↗/mvt↗]. For the remaining 50 (32%) compartments, a larger dilatory movement was associated with a lower phasic EMG [mixed linear regression, beta = -0.123, 95% CI [-0.224, -0.022], t(43) = -2.458, P = 0.018, hereafter EMG↘/mvt↗]. OSA participants had a higher odds of having at least one decoupled EMG↘/mvt↗ compartment (binary logistic regression, odds ratio [95% CI]: 7.53 [1.19, 47.47] (P = 0.032). Dilatory tongue movement was minimal (>1 mm) in nearly all participants with only EMG↗/mvt↗ compartments (86%, 18/21). These results demonstrate that upper airway dilatory mechanics cannot be predicted from genioglossus EMG, particularly in people with OSA. Tongue movement associated with minimal genioglossus activity suggests co-activation of other airway dilator muscles. KEY POINTS: Inspiratory tongue movement is thought to be mediated through changes in genioglossus activity. However, it is unknown if this relationship is altered by obstructive sleep apnoea (OSA). During awake supine quiet nasal breathing, inspiratory tongue movement, quantified with tagged magnetic resonance imaging (MRI), and inspiratory phasic genioglossus EMG normalised to maximum EMG were measured in four tongue compartments of people with and without OSA. Larger tongue anterior (dilatory) movement was associated with higher phasic genioglossus EMG for 68% of compartments. OSA participants had an ∼7-times higher odds of having at least one compartment for which a larger anterior tongue movement was not associated with a higher phasic EMG than controls. Therefore, higher genioglossus phasic EMG does not consistently translate into tongue dilatory movement, particularly in people with OSA. Large dilatory tongue movements can occur despite minimal genioglossus inspiratory activity, suggesting co-activation of other pharyngeal muscles.

Carotid body contribution to the physio-pathological consequences of intermittent hypoxia: role of nitro-oxidative stress and inflammation

Obstructive sleep apnoea (OSA), characterized by chronic intermittent hypoxia (CIH), is considered to be an independent risk for hypertension. The pathological cardiorespiratory consequences of OSA have been attributed to systemic oxidative stress, inflammation and sympathetic overflow induced by CIH, but an emerging body of evidence indicates that a nitro-oxidative and pro-inflammatory milieu within the carotid body (CB) is involved in the potentiation of CB chemosensory responses to hypoxia, which contribute to enhance the sympathetic activity. Accordingly, autonomic and cardiovascular alterations induced by CIH are critically dependent on an abnormally heightened CB chemosensory input to the nucleus of tractus solitarius (NTS), where second-order neurons project onto the rostral ventrolateral medulla (RVLM), activating pre-sympathetic neurons that control pre-ganglionic sympathetic neurons. CIH produces oxidative stress and neuroinflammation in the NTS and RVLM, which may contribute to the long-term irreversibility of the CIH-induced alterations. This brief review is mainly focused on the contribution of nitro-oxidative stress and pro-inflammatory molecules on the hyperactivation of the hypoxic chemoreflex pathway including the CB and the brainstem centres, and whether the persistence of autonomic and cardiorespiratory alterations may depend on the glial-related neuroinflammation induced by the enhanced CB chemosensory afferent input.

Severity of sleep apnea impairs adipose tissue insulin sensitivity in individuals with obesity and newly diagnosed obstructive sleep apnea

Introduction

Obstructive sleep apnea (OSA) is a common sleep disorder associated with increased risk for the development of type 2 diabetes. While studies have examined the effects of sleep on whole-body insulin sensitivity, little is known about the effects of sleep on adipose tissue insulin sensitivity in patients with OSA. We analyzed if the severity of OSA, measured by apnea-hypopnea index (AHI), is associated with adipose tissue insulin sensitivity.

Methods

We examined the relationship between sleep parameters and adipose tissue insulin sensitivity in non-diabetic participants with obesity and newly diagnosed OSA who underwent overnight polysomnography and a 2 h oral glucose tolerance test during which circulating free fatty acids were measured. In total, 16 non-diabetic participants with obesity and newly diagnosed OSA (sex, 81.3% males; mean age, 50.9 ± 6.7 y; BMI, 36.5 ± 2.9 kg/m2; AHI, 43 ± 20 events/h) were included in the analysis.

