Mean Respiratory Disturbance Index Research Articles

Prevalence and predictors of sleep bruxism in patients withobstructive sleep apnea and the effect of positive airway pressure treatment.

Sleep bruxism (SB) is often found to co-exist with obstructive sleep apnea (OSA). However, there are no data on prevalence and risk factors of SB in patients withOSA patients regarding the effect of optimal positive airway pressure (PAP). This study aimed to study prevalence and risk factors of SB in OSA and to compare SB episodes during pre-treatment versus during optimal PAP therapy. This investigation was a retrospective study including randomly selected patients with OSA who underwent split-night polysomnography. Data were collected from August 2021 to October 2022. Clinical demographic data and SB data were analyzed. The association between SB episodes and obstructive respiratory events were manually reviewed. If most of the SB episodes were observed within 5s following obstructive respiratory events, SB was defined as SB associated with OSA. Comparison of SB index (SBI) was made between baseline portion of the study versus during optimal PAP. Among 100 patients enrolled, mean age was 50.8 ± 16.7yearsand 73 subject (73%) were male. Mean respiratory disturbance index (RDI) and mean nadir oxygen saturation were 52.4 ± 33.4 and 79.3 ± 11.2% respectively. During the baseline portion of the study, 49 patients (49%) had SBand 31 patients (31%) had severe SB (SBI ≥ 4). Sleep bruxism associated with OSA was observed in 73.5% of all SB. The risk factor for SB was endorsement ofnocturnal tooth grinding (odds ratio (OR) 5.69, 95%CI 1.74-18.58). Risk factors for severe bruxism were male sex (OR 4.01, 95%CI 1.02-15.88) and endorsementofnocturnal tooth grinding (OR 9.63, 95%CI 2.54-36.42). Risk factors for SB associated with OSA were non-supine RDI (OR 1.02, 95%CI 1.001-1.034) and endorsement ofnocturnal tooth grinding (OR 5.4, 95%CI 1.22-23.93). In SB group, when comparison was made between baseline portion and during optimal PAP, significant reduction of SBI was observed (5.5 (3.2, 9.3) vs. 0 (0, 2.1), p < 0.001). Median difference of SBI between baseline portion and during optimal PAP was 4.4 (2.0, 8.3) (p < 0.001). In this group of patients with OSA, almost half was observed to have SB in which the majority were associated with OSA. Optimal PAP resulted in a significant reduction in SB episodes. In addition to endorsement of nocturnal tooth grinding, non-supine RDI was observed to be a potential risk factor for SB associated with OSA.

Undiagnosed obstructive sleep apnea syndrome as a treatable cause of new-onset sleepiness in some post-COVID patients.

Infection with COVID-19 can lead to persistent sequelae, such as fatigue, daytime sleepiness or disturbed sleep, that can remain for more than 12 weeks and that are summarized as post-COVID syndrome. The causes remain unclear. The present study investigated the presence of sleep disorders in patients with post-COVID syndrome using polysomnography. Thirty-four patients with post-COVID syndrome and new-onset fatigue and sleepiness after a SARS-CoV2 infection underwent polysomnography in accordance with American Association of Sleep Medicine (AASM) standards as part of their clinical workup. Analysis was performed visually based on AASM criteria (scoring manual version 2.6, 2020). Polysomnography revealed a sleep efficiency of <80% in 50% of patients and a mean respiratory disturbance index (RDI) of 9.9 ± 15.4/h. Excluding central apneas, 12 patients (35%) had an RDI of ≥5/h, pointing to obstructive sleep apnea syndrome (OSAS; AASM 2014). Patients with a high RDI were significantly older (p = 0.01) and showed a trend towards a higher body mass index (p = 0.08) than patients with a normal RDI but had no other risk factors for OSAS. Six patients agreed to long-term treatment of their OSAS and all reported discontinuation of daytime symptoms. Post-COVID symptoms such as daytime sleepiness, fatigue and memory and concentration problems may in part be a result of reduced sleep efficiency and sleep apnea in a relevant percentage of patients. This possibly treatable cause of the symptoms should be kept in mind in patients presenting with post-COVID syndrome.

Fluoroscopic-Assisted Tongue Suspension: Advancement and Innovation in the Management of Complex Pediatric Obstructive Sleep Apnea.

