In-laboratory Polysomnography Research Articles

Sleep, Sleep Apnea, and Fatigue in People Living With HIV

Background: People living with HIV (PLWH) often report fatigue even when viral load is suppressed. Obstructive sleep apnea (OSA), which is often associated with fatigue, is common in PLWH, but whether OSA explains fatigue in this population is unknown. Setting: Academic university-affiliated HIV and Sleep Medicine Clinics. Methods: PLWH, aged 18–65 years, with a body mass index of 20–35 kg/m2 and viral suppression (RNA <200 copies per mL), were recruited to undergo daytime questionnaires, including the Functional Assessment of Chronic Illness Therapy Fatigue Scale and Epworth Sleepiness Scale, 7 days of actigraphy (to determine daily sleep duration and activity amplitude and rhythms), and an in-laboratory polysomnography to assess for the presence and severity of OSA. Results: Of 120 subjects with evaluable data, 90 (75%) had OSA using the American Academy of Sleep Medicine 3% desaturation or arousal criteria, with an apnea–hypopnea index >5/h. There was no difference in Functional Assessment of Chronic Illness Therapy scores between those with and without OSA, although those with OSA did report more daytime sleepiness as measured using the Epworth Sleepiness Scale. In a multivariable model, predictors of fatigue included more variable daily sleep durations and decreased mean activity counts. Sleepiness was predicted by the presence of OSA. Conclusion: OSA was very common in our cohort of PLWH, with those with OSA reporting more sleepiness but not more fatigue. Variability in sleep duration was associated with increased fatigue. Further study is needed to determine if treatment of OSA, or an emphasis on sleep consistency and timing, improves symptoms of fatigue in PLWH.

Prospective crossover trial of positional and CPAP therapy for the treatment of mild-to-moderate positional obstructive sleep apnea.

To evaluate efficacy of vibrotactile positional therapy (PT) compared to standard CPAP therapy in mild-to-moderate positional obstructive sleep apnea (pOSA). Prospective crossover randomized controlled trial of adult patients with treatment-naïve, symptomatic, mild-to-moderate pOSA - defined as ≥5 total apnea-hypopnea index (AHI) <30 with supine-to-non-supine (s:ns)AHI ratio ≥2. Participants were randomized to in-laboratory treatment initiation polysomnography with either PT or CPAP on sequential nights before an eight-week trial of each therapy. The primary endpoint was symptomatic improvement (Epworth Sleepiness Scale; ΔESS). Secondary endpoints included patient preference, usage, sleep architecture and quality of life (QoL) measures. 52 participants were enrolled and completed both arms of the study. Participants were symptomatic with median ESS 12 (IQR 10-14). Treatment resulted in a significant (p<0.001) symptomatic improvement with both PT and CPAP (ΔESS 4; IQR 6-11) without a significant difference between treatment arms (p=0.782). PT was effective at restricting supine sleep and demonstrated improved sleep efficiency compared with CPAP, although no better than baseline. Both therapies were effective at reducing AHI, although CPAP demonstrated superior AHI reduction. There were otherwise no clinically significant differences in sleep architecture, usage, or secondary outcomes including overall patient preference. In this cohort, treatment with PT or CPAP resulted in clinically significant symptomatic improvement (ΔESS) that was not significantly different between treatment arms. No real difference was seen in other secondary outcome measures. This study provides further evidence to support the use of PT as an alternative first-line therapy with CPAP in appropriately selected patients with pOSA. Registry: Australian New Zealand Clinic Trials Registry; Name: Prospective crossover trial of Positional and Continuous positive airway pressure Therapy for the treatment of mild-to-moderate positional obstructive sleep apnoea; Identifier: ACTRN12619000475145; URL: https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377221&isReview=true.