Results

In our study participants, AHI is inversely associated with free-fatty acid suppression during oral glucose challenge (R = -0.764, p = 0.001). This relationship persisted even after statistical adjustment for age (R = -0.769, p = 0.001), body mass index (R = -0.733, p = 0.002), waist-to-hip ratio (R = -0.741, p = 0.004), or percent body fat mass (R = -0.0529, p = 0.041). Furthermore, whole-body insulin sensitivity as determined by the Matsuda index was associated with percent REM sleep (R = 0.552, p = 0.027) but not AHI (R = -0.119, p = 0.660).

Conclusion

In non-diabetic patients with OSA, the severity of sleep apnea is associated with adipose tissue insulin sensitivity but not whole-body insulin sensitivity. The impairments in adipose tissue insulin sensitivity may contribute to the development of type 2 diabetes.

Screening obstructive sleep apnea patients via deep learning of knowledge distillation in the lateral cephalogram

The lateral cephalogram in orthodontics is a valuable screening tool on undetected obstructive sleep apnea (OSA), which can lead to consequences of severe systematic disease. We hypothesized that a deep learning-based classifier might be able to differentiate OSA as anatomical features in lateral cephalogram. Moreover, since the imaging devices used by each hospital could be different, there is a need to overcome modality difference of radiography. Therefore, we proposed a deep learning model with knowledge distillation to classify patients into OSA and non-OSA groups using the lateral cephalogram and to overcome modality differences simultaneously. Lateral cephalograms of 500 OSA patients and 498 non-OSA patients from two different devices were included. ResNet-50 and ResNet-50 with a feature-based knowledge distillation models were trained and their performances of classification were compared. Through the knowledge distillation, area under receiver operating characteristic curve analysis and gradient-weighted class activation mapping of knowledge distillation model exhibits high performance without being deceived by features caused by modality differences. By checking the probability values predicting OSA, an improvement in overcoming the modality differences was observed, which could be applied in the actual clinical situation.

NADPH Oxidases and Oxidative Stress in the Pathogenesis of Atrial Fibrillation

Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and its prevalence increases with age. The irregular and rapid contraction of the atria can lead to ineffective blood pumping, local blood stasis, blood clots, ischemic stroke, and heart failure. NADPH oxidases (NOX) and mitochondria are the main sources of reactive oxygen species in the heart, and dysregulated activation of NOX and mitochondrial dysfunction are associated with AF pathogenesis. NOX- and mitochondria-derived oxidative stress contribute to the onset of paroxysmal AF by inducing electrophysiological changes in atrial myocytes and structural remodeling in the atria. Because high atrial activity causes cardiac myocytes to expend extremely high energy to maintain excitation-contraction coupling during persistent AF, mitochondria, the primary energy source, undergo metabolic stress, affecting their morphology, Ca2+ handling, and ATP generation. In this review, we discuss the role of oxidative stress in activating AF-triggered activities, regulating intracellular Ca2+ handling, and functional and anatomical reentry mechanisms, all of which are associated with AF initiation, perpetuation, and progression. Changes in the extracellular matrix, inflammation, ion channel expression and function, myofibril structure, and mitochondrial function occur during the early transitional stages of AF, opening a window of opportunity to target NOX and mitochondria-derived oxidative stress using isoform-specific NOX inhibitors and mitochondrial ROS scavengers, as well as drugs that improve mitochondrial dynamics and metabolism to treat persistent AF and its transition to permanent AF.

Anthropometric Determinants of Autonomic Control in Obstructive Sleep Apnea: A Large-Scale Study

OBJECTIVE

Autonomic dysfunction is an independent risk factor for cardiovascular disease (CVD). Both obesity and obstructive sleep apnea (OSA) are associated with heart rate variability (HRV) (a hall marker of sympathetic arousal) and increased risk of CVD. This study aims to investigate whether anthropometric parameters could predict reduced HRV in adult OSA during wakefulness.

STUDY DESIGN

Cross-sectional study.

SETTING

Sleep center of Shanghai Jiao Tong University Affiliated Sixth Hospital from 2012 to 2017.

METHODS

Total of 2134 subjects (503 non-OSA and 1631 OSA) were included. Anthropometric parameters were recorded. HRV was recorded during a 5-minute wakefulness period and analyzed by using time-domain method and frequency-domain method. Multiple step-wise linear regressions were performed to determine significant predictors of HRV with and without adjustments. Multiplicative interactions between gender, OSA, and obesity on HRV were also determined and evaluated.

RESULTS

Waist circumference (WC) was significant negative determinant of root mean square of successive NN intervals (β = -.116, p < .001) and high-frequency power (β = -.155, p < .001). Age was the strongest determining factor of HRV. Significant multiplicative interactions between obesity and OSA on HRV, gender, and obesity on cardiovascular parameters were observed.