The primary aim of this study is to describe a novel surgical technique developed for tongue base suspension (TBS). The second aim of this study is to assess the efficacy of the developed procedure by quantifying preoperative and postoperative polysomnographic outcomes for pediatric patients undergoing fluoroscopic-assisted tongue suspension (FATS) with the Encore System. Our hypothesis is that our FATS technique will provide at least a 50% reduction in the Apnea/Hypopnea Index (AHI), including in the medically complex pediatric population. Retrospective case series. An electronic medical record review was conducted of patients who underwent FATS by a single surgeon at a tertiary care medical center between December 2019 and June 2022. Inclusion criteria included all patients <18 years old with evidence of OSA or sleep-disordered breathing and who had glossoptosis on sleep endoscopy. Data extracted from the medical record included age, gender, medical comorbidity history, reason for referral, history of airway surgeries, length of hospital stay, surgical complications data, and preoperative and postoperative polysomnographic data. Surgical success was defined by at least a 50% reduction in AHI. Thirty patients (53.3% male) with a mean age of 6.3 (±5.3, 0.16-17) years underwent FATS over the study period. Most patients (93%) had an underlying comorbidity: cerebral palsy (37%), chromosomal abnormalities (23%), Down syndrome (13%), Pierre-Robin sequence (10%), and obesity (10%). The majority of patients (77%) were explicitly referred for tracheostomy placement secondary to failed management of OSA. 21 patients completed both preoperative and postoperative polysomnograms. The mean preoperative AHI, obstructive AHI (oAHI), and respiratory disturbance index (RDI) were 28.8 (±19.8), 30.8 (±19.6), and 30.5 (±19.3), respectively. The mean postoperative AHI, oAHI, and RDI were 7.3 (±9.2), 7.5 (±9.1), and 7.9 (±9.3), respectively. The mean change in AHI was -21.5 (±21.4) events/h (p < 0.01, 95% CI -29.0 to -11.4 events/h). The mean percentage decrease in AHI was 74.7%. The mean change in oAHI and RDI were -23.3 (±21.9) events/h (p < 0.01 95% CI- 39.9 to -21.4 events/h) and -22.5 (±21.5) events/h (p < 0.01, 95% CI- 31.5 to -12.4 events/h), respectively. The mean percentage decrease in oAHI and RDI was 75.6% and 73.8%, respectively. Surgical success occurred in 16 of the 21 (76%) patients. Of the 23 patients referred explicitly for tracheostomy placement, 21 (91%) were able to avoid tracheostomy placement secondary to improvements in OSA. Patients undergoing fluoroscopic-assisted TBS revealed statistically significant improvements in AHI, oAHI, and RDI, with an overall surgical success rate of 76%. Complication rates were minimal, despite the complex nature of the study population. FATS should be considered a viable surgical approach in pediatric patients with an identified base of tongue obstruction and OSA. 4 Laryngoscope, 134:S1-S9, 2024.

Sleep-disordered breathing in the acute phase of ischemic stroke

Objective. Sleep-disordered breathing (SDB) is a common cardiovascular risk factor. The aim of our study was to assess the occurrence and features of SDB in patients with acute supratentorial ischemic stroke. Design and methods. Patients 18-89 years of age with acute ischemic stroke admitted to the stroke intensive care unit within 24 hours after the symptom onset underwent respiratory monitoring during the first day of hospitalization. 1616 patients were screened between 2018 and 2021 years, respiratory monitoring was performed in 583 patients, and data from 281 patients [mean age 67 (30; 89) years, 146 males (52 %)] were included in the final analysis. Results. The mean respiratory disturbance index was 11,8 (0; 88)/h. SDB was detected in 182 patients (69,2 %), with mild severity in 28,6 %, moderate in 24,2 %, and severe in 47,2 %. Prevalent obstructive apnea type was observed in 71,1 %, central type in 14,2 %, and mixed type in 14,7 %. The TOAST stroke subtype distribution was the following: unspecified etiology was diagnosed in 52 %, cardioembolic in 26 %, atherothrombotic in 11 %, lacunar in 9 %, and other established etiology in 2 %. The majority of patients had mild stroke severity (89,4 %), moderate and severe stroke was diagnosed in 10,5 %. No significant differences in the main indices of the type and severity of sleep apnea were found in the groups based on severity and pathogenetic type of stroke. Conclusions. Our results correlate with the worldwide prevalence of SDB in patients with ischemic stroke (69,2 % and 71,1 %). Further analysis with inclusion of more patients with moderate and severe stroke is required, as well as a prospective study to assess the prognostic impact of SDB.

Advanced Proteomics and Cluster Analysis for Identifying Novel Obstructive Sleep Apnea Subtypes before and after Continuous Positive Airway Pressure Therapy.

Rationale: Studies have shown elevated inflammatory biomarkers in obstructive sleep apnea (OSA), but data after continuous positive airway pressure (CPAP) treatment are inconsistent. Objectives: We used the Olink proteomics panel to identify unique OSA clusters on the basis of inflammatory protein expression and assess the impact of CPAP therapy. Methods: Adults with newly diagnosed OSA had blood drawn at baseline and three to four months after CPAP. Samples were analyzed using the Olink proteomics platform, which measures 92 prespecified inflammatory proteins using proximity extension assay. Linear mixed-effects models were used to model changes in protein expression during the period of CPAP use, adjusting for batch, age, and sex. Unsupervised hierarchical clustering was performed to identify unique inflammatory OSA clusters on the basis of inflammatory biomarkers. Within-cluster impact of CPAP on inflammatory protein expression was assessed. Results: Among 46 patients, the mean age was 46 ± 12 years (22% women), mean body mass index was 31 ± 5 kg/m2, and mean respiratory disturbance index was 33 ± 17 events/hour. Unsupervised cluster and heatmap analysis revealed three unique proteomic clusters, with low (n = 21), intermediate (n = 19), and high (n = 6) inflammatory protein expression. After CPAP, there were significant within-cluster differences in protein expression. The low inflammatory cluster had a significant increase in protein expression (16%; P = 0.02), and the high inflammatory cluster had a significant decrease in protein expression (-20%; P = 0.003), more significant among those compliant with CPAP in the low (25%; P = 0.04) and high (-22%; P = 0.01) clusters. Conclusions: We identified three unique inflammatory clusters in patients with OSA using plasma proteomics, with a differential response to CPAP by cluster. Our results are hypothesis generating and require further investigation in larger longitudinal studies for enhanced cardiovascular risk profiling in OSA.