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

Hypoglossal nerve stimulation (HGNS) is an implantable therapy for obstructive sleep apnea (OSA). Therapy efficacy is currently confirmed by a formal sleep study after empiric adjustment by the patient at home based on their subjective experience with the device. Home-based longitudinal apnea hypopnea index (AHI) measurements have the potential to refine HGNS therapeutic amplitude selection with objective data. Our objective was to compare AHI derived from routine sleep studies and two different home sleep devices in new HGNS recipients. Prospectively enrolled patients receiving HGNS therapy were provided a Sleep Tracking Mat (Withings, Issy-les-Moulineaux, France) and NightOwl peripheral arterial tonometry (PAT) sensor (Ectosense, Leuven, Belgium) for longitudinal, home AHI monitoring from 1 to 6 months post-implant. Therapy efficacy was assessed at 3 and 6 months post-implant using in-lab polysomnography (PSG) or home sleep apnea test (HSAT). The sleep mat and PAT sensor AHI were compared against PSG and HSAT for accuracy of OSA severity identification. Sixty patients were enrolled across 5 centers and followed for 6 months. The sleep mat had sensitivity and specificity for identifying AHI <15 of 61% and 82% and AHI <30 of 77% and 100%. The PAT device had sensitivity and specificity for identifying AHI <15 of 57% and 77% and AHI <30 of 81% and 80%. The sleep mat and PAT sensor demonstrated high sensitivity and specificity for detection of mild and moderate OSA in patients with HGNS therapy and may enable longitudinal objective monitoring of HGNS efficacy in the home setting. 3 Laryngoscope, 2024.

Sex-specific Age-Related Worsening of Pathological Endotypic Traits in Patients with Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) is more prevalent in men and older adults. Few studies have explored variations in pathological endotypic traits by age and sex using a large patient sample, offering insights into the development of the disease. Our study aims to examine how endotype characteristics of obstructive sleep apnea vary across age in different sex. A cross-sectional study was conducted, enrolling 2296 adult patients referred for in-laboratory diagnostic polysomnography at a single sleep center in Taiwan. Among them, 1374 had an apnea-hypopnea index ≥ 5. Using the "Phenotyping Using Polysomnography" method, we estimated four endotypic traits-arousal threshold, upper airway collapsibility, loop gain, and upper airway muscle compensation. Demographic and polysomnographic characteristics were compared between sexes and age groups. Generalized linear regression and generalized additive models were employed to explore the associations of sex and age with endotypic traits. Men with OSA exhibited higher collapsibility and lower compensation than women (difference: 4.32 %eupnea and 4.49 %eupnea, respectively). Younger patients with OSA had a higher prevalence of obesity, more snoring symptoms, and lower loop gain compared to older patients. For men, age was correlated with increased collapsibility, increased loop gain, and decreased arousal threshold after 37 years old. Whereas in women, endotypic traits were not associated with age, except for an increase in loop gain with advancing age. Personalized treatment options for OSA should take into consideration age and sex. Reducing loop gain could be a treatment objective for older patients with OSA.

Sleep-disordered breathing diagnosis: a comprehensive audit of home sleep testing in real clinical settings.

This study aimed to investigate the indications and outcomes of Home Sleep Testing (HST) for patients with suspected obstructive sleep apnea (OSA), aligning with guidelines set forth by the American Academy of Sleep Medicine and the European Sleep Research Society. Specifically, we aimed to audit whether validated type 3 polygraphy could effectively ensure patient care while optimizing resource utilization. A retrospective analysis was conducted on data from patients undergoing type 3 polygraphy for suspected OSA in a tertiary referral hospital between January 2022 and December 2022. Demographic, clinical, and management data were collected. The efficacy of HST in guiding management plans was evaluated, with outcomes categorized as effective or ineffective based on subsequent need for in-laboratory polysomnography. While 85% of patients received a reliable diagnosis, 44.4% of them still required subsequent polysomnography, primarily due to adherence to funding regulations, rather than clinical need for further testing. Factors impacting the efficacy of HST included patient age, severity of apnea, and referral by a certified sleep specialist physician. Our study highlighted the potential of type 3 polygraphy, as a valuable tool for diagnosing OSA in an outpatient setting. However, having the result interpreted by a certified sleep specialist doctor was not enough. To streamline the care pathway, the referral for polygraphy had also to be made by a trained specialist. Challenges related to funding regulations, patient demographics and physician training stress the need for optimized diagnostic pathways to improve patient care and resource utilization.

Feasibility and usability of three consecutive nights with self-applied, home polysomnography.

In-laboratory polysomnography, the gold-standard for diagnosing sleep disorders, is resource-demanding and not conducive to multiple night evaluations. Ambulatory polysomnography, especially when self-applied, could be a viable alternative. This study aimed to assess the feasibility and reliability of self-applied polysomnography over three consecutive nights in untrained participants, assessing: technical success rate; comparing sleep diagnostic variables from single and multiple nights; and evaluating participants' subjective experience. Data were collected from 78 participants (55.1% females) invited to test a self-applicable polysomnography device for three consecutive nights at home. The technical success rate for valid sleep recordings was 82.5% out of 234 planned study nights, with 87.2% of participants obtaining at least two valid nights. Misclassification of obstructive sleep apnea severity was higher in participants with mild OSA (21.4%) compared with those with moderate-to-severe obstructive sleep apnea or no obstructive sleep apnea. Sleep efficiency and wake after sleep onset showed improvement from Night 1 to Night 3 (p < 0.001), and the mean polysomnography set-up time decreased significantly over this period. Participants reported moderate-to-high satisfaction with the device (System Usability Scale score 71.2 ± 12.4). The findings suggest that self-applied polysomnography is a feasible diagnostic method for untrained individuals at risk for sleep disorders, and that multiple night assessments can improve diagnostic precision for mild obstructive sleep apnea cases.