CONCLUSION

Anthropometric parameters could predict reduced HRV during wakefulness in patients with OSA, especially WC was the strongest influenceable factor. Obesity and OSA had significant multiplicative interaction on HRV. Gender and obesity had significant multiplicative interaction on cardiovascular parameters. Early intervention for obesity, especially centripetal obesity, may improve reduction of autonomic function and risk of CVD.

Effects of obstructive sleep apnea during rapid eye movement sleep on cardiac autonomic dysfunction: Results from the Shanghai sleep health study cohort

In our large-scale study, the correlation between obstructive sleep apnea (OSA) related to rapid eye movement (REM) sleep and cardiac autonomic dysfunction was assessed by standard polysomnography (PSG). Cardiac autonomic dysfunction was evaluated by the measurement of heart rate variability (HRV). The cardiovascular disease (CVD) risk was determined using the cross-sectional prevalence of CVD and its overall 10 year risk according to the Framingham risk score (FRS). 4152 individuals were included in the study. A higher apnea-hypopnea index during REM sleep (AHIREM ) was correlated with increased CVD risk. The adjusted odds ratios (95% CIs) for CVD prevalence and its high 10 year risk in participants having severe OSA during REM sleep (AHIREM  ≥30 events/h) were 1.452 (1.012-2.084) and 1.904 (1.470-2.466) in the demographic adjusted model and 1.175 (0.810-1.704) and 1.716 (1.213-2.427) in the multivariate adjusted model, respectively, compared with the group with a AHIREM of <5 events/h. Fully adjusted multivariate linear regression models showed the independent association between AHIREM and a more elevated ratio of low-frequency and high-frequency (LF/HF) and LF in normalised units [LF (n.u.)] (P = 0.042, P = 0.027 in all participants and P = 0.033, P = 0.029 in participants with AHI during non-REM sleep <5 events/h, respectively). Mediation analysis demonstrated that OSA during REM sleep and CVD risk was significantly mediated by LF/HF and LF (n.u.). OSA during REM sleep may be a marker behind CVD risk because it promotes cardiac autonomic dysfunction.

Differences in the effects of orthodontic treatment on airway-craniocervical functional environment in adult and adolescent patients with skeletal class II high-angle: a retrospective pilot study

INTRODUCTION

This retrospective cohort study aimed to compare the change in upper airway and craniocervical posture after orthodontic treatment between adolescent and adult patients with Class II high-angle malocclusion.

METHODS

A total of 12 adolescent (mean ± standard deviation age = 13.0 ± 2.0 years) and 12 adult patients with Class II high-angle malocclusion (mean ± standard deviation age = 23.7 ± 6.4 years) were selected in this study. The lateral cephalograms and cone beam computed tomography images of adolescent and adult patients were taken before and after treatment, which can be employed to evaluate the variables of craniofacial morphology, upper airway, and craniocervical posture through paired t tests, respectively. An independent sample t test was performed to observe the differences between two groups after orthodontic intervention. For adults and adolescents, the correlation between craniofacial morphology, upper airway, and craniocervical posture was determined through Pearson correlation analysis.

RESULTS

In all subjects, the improvements in vertical and sagittal facial morphology after treatment were observed. Anterior and inferior movements of the hyoid bone, an increase of upper airway dimension, posterior tipping of the head and a reduction of cervical inclination in the lower and middle segments post-treatment were identified in adolescence (P < 0.05). Adults displayed anterior movements of the hyoid bone, whereas no significant difference was observed in upper airway dimension and craniocervical posture (P < 0.05). Notable differences were identified in the change of hyoid position and airway volume between two groups (P > 0.05). Mandibular plane inclination, growth pattern, occlusal plane inclination, and chin position were all significantly correlated with craniocervical posture in adolescent patients. Besides, the mandibular growth pattern and chin position in adult patients were significantly correlated with craniocervical posture (P < 0.05).

CONCLUSIONS

Orthodontic treatment is capable of enhancing the facial profile of patients with skeletal class II high-angle while improving their upper airway morphology and craniocervical posture, where adolescents and adults differ substantially in that the former exhibit a more favorable alteration in the airway-craniocervical functional environment.

Peripheral arterial tonometry versus polysomnography in suspected obstructive sleep apnoea

BACKGROUND

Polysomnography (PSG) is the gold standard for the diagnosis of obstructive sleep apnoea (OSA). Home sleep apnoea testing with peripheral arterial tonometry (PAT) is a recommended diagnostic alternative for patients with an increased risk for OSA. In a large clinical cohort, we investigated concordance and predictors for discordance in diagnosing OSA using PAT and PSG, and three-year cardiovascular risk in patients with discordant OSA diagnosis.