Comparative evaluation of the efficacy of customized maxillary oral appliance with mandibular advancement appliance as a treatment modality for moderate obstructive sleep apnea patients—a randomized controlled trial

BackgroundObstructive sleep apnea (OSA) is quite common among the adult population, according to recent epidemiological studies. The most frequently suggested alternate treatment for mild to moderate OSA is oral appliances (OA). The purpose of the present study was to assess as well as compare the effectiveness of custom-made maxillary oral appliances against mandibular advancement appliances in the care of individuals suffering from moderate obstructive sleep apnea.MethodsA prospective interventional research was carried out with 40 participants. Polysomnography (PSG) was done and the participants with an apnea-hypopnea index (AHI) >15–30 were involved in the research. Study participants were randomly split up into two test groups: group I was the “Control Group” (group treated with a mandibular advancement device (MAD), n=20), while group II was exposed to a “customized maxillary oral appliance” (CMOA, n=20). Both groups had reference measures for AHI, blood oxygen saturation (SpO2), oro-nasal airflow via respiratory disturbance index (RDI), and the Epworth Sleepiness Scale (ESS). Appliances were fabricated and delivered to the respective study group participants. PSG was again conducted after a period of 1 and 3 months of appliance delivery and re-evaluation was done for all the parameters and was compared with reference measurements. The facts were analyzed using descriptive and analytical statistical methods. The statistical program utilized in the study was “SPSS (Statistical Package for Social Sciences) Version 20.1.” After 1 and 3 months, the statistical significance between the two study groups was assessed at P<0.05.ResultsThe analysis of mean AHI, SPO2, RDI, and ESS for both test groups manifested statistically significant measures (P<0.001). The study results revealed a statistically significant depletion in mean AHI scores, improvement in mean SPO2 scores, and reduction in mean RDI scores and ESS scores when compared with reference measurements to 1 month, 1 to 3 months, and between reference measurements and 3 months.ConclusionThe CMOA was effective in managing moderate OSA and has great therapeutic potential. It can be an option for the MAD for treating patients suffering from moderate obstructive sleep apnea.Trial registrationThe study was registered under Clinical Trials Registry-India and the registration number is CTRI/2020/07/026936. Registered on 31 July 2020

Pharyngeal Inflammation on Positron Emission Tomography/Magnetic Resonance Imaging Before and After Obstructive Sleep Apnea Treatment.

Rationale: There is upper airway inflammation in patients with obstructive sleep apnea (OSA), which reduces with continuous positive airway pressure (CPAP) therapy. Objectives: Validate the use of positron emission tomography (PET)/magnetic resonance imaging (MRI) to quantify metabolic activity within the pharyngeal mucosa of patients with OSA against nasal lavage proteomics and assess the impact of CPAP therapy. Methods: Adults with OSA underwent [18F]-Fluoro-2-deoxy-D-glucose PET/MRI of the neck before and 3 months after initiating CPAP. Nasal lavage samples were collected. Inflammatory protein expression from samples was analyzed using the Olink platform. Upper airway imaging segmentation was performed. Target-to-background ratio (TBRmax) was calculated from target pharyngeal maximum standard uptake values (SUV) and personalized background mean SUV. Most-diseased segment TBRmax was identified per participant at locations with the highest PET avidity. Correlation analysis was performed between baseline TBRmax and nasal lavage proteomics. TBRmax was compared before and after CPAP using linear mixed-effect models. Results: Among 38 participants, the baseline mean age was 46.3 years (standard deviation [SD], 12.5), 21% were female, the mean body mass index was 30.9 kg/m2 (SD, 4.6), and the mean respiratory disturbance index measured by peripheral arterial tonometry was 31 events/h (SD, 16.4). There was a significant positive correlation between pharyngeal mucosa most-diseased segment TBRmax and nasal lavage proteomic inflammation (r = 0.41 [P < 0.001, false discovery rate = 0.002]). Primary analysis revealed a reduction in the most-diseased segment TBRmax after a median of 2.91 months of CPAP therapy (-0.86 [standard error (SE) ± 0.30; P = 0.007]). Stratified analysis by smoking status revealed a significantly decreased most-diseased segment TBRmax after CPAP therapy among never-smokers but not among ever-smokers (-1.01 [SE ± 0.39; P = 0.015] vs. -0.64 [SE ± 0.49; P = 0.201]). Conclusions: CPAP therapy reduces metabolic activity measured by PET/MRI within the upper airway of adults with OSA. Furthermore, PET/MRI measures of upper airway metabolic activity correlate with a noninvasive marker of inflammation (i.e., nasal lavage inflammatory protein expression).

