Testing For Obstructive Sleep Apnea Research Articles

Evaluation of Complex Upper Airway Obstruction in Children Using Cine-MRI: A Single-Center Experience and Literature Review.

Introduction Polysomnography (PSG) is considered the gold standard diagnostic test for obstructive sleep apnea (OSA) in children. However, the anatomic location of upper airway obstruction in these patients cannot be determined by PSG, especially in children with complex upper airway obstruction. CT imaging and endoscopic evaluation have been proposed for the evaluation of upper airways in these children. However, cinematic magnetic resonance imaging (Cine-MRI) is a safer, less invasive, and potentially more useful tool for dynamic and anatomical evaluation of upper airways. We here describe the diagnostic outcomes of Cine-MRI in our cohort of children with OSA and suspected complex upper airway obstruction. Methods A retrospective chart review of clinical and radiological data of all children with PSG confirmed diagnosis of OSA and who underwent upper airway evaluation using Cine-MRI. Upper airways were evaluated at three different levels: nasopharynx, oropharynx, and supraglottic, during both inspiration and expiration. Fractional collapse (FC) at different levels was used to evaluate dynamic airway collapse and was defined as the difference between maximum and minimum airway dimensions divided by the maximum dimensions. Results Eight children (five females and three males) were included. Median age was 8.5 months (range: one month to 16 years). Cine-MRIs identified upper airway obstruction in all patients. Additionally, 50% of the patients had more than one level of obstruction, mainly the nasopharynx and oropharynx. There was a positive correlation between the apnea-hypopnea index (AHI) and FC in the anteroposterior dimension at the nasopharyngeal and the oropharyngeal levels, but it did not reach statistical significance. However, there was a statistically significant negative correlation between AHI and FC in the transverse dimension at the oropharyngeal level. Cine-MRI was helpful in continuous positive airway pressure (CPAP) titration in two patients and was helpful in planning surgical intervention in two patients. Conclusion Cine-MRI is a helpful diagnostic tool in evaluating patients with complex upper airway obstruction and can direct potential surgical and non-surgical intervention in pediatric patients with complex upper airway obstruction.

Abstract 16126: Sex Differences in the Relationship Between Left Ventricular Global Longitudinal Strain and Abnormal Myocardial Flow Reserve in a Patient Population With Sleep Disordered Breathing

Introduction: Obstructive sleep apnea (OSA), a form of sleep disordered breathing (SDB), is associated with abnormal myocardial flow reserve (MFR), a precursor to heart failure with preserved ejection fraction (HFPEF). Sex differences have been reported in the prevalence of abnormal MFR and OSA. However, it is unknown if there are sex differences in the relationship between left ventricular (LV) global longitudinal strain (GLS) and abnormal MFR in a patient population with SDB. Methods: We compared LV GLS among patients in our institution who had sleep testing for obstructive sleep apnea (OSA), cardiac PET stress test and an echocardiogram between 2015 and 2019. We reprocessed the echocardiograms using a vendor neutral software to obtain the two-dimensional LV GLS. Results: Among the 148 participants, 59% were female. Compared with females, males had lower BMIs, a higher prevalence of prior myocardial infarction or revascularization, and a greater severity of nocturnal airway obstruction and hypoxia. Males also had a greater proportion with abnormal LV GLS (≥ -17). See Table. The prevalence of abnormal MFR (< 2.0) was higher among participants with abnormal LV GLS ( P = 0.031). This association was persistent among males but was lost among females (see Figure ). In age and sex adjusted logistic regression persons with abnormal LV GLS had 2X the odds of abnormal MFR (OR 2.3; 95% CI: 1.02 - 5.03). Among males, this association was significant (OR 4.8; 95%CI:1.5 - 13.7). No association observed among females. Formal interaction analyses did not meet statistical significance ( P int = 0.106). Conclusions: In this patient population with SDB, there was a significant association between LV GLS and abnormal MFR. The sex differences in the relationship may be due to differences in the severity of OSA and prevalence of ischemic heart disease. Future studies should clarify these relationships and elucidate the drivers of the sex disparities observed in these findings.