METHODS

Retrospective monocentric cohort study. Patients with a PAT AHI ≥ 5/h followed by an in-hospital PSG within three months were included. All patients with a PAT AHI ≥ 5/h but a PSG AHI < 5/h were classified as discordant. Patients with PAT and PSG AHI ≥ 5/h were classified as concordant. To ascertain cardiovascular risk, major adverse cardiovascular events (MACE) were analyzed in discordant patients and sex, age, body mass index (BMI) and cardiovascular disease-matched concordant patients over a follow-up time of 3.1 ± 0.06 years.

RESULTS

A total of 940 patients, 66% male with an average age of 55 ± 0.4 years and BMI of 31 ± 0.2 kg/m² were included. Agreement in OSA diagnosis was observed in 80% of patients (55% in mild and 86% in moderate and severe OSA). Factors significantly associated with a discordant diagnosis were female sex, younger age and lower BMI, but not comorbidities. There was no significant difference in MACE (p = 0.920) between discordant patients (n = 155) and matched concordant patients (n = 274) with or without therapy.

CONCLUSIONS

Concordance between PAT and PSG diagnosis of sleep apnoea is good, particularly in moderate and severe OSA. Predictors for discordant results between PAT and PSG were age, sex and BMI. MACE risk is similar in those with OSA diagnosed by PAT or PSG.

Unobtrusive Sleep Position Classification Using a Novel Optical Tactile Sensor

Unobtrusive sleep position classification is essential for sleep monitoring and closed-loop intervention systems that initiate position changes. In this paper, we present a novel unobtrusive under-mattress optical tactile sensor for sleep position classification. The sensor uses a camera to track particles embedded in a soft silicone layer, inferring the deformation of the silicone and therefore providing information about the pressure and shear distributions applied to its surface.We characterized the sensitivity of the sensor after placing it under a conventional mattress and applying different weights (258 g, 500 g, 5000 g) on top of the mattress in various predefined locations. Moreover, we collected multiple recordings from a person lying in supine, lateral left, lateral right, and prone positions. As a proof-of-concept, we trained a neural network based on convolutional layers and residual blocks that classified the lying positions based on the images from the tactile sensor.We observed a high sensitivity of the optical tactile sensor: Even after placing the sensor below a conventional mattress, we were able to detect our lowest test weight of 258 g. Using the neural network, we were able to classify the four sleep positions, lateral left, lateral right, prone, and supine with a classification accuracy of 91.2 %.The high sensitivity of the sensor, as well as the good performance in the classification task, demonstrate the feasibility of using such a sensor in a robotic bed setup.Clinical Relevance- Positional Obstructive Sleep Apnea is highly prevalent across the general population. Today's gold standard treatment of using CPAP ventilation is often not accepted, leading to unwanted treatment cessations. Alternative treatments, such as positional interventions through robotic beds are highly promising. However, these beds require reliable detection of the lying position. In this paper, we present a novel, scalable and completely unobtrusive sensor that is concealed under the mattress while classifying sleeping positions with high accuracy.

Undiagnosed obstructive sleep apnea increases risk of hospitalization among a racially diverse group of older adults with comorbid cardiovascular disease

STUDY OBJECTIVES

Undiagnosed obstructive sleep apnea (OSA) is associated with increased risk for subsequent cardiovascular events, hospitalizations, and mortality. The primary objective of this study was to determine the association between undiagnosed OSA and subsequent hospitalizations among older adults with preexisting cardiovascular disease (CVD). A secondary objective was to determine the risk of 30-day hospital readmission associated with undiagnosed OSA among older adults with CVD.

METHODS

This was a retrospective cohort study of a 5% sample of Medicare administrative claims data for years 2006-2013. Beneficiaries aged 65 years and older diagnosed with CVD were included. Undiagnosed OSA was defined as the 12-month period prior to OSA diagnosis. A similar 12-month period among beneficiaries not diagnosed with OSA was used for the comparison group (no OSA). Our primary outcome was the first all-cause hospital admission. Among beneficiaries with a hospital admission, 30-day readmission was assessed for the first hospital admission only.