Amyloid profile is associated with sleep quality in preclinical but not in prodromal Alzheimer’s disease older adults

BackgroundFew studies have assessed whether neuropathological markers of AD in the preclinical and prodromal stages are associated with polysomnographic changes and obstructive sleep apnea (OSA). MethodsThis was a cross-sectional, case-control study of older adults (≥60 years) without relevant clinical and psychiatric comorbidities selected randomly from a cohort of individuals without dementia in a tertiary university hospital in São Paulo, Brazil. They underwent neuropsychological evaluation for clinical diagnosis and were allocated into two samples: cognitively unimpaired (CU) and mild cognitive impairment (MCI). Also, they underwent PET-PiB to determine the amyloid profile and all-night in-lab polysomnography. For each sample, we compared polysomnographic parameters according to the amyloid profile (A+ vs A-). ResultsWe allocated 67 participants (mean age 73 years, SD 10,1), 70 % females, 14 ± 5 years of education, into two samples: CU (n = 28, 42.4 %) and MCI (n = 39, 57.6 %). In the CU sample, the group A+ (n = 9) showed worse sleep parameters than A- (n = 19) (lower total sleep time (p = 0.007), and sleep efficiency (p = 0.005); higher sleep onset latency (p = 0.025), wake time after sleep onset (p = 0.011), and arousal index (AI) (p = 0.007)), and changes in sleep structure: higher %N1 (p = 0.005), and lower %REM (p = 0.006). In the MCI sample, MCI A-had higher AI (p = 0.013), respiratory disturbance index (p = 0.025, controlled for age), and higher rates of severe OSA than A+. DiscussionThe amyloid profile was associated with polysomnographic markers of worse sleep quality in individuals with preclinical AD but not with prodromal AD, probably due to the higher frequencies of severe OSA.

The Correlation of Computerized Scoring in Home Sleep Apnea Tests with Technician Visual Scoring for Assessing the Severity of Obstructive Sleep Apnea.

Background: Obstructive sleep apnea (OSA) affects a significant proportion of the global population, with many having moderate or severe forms of the disease. Home Sleep Apnea Testing (HSAT) has become the most common method of diagnosing OSA, replacing in-lab polysomnography. Polysmith software Version 11 by Nihon Kohden allows for the automatic scoring of respiratory events. This study aimed to assess the validity of this technology. Study Objectives: The objective was to assess the accuracy of the Polysmith Software Automatic Scoring Algorithm of HSATs in comparison to that of sleep technicians. Methods: One hundred twenty HSATs were scored by both sleep technicians and Polysmith software. The measured values were the respiratory event index (REI), apneic events, and hypopneic events. Agreement between the two methods was reached by utilizing the Kruskal-Wallis test, Pearson correlation coefficient, and Bland-Altman plot, as well as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: The correlation between the REI calculated by the software and technicians proved to be strong overall (r = 0.96, p < 0.0001). The mild OSA group had a moderate correlation (r = 0.45, p = 0.0129). The primary snoring, moderate OSA, and severe OSA groups showed stronger correlations (r = 0.69, p < 0.0001; r = 0.56, p = 0.012; r = 0.71, p < 0.0001). The analysis conducted across all groups demonstrated an average sensitivity of 81%, specificity of 94%, PPV of 82%, and NPV of 94%, with an overall accuracy of 81%. When combining the moderate and severe OSA groups into a single category, the sensitivity was 90%, specificity was 100%, PPV was 100%, and NPV was 91%. Conclusions: OSA can be reliably diagnosed from HSATs with the automated Polysmith software across all OSA disease severity groups, with higher levels of accuracy in moderate/severe OSA and lower levels of accuracy in mild OSA.