0566 The Usefulness of ApneaLinkTM as a Screening Test for Diagnosis of Obstructive Sleep Apnea

Abstract Introduction To investigate the usefulness of ApneaLinkTM as a screening test for obstructive sleep apnea by analyzing the correlation between ApneaLinkTM and polysomnography (PSG). Methods From January 1, 2018 to December 31, 2020, patients who visited the sleep clinic with snoring, sleep apnea, and excessive daytime sleepiness at the otolaryngology department of this hospital were subjected to both standard sleep PSG and ApneaLinkTM. Correlations of Apnea-Hypopnea Index (AHI) and Respiratory Disturbance Index (RDI) in standard PSG with AHI and Risk Indicator (RI) in ApneaLinkTM were investigated. To determine the usefulness of ApneaLinkTM as a screening test for patients with moderate or severe sleep apnea, cut-off values of AHI and RI of ApneaLinkTM were determined using receiver operating characteristic (ROC) curves. Results The correlation coefficient between AHI in PSG and AHI or RI in ApneaLinkTM was both 0.647, showing a high positive correlation. The correlation coefficient between RDI in PSG and AHI or RI in ApneaLinkTM was both 0.637, showing a high positive correlation. When the cut-off value of AHI with the ApneaLinkTM test was 19.0, it showed a sensitivity of 76.29% and a specificity of 78.95%, which could be expected to produce more than 15 of RDI in PSG. Conclusion Through this study, it was found that ApneaLinkTM could be used as a screening test for obstructive sleep apnea. Support (if any)

The Effect of Self-Reported Visual Impairment and Sleep on Cognitive Decline: Results of the Hispanic Community Health Study/Study of Latinos.

Visual impairment could worsen sleep/wake disorders and cognitive decline. To examine interrelations among self-reported visual impairment, sleep, and cognitive decline in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Miami-site. HCHS/SOL Miami-site participants ages 45-74 years (n = 665) at Visit-1, who returned for cognitive test 7-years later (SOL-INCA). Participants completed the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ), validated sleep questionnaires and test for obstructive sleep apnea (OSA) at Visit-1. We obtained verbal episodic learning and memory, verbal fluency, processing speed, and executive functioning at Visit-1 and at SOL-INCA. Processing speed/executive functioning were added to SOL-INCA. We examined global cognition and change using a regression-based reliable change index, adjusting for the time lapse between Visit-1 and SOL-INCA. We used regression models to test whether 1) persons with OSA, self-reported sleep duration, insomnia, and sleepiness have an increased risk for visual impairment, 2a) visual impairment is associated with worse cognitive function and/or decline, and 2b) sleep disorders attenuate these associations. Sleepiness (β= 0.04; p < 0.01) and insomnia (β= 0.04; p < 0.001) were cross-sectionally associated with visual impairment, adjusting for sociodemographic characteristics, behavioral factors, acculturation, and health conditions. Visual impairment was associated with lower global cognitive function at Visit-1 (β= -0.16; p < 0.001) and on average 7-years later (β= -0.18; p < 0.001). Visual impairment was also associated with a change in verbal fluency (β= -0.17; p < 0.01). OSA, self-reported sleep duration, insomnia, and sleepiness did not attenuate any of the associations. Self-reported visual impairment was independently associated with worse cognitive function and decline.

Should testing for obstructive sleep apnea be offered routinely to older family medicine patients? A prospective cohort study

ABSTRACT In our previous studies, we offered older family medicine patients testing for obstructive sleep apnea (OSA) and discovered that 80% of patients who accepted, were later diagnosed with unsuspected OSA. In the present study, we followed such patients for 3 years of usual treatment. The goals were to (1) observe whether wider testing for OSA would increase case recognition and treatment uptake; (2) identify symptom and health characteristics associated with diagnosis and treatment efficacy. 101 women and 75 men (>45 years) recruited from family medicine clinics completed questionnaires, polysomnography and consented to chart review (Time 1). Participants with OSA were offered treatment and follow-up with a sleep medicine specialist. All were re-evaluated after 3 years (Time 2). At Time 1, 93% of participants received a diagnosis of OSA. Of these, 53 initiated treatment (46 PAP therapy); at Time 2, 24 PAP users met criteria for adherence. PAP-adherent participants had worse OSA and worse reported symptoms at Time 1 than non-adherent participants. At Time 2, PAP-adherent participants improved on insomnia and daytime symptoms compared to non-adherent participants who showed no change. Adherent and non-adherent participants showed no difference in health indices at Time 1 and no change at three-year follow-up. Benefits of treatment included improvements in co-morbid insomnia and daytime functioning; however, offering wider testing for OSA to older, family medicine patients yielded a high rate of diagnosis but low treatment adoption and adherence. Therefore, a cost-effective strategy would identify and support those likely to adopt and adhere to treatment.