RESULTS

Among 142,893 beneficiaries diagnosed with CVD, 19,390 had undiagnosed OSA. Among beneficiaries with undiagnosed OSA, 9,047 (46.7%) experienced at least 1 hospitalization whereas 27,027 (21.9%) of those without OSA experienced at least 1 hospitalization. Following adjustment, undiagnosed OSA was associated with increased risk of hospitalization (odds ratio 1.82; 95% confidence interval 1.77, 1.87) relative to no OSA. Among beneficiaries with ≥ 1 hospitalization, undiagnosed OSA was associated with a smaller but significant effect in weighted models (odds ratio 1.18; 95% confidence interval 1.09, 1.27).

CONCLUSIONS

Undiagnosed OSA was associated with significantly increased risk of hospitalization and 30-day readmissions among older adults with preexisting CVD.

CITATION

Kirk J, Wickwire EM, Somers VK, Johnson DA, Albrecht JS. Undiagnosed obstructive sleep apnea increases risk of hospitalization among a racially diverse group of older adults with comorbid cardiovascular disease. J Clin Sleep Med. 2023;19(7):1175-1181.

Effect of positive airway pressure compliance on laryngopharyngeal reflux in obstructive sleep apnea patients

OBJECTIVES

To determine the effect of continuous positive airway pressure (CPAP) compliance on symptoms and signs of laryngopharyngeal reflux (LPR) in patients with obstructive sleep apnea (OSA).

RESULTS

Thirty patients were included. The participants were divided into good compliance (n = 21) and poor compliance (n = 9) groups. After 6-month CPAP treatment, the reflux symptom index score significantly decreased in both the good compliance group (20 (17,24) vs. 14 (10,18), p < 0.001) and the poor compliance group (21 (18,25) vs. 10 (5,16), p < 0.05). Reflux finding score was significantly reduced in both the good compliance group (8 (6,9) vs. 4 (3,5), p < 0.001) and the poor compliance group (6 (4,8) vs. 3 (2,4), p < 0.05). However, there were no statistically significant differences between the groups. CPAP treatment reduces the symptoms and signs of LPR. However, CPAP compliance does not correlate with improvement in LPR in patients with OSA.

Prediction of Sleep Apnea Events Using a CNN-Transformer Network and Contactless Breathing Vibration Signals

It is estimated that globally 425 million subjects have moderate to severe obstructive sleep apnea (OSA). The accurate prediction of sleep apnea events can offer insight into the development of treatment therapies. However, research related to this prediction is currently limited. We developed a covert framework for the prediction of sleep apnea events based on low-frequency breathing-induced vibrations obtained from piezoelectric sensors. A CNN-transformer network was utilized to efficiently extract local and global features from respiratory vibration signals for accurate prediction. Our study involved overnight recordings of 105 subjects. In five-fold cross-validation, we achieved an accuracy of 85.9% and an F1 score of 85.8%, which are 3.5% and 5.3% higher than the best-performed classical model, respectively. Additionally, in leave-one-out cross-validation, 2.3% and 3.8% improvements are observed, respectively. Our proposed CNN-transformer model is effective in the prediction of sleep apnea events. Our framework can thus provide a new perspective for improving OSA treatment modes and clinical management.

Contactless screening for sleep apnea with breathing vibration signals based on modified U-Net

BACKGROUND

Obstructive sleep apnea (OSA) is a chronic sleep disorder characterized by frequent cessations or reductions of breathing during sleep. Polysomnography (PSG) is a definitive diagnostic tool for OSA. The costly and obtrusive nature of PSG and poor access to sleep clinics have created a demand for accurate home-based screening devices.

METHODS

This paper proposes a novel OSA screening method based solely on breathing vibration signals with a modified U-Net, allowing patients to be tested at home. Sleep recordings over a whole night are collected in a contactless manner, and sleep apnea-hypopnea events are labeled by a deep neural network. The apnea-hypopnea index (AHI) calculated from events estimation is then used to screen for the apnea. The performance of the model is tested by event-based analysis and comparing the estimated AHI with the manually obtained values.

RESULTS

The accuracy and sensitivity of sleep apnea events detection are 97.5% and 76.4%, respectively. The mean absolute error of AHI estimation for the patients is 3.0 events/hour. The correlation between the ground truth AHI and predicted AHI shows an R² of 0.95. In addition, 88.9% of all participants are classified into correct AHI categories.

CONCLUSIONS

The proposed scheme has great potential as a simple screening tool for sleep apnea. It can accurately detect potential OSA and help the patients to be referred for differential diagnosis of home sleep apnea test (HSAT) or polysomnographic evaluation.