Sleep architecture in idiopathic hypersomnia: the influence of age, sex, and body mass index

This study aimed to progress the understanding of idiopathic hypersomnia (IH) by assessing the moderating influence of individual characteristics, such as age, sex, and body mass index (BMI) on sleep architecture. In this retrospective study, 76 IH participants (38.1 ± 11.3 years; 40 women) underwent a clinical interview, an in-laboratory polysomnography with a maximal 9-h time in bed and a multiple sleep latency test (MSLT). They were compared to 106 healthy controls (38.1 ± 14.1 years; 60 women). Multiple regressions were used to assess moderating influence of age, sex, and BMI on sleep variables. We used correlations to assess whether sleep variables were associated with Epworth Sleepiness Scale scores and mean sleep onset latency on the MSLT in IH participants. Compared to controls, IH participants had shorter sleep latency (p = 0.002), longer total sleep time (p < 0.001), more time spent in N2 sleep (p = 0.008), and showed trends for a higher sleep efficiency (p = 0.023) and more time spent in rapid eye movement (REM) sleep (p = 0.022). No significant moderating influence of age, sex, or BMI was found. More severe self-reported sleepiness in IH patients was correlated with shorter REM sleep latency and less N1 sleep in terms of proportion and duration (ps < 0.01). This study shows that, when compared to healthy controls, patients with IH had no anomalies in their sleep architecture that can explain their excessive daytime sleepiness. Moreover, there is no moderating influence of age, sex, and BMI, suggesting that the absence of major group differences is relatively robust.

Association between sleep microarchitecture and cognition in obstructive sleep apnea

Abstract Study Objectives Obstructive sleep apnea (OSA) increases the risk of cognitive impairment. Measures of sleep microarchitecture from EEG may help identify patients at risk of this complication. Methods Participants with suspected OSA (n = 1142) underwent in-laboratory polysomnography and completed sleep and medical history questionnaires, and tests of global cognition (Montreal Cognitive Assessment, MoCA), memory (Rey Auditory Verbal Learning Test, RAVLT) and information processing speed (Digit–Symbol Coding, DSC). Associations between cognitive scores and stage 2 non-rapid eye movement (NREM) sleep spindle density, power, frequency and %-fast (12–16Hz), odds-ratio product (ORP), normalized EEG power (EEGNP), and the delta:alpha ratio were assessed using multivariable linear regression (MLR) adjusted for age, sex, education, and total sleep time. Mediation analyses were performed to determine if sleep microarchitecture indices mediate the negative effect of OSA on cognition. Results All spindle characteristics were lower in participants with moderate and severe OSA (p ≤ .001, vs. no/mild OSA) and positively associated with MoCA, RAVLT, and DSC scores (false discovery rate corrected p-value, q ≤ 0.026), except spindle power which was not associated with RAVLT (q = 0.185). ORP during NREM sleep (ORPNREM) was highest in severe OSA participants (p ≤ .001) but neither ORPNREM (q ≥ 0.230) nor the delta:alpha ratio were associated with cognitive scores in MLR analyses (q ≥ 0.166). In mediation analyses, spindle density and EEGNP (p ≥ .048) mediated moderate-to-severe OSA’s negative effect on MoCA scores while ORPNREM, spindle power, and %-fast spindles mediated OSA’s negative effect on DSC scores (p ≤ .018). Conclusions Altered spindle activity, ORP and normalized EEG power may be important contributors to cognitive deficits in patients with OSA.

Connecting the dots: analysing the relationship between AHI and ODI in obstructive sleep apnea

BackgroundIn the lab type-1 Polysomnography (PSG) is the gold standard for the diagnosis of Obstructive sleep apnea (OSA). But in view, the increasing prevalence, highly expensive, and the presence of a pandemic state make it sometimes impractical to perform PSG in all patients suspected of OSA. The objective of our study was to compare the correlation between the gold standard Autoscored Apnea Hypopnea Index (AHI) and Oxygen desaturation index (ODI) based classification of the severity of OSA.MethodologyIt was a single-centered hospital-based cross-sectional study in which a total of 176 Subjects suspected of OSA were recruited and underwent overnight 7 channels of in-lab polysomnography at AIIMS Patna. Demographic details, comorbidities, and lab data were collected for all enrolled patients. BMI, STOP-BANG score, and Epworth sleepiness score (ESS) were also calculated for all subjects. They were categorized into mild, moderate, and severe OSA based on AHI and ODI values of 5–14.9, 15–29.9, and ≥ 30 events per hour, respectively.Recordings of polysomnography (PSG) were presented with descriptive statistics. Data is presented as the “mean ± standard deviations” for continuous variables and percentage frequencies for categorical variables. The Chi-square test was used to compare the discrete variables. Statistical significance was set at an alpha level of 0.05 with P < 0.05, with a two-tailed probability. Spearman's rank correlation analysis was used to test the strength and direction of the association between OSA severity (using AHI classification) and the Oxygen Desaturation Index.ResultsThe Mean (SD) age of patients enrolled in our study was 47.42(12.60) years with 57.95% males. Among comorbidities, 31.8% (n = 56) were known cases or incidentally diagnosed with Diabetes Mellitus Type 2, 43.18% (n = 76) were hypertensive and 31.8% (n = 56) had hypothyroidism. The mean HbA1c level among Diabetic patients was 6.05 (1.27) and the mean TSH level among Hypothyroidism patients was 12.24 (27.34). There was a positive correlation between AHI and ODI in our study (Pearson’s correlation coefficient = 0.897).ConclusionGood concordance between AHI and ODI makes nocturnal oximetry a less expensive tool to confidently screen patients with severe OSA. This may be applicable in smaller centers where facilities and expertise for a full night PSG may not be easily available.