Sex-specific differences in diagnostic approaches of inpatient sleep testing for obstructive sleep apnea

BackgroundFew studies have investigated sex-specific disparities in inpatient sleep testing. We postulate that women are more likely to have a milder degree of obstructive sleep apnea (OSA) and lower extent of hypoxia on Type III sleep studies versus polysomnography (PSG). Patients and methodsThe Cleveland Clinic Sleep laboratory registry was leveraged to identify all adult inpatient sleep studies performed for OSA. Demographics, comorbidities, and sleep study measures were collected and compared by sex and sleep study type. Logistic regression was used to examine sleep study type predictive of OSA (apnea hypopnea index [AHI; ≥5, ≥15 and ≥ 30]) and hypoxia, (median percentage of sleep time spent at <90% SaO2 [TST<90%,≥ 11%,] adjusted for covariates. ResultsThe sample 778 patients had a mean age of 56.1 ± 16.1 years; 44.5% were female and 72.2% Caucasian. At an AHI≥5, women showed an increase odds of OSA (adjusted, OR = 2.04,95%; CI:1.24–3.35, p = 0.005) with Type III sleep study vs PSG compared to men. At an AHI≥15, men had less odds of OSA (adjusted OR = 0.60,95%CI:0.39–0.90,p = 0.015) with Type III sleep study vs PSG compared to women (OR = 1.15,95%CI:0.72–1.85,p = 0.56), with an interaction p-value of 0.040. These results were attenuated when the analysis was restricted using the 3% hypopnea scoring rule. Men and women had higher odds of TST <90 ≥ 11% (OR:2.60,95%CI:1.60–4.21,p=<0.001; OR:3.46,95%CI:1.97–6.05,p < 0.001) with Type III sleep study versus PSG, albeit no sex-interaction was observed. ConclusionsThese results suggest that sex-specific differences in diagnostic performance of sleep testing type in the inpatient setting should be considered according to level of OSA severity, which are influenced by hypopnea-related desaturation extent.

Keep it simple: A novel technique for measuring airflow using a wireless patch

Despite the growing use of home sleep testing for obstructive sleep apnea (OSA), there are significant barriers that make it difficult for patients. This study aimed to evaluate a new set of wireless patches for the detection of OSA as compared to polysomnography (PSG) respiratory signals. Safety was also evaluated. Patients (n=25; mean age=51.3; SD=15.6) undergoing standard PSG evaluation for OSA wore 2 device patches applied on the chest and abdomen to provide surrogates of respiratory effort and derived airflow. Two sets of respiratory data (with common SpO2 and heart rate as a reference from PSG) were created, one from PSG and one from the device patches. Data were scored by a Registered Polysomnographic Technologist. Linear regression analyses and Bland-Altman plots were used to compare the two derived apnea-hypopnea indices (AHI). Bench testing was performed to determine whether the device patch respiratory signal accuracy remained consistent for different body characteristics. There was a significant correlation for AHI between the device patch and PSG (r=0.979; P < .001; 95% CI 0.952, 1.00). There were also significant correlations between PSG and the device patch for supine AHI (r=0.866, P < .001, 95% CI 0.610, 0.965) and nonsupine AHI (r=0.983; <0.001, 95% CI 0.954, 1.00). No differences in respiratory signal accuracy were found with bench testing comparison groups. These preliminary results suggest that the device patch may be an effective way to measure respiratory dynamics, including derived airflow, to evaluate OSA. Results show promise as a new innovative method for home sleep testing.