Increased P-wave dispersion in patients with obstructive sleep apnea syndrome: a meta-analysis

PURPOSE

Prolonged atrial conduction and inhomogeneous sinus impulse propagation may play a role in the initiation and maintenance of atrial tachyarrhythmias. Such a process could be reflected in inter-lead P-wave duration differences known as "P-wave dispersion" (PWD). Abnormal PWD may be related to obstructive sleep apnea syndrome (OSAS). A meta-analysis of the available publications was conducted.

METHODS

A MEDLINE, Web of Science, and Google Scholar search from 2000 to 2021 was performed. The keywords used for search were apnea AND "P wave dispersion." Case-control studies and surveys were selected as long as they included healthy subjects and subjects with diagnosed OSAS who did not have any other major health problems. PWD values and correlations between apnea-hypopnea indices (AHI) and PWD were used as outcome measures.

RESULTS

Ten studies met the inclusion creteria, encompassing 773 patients with OSAS and 347 healthy controls. The mean ages of the patients with OSAS ranged from 6.9 to 58.8 years. The estimated average Hedges's g standardized mean difference in PWD values was equal to 1.883 (95% CI: 1.140 to 2.626, p < 0.001). The estimated average Fisher r-to-z transformed correlation coefficient between AHI and PWD was equal to 0.530 (95% CI: 0.075 to 0.985, p = 0.0225). Meta-regression analysis failed to find statistically significant correlations between the effect sizes and the mean age, male proportion, and the body mass index in the OSAS groups.

CONCLUSION

OSAS is associated with increased PWD, which may predispose to atrial tachyarrythmias.

Comparison of clinical features and surgical outcomes between hypopnea- and apnea-predominant obstructive sleep apnea

OBJECTIVES

This study is aimed to investigate the differences in the clinical features and surgical outcomes between hypopnea- and apnea-predominant obstructive sleep apnea (OSA).

DESIGN

Cohort study.

SETTING

Single tertiary care centre.

PARTICIPANTS

This study included 190 patients with OSA who underwent multilevel upper airway surgery between September 2012 and September 2021. The patients were divided into two groups according to the proportion of each respiratory event: hypopnea-predominant (n = 102) and apnea-predominant (n = 88).

MAIN OUTCOME MEASURES

The primary outcome measure was the percentage improvement in the apnea-hypopnea index (AHI) from baseline AHI after surgery.

RESULTS

The apnea-predominant group included more male patients and had higher AHI, respiratory disturbance index (RDI) and oxygen desaturation index (ODI) than the hypopnea-predominant group. Both groups showed significant improvements in AHI, apnea index, RDI, supine AHI, REM AHI, non-REM AHI, ODI, lowest O₂ saturation and Epworth Sleepiness Scale scores following the surgery. Notably, hypopnea index increased after surgery in the apnea-predominant OSA group. Although the improvement in the absolute value of AHI by surgery was significantly greater in the apnea-predominant group than in the hypopnea-predominant group, the two groups showed no significant difference in the percentage improvement in AHI from baseline AHI.

CONCLUSION

Patients with apnea-predominant OSA had more severe disease than those with hypopnea-predominant OSA; however, surgical outcomes, as evaluated by percentage AHI improvement, were comparable between the two groups. In addition, multilevel upper airway surgery may induce the transition from apnea to hypopnea in patients with apnea-predominant OSA.

Clinical Characteristics and Surgical Outcomes of Obstructive Sleep Apnea Patients With Mixed Apnea Components

OBJECTIVE

This study was aimed to investigate clinical implications of mixed apnea (MA) in patients with obstructive sleep apnea (OSA), particularly whether surgical outcomes differ between OSA patients with and without MA events.

STUDY DESIGN

Retrospective cohort study.

SETTING

Single tertiary medical center.

METHODS

Eighty-eight patients with OSA who underwent multilevel upper airway surgery were included. Patients were divided into 2 groups according to the presence of MA events: "pure group" (n = 30) and "mixed group" (n = 58). The clinical characteristics and surgical outcomes were compared between the 2 groups.

RESULTS

The mixed group included more males (P = .020) and hypertensive patients (P = .009) and had a higher apnea-hypopnea index (AHI; P < .001) than the pure group. The surgical success rate was lower in the mixed group (29.3%) than in the pure group (73.3%; P < .001). Furthermore, the postoperative improvements in total AHI (P < .001), supine AHI (P < .001), and oxygen desaturation index (P = .006) were lower in the mixed group than in the pure group. Logistic regression analysis confirmed that the presence of MA (P = .002) was an independent predictor of poor surgical outcomes in patients with OSA.