The stability of slow-wave sleep and EEG oscillations across two consecutive nights of laboratory polysomnography in cognitively normal older adults.

Laboratory polysomnography provides gold-standard measures of sleep physiology, but multi-night investigations are resource intensive. We assessed the night-to-night stability via reproducibility metrics for sleep macrostructure and electroencephalography oscillations in a group of cognitively normal adults attending two consecutive polysomnographies. Electroencephalographies were analysed using an automatic algorithm for detection of slow-wave activity, spindle and K-complex densities. Average differences between nights for sleep macrostructure, electroencephalography oscillations and sleep apnea severity were assessed, and test-retest reliability was determined using two-way intraclass correlations. Agreement was calculated using the smallest real differences between nights for all measures. Night 2 polysomnographies showed significantly greater time in bed, total sleep time (6.3 hr versus 6.8 hr, p < 0.001) and percentage of rapid eye movement sleep (17.5 versus 19.7, p < 0.001). Intraclass correlations were low for total sleep time, percentage of rapid eye movement sleep and sleep efficiency, moderate for percentage of slow-wave sleep and percentage of non-rapid eye movement 2 sleep, good for slow-wave activity and K-complex densities, and excellent for spindles and apnea-hypopnea index with hypopneas defined according to 4% oxygen desaturation criteria only. The smallest real difference values were proportionally high for most sleep macrostructure measures, indicating moderate agreement, and proportionally lower for most electroencephalography microstructure variables. Slow waves, K-complexes, spindles and apnea severity indices are highly reproducible across two consecutive nights of polysomnography. In contrast, sleep macrostructure measures all demonstrated poor reproducibility as indicated by low intraclass correlation values and moderate agreement. Although there were average differences in percentage of rapid eye movement sleep and total sleep time, these were numerically small and perhaps functionally or clinically less significant. One night of in-laboratory polysomnography is enough to provide stable, reproducible estimates of an individual's sleep concerning measures of slow-wave activity, spindles, K-complex densities and apnea severity.

Posttraumatic Stress Disorder and Obstructive Sleep Apnea in Twins

Obstructive sleep apnea (OSA) is a common condition in older adult (aged >65 years) populations, but more mechanistic research is needed to individualize treatments. Previous evidence has suggested an association between OSA and posttraumatic stress disorder (PTSD) but is limited by possible selection bias. High-quality research on this association with a careful evaluation of possible confounders may yield important mechanistic insight into both conditions and improve treatment efforts. To investigate the association of current PTSD symptoms and PTSD diagnosis with OSA. This cross-sectional study of twin pairs discordant for PTSD, which allows for adjustment for familial factors, was conducted using in-laboratory polysomnography from March 20, 2017, to June 3, 2019. The study sample comprised male veteran twins recruited from the Vietnam Era Twin Registry. The data analysis was performed between June 11, 2022, and January 30, 2023. Symptoms of PTSD in twins who served in the Vietnam War. Diagnosis of PTSD was a secondary exposure. Obstructive sleep apnea was assessed using the apnea-hypopnea index (AHI) (≥4% oxygen saturation criterion as measured by events per hour) with overnight polysomnography. Symptoms of PTSD were assessed using the PTSD Checklist (PCL) and structured clinical interview for PTSD diagnosis. A total of 181 male twins (mean [SD] age, 68.4 [2.0] years) including 66 pairs discordant for PTSD symptoms and 15 pairs discordant for a current PTSD diagnosis were evaluated. In models examining the PCL and OSA within pairs and adjusted for body mass index (BMI) and other sociodemographic, cardiovascular, and psychiatric risk factors (including depression), each 15-point increase in PCL was associated with a 4.6 (95% CI, 0.1-9.1) events-per-hour higher AHI. Current PTSD diagnosis was associated with an adjusted 10.5 (95% CI, 5.7-15.3) events-per-hour higher AHI per sleep-hour. Comparable standardized estimates of the association of PTSD symptoms and BMI with AHI per SD increase (1.9 events per hour; 95% CI, 0.5-3.3 events per hour) were found. This cross-sectional study found an association between PTSD and sleep-disordered breathing. The findings have important public health implications and may also enhance understanding of the many factors that potentially affect OSA pathophysiology.