The Usefulness of ApneaLinkTM as a Screening Test for Diagnosis of Obstructive Sleep Apnea

Background and Objective To investigate the usefulness of ApneaLinkTM as a screening test for obstructive sleep apnea by analyzing the correlation between ApneaLinkTM and polysomnography (PSG).Methods From January 1, 2018 to December 31, 2020, patients who visited the sleep clinic with snoring, sleep apnea, and excessive daytime sleepiness at the otolaryngology department of this hospital were subjected to both standard sleep PSG and ApneaLinkTM. Correlations of Apnea-Hypopnea Index (AHI) and Respiratory Disturbance Index (RDI) in standard PSG with AHI and Risk Indicator (RI) in ApneaLinkTM were investigated. To determine the usefulness of ApneaLinkTM as a screening test for patients with moderate or severe sleep apnea, cut-off values of AHI and RI of ApneaLinkTM were determined using receiver operating characteristic (ROC) curves.Results The correlation coefficient between AHI in PSG and AHI or RI in ApneaLinkTM was both 0.647, showing a high positive correlation. The correlation coefficient between RDI in PSG and AHI or RI in ApneaLinkTM was both 0.637, showing a high positive correlation. When the cut-off value of AHI with the ApneaLinkTM test was 19.0, it showed a sensitivity of 76.29% and a specificity of 78.95%, which could be expected to produce more than 15 of RDI in PSG.Conclusions Through this study, it was found that ApneaLinkTM could be used as a screeningtest for obstructive sleep apnea.

0370 Polysomnography following an indeterminate HSAT: Low Compliance with AASM Guidelines

Abstract Introduction Home sleep apnea test (HSAT) provides a low risk, cost-effective, and convenient diagnostic test for obstructive sleep apnea (OSA) in adult patients. However, in situations where HSAT are inconclusive, technically inadequate, or produce a negative result, the American Academy of Sleep Medicine (AASM) strongly recommends that a polysomnography (PSG) be performed. In this study, we evaluate whether patients are likely to comply with receiving a follow-up PSG following an indeterminate HSAT to rule out any presence of OSA and assess the demographic characteristics of individuals who are more likely to follow the AASM guidelines. Methods In order to assess routine compliance with the AASM follow-up guidelines, we have conducted an observational study with N=3,049 patients that received a HSAT in 2019 from 6 independent AASM accredited sleep centers across the U.S. The patient sample included 39.8% female and 60.2% male. 30.34% from the 19-44 age group, 47.2% from the 45-64 age group, and 21.2% from the 65-84 age group. Furthermore, 33% of the patients received a negative HSAT and were advised for a follow-up PSG. Results 14.8% of patients who received a negative HSAT in 2019 underwent a follow-up PSG by the end of 2021. Male patients and patients who are younger in age were more likely to follow the AASM guidelines. 16.4% of male patients and 9% of female patients who received a negative HSAT underwent a follow-up PSG. 17.7% of patients aged 19-44 who received a negative HSAT received a follow-up PSG, while only 11.1% of patients aged 45-64, and 7.6% of patients aged 65-84 conformed with the AASM guidelines and followed-up with a PSG. Conclusion The overall percentage of patients who comply with the AASM guidelines is relatively low at 14.8%. Emphasis should be put on patient outreach and education to improve this statistic. Such endeavors may try to target female and older patients who appear to be slightly less compliant with AASM guidelines. Simultaneously, more attempts should be made to improve HSAT to increase OSA specificity and decrease the necessity for a follow-up PSG, as this AASM guideline is often overlooked by patients. Support (If Any)

Multiple-access versus telemedicine home-based sleep apnea testing for obstructive sleep apnea (OSA) diagnosis: a cost-minimization study.