Study of Nocturnal Oxygen Desaturation in Chronic Obstructive Pulmonary Disease Patients

Background: Abnormal sleep architecture with decreased rapid eye movement sleep and arousals during the periods of nocturnal oxygen desaturation (NOD) are seen in patients with chronic obstructive pulmonary disease (COPD) with significant consequences. This study was done to evaluate the prevalence of NOD and other sleep-related disorders in COPD patients. Patients and Methods: This prospective cross-sectional study was conducted in the sleep laboratory of our tertiary center over 1 year. Fifty COPD patients were enrolled in this study. They were classified into mild COPD and moderate COPD, according to the Global Initiative for Obstructive Lung Disease (GOLD) classification. Complete history, physical examination, and relevant laboratory investigations were taken. All patients were subjected to overnight polysomnography. Results: Eight patients had mild COPD, whereas 42 patients had moderate COPD. Mean sleep efficiency was decreased with an average of 71.08% with a significant difference between mild and moderate COPD cases. Minimal SpO2, average SpO2, SpO2

Cluster Analysis of Home Polygraphic Recordings in Symptomatic Habitually-Snoring Children: A Precision Medicine Perspective.

(1) Background: Sleep-disordered breathing (SDB) is a frequent problem in children. Cluster analyses offer the possibility of identifying homogeneous groups within a large clinical database. The application of cluster analysis to anthropometric and polysomnographic measures in snoring children would enable the detection of distinctive clinically-relevant phenotypes; (2) Methods: We retrospectively collected the results of nocturnal home-based cardiorespiratory polygraphic recordings and anthropometric measurements in 326 habitually-snoring otherwise healthy children. K-medoids clustering was applied to standardized respiratory and anthropometric measures, followed by Silhouette-based statistics. Respiratory Disturbance Index (RDI) and oxygen desaturation index (≤3%) were included in determining the optimal number of clusters; (3) Results: Mean age of subjects was 8.1 ± 4.1 years, and 57% were males. Cluster analyses uncovered an optimal number of three clusters. Cluster 1 comprised 59.5% of the cohort (mean age 8.69 ± 4.14 years) with a mean RDI of 3.71 ± 3.23 events/hour of estimated sleep (e/ehSleep). Cluster 2 included 28.5% of the children (mean age 6.92 ± 3.43 years) with an RDI of 6.38 ± 3.92 e/ehSleep. Cluster 3 included 12% of the cohort (mean age 7.58 ± 4.73 years) with a mean RDI of 25.5 ± 19.4 e/ehSleep. Weight z-score was significantly lower in cluster 3 [−0.14 ± 1.65] than in cluster 2 [0.86 ± 1.78; p = 0.015] and cluster 1 [1.04 ± 1.78; p = 0.002]. Similar findings emerged for BMI z scores. However, the height z-score was not significantly different among the 3 clusters; (4) Conclusions: Cluster analysis of children who are symptomatic habitual snorers and are referred for clinical polygraphic evaluation identified three major clusters that differed in age, RDI, and anthropometric measures. An increased number of children in the cluster with the highest RDI had reduced body weight. We propose that the implementation of these approaches to a multicenter-derived database of home-based polygraphic recordings may enable the delineation of objective unbiased severity categories of pediatric SDB. Our findings could be useful for clinical implementation, formulation of therapeutic decision guidelines, clinical management, prevision of complications, and long-term follow-up.

Influence of obesity and overweight on the association between sleep-disordered breathing and atrial fibrillation: the DASAP-HF study

Abstract Background The association between sleep apnea (SA) and atrial fibrillation (AF) has been well described. However, it remains unclear whether the association is causative or primarily dependent on shared comorbidities such as obesity. The Respiratory Disturbance Index (RDI) computed by an implantable cardioverter defibrillator (ICD) algorithm accurately identifies severe SA, whether central or obstructive in origin. Purpose In the present analysis we studied in patients with heart failure the contribution of obesity in the relationship between SA, measured by RDI, and AF. Methods Patients with ejection fraction ≤35% implanted with an ICD endowed with an algorithm (ApneaScan) that calculates the RDI each night, were enrolled and followed-up for 24 months. The weekly mean RDI value was considered, as calculated during the entire follow-up period. The endpoint was daily AF burden of ≥6 hours. Results 164 patients (age 67±10 years, 75% male, ejection fraction 29±5%) had usable RDI values during the entire follow-up period. Body mass index (BMI) was &amp;lt;25 kg/m2 in 62 patients (normal), 25.0–29.9 kg/m2 in 66 patients (overweight), ≥ 30 kg/m2 in 36 patients (obese). When compared with normal patients (31±11 episodes/h), the average RDI value calculated during the entire follow-up period did not differ in overweight patients (35±13 episodes/h, p=0.114), but was significantly higher in obese patients (39±12 episodes/h, p=0.002). During follow-up, AF burden ≥6 hours/day was documented in 48 (29%) patients (BMI ≥ versus &amp;lt;25 kg/m2; HR: 1.47, 95% CI: 0.83–2.60, p=0.197; BMI ≥ versus &amp;lt;30 kg/m2; HR: 0.98, 95% CI: 0.46–2.09, p=0.963). Based on the ROC curve analysis, average RDI ≥37 episodes/h maximized sensitivity and specificity for the prediction of AF (Area under the curve: 0.63, 95% CI: 0.55–0.70, p=0.011). Device-detected RDI ≥37 episodes/h was associated with the occurrence of AF on univariate analysis (HR: 3.88, 95% CI: 2.02–7.44, p&amp;lt;0.001), as well as after correction for either BMI ≥25 kg/m2 (HR: 3.76, 95% CI: 1.94–7.26, p&amp;lt;0.001), or BMI ≥30 kg/m2 (HR: 4.15, 95% CI: 2.15–8.04, p&amp;lt;0.001). Conclusions In heart failure patients, we confirmed the association between ICD-detected SA and AF, an association that persisted independent of patient body habitus. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The study is supported by a research grant from Boston Scientific

