Split-night Studies Research Articles

Sleep and follow-up characteristics of Hispanic patients: Insights from a comparative analysis with White patients in polysomnographic split-night studies

BackgroundLimited attention has been given to exploring the efficacy of titration in split-night polysomnography (PSG) and the factors influencing adherence to continuous positive airway pressure (CPAP) therapy. This study aims to evaluate the severity of OSA and PSG parameters in HP compared to WP. MethodsSplit-night PSG studies conducted on adults. Participants were categorized based on self-reported ethnicity as either HP or WP. ResultsThe study enrolled 50 WP (15 women, 35 men, mean age 60.5 ± 13.60 years, mean BMI 34.2 ± 7.48) and 45 HP (24 women, 21 men, mean age 54.9 ± 13.06 years, mean BMI 37.3 ± 7.88). HP exhibited a mean apnea-hypopnea index (AHI) of 51.1 ± 33.67, saturation nadir of 77.8 ± 10.19, and time spent with saturation <90% of 21.0 ± 26.93 min. In WP, the mean AHI was 39.2 ± 24.49, saturation nadir 81.6 ± 9.04, and time spent <90% was 10.4 ± 17.17 min. All observed differences were statistically significant (p < 0.05). Auto CPAP was prescribed to all patients, with adherence at 3–4 months being 75% ± 30 for HP, with a usage of 5.5 ± 2.2 h, and a residual AHI of 3 ± 3.5. In WP, adherence was 79% ± 30, usage was 5.9 ± 2.1 h, and residual AHI was 3.6 ± 6.2. None of these differences reached statistical significance. Among HP, 37% missed follow-up appointments compared to 12% of WP. More HP used full-face masks, while more WP preferred nasal masks. ConclusionsHP exhibited significantly worse OSA parameters during the diagnostic phase of PSG compared to WP. HP had a significantly higher no-show percentage than WP. CPAP adherence and residual AHI were not statistically different, but more HP missed follow-up appointments than WP.

Abstract 19050: Polysomnography and Sleep Symptom-Based Patient Profiles Associated With Atrial Fibrillation Development

Introduction: Although sleep disorders are linked to atrial fibrillation (AF), the complex interplay remains unclear. Investigating sleep-based profiles associated with AF can deepen understanding and identify at-risk patients. Hypothesis: We hypothesized discrete phenotypes of symptoms and polysomnography (PSG)-based data differ in relation to incident AF. Methods: This retrospective cohort study of Cleveland Clinic patients (age&gt;18) who underwent PSG 11/27/2004-12/30/2015 identified patient clusters using latent class analysis of 23 sleep-related symptoms, Epworth Sleepiness Scale (ESS) score, and 24 PSG measures of sleep disordered breathing and architecture. Cox proportional hazards models with cluster membership as the independent variable and incident AF as the dependent variable were adjusted for age, sex, race, BMI, cardiopulmonary disease and risk factors, anti-arrhythmic medication, and positive airway pressure with follow up 7.6±3.4 years. Results: Of the sample (n=43,433, age 52±15, 52% male, 74% White) 9% developed AF. Five clusters were identified: 1) Hypoxic + Sleepy (n=3,245): highest % time SaO 2 below 90%, highest ESS, 2) Apneas + Arousals (n=4,592): highest AHI, highest arousal index, 3) Short sleep + Low %REM (n=6,126): shortest sleep duration, longest REM latency, lowest %REM, 4) Hypopneas (n=2,661): most hypopneas, 5) Long sleep + High %REM (n=26,809): longest sleep duration, shortest REM latency, highest %REM (reference). Compared to reference, Hypoxic + Sleepy had 48% (HR=1.48, 95%CI=1.34-1.64), Apneas + Arousals had 22% (HR=1.22, 95%CI=1.11-1.35), and Short Sleep + Low %REM had 11% (HR=1.11, 95%CI=1.01-1.22) higher risk of AF development. Internal validation indicated reasonable predictive accuracy. Sensitivity analysis excluding split night studies confirmed the associations observed. Conclusions: Of 5 patient profiles identified, Hypoxic + Sleepy conferred the strongest AF risk. Consistent with prior evidence of hypoxia as an AF driver and cardiovascular risk of the sleepy phenotype, this constellation of symptoms and physiology illustrates risk in the clinical setting, providing potential value as a risk prediction tool. Future investigation will focus on external validation of these findings.