PurposeThe aim of the present study was to compare two clinical pathways: the multiple-access outpatient pathway versus the telemedicine pathway.MethodsThe multiple-access outpatient pathway and the telemedicine pathway were both performed with WatchPAT and implemented in a real-life healthcare scenario, adopting a cost-minimization approach. A cost-minimization analysis was undertaken to assess the economic impact of the two alternatives. The cost analyses were performed in euros for the year 2021 adopting the patient, the hospital, and the societal perspectives. Given the chosen perspectives, direct medical costs, direct nonmedical costs, and indirect costs were considered. In addition, a univariate sensitivity analysis was conducted.ResultsFrom a hospital perspective, the telemedicine approach was estimated to cost €49 more than the multiple-access alternative. Considering the patient perspective, the telemedicine approach was estimated to cost €167 less than the multiple-access pathway. Considering the societal perspective, the telemedicine approach is estimated to cost €119 less than the multiple-access pathway.ConclusionThe adoption of telemedicine home sleep apnea testing could improve the efficiency of the healthcare processes if considering the direct and indirect costs incurred by patients and not only by healthcare providers.

422 Influence of Sex-Specific Differences in Inpatient Sleep Testing Approach for Diagnosis of Obstructive Sleep Apnea

Abstract Introduction Increased attention has been focused on sex-specific differences in approaches to diagnostic testing for obstructive sleep apnea (OSA) given differences in hypoxia, arousal thresholds and sleep state dependent influences, but with sparse data available for inpatient testing. We postulate that women are more likely to have a lesser degree of sleep apnea on inpatient home sleep apnea testing (HSAT) versus polysomnography (PSG). Methods The Cleveland Clinic Sleep Laboratory registry was queried for inpatient sleep testing (HSAT or PSG conducted over the last 15 years. Demographics, comorbidities, and sleep study (Nihon Kohden®) data were collated. Logistic regression was used to examine sleep study type predictive of OSA at various severity thresholds (apnea hypopnea index (AHI, 3 or 4% hypopnea rule)&amp;gt;5,&amp;gt;15 and &amp;gt;30 and hypoxia (11% (median) time spent with SaO2&amp;lt;90%) adjusted for age, race and body mass index and comorbidities (hypertension, coronary artery disease, arrhythmias, heart failure, diabetes, stroke, chronic obstructive pulmonary disease, mood disorders, respiratory failure and epilepsy with a sex interaction term) (OR, 95%CI presented). Results The analytic sample was comprised of 639 patients: age:55.8±16.3 years, 45% female, 73% Caucasian, BMI:37.5 ± 13.3kg/m2, 74% had OSA and 51% HSAT. Men had higher AHI:16.2 [5.9, 42.3] vs 8.2 [2.9, 20.7]p&amp;lt;0.001, higher arousal index:33.1[18.9,.54] vs 25.3 [15.6, 39.2]p=0.003. Women had higher BMI:40.2 ±14.7, vs 36 ±11.7kg/m2,p&amp;lt;0.001. Unlike AHI&amp;gt;5, at AHI&amp;gt;15, men had lower odds of OSA: OR=0.51:0.32–0.80,p=0.004 for HSAT versus PSG compared to women: OR=1.03:0.61–1.72,p=0.92; interaction p-value=0.046. Men had lower odds of OSA (AHI &amp;gt;30): OR=0.57(0.35,0.92,p=0.022) in HSAT vs PSG; albeit sex-interaction was not statistically significant. Men versus women had 2-versus 3-fold higher hypoxia ie. OR=2.04:1.22–3.41,p=0.006 in men undergoing HSAT versus PSG with strength of association higher in women: OR=3.03:1.68–5.46,p=0.001, interaction p-value=0.32 Conclusion We unexpectedly observe sex-specific differences in inpatient sleep testing such that men had an overall lower odds of detection of moderate to severe and OSA and nocturnal hypoxia relative to women with HSAT versus PSG. Future investigation focused on concurrent inpatient PSG and HSAT should verify these sex-specific findings and clarify potential biophysiologic rationale Support (if any) Transformative Neuroscience Research Development Program: Multimodal Neurocardiorespiratory Physiologic Sleep Signal Repository Transformative Resource Facilitating Transdisciplinary Research Opportunities

Translation and cross-cultural adaptation of the pediatric sleep questionnaire (PSQ*) into Brazilian Portuguese