Device-detected sleep-disordered breathing predicts implantable defibrillator therapy in patients with heart failure

Abstract Funding Acknowledgements Type of funding sources: None. Background Sleep-disordered breathing is highly prevalent in heart failure (HF) and it has been suggested as a risk factor for malignant ventricular arrhythmias. The Respiratory Disturbance Index (RDI) algorithm computed by select implantable cardioverter defibrillators (ICDs) can identify severe sleep apnea (SA). Purpose In the present analysis we evaluated the association between ICD-detected SA and the incidence of appropriate ICD therapy in patients with HF. Methods We enrolled 411 HF patients (age 69±10years, 77% male, ejection fraction 32±8%), implanted with an ICD endowed with an algorithm (ApneaScan, Boston Scientific) that calculates the RDI each night. In this analysis the weekly mean RDI value was considered. The endpoint was the first appropriate ICD shock. The median follow-up was 26 months [25th–75th percentile: 16-35]. Results During follow-up, one or more ICD shocks were documented in 58 (14%) patients. Patients with shocks were younger (66±13years versus 70±10years, p=0.038), and more frequently implanted for secondary prevention (21% versus 10%, p=0.026). The maximum RDI value calculated during the entire follow-up period did not differ between patients with and without shocks (55±15episodes/h versus 54±14episodes/h, p=0.539). However, the ICD-detected RDI showed a considerable variability during follow-up. The overall median of the weekly RDI was 33episodes/h [25th–75th percentile: 24-45]. Using a time-dependent Cox regression model, the continuously measured weekly mean RDI≥45episodes/h was independently associated with shock occurrence (HR:4.63, 95%CI:2.54-8.43, p&amp;lt;0.001), after correction for baseline confounders (age, secondary prevention). Conclusions In HF patients, patients were more likely to receive appropriate ICD shocks during periods of time when they exhibited more sleep-disordered breathing.

Association between implantable defibrillator-detected sleep apnea and atrial fibrillation: The DASAP-HF study.

The Respiratory Disturbance Index (RDI) computed by an implantable cardioverter defibrillator (ICD) algorithm accurately identifies severe sleep apnea (SA). In the present analysis, we tested the hypothesis that RDI could also predict atrial fibrillation (AF) burden. Patients with ejection fraction ≤35% implanted with an ICD were enrolled and followed up for 24 months. One month after implantation, patients underwent a polysomnographic study. The weekly mean RDI value was considered, as calculated during the entire follow-up period and over a 1-week period preceding the sleep study. The endpoints were as follows: daily AF burden of ≥5 min, ≥6 h, ≥23 h. Here, 164 patients had usable RDI values during the entire follow-up period. Severe SA (RDI ≥ 30 episodes/h) was diagnosed in 92 (56%) patients at the time of the sleep study. During follow-up, AF burden ≥ 5 min/day was documented in 70 (43%), ≥6 h/day in 48 (29%), and ≥23 h/day in 33 (20%) patients. Device-detected RDI ≥ 30 episodes/h at the time of the polygraphy, as well as the polygraphy-measured apnea hypopnea index ≥ 30 episodes/h, were not associated with the occurrence of the endpoints, using a Cox regression model. However, using a time-dependent model, continuously measured weekly mean RDI ≥ 30 episodes/h was independently associated with AF burden ≥ 5 min/day (hazard ratio [HR]: 2.13, 95% confidence interval [CI]: 1.24-3.65, p = .006), ≥6 h/day (HR: 2.75, 95% CI: 1.37-5.49, p = .004), and ≥23 h/day (HR: 2.26, 95% CI: 1.05-4.86, p = .037). In heart failure patients, ICD-diagnosed severe SA on follow-up data review identifies patients who are from two- to three-fold more likely to experience an AF episode, according to various thresholds of daily AF burden.

CI-524-02 ASSOCIATION BETWEEN DEVICE-DETECTED SLEEP APNEA AND IMPLANTABLE DEFIBRILLATOR THERAPY IN PATIENTS WITH HEART FAILURE