1003 Immediate Improvement of Second Degree Heart Block With Effective Treatment of Sleep-Disordered Breathing

Abstract Introduction Cardiac arrhythmia and heart block in particular is commonly found in association with obstructive sleep apnea (OSA). Here we describe real-time responsivity of 2nd degree heart block to treatment of OSA with positive airway pressure (PAP) during a titration study. Report of case(s) Our patient is a 70-year old man without significant cardiovascular disease. He presented with loud snoring and excessive daytime sleepiness. A home sleep apnea test in July 2020 revealed obstructive sleep apnea (respiratory event index 20, oxygen saturation nadir 86%). The patient was treated with auto-adjusting continuous positive airway pressure (APAP) and had symptomatic benefit. His most recent machine data download suggested an elevated residual respiratory event index (REI) of 19.6, 16.5 of which were central. A split-night study was performed to re-characterize the nature of the patient’s obstructive sleep apnea and treatment needs. The baseline portion of the study (AHI 50.8, oxygen saturation nadir 86%) was notable for the presence of frequent 2nd degree heart block (171.0 events/hour of recording). During the titration portion of the study, frequent central sleep apneas emerged with the addition of PAP therapy, consistent with treatment-emergent central sleep apnea. The patient was transitioned to bilevel positive airway pressure spontaneous timed mode (BPAP ST), and a pressure setting of 13/6 cm of water with backup rate of 14 breaths per minute effectively controlled his sleep-disordered breathing. The heart block that had been observed during the baseline portion of the study dramatically improved with the start of BPAP ST. Once the patient’s sleep-disordered breathing was controlled, the patient’s heart block occurred at a rate of only 12.1 events/hour of recording. Conclusion Treatment of sleep apnea has been established to be beneficial for the improvement of cardiac arrhythmias. This case is remarkably instructive in that attainment of an effective treatment setting for sleep-disordered breathing resulted in an almost immediate improvement of heart block. Support (if any)

0476 Peripheral Arterial Tonometry-Based Home Sleep Apnea Test vs. Polysomnography in Detection of Central Disordered Breathing Events

Abstract Introduction In-laboratory polysomnography (PSG) is the gold standard diagnostic test for sleep-disordered breathing (SDB). WatchPAT® is a type of home sleep apnea testing (HSAT) that utilizes peripheral arterial tone (PAT) signals and other sensors to evaluate for SDB. There is an abundance of data to support the use of a PAT-based HSAT for obstructive sleep apnea (OSA), though data to support its use in central sleep apnea (CSA) in the general population undergoing PSG is lacking. We therefore aimed to compare the agreement of a PAT-based HSAT and PSG in detecting central disordered breathing events in the general population undergoing PSG. Methods A prospective cross-sectional study was conducted in eligible adult participants with suspected sleep apnea who were scheduled to undergo diagnostic or split-night PSG at the Center for Sleep Medicine at Mayo Clinic in Rochester, MN, between May 2021 and October 2022. The PAT-based HSAT was applied during the night of PSG to obtain simultaneous recording. Subjects were excluded if they had chronic atrial fibrillation, permanent pacemaker, or finger deformity precluding finger probe use or if they were on alpha- antagonists or short-acting nitrates. The PAT-based HSAT data were automatically scored with the use of proprietary software, and the PSG data were manually scored by registered polysomnography technologists. All studies were reviewed by board-certified sleep medicine providers. Results A total of 147 subjects (53% female) were included in the final analysis after excluding 18 subjects due to malfunction of the PAT-based HSAT. The subjects had a mean age of 58±15 yrs and BMI of 34±9 kg/m². 95 (65%) subjects underwent split-night studies. OSA was diagnosed in 81% with a mean PSG AHI of 28±27 events per hour. CSA was diagnosed in 3% of subjects with a mean PSG AHI of 33±27 events per hour. Of the total 2120 central disordered breathing events reported by the PAT-based HSAT (mean pAHIc 3±5 events per hour), 365 (17%) correlated with central apneas and 78 (3.7%) correlated with central hypopneas found on PSG. Conclusion In our prospective study, the PAT-based HSAT demonstrated low positive predictive value in detecting central disordered breathing events when compared to PSG. Support (if any)

The burden of sleep disordered breathing in infants with Down syndrome referred to tertiary sleep center.

Children with Down Syndrome (DS) are at high risk of sleep disordered breathing (SDB). We aimed to examine the burden of SDB in infants with DS referred to tertiary sleep center. Infants (≤12 months old) with DS who underwent consecutive polysomnography (PSG) at a single academic sleep center over a 6-year period were included. obstructive sleep apnea(OSA) (obstructive apnea hypopnea index [oAHI]>1/hr), central sleep apnea (central apnea index > 5/h) and the presence of hypoventilation (% time spent with CO2 > 50 mmHg either by end-tidal or transcutaneous> 25% of total sleep time) and hypoxemia (time spent with O2 saturation <88% >5 min) were ascertained. A total of 40 infants were included (Mean age 6.6 months, male 66%). PSGs consisted of diagnostic (n = 13) and split night (n = 27, 68%) studies. All met criteria for OSA with mean oAHI 34.6/h(32.3). Central sleep apnea was present in 11 (27.5%) of infants. A total of 11 (27.5%) had hypoxemia. Hypoventilation was present in 10 (25%) infants. This study highlights the high prevalence of SDB in infants with DS referred to a sleep center, and supports early PSG assessment in this patient population.