IntroductionObstructive sleep apnea is a frequent entity in childhood that can lead to important consequences for the health and children's quality of live. Polysomnography is the gold-standard exam to diagnose obstructive sleep apnea, but it is expensive, complex, and poorly affordable in Brazil. The pediatric sleep questionnaire has shown to be a valuable screening test for obstructive sleep apnea. It is a simple questionnaire with good sensitivity and specificity compared to polysomnography in the countries where it has been validated. ObjectiveTranslation and cross-cultural adaptation of the pediatric sleep questionnaire (PSQ), into Brazilian Portuguese. MethodsThe translation of the PSQ into Brazilian Portuguese was carried out in accordance with good practices. The validated and adapted questionnaire was applied to parents/caregivers of 60 children (40 of them with obstructive sleep apnea and 20 controls) aged 2–18 years. Retest was applied to 30 children with obstructive sleep apnea. The following tests were performed: internal consistency, test–retest, validation of questionnaire (the latter by ROC curve). ResultsBrazilian PSQ has shown high internal consistency by Cronbach's alpha (0.86 for the total test, 0.83 for subscale “snoring”, 0.64 for “sleepiness” and 0.65 for “behavior”). Test–retest presented a correlation of 0.89 for subscale “snoring”, 0.93 for “sleepiness” and 0.86 for “behavior”. Accuracy by ROC curve was 0.99. Nine was considered the optimal value to discriminate patients with obstructive sleep apnea from controls, with a sensitivity of 0.92 and specificity of 1.0. ConclusionThe translation and cross-cultural adaptation of the PSQ into Brazilian Portuguese proved to be successful. In places with difficult access to polysomnography, PSQ can be a useful tool in screening and follow-up of children with obstructive sleep apnea.

Validation of noncontact cardiorespiratory monitoring using impulse-radio ultra-wideband radar against nocturnal polysomnography

Polysomnography (PSG) is a standard diagnostic test for obstructive sleep apnea (OSA). However, PSG requires many skin-contacted sensors to monitor vital signs of patients, which may also hamper patients' sleep. Because impulse-radio ultra-wideband (IR-UWB) radar can detect the movements of heart and lungs without contact, it may be utilized for vital sign monitoring during sleep. Therefore, we aimed to verify the accuracy and reliability of the breathing rate (BR) and the heart rate (HR) measured by IR-UWB radar. Data acquisition with PSG and IR-UWB radar was performed simultaneously in 6 healthy volunteers and in 15 patients with suspected OSA. Subjects were divided into 4 groups (normal, mild OSA, moderate OSA, and severe OSA) according to the apnea-hypopnea index (AHI). BRs and HRs obtained from the radar using a software algorithm were compared with the BRs (chest belt) and the HRs (electrocardiography) obtained from the PSG. In normal and in mild OSA, BRs (intraclass correlation coefficients R [ICCR] 0.959 [0.956-0.961] and 0.957 [0.955-0.960], respectively) and HRs ([ICCR] 0.927 [0.922-0.931] and 0.926 [0.922-0.931], respectively) measured in the radar showed excellent agreement with those measured in PSG. In moderate and severe OSA, BRs ([ICCR] 0.957 [0.956-0.959] and 0.873 [0.864-0.882], respectively) and HRs ([ICCR] 0.907 [0.904-0.910] and 0.799 [0.784-0.812], respectively) from the two methods also agreed well. The IR-UWB radar could accurately measure BRs and HRs in sleeping patients with OSA. Therefore, IR-UWB radar may be utilized as a cardiopulmonary monitor during sleep.

Correlation Between Oxygen Saturation and Pulse Tracing Patterns on Overnight Oximetry With Normal Desaturation Index Is an Independent Predictor of Obstructive Sleep Apnea.