CONCLUSION

OSA patients with MA showed different clinical features and poor surgical outcomes compared to those without MA. These results imply that OSA with MA components may have a distinct pathophysiology, and the presence of MA should be considered in the surgical treatment of OSA.

Sleep apnea and carotid atherosclerosis in the Multi-Ethnic Study of Atherosclerosis (MESA): leveraging state-of-the-art vascular imaging

PURPOSE

To further characterize the relationship between obstructive sleep apnea (OSA) and carotid atherosclerosis, we examined the structural and metabolic features of carotid plaque using hybrid 18-F-fluorodeoxyglucose (FDG) Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

We studied 46 individuals from the MESA-PET and MESA-Sleep ancillary studies. OSA was defined as an apnea hypopnea index [AHI] ≥ 15 events per hour (4% desaturation). PET/MRI was used to measure carotid plaque inflammation (using target-to-background-ratios [TBR]) and carotid wall thickness (CWT). Linear regression was used to assess the associations between OSA, CWT and TBR.

RESULTS

The mean age was 67.9 years (SD 8.53) and the mean BMI was 28.9 kg/m² (SD 4.47). There was a trend toward a higher mean CWT in the OSA (n = 11) vs. non-OSA group (n = 35), 1.51 vs. 1.41 (p = 0.098). TBR did not differ by OSA groups, and there was no significant association between OSA and carotid plaque inflammation (TBR) in adjusted analyses. Although there was a significant interaction between OSA and obesity, there were no statistically significant associations between OSA and vascular inflammation in stratified analysis by obesity.

CONCLUSION

Despite a trend toward a higher carotid wall thickness in OSA vs. non-OSA participants, we did not find an independent association between OSA and carotid plaque inflammation using PET/MRI in MESA. Our findings suggest that simultaneous assessments of structural and metabolic features of atherosclerosis may fill current knowledge gaps pertaining to the influence of OSA on atherosclerosis prevalence and progression.

Sleep Irregularity and Subclinical Markers of Cardiovascular Disease: The Multi-Ethnic Study of Atherosclerosis

Background Sleep irregularity has been linked to incident cardiovascular disease. Less is known about associations of sleep regularity with atherosclerosis. We examined cross-sectional associations of actigraphy-assessed sleep duration and sleep timing regularity with subclinical atherosclerosis in the community-based MESA (Multi-Ethnic Study of Atherosclerosis). Methods and Results MESA Sleep Ancillary Study participants (N=2032; mean age, 68.6±9.2 years; 37.9% White) completed 7-day wrist actigraphy. Participants underwent assessments of coronary artery calcium, carotid plaque presence, carotid intima-media thickness, and the ankle-brachial index. Sleep regularity was quantified by the 7-day with-in person SD of sleep duration and sleep onset timing. Relative risk regression models were used to calculate prevalence ratios and 95% CIs. Models are adjusted for demographics, cardiovascular disease risk factors, and other objectively assessed sleep characteristics including obstructive sleep apnea, sleep duration, and sleep fragmentation. After adjustment, compared with participants with more regular sleep durations (SD ≤60 minutes), participants with greater sleep duration irregularity (SD >120 minutes) were more likely to have high coronary artery calcium burden (>300; prevalence ratio, 1.33 [95% CI, 1.03-1.71]) and abnormal ankle-brachial index (<0.9; prevalence ratio, 1.75 [95% CI, 1.03-2.95]). Compared with participants with more regular sleep timing (SD ≤30 minutes), participants with irregular sleep timing (SD >90 minutes) were more likely to have high coronary artery calcium burden (prevalence ratio, 1.39 [95% CI, 1.07-1.82]). Associations persisted after adjustment for cardiovascular disease risk factors and average sleep duration, obstructive sleep apnea, and sleep fragmentation. Conclusions Sleep irregularity, particularly sleep duration irregularity, was associated with several measures of subclinical atherosclerosis. Sleep regularity may be a modifiable target for reducing atherosclerosis risk. Future investigation into cardiovascular risk reduction interventions targeting sleep irregularity may be warranted.

A Classifying Model of Obstructive Sleep Apnea Based on Heart Rate Variability in a Large Korean Population

BACKGROUND

The majority of patients with obstructive sleep apnea do not receive timely diagnosis and treatment because of the complexity of a diagnostic test. We aimed to predict obstructive sleep apnea based on heart rate variability, body mass index, and demographic characteristics in a large Korean population.