0854 A case of complete heart block in a patient with severe obstructive sleep apnea

Abstract Introduction Obstructive sleep apnea (OSA) has been associated with bradycardic arrythmias and cases of transient heart block. Heart block occurring during sleep has been described in up to 10% of patients with obstructive sleep apnea, most commonly during stage R sleep and through a mechanism known as vagal activation. Stage R sleep is associated with desynchronization of respiratory and cardiovascular functions, and the excessive autonomic response (vagal activation) occurs due to the stronger stimulation of chemoreceptors and baroreceptors induced by hypoxemia, intrathoracic pressure swings, and hemodynamic alterations. Treatment of the underlying sleep-disordered breathing will typically treat the bradycardic arrythmia as well. Report of Cases: A 49-year-old male with a BMI of 30 kg/m , neck circumference of 16 inches, and obstructive sleep apnea presented to the sleep center to establish care for management of his preexisting OSA. He was previously diagnosed with moderate OSA in 2007 but had discontinued therapy shortly after due to Continuous Positive Airway Pressure (CPAP) intolerance. The patient complained of snoring, nocturia, and excessive daytime sleepiness (18/24 on Epworth Sleepiness Scale). During the split night study, the patient was noted to have 2:1 second degree heart block followed by a transient episode of complete heart block, manifested by 4 non-conducted p-waves. The patient remained asymptomatic throughout the night. Upon study completion, the patient denied any prior chest pain, presyncope, syncope, or medications that might cause heart block. Conclusion Bradyarrythmias can be seen in severe obstructive sleep apnea in the setting of excessive vagal stimulation through increased stimulation of chemoreceptors and baroreceptors. Treatment with PAP therapy can lead to prevention of heart block in 80-90% of these patients. Support (If Any)

WITHDRAWN

TOPIC: Sleep Disorders TYPE: Fellow Case Reports INTRODUCTION: Vagal nerve stimulation (VNS), which was approved by the FDA in 1997, has been used to treat refractory partial and complex seizures in patients with epilepsy. In this case report, we describe an important adverse effect of vagal nerve efferent stimulation to upper airway structures. Multiple studies have shown that VNS can induce or worsen obstructive sleep apnea (OSA). For treating patients with VNS-induced OSA, manufacturers suggest decreasing VNS frequency and increasing the cycle off time. However, this recommendation rarely provides successful results. Here, we illustrate a case of a woman with VNS-induced OSA and show how small adjustments to VNS current and pulse width parameters can significantly reduce the effects of VNS-induced obstructive respiratory events during a PAP titration without breakthrough seizures. CASE PRESENTATION: The patient is a 52-year-old woman who had a vagal nerve stimulator placed in 1998 for refractory left frontal lobe focal seizures. She presented to the sleep medicine clinic for excessive daytime sleepiness, non-refreshing sleep, and reports of loud snoring. Her symptoms were present despite adequate sleep hygiene and a consistent 8.5 hours of sleep each night. A split night study revealed an apnea-hypopnea index (AHI) of 32.8 with predominant obstructive hypopneas and occasional obstructive apneas. Her obstructive respiratory events occurred coincidentally in sequence with 30 seconds of electromyography (EMG) chin tone every 108 seconds. Subsequent, bilevel positive airway pressure (BPAP) titration was unsuccessful. The patient's neurologist was notified of the sleep study findings and the patient's VNS was adjusted. The output current, pulse width, magnet current, and a magnet pulse bandwidth were reduced. All other parameters remained unchanged including frequency and cycle time. On her subsequent BPAP titration, her OSA was successfully controlled at a BPAP pressure of 23/19 cm H2O, with a residual AHI of 0. On follow-up, the patient was adherent to her BPAP therapy with subjective improvement in quality of her sleep. The patient did not have breakthrough seizures over one year with the decrease in current and pulse width settings on her VNS. She averaged 5.5 hours of BPAP use each night with 73% of days used over one year. DISCUSSION: In this case report, we have outlined a successful BPAP titration with minor adjustments in VNS parameters in a patient with epilepsy and severe OSA. The success of this BPAP titration was likely facilitated by the reduction in VNS output current and pulse bandwidth, which reduced the efferent motor nerve stimulation of upper airway structures. CONCLUSIONS: This case demonstrates how adjustment of specific VNS parameters may potentially provide an alternative to the recommended adjustment in frequency and cycle times; however, this strategy will ultimately need to be tested and closely monitored in more patients. REFERENCE #1: Howland RH. Vagus Nerve Stimulation. Curr Behav Neurosci Rep. 2014;1(2):64-73. REFERENCE #2: Parhizgar F, Nugent K, Raj R. Obstructive sleep apnea and respiratory complications associated with vagus nerve stimulators. J Clin Sleep Med. 2011 Aug 15;7(4):401-7. REFERENCE #3: Ebben MR; Sethi NK; Conte M; Pollak CP; Labar D. Vagus nerve stimulation, sleep apnea, and CPAP titration. J Clin Sleep Med. 2008;4(5):471–473. DISCLOSURES: No relevant relationships by Jovica Veljanovski, source=Web Response No relevant relationships by Joshua Won, source=Web Response

Mirtazapine reduces susceptibility to hypocapnic central sleep apnea in males with sleep-disordered breathing: a pilot study.