Overnight pulse oximetry (OPO) is commonly used as a screening test for obstructive sleep apnea. Heart rate variability (HRV) correlates well with apnea-hypopnea index during polysomnography (PSG). We hypothesized that visual correlation of episodic increase in HRV with minimal oxygen desaturations on normal OPO (oxygen desaturation index less than 5 events/h) is predictive of OSA. A retrospective analysis of patients undergoing OPO and PSG in 1 year was performed. We included only OPO performed on room air and interpreted as normal. Visual correlation between simultaneous increase in HRV and minimal oxygen desaturation was independently assessed by three raters, resulting in the consensus agreement. The primary outcome was presence of OSA on the subsequent PSG. Of 936 patients with OPO and PSG, 109 patients had normal overnight oximetry study on room air. Of these, 65 (60%) were females, median (interquartile range) age was 54 years (44, 67), body mass index was 29 kg/m2 (25, 32), and the median oxygen desaturation index was 1.8 events/h (1, 2.7). Consensus agreement identified 54 patients with visual correlation between pulse and minimal oxygen desaturations. Thirty-two patients (29%) were found to have OSA on PSG, of which 24 (75%) could have been accurately predicted by the consensus agreement (odds ratio 4.70, 95% confidence interval 1.87-11.8, P < .001). When adjusted for pertinent clinical and demographic variables, consensus agreement was independently associated with diagnosis of OSA on subsequent PSG (odds ratio 5.6, 95% confidence interval 1.76-20.9, P = .003). Visual correlation between episodic increase in HRV and minimal oxygen desaturations on OPO is an independent predictor of OSA, and promising marker for clinical use.

Pediatric sleep-disordered breathing: an update on diagnostic testing.

Recent advances in diagnostic testing for obstructive sleep apnea in children have refined the standard tests while identifying several new tools that hold promise to radically change how we diagnose sleep apnea. Studies have demonstrated that the polysomnogram may be modified to permit home assessment of sleep disturbed breathing in children to ensure more widespread access to the test. Alternately, questionnaires, nocturnal oximetry, and diagnostic urinary biomarkers have shown great promise as both sensitive and specific tools to diagnose sleep apnea in children as well as track the severity of the disease. The gold standard polysomnogram has been refined to permit its application in a modified form at home and for brief examinations in children. This standard has been challenged on several fronts, including questionnaires, nocturnal oximetry, drug-induced sleep endoscopy, and noninvasive urinary biomarkers that may ultimately supplant polysomnography as the gold standard to diagnose obstructive sleep apnea syndrome in children.

Comparison of diagnostic reliability of out-of-center sleep tests for obstructive sleep apnea between adults and children

ObjectivesSleep studies for diagnosing obstructive sleep apnea (OSA) in children are laborious, expensive, inconvenient, and often not readily available. Out-of-center sleep test (OCST) devices have been studied for diagnosing OSA in adults, but few OCST studies have been done in children. The purpose of this study was to clarify the diagnostic reliability of OCST devices for children. MethodsOCSTs using pulse oximetry and in-laboratory polysomnography (PSG) were performed separately in 686 adults and 119 children. For each apnea–hypopnea index (AHI) measured with PSG, accuracy, sensitivity, specificity, positive/negative likelihood ratio (PLR/NLR), and positive/negative predictive value (PPV/NPV) were calculated for several cutoff values of 3% oxygen desaturation index (ODI) measured with OCST and analyzed. ResultsFor definitive diagnosis in adults, the specificity, PLR, and PPV with a cutoff value of OCST-ODI 20/h were 98.3%, 29.26, and 97.4%, respectively, to detect PSG-AHI ≥20/h. Corresponding values with a cutoff value of OCST-ODI 15/h were 99%, 46.19, and 99.6% to detect an AHI ≥5/h. For exclusive diagnosis (screening) in adults, sensitivity, NLR, and NPV with a cutoff value of OCST-ODI 5/h were 96.4%, 0.068, and 91.9% to detect PSG-AHI <20/h and 84.1%, 0.21, and 45.9% to detect PSG-AHI <5/h. or definitive diagnosis in children, the corresponding values with a cutoff value of OCST-ODI 25/h were 98.6%, 16.0, and 90.9% to detect PSG-AHI ≥10/h and 98.1%, 8.281, and 90.9% for PSG-AHI ≥5/h. For exclusive diagnosis in children, with a cutoff of OCST-ODI 10/h, the corresponding values were 62.2%, 0.446, and 78.2% to detect PSG-AHI <10/h, 45.3%, 0.674, and 55.1% for PSG-AHI <5/h, and 34.0%, 0.908, and 10.3% for PSG-AHI <1/h. Statistical data of preschool children tended to be worse than those of school age children. ConclusionsIn adults, OCST is reliable for the definitive diagnosis of AHI ≥20/h or ≥5/h and the exclusive diagnosis of AHI <20/h. However, in children, OCST should not be used alone for the definitive diagnosis or exclusive diagnosis.