Sleep-disordered breathing is highly prevalent in heart failure (HF) and it has been suggested as a risk factor for malignant ventricular arrhythmias. The Respiratory Disturbance Index (RDI) algorithm computed by select implantable cardioverter defibrillators (ICDs) can identify severe sleep apnea (SA). In the present analysis we evaluated the association between ICD-detected SA and the incidence of appropriate ICD therapy in patients with HF. We enrolled 411 HF patients (age 69±10years, 77% male, ejection fraction 32±8%), implanted with an ICD endowed with an algorithm (ApneaScan, Boston Scientific) that calculates the RDI each night. In this analysis the weekly mean RDI value was considered. The endpoint was the first appropriate ICD shock. The median follow-up was 26 months [25th-75th percentile: 16-35]. During follow-up, one or more ICD shocks were documented in 58 (14%) patients. Patients with shocks were younger (66±13years versus 70±10years, p=0.038), and more frequently implanted for secondary prevention (21% versus 10%, p=0.026). The maximum RDI value calculated during the entire follow-up period did not differ between patients with and without shocks (55±15episodes/h versus 54±14episodes/h, p=0.539). However, the ICD-detected RDI showed a considerable variability during follow-up. The overall median of the weekly RDI was 33episodes/h [25th-75th percentile: 24-45]. Using a time-dependent Cox regression model, the continuously measured weekly mean RDI≥45episodes/h was independently associated with shock occurrence (HR:4.63, 95%CI:2.54-8.43, p<0.001), after correction for baseline confounders (age, secondary prevention). In HF patients, patients were more likely to receive appropriate ICD shocks during periods of time when they exhibited more sleep-disordered breathing.

The variability and burden of severe sleep apnea and the relationship with atrial fibrillation occurrence: analysis of pacemaker-detected sleep apnea

Study objectivesThis was a pilot study to evaluate the long-term variability and burden of respiratory disturbance index (RDI) detected by pacemaker and to investigate the relationship between RDI and atrial fibrillation (AF) event in patients with pacemakers.MethodsThis was a prospective study enrolling patients implanted with a pacemaker that could calculate the night-to-night RDI. The mean follow-up was 348 ± 34 days. The RDI variability was defined as the standard deviation of RDI (RDI-SD). RDI burden was referred to as the percentage of nights with RDI ≥ 26. The patient with RDI ≥ 26 in more than 75% nights was considered to have a high sleep apnea (SA) burden. An AF event was defined as a daily AF duration > 6 h.ResultsAmong 30 patients, the mean RDI of the whole follow-up period was 24.5 ± 8.6. Nine (30%) patients were diagnosed with high SA burden. Patients with high SA burden had a higher BMI (26.7 ± 4.8 vs 23.2 ± 3.9, p = 0.036), a higher prevalence of hypertension (86% vs 39%, p = 0.031), and a larger left ventricular diastolic diameter (49.2 mm vs 46.7 mm, p = 0.036). The RDI-SD in patients with a higher burden was significantly greater than that in the patients with less burden (10.7 ± 4.9 vs 5.7 ± 1.4, p = 0.036). Linear regression showed that participants with a higher RDI tended to have a higher SD (R = 0.661; p < 0.001). The mean RDI (OR = 1.118, 95%CI 1.008–1.244, p = 0.044) was associated with AF occurrence.ConclusionUsing a metric such as burden of severe SA may be more appropriate to demonstrate a patient’s true disease burden.

Serum high-mobility group box 1 protein level correlates with the lowest SaO2 in patients with sleep apnea: a preliminary study

IntroductionSerum level of high-mobility group box 1 protein is reportedly correlated with the severity of obstructive sleep apnea. ObjectiveWe tried to evaluate the possibility of using the serum high-mobility group box 1 protein level as a biologic marker in obstructive sleep apnea patients. MethodsWe generated a chronic intermittent hypoxia murine model that reflected human obstructive sleep apnea. Obstructive sleep apnea patients who underwent polysomnography were prospectively enrolled. Serum samples were obtained from mice and obstructive sleep apnea patients, and the serum high-mobility group box1 protein level was measured by enzyme-linked immunosorbent assay. ResultsSerum high-mobility group box 1 protein level was 56.16 ± 30.33 ng/mL in chronic intermittent hypoxia and 18.63 ± 6.20 ng/mL in control mice (p < 0.05). The mean apnea-hypopnea index and respiratory disturbance index values of enrolled obstructive sleep apnea patients were 50.35 ± 27.96 and 51.56 ± 28.53, respectively, and the mean serum high-mobility group box 1 protein level was 30.13 ± 19.97 ng/mL. The apnea–hypopnea index and respiratory disturbance index were not significantly correlated with the serum high-mobility group box 1 protein level (p > 0.05). Instead, this protein level was significantly correlated with lowest arterial oxygen concentration (SaO2) (p < 0.05). ConclusionHigh-mobility group box 1 protein may be involved in the pathogenesis of obstructive sleep apnea, and the possibility of this protein being a useful biologic marker in obstructive sleep apnea should be further evaluated.

Study of obstructive sleep apnea parameters in patients of nasal polyposis using peripheral arterial tonometry