Studies in humans and animal models with spinal cord injury (SCI) have demonstrated that medications targeting serotonin receptors may decrease the susceptibility to central sleep-disordered breathing (SDB). We hypothesized that mirtazapine would decrease the propensity to develop hypocapnic central sleep apnea (CSA) during sleep. We performed a single-blind pilot study on a total of 10 men with SDB (7 with chronic SCI and 3 noninjured) aged 52.0 ± 11.2 yr. Participants were randomly assigned to either mirtazapine (15 mg at bedtime) or a placebo for at least 1 wk, followed by a 7-day washout period before crossing over to the other intervention. Split-night studies included polysomnography and induction of hypocapnic CSA using a noninvasive ventilation (NIV) protocol. The primary outcome was CO2 reserve, defined as the difference between eupneic and end of NIV end-tidal CO2 ([Formula: see text]) preceding induced hypocapneic CSA. Secondary outcomes included controller gain (CG), other ventilatory parameters, and SDB severity. CG was defined as the ratio of change in minute ventilation (V̇e) between control and hypopnea to the change in CO2 during sleep. CO2 reserve was significantly widened on mirtazapine than placebo (-3.8 ± 1.2 vs. -2.0 ± 1.5 mmHg; P = 0.015). CG was significantly decreased on mirtazapine compared with placebo [2.2 ± 0.7 vs. 3.5 ± 1.9 L/(mmHg × min); P = 0.023]. There were no significant differences for other ventilatory parameters assessed or SDB severity between mirtazapine and placebo trials. These findings suggest that the administration of mirtazapine can decrease the susceptibility to central apnea by reducing chemosensitivity and increasing CO2 reserve; however, considering the lack of changes in apnea-hypopnea index (AHI), further research is required to understand the significance of this finding.NEW & NOTEWORTHY To our knowledge, this research study is novel as it is the first study in humans assessing the effect of mirtazapine on CO2 reserve and chemosensitivity in individuals with severe sleep-disordered breathing. This is also the first study to determine the potential therapeutic effects of mirtazapine on sleep parameters in individuals with a spinal cord injury.

842 PAP Therapy in a Pandemic: Management of Severe Mixed Apnea Predominant OSA &amp; CSA during the COVID-19 Pandemic

IntroductionIntroduction/Background: A new protocol and standard of care was created amidst the COVID-19 Pandemic that began in 2020. Traditional split night studies fell out of favor and were replaced by solely diagnostic studies with placement on Auto-PAP therapy if treatment of sleep disordered breathing was required. Some patients, however, required a more tailored approach if diagnostic polysomnogram (PSG) was particularly concerning. Our case report describes the treatment of a patient with severe Mixed Apnea Predominant Obstructive Sleep Apnea (OSA) with accompanying Central Sleep Apnea (CSA) using COVID-19 Precautions.Report of case(s)Case Description: A 48 year old AAM patient with a PMH of HTN, pre-diabetes, GERD, obesity and tobacco abuse initially presented to Sleep Medicine in late January 2020 with complaints of snoring, witnessed apneas, waking up gasping, excessive daytime sleepiness, fatigue, and non-restorative sleep for many years with ESS 24 and FSS 48 on initial evaluation. Diagnostic PSG showed AHI 76.9 with O2 desaturation to 59% and demonstrated the presence of severe Mixed Apnea predominant OSA and CSA with worsening during REM sleep. Because of the severity, he underwent a PAP titration in August 2020 using the AASM COVID-19 sleep study precautions which included use of a negative pressure room. Optimal control of snoring, apneic respiratory events and oxygen desaturations was achieved at 14 cm H2O in the supine body position during REM sleep. Follow up with Sleep Medicine in October and December 2020 showed objective compliance over a 30 day period not completely at goal due to issues with mask desensitization and sleep hygiene, however the patient subjectively reported that he noticed great improvement in snoring, excessive daytime sleepiness and fatigue.Conclusion: Discussion/ConclusionWith a diagnosis of Severe Mixed Apnea Predominant OSA as well as CSA noted during the study, the differential diagnosis included CHF, Chiari malformation, opioid abuse and idiopathic CSA as the cause. Despite a dangerous pandemic, appropriate therapy for certain patients must still be attained. Special protocols developed during the COVID-19 Pandemic allowed for our patient to receive adequate treatment, while ensuring the safety of all involved.Support (if any)References COVID 19: FAQs for Sleep Clinicians. AASM official website. https://aasm.org/covid-19-resources/covid-19-faq/