Making the Most of Simplified Sleep Apnea Testing.

Evidence has been lacking to compare the performance of laboratory-based and home-based testing for obstructive sleep apnea (OSA) in patients with low pretest probability for it or in selecting the...

Exploiting temporal and nonstationary features in breathing sound analysis for multiple obstructive sleep apnea severity classification

BackgroundPolysomnography (PSG) is the gold standard test for obstructive sleep apnea (OSA), but it incurs high costs, requires inconvenient measurements, and is limited by a one-night test. Thus, a repetitive OSA screening test using affordable data would be effective both for patients interested in their own OSA risk and in-hospital PSG. The purpose of this research was to develop a four-OSA severity classification model using a patient’s breathing sounds.MethodsBreathing sounds were recorded from 83 subjects during a PSG test. There was no exclusive experimental protocol or additional recording instruments use throughout the sound recording procedure. Based on the Apnea-Hypopnea Index (AHI), which indicates the severity of sleep apnea, the subjects’ sound data were divided into four-OSA severity classes. From the individual sound data, we proposed two novel methods which were not attempted in previous OSA severity classification studies. First, the total transition probability of approximated sound energy in time series, and second, the statistical properties derived from the dimension-reduced cyclic spectral density. In addition, feature selection was conducted to achieve better results with a more relevant subset of features. Then, the classification model was trained using support vector machines and evaluated using leave-one-out cross-validation.ResultsThe overall results show that our classification model is better than existing multiple OSA severity classification method using breathing sounds. The proposed method demonstrated 79.52% accuracy for the four-class classification task. Additionally, it demonstrated 98.0% sensitivity, 75.0% specificity, and 92.78% accuracy for OSA subject detection classification with AHI threshold 5.ConclusionsThe results show that our proposed method can be used as part of an OSA screening test, which can provide the subject with detailed OSA severity results from only breathing sounds.

Agreement Between Results of Home Sleep Testing for Obstructive Sleep Apnea with and Without a Sleep Specialist

BackgroundObstructive sleep apnea is a prevalent yet underdiagnosed condition associated with cardiovascular morbidity and mortality. Home sleep testing offers an efficient means for diagnosing obstructive sleep apnea but has been deployed primarily in clinical samples with a high pretest probability. The present study sought to assess whether obstructive sleep apnea can be diagnosed with home sleep testing in a nonreferred sample without involvement of a sleep medicine specialist. MethodsA study of community-based adults with untreated obstructive sleep apnea was undertaken. Misclassification of disease severity according to home sleep testing with and without involvement of a sleep medicine specialist was assessed, and agreement was characterized using scatter plots, Pearson's correlation coefficient, Bland-Altman analysis, and the κ statistic. Analyses were also conducted to assess whether any observed differences varied as a function of pretest probability of obstructive sleep apnea or subjective sleepiness. ResultsThe sample consisted of 191 subjects, with more than half (56.5%) having obstructive sleep apnea. Without involvement of a sleep medicine specialist, obstructive sleep apnea was not identified in only 5.8% of the sample. Analyses comparing the categorical assessment of disease severity with and without a sleep medicine specialist showed that in total, 32 subjects (16.8%) were misclassified. Agreement in the disease severity with and without a sleep medicine specialist was not influenced by the pretest probability or daytime sleep tendency. ConclusionObstructive sleep apnea can be reliably identified with home sleep testing in a nonreferred sample, irrespective of the pretest probability of the disease.

Home Sleep Tests for Obstructive Sleep Apnea (OSA)

Obstructive sleep apnea (OSA) is a fairly common condition that, if left untreated, can lead to complications such as high blood pressure and heart disease. Polysomnography (PSG) is the most accurate method for diagnosing OSA, but it is a cumbersome and expensive test. A well-validated, easier to perform and less expensive alternative is the home sleep test (HST). The purpose of this review is to educate the primary care provider about the important differences between PSG and HSTs, the advantages and limitations of both modalities, identifying patients who are appropriate candidates for the HST, identifying patients in whom the HST should not be performed, and further evaluation of patients who have a negative HST.