Background: Obstructive sleep apnea (OSA) syndrome is characterized by partial or complete cessation of airflow and oxygen desaturation during sleep owing to upper airway collapse. This study assesses the OSA parameters in nasal polyposis patients before and after functional endoscopic sinus surgery (FESS) with the help of peripheral arterial tonometry (PAT) device. Methodology: This was a prospective study done in the months of April 2015 to June 2016. Patients with bilateral nasal polyps with Lund Mackay Scoring marking equal to and more than two of both sides. Thirty patients willing to undergo PAT sleep study before and after FESS were recruited. The sleep parameters thus obtained in the pre- and postoperative period were analyzed. Results: Out of 30 patients, 22 patients were male and eight patients were female. The mean age was 43.17 with standard deviation of 10.06 years. The mean body mass index was 29.12 with a standard deviation of 5.76. All patients underwent FESS. The PAT study was done before and after surgery. Snoring grading and Epworth Sleepiness Scale scoring improved in the majority of patients after surgery. The mean respiratory disturbance index (RDI) in the preoperative period was 32.7 which decreased to 11.34 in the postoperative period. The mean apnea hypopnea index (AHI) in the preoperative period was 22.85 which decreased to 6.34 in the postoperative period. The mean oxygen desaturation index (ODI) in the preoperative period was 16.8 which decreased to 4.4 after surgery. Significant correlation (P < 0.001) was found between pre- and postoperative RDI, AHI, ODI, and oxygen desaturation events. Conclusion: The OSA parameters before and after endoscopic sinus surgery in nasal polyposis patients got improved. The PAT device, which is the newest novel plethysmograph, proved to be a reliable device for the assessment of sleep apnea parameters in nasal polyposis in the pre- or postoperative period.

Severe sleep apnea is associated with atrial fibrillation burden in pacemaker recipients

Abstract Background New generation pacemaker allow the assessment day by day of sleep disordered breathing (SDB) based on impedance measurement. A recent study demonstrated that incidence of AF is higher in case of severe SA monitored by pacemaker Purpose The aim was to compare the atrial fibrillation (AF) burden between patients with severe and non-severe sleep apnea (SA) detected with pacemakers monitoring (SDB). Methods This retrospective study was carried out at our University Hospital. We included all patients with Microport CRM pacemaker implanted from 2013 to 2016 at our university hospital. Exclusion criteria were inactivation of sleep apnea monitoring (SAM), history of sleep apnea, missing data or invalid data. AF burden was assessed according to Fallback mode switch (FMS) duration. Respiratory disturbance index (RDI) was calculated as the average number of events (ventilation pause and reductions) per number of hours of monitoring. Patients with RDI&amp;lt;20/h were compared with patients with RDI≥20/h (considered as severe SA group). Results 404 patients (mean age = 79.7±10 years; 52.0% men) were included. The most prevalent indication for cardiac pacing was atrioventricular block in 57%. Mean RDI was 18.9 events per hour. 234 (58%) of them had a mean RDI &amp;lt;20 and 170 (42%) had a mean RDI ≥20. Compared to patients with mean RDI&amp;lt;20, those with mean RDI ≥20 were youngers (78.6±10 years Vs 81.8±8 years; p=0.02), were more likely to be male (58.2% Vs 47.5%: p=0.035) and had more heart failure history (28.8% Vs 19.2%: p=0.03). BMI was not different between groups (26.3±5. vs 26.3±4; P=0.33). Mean follow-up was 27 months. Patients with RDI ≥20 had a mean Atrial fibrillation duration longer than patients with RDI &amp;lt;20 (631 min Vs 291 min respectively; p=0.014). RDI was correlated with FMS (r=0.26; p=0.0004). The stroke rate tended to be higher in the RDI ≥20 group (2.1% vs 5.4%) (p=0.12). Conclusion Severe SA detected by pacemaker was associated with longer AF duration. We did not find higher occurrence of stroke in the severe SA group. Funding Acknowledgement Type of funding source: None

ICD-detected respiratory disturbance index: accuracy for sleep apnea detection and prognostic value

Abstract Purpose In patients affected by heart failure an association exists between sleep apnea (SA) measured by polysomnography and adverse outcome. Impedance-based implantable cardioverter defibrillator (ICD) algorithms have been designed to compute the Respiratory Disturbance Index (RDI) to identify severe SA. The purpose of the DASAP-HF study was to evaluate the accuracy of RDI for the prediction of severe SA, and investigate the prognostic value of device-detected RDI values. Methods Patients with left ventricular ejection fraction ≤35% implanted with an ICD were enrolled and followed for 24 months. One month after implantation, patients underwent a polysomnographic study (PS) for assessing the apnea-hypopnea index (AHI). The average RDI value was calculated over a 1-week period preceding the sleep study and compared with the assessment of severe SA at PS (AHI ≥30 episodes/h). The endpoint was all-cause death after 24 months. Results 224 out of 265 enrolled patients had usable RDI values. Patients characteristics: 79% male, 67±10 years, BMI 27±7kg/m2, ejection fraction 29±5%, 54% ischemic cardiomyopathy, 50% CRT-D. The mean AHI value at PS was 21±15 episodes/h. The mean RDI value recorded during the week preceding PS was 30±16 episodes/h. RDI values accurately identified severe SA diagnosed at PS (AUC 0.77; 95% CI 0.70–0.83; P=0.001). Based on the ROC curve analysis, RDI ≥29 episodes/h and AHI ≥17 episodes/h maximized sensitivity and specificity for the prediction of death. Both indexes were independently associated with all-cause death but, after correction for the other independent significant prognostic variables, RDI≥29episodes/h yielded stronger prediction (HR: 12.22, 95% CI:1.64–91.37, p=0.015) as compared to AHI ≥17episodes/h (HR: 4.14, 95% CI:1.17–14.66, p=0.028). Moreover, severe SA diagnosed at PS (AHI ≥30episodes/h) was not associated with death (HR: 1.20, 95% CI:0.3817–3.8266, p=0.761). Conclusions In heart failure patients indicated to ICD, severe SA was confirmed to be associated with survival. The ICD-measured RDI accurately identified severe SA detected at PS, and was associated with the risk of death at long-term. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Boston Scientific