860 Variable Sleep Apnea Syndromes Complicated by Neurosurgeries in a Patient with Chiari Malformation Type 1

Abstract Introduction Chiari malformations (CM) are congenital conditions defined by craniocervical junction anatomic anomalies with downward displacement of cerebellar structures. Sleep-disordered breathing (SDB) including obstructive sleep apnea (OSA), bradypnea, central sleep apnea (CSA), and hypoventilation are described in CM patients. Report of case(s) 31-year-old male with history of CM type 1 presented to the sleep medicine clinic for management of OSA and CSA diagnosed at age 16. PSG showed an apnea-hypopnea index (AHI) of 14.2, RDI of 29, and no central events. He was started on auto-CPAP with pressures of 5–20 with subsequent visits showing high residual AHI. A subsequent CPAP-titration study resulted in a pressure of 16cm H2O yielding AHI of 0. CPAP pressure was fixed, but a high residual AHI persisted despite excellent compliance. A split-night study resulted in a BiPAP prescription, for which a titration study noted PAP-emergent CSA. He was started on auto Bilevel with IPAP of 30, EPAP of 8 and backup rate of 12bpm. Despite treatment, elevated AHI persisted so he was switched to adaptive servo-ventilation (ASV) with nightly oxygen blended in resulting in controlled complex sleep apnea. SDB management was complicated by multiple neurosurgical decompressions. During the most recent procedure, he was found to have syringomyelia, syringobulbia, and a mass at the brainstem. Surgery, including placement of a 4th ventricle stent and mass excision, initially led to a decrease of residual AHI to a low of 0.7, before progressively increasing to 15. A repeat PSG demonstrated severe OSA (AHI of 35), without evidence of CSA or nocturnal hypoventilation. ASV was resumed and patient’s AHI progressively decreased to an average of 8, with improvement in his sleep apnea symptoms. Conclusion SDM in CM patients can be explained by condition-related anatomical changes and depression of respiratory centers due to possible extrinsic compression leading to complex sleep apnea presentations. While it is unclear why this patient’s sleep apnea improved then worsened after his latest decompression surgery, we believe that CSF recirculation and postoperative inflammation may be responsible. Close monitoring of SDB in patients with CM is important as they may require advanced therapies for proper control. Support (if any):

Sleep Architecture in Children With Down Syndrome With and Without Obstructive Sleep Apnea.

To characterize polysomnographic sleep architecture in children with Down syndrome and compare findings in those with and without obstructive sleep apnea. Case series with retrospective review. Single tertiary pediatric hospital (2005-2018). We reviewed the electronic health records of patients undergoing polysomnography who were referred from a specialized center for children with Down syndrome (age, ≥12 months). Continuous positive airway pressure titration, oxygen titration, and split-night studies were excluded. A total of 397 children were included (52.4% male, 81.6% Caucasian). Mean age at the time of polysomnography was 4.7 years (range, 1.4-14.7); 79.4% had obstructive sleep apnea. Sleep variables were reported as mean (SD) values: sleep efficiency, 85% (11%); sleep latency, 29.8 minutes (35.6); total sleep time, 426 minutes (74.6); rapid eye movement (REM) latency, 126.8 minutes (66.3); time spent in REM sleep, 22% (7%); arousal index, 13.3 (5); and time spent supine, 44% (28%). There were no significant differences between those with obstructive sleep apnea and those without. Sleep efficiency <80% was seen in 32.5%; 34.3% had a sleep latency >30 minutes; 15.9% had total sleep time <360 minutes; and 75.6% had an arousal index >10/h. Overall, 69.2% had ≥2 metrics of poor sleep architecture. REM sleep time <20% was seen in 35.3%. REM sleep time decreased with age. In children with Down syndrome, 32.5% had sleep efficiency <80%; 75.6% had an elevated arousal index; and 15.9% had total sleep time <360 minutes. More than a third of the patients had ≥3 markers of poor sleep architecture. There was no difference in children with or without obstructive sleep apnea.

0898 The Accuracy Of Split-night Study In Assessing Obstructive Sleep Apnea (OSA) In Children And Adolescents

Abstract Introduction Split-night polysomnography (PSG) can be used for the diagnosis of OSA, if clinically appropriate, per AASM recommendation based on adult data. However, there are limited data in pediatric population. The aim of our study is to assess the accuracy of split-night-PSG compared with a full-night-PSG in children with OSA. Methods A retrospective review was performed in children and adolescents who were diagnosed with OSA during a diagnostic PSG (oAHI &amp;gt;1). Sleep and respiratory parameters from the full-night-PSG(F) were compared with the first three hours of the same PSG(S). Subgroup analysis was performed for age and OSA severity. The results were reported as mean±SD. All variables were compared with paired T-test. Results 226 met the criteria for entry into analysis. The mean age was 7.8y±5.8. For the whole cohort, there were no significant differences in the mean AHI and oAHI [7.3±11.7(F)vs6.9±13.9(S),p=0.26] between full-night and split-night studies. Subgroup analysis revealed that children aged 2-12 yo (n=120) had significant differences in the mean AHI [6.1±7.1(F)vs4.8±6.4(S)p=0.002] and the mean oAHI [4.8±5.6(F)vs3.9±5.4(S)p=0.03]. In addition, subgroup analysis of mild OSA (n=137) showed a significant difference in the mean AHI (p=0.006), but not in the mean oAHI (p=0.08). There were no significant differences in the mean AHI and oAHI in the moderate to severe OSA group. Based on the first 3 hours of PSG, 16.8%(n=38) of patients were inaccurately classified to have no OSA, while the severity was misclassified in 37.6%(n=85) of patients (underestimated in 30%(n=68) and overestimated in 7.5%(n=17)). Conclusion Although there were no differences in the mean AHI and oAHI, split-night-PSG misclassified diagnosis and severity in a significant proportion of our pediatric cohort. In addition, the accuracy of split-night-PSG is influenced by age and severity of OSA. Further studies are needed to identify factors that play a role in these differences. Support Cincinnati Children’s Hospital, Children’s Foundation