METHODS

Models of binary classification for predicting obstructive sleep apnea severity were constructed using 14 features including 11 heart rate variability variables, age, sex, and body mass index. Binary classification was conducted separately using apnea-hypopnea index thresholds of 5, 15, and 30. Sixty percent of the participants were randomly allocated to training and validation sets while the other forty percent were designated as the test set. Classifying models were developed and validated with 10-fold cross-validation using logistic regression, random forest, support vector machine, and multilayer perceptron algorithms.

RESULTS

A total of 792 (651 men and 141 women) subjects were included. The mean age, body mass index, and apnea-hypopnea index score were 55.1 years, 25.9 kg/m², and 22.9, respectively. The sensitivity of the best performing algorithm was 73.6%, 70.7%, and 78.4% when the apnea-hypopnea index threshold criterion was 5, 10, and 15, respectively. The prediction performances of the best classifiers at apnea-hypopnea indices of 5, 15, and 30 were as follows: accuracy, 72.2%, 70.0%, and 70.3%; specificity, 64.6%, 69.2%, and 67.9%; area under the receiver operating characteristic curve, 77.2%, 73.5%, and 80.1%, respectively. Overall, the logistic regression model using the apnea-hypopnea index criterion of 30 showed the best classifying performance among all models.

CONCLUSION

Obstructive sleep apnea was fairly predicted by using heart rate variability, body mass index, and demographic characteristics in a large Korean population. Prescreening and continuous treatment monitoring of obstructive sleep apnea may be possible simply by measuring heart rate variability.

Severe sleep apnea as a predictor of failure to respond to cardiac resynchronization therapy

BACKGROUND

The response to cardiac resynchronization therapy (CRT) is suboptimal in one-third of patients.

OBJECTIVES

The study aimed to evaluate the impact of sleep-disordered breathing (SDB) on the CRT-induced left ventricular (LV) reverse remodeling and response for CRT in patients with ischemic congestive heart failure (CHF).

METHODS

A total of 37 patients aged 65.43 years (SD 6.05), seven of whom were females, were treated with CRT according to class I European Society of Cardiology recommendations. Clinical evaluation, polysomnography, and contrast echocardiography were performed twice during the six-month follow-up (6M-FU) to assess the effect of CRT.

RESULTS

In 33 patients (89.1%), sleep-disordered breathing (SDB), predominantly central sleep apnea (70.3%) was observed. This include nine patients (24.3%) with an apnea-hypopnea index (AHI) of >30 events/hour. During the 6M-FU, 16 patients (47.1%) responded to CRT by reducing LV end-systolic volume index (LVESVi) by ≥15%. We stated a directly proportional linear relationship between AHI value and LV volume: LVESVi p = 0.004, and LV end-diastolic volume index p = 0.006.

CONCLUSIONS

Pre-existing severe SDB can impair the LV volumetric response to CRT even in an optimally selected group with class I indications for resynchronization, which may have an impact on long-term prognosis.

The Beneficial Effect of the Blockade of Stim-Activated TRPC-ORAI Channels on Vascular Remodeling and Pulmonary Hypertension Induced by Intermittent Hypoxia Is Independent of Oxidative Stress

Obstructive sleep apnea (OSA), a sleep breathing disorder featured by chronic intermittent hypoxia (CIH), is associated with pulmonary hypertension (PH). Rats exposed to CIH develop systemic and lung oxidative stress, pulmonary vascular remodeling, and PH and overexpress Stim-activated TRPC-ORAI channels (STOC) in the lung. Previously, we demonstrated that 2-aminoethyl-diphenylborinate (2-APB)-treatment, a STOC-blocker, prevents PH and the overexpression of STOC induced by CIH. However, 2-APB did not prevent systemic and pulmonary oxidative stress. Accordingly, we hypothesize that the contribution of STOC in the development of PH induced by CIH is independent of oxidative stress. We measured the correlation between right ventricular systolic pressure (RVSP) and lung malondialdehyde (MDA) with the gene expression of STOC and morphological parameters in the lung from control, CIH-treated, and 2-APB-treated rats. We found correlations between RVSP and increased medial layer and STOC pulmonary levels. 2-APB-treated rats showed a correlation between RVSP and the medial layer thickness, α-actin-ir, and STOC, whereas RVSP did not correlate with MDA levels in CIH and 2-APB-treated rats. CIH rats showed correlations between lung MDA levels and the gene expression of TRPC1 and TRPC4. These results suggest that STOC channels play a key role in developing CIH-induced PH that is independent from lung oxidative stress.