The coexistence of obstructive sleep apnea in patients with slow coronary flow: a cross-sectional study

BACKGROUND: Interestingly, obstructive sleep apnea (OSA) and coronary slow-flow (CSF) have similar pathogenic mechanisms, including increased sympathetic activity and endothelial dysfunction. However, the association between OSA and CSF is not known well. If undiagnosed, OSA is a cause of increased cardiovascular morbidity and mortality. We investigated the presence of OSA in the patients diagnosed CSF after coronary angiography. METHODS: The prospective cross-sectional study included 4515 patients admitted angiography laboratory from February 2018 to March December 2019. After coronary angiography of 4515 patients, 336 patients were diagnosed as slow coronary flow. These patients were examined by pulmonology and sleep specialist. Of the 336 patients, 276 patients were found high risk in terms of OSA by using Berlin questionnaire (BQ). Only 75 of 276 patients underwent polysomnography (PSG) testing. Control group patients (n=40) had normal coronary artery and no OSA. RESULTS: Of 4515 patients, 336 (7.4%) met the criteria for CSF. After BQ, 276 of 336 patients had high-score BQ (82.1%). The study group consisted of 276 patients (188 males, 88 females). The mean ages of the study group were 48.48 ±7.61 years. Body mass index (BMI) according to WHO criteria was 33.02±2.18 kg/m2. When 75 patients underwent PSG were divided on two groups as mild OSA and moderate/severe OSA according to respiratory disturbance index (RDI). We found a significant positive correlation between mean corrected TIMI Frame Count (CTFC) and RDI. While CTFC-Lad in mild OSA group was 32.73, CTFC-Lad in moderate/severe OSA group was 35.04 (p=0.022). While CTFC-Cx in mild OSA group was 31.67, CTFC-Cx in moderate/severe OSA group was 35.26 (p=0.001). While CTFC-Rca in mild OSA group was 32.57, CTFC-Rca in moderate/severe OSA group was 36.33 (p<0.001). CONCLUSION: This study revealed the coexistence between CSF and OSA. Moreover, we demonstrated a significant relationship between mean CTFC and RDI. To determine the clinical association of OSA and CSF may be help to understand pathophysiology of CSF.

847Interim analysis of the device-detected cardiac tachyarrhythmic events and sleep-disordered breathing (DEDiCATES)" study; focused on baseline characteristics

Abstract Funding Acknowledgements This work is supported by Boston Scientific. Background/introduction: Sleep-disordered breathing (SDB) is one of the common comorbidities in cardiac implantable electronic devices (CIED) patients. It’s feasible to detect SDB using specialized diagnostic function of CIEDs showing comparable performance in diagnostic accuracy of SDB to conventional polysomnography. To date, few studies have investigated the prognostic value of CIED-detected SDB in cardiovascular risk. Purpose In the Device-Detected CArdiac Tachyarrhythmic events and Sleep-disordered breathing (DEDiCATES) study, we aim to determine whether device-detected sleep-disordered breathing (SDB) events are associated with increased risk of cardiac arrhythmias or other cardiovascular (CV) outcomes. Here, we present interim baseline data of the study population to investigate the baseline prevalence and severity of device-detected SDB in CIED patients. Methods The study was designed as a prospective, multicenter, and observational study to include 600 patients. Eligible patients have dual chamber CIEDs with SDB detection function which reports the average number of sleep disturbance events per hour per night in the form of a Respiratory Disturbance Index (RDI). The daily RDI values were collected to measure the severity and burden of SDB. The baseline severity of SDB was determined according to RDI data recorded during the first 1 week, 1 month, and 3 ± 1 months after CIED implantation; patients with RDI≥ 30/h for at least one night are classified into the severe SDB group. Results A total of 313 patients who completed the first device interrogation at 3 ± 1 months were included for analysis. The mean age and CHA2DS2VASc score were 69 and 3.1, respectively. Forty-nine percent of patients were men, and 35.5% were classified as high risk for SDB by Berlin questionnaire. The rate of severe SDB increased with longer monitoring period (83.8% at 1week, 91.6% at 1 month, and 96.4% at 3 ± 1 months). There was no baseline demographic difference between the severe and non-severe SDB groups, except that baseline body mass index (BMI) was higher in the severe group (24.5% vs. 21.5%, p = 0.01). The mean RDI was 36.3, 34.2, and 33.0 per night during the first 1 week, 1 month, and 3 ± 1 months, respectively. Considering the limitation of the categorical criteria of baseline severity, we arbitrarily reclassified the patients according to median mean RDI value. Men were more frequent and BMI was higher in the above-mean RDI group compared to the below-mean RDI group. Using logistic regression analysis, we identified that BMI and male gender were associated with patients with above-mean RDI. Conclusions Conventional categorical classification of SDB severity seems to be limited in its ability to discriminate high risk patients. Thus, more suitable RDI-related variables need to be identified in future outcome analysis. Abstract Figure. Prevalence of baseline severe SDB