0348 Sleep EEG-Based Brain Age Index is Reduced Under Continuous Positive Airway Pressure Treatment

Abstract Introduction Continuous positive airway pressure (CPAP) is a treatment for apnea. With long-term CPAP, changes in electroencephalogram (EEG) include increased delta power (1 - 4Hz) and sigma power (11 - 15Hz, spindle). However, the short-term EEG response to CPAP in a split-night study is less quantified. We recently developed a “brain age” model using sleep EEG features. The brain age index (BAI) is defined as the difference between chronological age and brain age (BA - CA). Here we first quantify how BAI changes during CPAP in the same patient, and then investigate how much brain age features during the diagnostic part can predict the reduction in apnea-hypopnea index (AHI) during CPAP. Methods The dataset consisted of 160 subjects. The average age was 59 years with 53% male, 24% female and 23% unknown. We extracted 480 features including band powers, and then computed the BAIs for both diagnostic and CPAP parts. To predict the reduction in AHI during CPAP, we fit a Bayesian regression model using the brain age features, demographics, and sleep parameters during the diagnostic part, and assessed the feature importance using dominance analysis. Results The BAI from the diagnostic part is significantly reduced compared to BAI during CPAP for the same subject (paired t-test, p &amp;lt; 0.01). The diagnostic part has an average BAI 2.24 years; and the CPAP part -4.75 years. The brain age features that are increased during CPAP include sigma powers in N2 and N3. The prediction of AHI reduction has Pearson’s correlation 0.85. The features predictive of reduced AHI are the diagnostic AHI (explained variance 69%), followed by high/low waveforms during N2 (e.g. K-complex, measured by kurtosis) (8.6%), delta power during REM (4.5%) and N1 (2%). The feature predictive of increased AHI is frontal alpha power during quiet awake (2.6%). Conclusion The average BAI is reduced during CPAP. BAI provides a novel view of the acute response to CPAP in sleep EEG. Future study with more CPAP failure patients has the potential of predicting CPAP failure. Support MBW is supported by Glenn Foundation for Medical Research. RJT is supported by Category I AASM Foundation.

0590 Reliability of Simple Sleep Evaluation Device at Split-Night Polysomnography

Abstract Introduction Watch-PAT is a sleep evaluation device that measures the peripheral blood volume continuously with a probe attached to a fingertip and does not use an electroencephalogram or a nasal cannula. There has been no report on the usefulness of watch-PAT to determine the apnea diagnosis and continuous positive airway pressure (CPAP) use effects in split-night sleep study. Methods The consent of the study was obtained. Watch-PAT was simultaneously worn on a patient admitted for split-night polysomnography. The apnea-hypopnea index (AHI) obtained from PSG and the pAHI gained from the watch-PAT were measured when not using CPAP and when using CPAP respectively. And also we examined whether the reduction rates of AHI and pAHI could be correlated. Results 38 subjects (32 men, age 55 ± 13 years old). BMI 28.3 ± 5.7 kg / m2. When CPAP was not used, AHI was 57.2 ± 23.3 / h and pAHI was 50.8 ± 20.3 / h (r = 0.93, p &amp;lt; 0.0001), when CPAP was used, AHI was 5.2 ± 4.5 /h and pAHI was 6.2 ± 4.5 h (r = 0.82, p &amp;lt; 0.0001), AHI reduction rate was 90.4 ± 8.0% and pAHI reduction rate was 85.4 ± 14.6% (r = 0.76, p &amp;lt; 0.0001). Conclusion It was suggested that Watch-PAT had a good correlation with AHI at split night-sleep study. Support None

0704 Treatment-emergent Central Sleep Apnea Predicts Residual Respiratory Instability During Cpap Use At 6 Months

Abstract Introduction The prevalence, severity, significance, and predictors of residual sleep apnea during use of continuous positive airway pressure (CPAP) remain uncertain. High loop gain is associated with or induces periodic breathing and central sleep apnea (CSA). Treatment-emergent CSA (TE-CSA) is often considered a transient phenomenon of no long-term clinical significance. Standard polysomnographic features were assessed as risk factors for high residual apnea during compliant CPAP use. Methods Patients with sleep apnea (mean AHI 53.6, SD:33/hour of sleep) who underwent split night studies were prospectively entered in a database. They were all treated with positive airway pressure at the Beth Israel Deaconess Medical Center (Boston) and tracked by the EncoreAnywhere system. Machine detected AHI (AHIm) was extracted for a week average at month 6. The manual scored AHI(AHIs) was calculated from the last waveform graph during every month. Logistic regression assessed predictors of elevated automated (5 or greater) or manual (10 or greater) residual events//hour of use. Results A total of 69 CPAP compliant (average of at least 4 hours) subjects were analyzed. Age: 59.5 (range 17-81), gender: 47/69 male. 44/69 had an elevated manual AHI, while 20/69 had an elevated autodetected AHI. The only predictors of high residual apnea were TE-CSA (5 or more central apneas and hypopneas/hour of sleep): Odds Ratio 3.6 (CI: 1.07-12-3), p: 0.39. and the treatment component arousal index: Odds Ratio 1.06 (CI: 1.01-1.11), p: 0.018. Machine estimated AHI, which under-detected events by a factor of 3 or more, was not associated with any measure. Conclusion Residual apnea is common after 6 months of compliant CPAP use, and the only predictors identified were TE-CSA and treatment component arousal index. Support This study is supported by American Academy of Sleep Medicine Foundation, Category-I award to RJT

0968 Sleep-disordered Breathing In Schaaf-yang Syndrome

Abstract Introduction Schaaf-Yang Syndrome (SYS) is a genetic disorder caused by truncating variants in the MAGEL2 gene located in the maternally imprinted, paternally expressed Prader-Willi syndrome (PWS) region at 15q11-13. The SYS phenotype shares features with PWS, a disorder with known high incidence of central and obstructive sleep apnea (OSA). However the spectrum of sleep-disordered breathing in SYS has not been described. Methods We performed a retrospective analysis of polysomnograms from 22 of the known 115 patients with molecular diagnosis of SYS. Sleep characteristics including total sleep time, latency, efficiency, % sleep stages, apnea-hypopnea index (AHI), obstructive index, central index, and oxygenation were analyzed for the whole group and by truncation location (c.1996dupC variants [n=11] or other locations [n=11]). Only the initial diagnostic study or initial diagnostic portion of a split-night study was used in analysis (analytic n=21). Results We collected 33 sleep study reports from 22 patients, ages 2 months - 18.5 years. Mean analyzed sleep time was 357 minutes (129-589 min) with mean sleep efficiency of 71.45% (45-94%) and sleep latency of 24.8 minutes (0-146 min). The mean apnea-hypopnea index (AHI) was 19.1/hr (0.9 -49/hr) with mean obstructive AHI of 16.3 (0.6-49/hr). Mean central index was 2.8/hr (0-14/hr). 18/21 (86%) were diagnosed with OSA, and 13/21 (62%) with moderate or severe OSA (oAHI &amp;gt;5/hr). Central sleep apnea was diagnosed in 2/21 (9.5%). 15 studies reported periodic limb movement index (PLMI) with mean of 7.8 (0-67/hr) and 4/15 (26%) with PLMI &amp;gt;5. Comparison of genotype groups did not reveal any difference in presence of OSA or severity of OSA. Conclusion OSA is frequently identified on polysomnography in patients with SYS. Central sleep apnea is less common, which is in contrast to PWS. The majority of patients with OSA had moderate or severe OSA, and 47% had severe OSA. Support N/A

Impact of CPAP on LF Power, HF Power and LF–HF Ratio in Patients with Severe OSA During Split Night Study

Obstructive sleep apnea (OSA) is implicated in the pathogenesis of cardiovascular diseases such as coronary artery disease, rhythm disturbances, heart failure, and stroke. Increased sympathetic activity and decreased parasympathetic activity have been implicated as the causes for the above. Effective treatment with positive airway pressure (PAP) significantly reduces the cardiovascular outcomes associated with OSA. Treatment of OSA with positive airway pressure (PAP) therapy has resulted in improved risk of cardiovascular morbidity, possibly by changing the sympathetic and parasympathetic drive. Although long-term effects of this therapy have been observed in the previous studies, we have explored the split night effect of PAP therapy on the sympathetic and parasympathetic activities in our study. Fourteen patients with severe OSA who had split night study were enrolled. All were well controlled with continuous positive airway pressure (CPAP) therapy. 10 min epoch of electrocardiogram (ECG) was selected in the diagnostic phase as well as during the CPAP usage in stage 2 and 3 sleep. Low-frequency (LF), high-frequency (HF) power and LF–HF ratios were calculated and compared for sleep stages 2 and 3 separately in the diagnostic and titration phases. Higher LF–HF ratio was seen in the diagnostic phase which significantly reduced after CPAP therapy for both sleep stages 2 and 3 (p < 0.05). A significant decrease in LF–HF ratio was seen in the patients after the use of CPAP for more than 4 h. This could have great impact on the cardiovascular system.

Sleep apnea: Tracking effects of a first session of CPAP therapy by means of Granger causality

Connectivity between physiological networks is an issue of particular importance for understanding the complex interaction brain-heart. In the present study, this interaction was analyzed in polysomnography recordings of 28 patients diagnosed with obstructive sleep apnea (OSA) and compared with a group of 10 control subjects. Electroencephalography and electrocardiography signals from these polysomnography time series were characterized employing Granger causality computation to measure the directed connectivity among five brain waves and three spectral subbands of heart rate variability. Polysomnography data from OSA patients were recorded before and during a first session of continuous positive air pressure (CPAP) therapy in a split-night study. Results showed that CPAP therapy allowed the recovery of inner brain connectivities, mainly in subsystems involving the theta wave. In addition, differences between control and OSA patients were established in connections that involve lower frequency ranges of heart rate variability. This information can be potentially useful in the initial diagnosis of OSA, and determine the role of cardiac activity in sleep dynamics based on the use of three subbands of heart rate variability.

Supplemental Oxygen for Treatment of Infants With Obstructive Sleep Apnea.

Supplemental oxygen has been shown to decrease the frequency of obstructive respiratory events during sleep, but may result in alveolar hypoventilation. Limited information exists on the effect of supplemental oxygen on sleep and respiratory events in infants with obstructive sleep apnea (OSA). We conducted a retrospective study of infants with OSA who had sleep studies performed from 2007-2012. All infants underwent a room air diagnostic sleep study (RA-PSG), followed by a sleep study while breathing supplemental oxygen via nasal cannula (O₂-PSG) on a separate night. Infants with split-night studies or with inadequate sleep time were excluded. Fifty-nine infants met criteria for entry into analysis. The mean age of infants at the time of RA-PSG was 13.0 ± 11.7 weeks and at O₂-PSG was 15.4 ± 13.0 weeks. The obstructive AHI decreased from 19.7 ± 13.0 during RA-PSG to 10.6 ± 11.7 during O₂-PSG (P < .001). The duration of longest obstructive apnea increased from 11.0 ± 4.2 seconds to 13.4 ± 7.4 seconds (P = .01). The lowest saturation associated with obstructive apneas increased from 80.7 ± 6.8% to 90.0 ± 6.7% (P < .001). Carbon dioxide data showed no difference in ventilation after supplemental oxygen administration. There was no significant change in the spontaneous arousal index, however, the percentage of respiratory events associated with arousal increased from 20.7 ± 11.1% to 35.7 ± 19.7% (P < .001). Infants with OSA who received supplemental oxygen had a significant decrease in the frequency of obstructive respiratory events and improved oxygenation without adverse effect on alveolar ventilation. These data suggest that supplemental oxygen may be an effective treatment for infants with OSA who are not good candidates for continuous positive airway pressure or surgery. Brockbank J, Astudillo CL, Che D, Tanphaichitr A, Huang G, Tomko J, Simakajornboon N. Supplemental oxygen for treatment of infants with obstructive sleep apnea. J Clin Sleep Med. 2019;15(8):1115-1123.

Useful variables during wake and sleep for prediction of positive airway pressure in obstructive sleep apnea titration

BackgroundPositive airway pressure is the main treatment modality in obstructive sleep apnea. The level of pressure needed for each patient is defined by a positive airway pressure titration study. Predicting those who need higher pressure or bi-level instead of continuous pressure is of a great clinical significance. This study was designed to evaluate whether voluntary breath-holding maneuver could predict Bilevel Positive Airway Pressure (BiPAP) or Continuous Positive Airway Pressure (CPAP) as the final optimal pressure in a split night study of patients with obstructive sleep apnea. Polysomnography (PSG) parameters specially oxygen saturation (SaO2) during non-rapid eye movement (NREM), rapid eye movement sleep (REM), and duration of REM in diagnostic part may help determine the type of devices as soon as possible in split night study.MethodsThe present research was conducted as a cross-sectional study of adults diagnosed as obstructive sleep apnea patients undergoing positive airway pressure (PAP) titration. Demographic, anthropometric, and polysomnographic data were collected. Patients were instructed to hold their breath as long as they could after five tidal breaths in the supine position. Baseline, post breath-holding phase, and recovery SaO2 were recorded. These data were used to predict the pressure level and type of device.ResultsSeventy-eight participants (56.4% male) with the mean age of 55.7 ± 13.9 years were included in the study. Mean and SD of apnea hypopnea index (AHI) and oxygen desaturation index (ODI) were 55.9 ± 34.4 and 38.3 ± 24 per hour, respectively. Most of the participants (65.3%) were categorized as CPAP group. CPAP and BiPAP groups were similar in terms of age, gender distribution, body mass index (BMI), neck circumference, and certain polysomnographic variables. Voluntary breath-holding maneuver showed a significant correlation between minimum SaO2 and the need for changing to BiPAP during titration. Baseline and post breath-holding SaO2 were not significantly lower in either group. NREM minimum SaO2 and REM duration were the statistically significant correlated variables that predicted the need for BiPAP.ConclusionMinimum oxygen following voluntary breath-holding maneuver along with higher BMI and larger neck circumference are predictors of the need to use BiPAP. Shorter REM duration and NREM minimum SaO2 were other predictors of higher chance of BiPAP during titration of the present OSA participants.