Comparison of sleep position monitoring between NaTu sensor and video-validated polysomnography in patients with obstructive sleep apnea.

This study aimed to evaluate the accuracy of a Bluetooth position monitor called NaTu sensor and its mobile phone application for detecting sleep position among patients with obstructive sleep apnea (OSA) during polysomnography (PSG). A cross-sectional study was conducted on adults with suspected of having OSA who underwent PSG. Sleep positions were recorded simultaneously using a video-validated PSG position sensor and the NaTu sensor. The area under the Receiver Operator Characteristic curve (ROC AUC), sensitivity, and specificity values were calculated to evaluate the validity of the NaTu sensor. Ninety participants (56.7% male) were included, with median age of 40.0years and body mass index of 29.4kg/m2. The mean AHI was 58.4 ± 31.2 events/hour, categorizing the severity of OSA as mild (5.6%), moderate (18.9%), and severe (75.5%). Sleep positions (supine, lateral right, lateral left) identified by the NaTu sensor closely agreed with the video-validated PSG. The kappa statistic demonstrated almost perfect agreement (k = 0.95, P < 0.001) for overall position recording. The ROC AUC for identifying supine, lateral right, and lateral left positions ranged from 0.974 to 0.981, with sensitivity ranging from 95.1% to 99.1% and specificity from 96.5% to 99.6%. Our wearable sensor monitoring significantly agrees with video-validated PSG in identifying sleep positions. This device is reliable and accurate for position monitoring and could be an alternative tool for monitoring positions in in-lab PSG, home sleep apnea testing, or tracking positional treatment at home. Thaiclinicaltrials.org with number TCTR20210701008.

Hypoglossal Nerve Stimulation Therapy in a Belgian Cohort of Obstructive Sleep Apnea Patients.

Hypoglossal nerve stimulation (HGNS) has emerged as a widespread and innovative treatment option for selected moderate-to-severe obstructive sleep apnea (OSA) patients who cannot be treated effectively with traditional treatment modalities. In this observational cohort study, the objective and subjective outcomes of Belgian OSA patients treated with HGNS therapy were analyzed at 6 and 12 months post-implantation. Thirty-nine patients implanted with a respiration-synchronized HGNS device at the Antwerp University Hospital w ere included in this study. Patients underwent baseline in-laboratory polysomnography and a follow-up sleep study 6 and 12 months post-implantation. Questionnaires on patient experience and daytime sleepiness were filled out and data on objective therapy usage were collected. All 39 patients completed the 6-month follow-up and 21 patients (54%) completed the 12-month follow-up. Median AHI decreased from 33.8 [26.1;45.0] to 10.2 [4.8;16.4] at the 6-month follow-up, and to 9.6 [4.1;16.4] at the 12-month follow-up (p < 0.001). The surgical success rate, according to the Sher20 criteria, was 80% and 76% at the 6- and 12-month follow-ups, respectively. Median ESS improved from 12.0 [7.0;18.0] at baseline to 6.0 [2.5;11.0] at 6 months (p < 0.001) and to 6.5 [2.8;11.5] at 12 months (p = 0.012). Objective therapy usage was 7.4 [6.6;8.0] and 7.0 [5.9:8.2] h/night at the 6- and 12-month follow-ups, respectively. A high overall clinical effectiveness of HGNS therapy, as shown by a mean disease alleviation of 58%, was demonstrated at 12 months post-implantation. Overall, HGNS therapy using respiration-synchronized neurostimulation of the XII cranial nerve resulted in a significant improvement in both objective and subjective OSA outcomes, with a high level of patient satisfaction and high treatment adherence.

Screening and risk assessment for sleep-related breathing disorders in individuals living with spinal cord injury

ObjectivesThis research work was performed: (1) To assess the accessibility of in-laboratory polysomnography for individuals with spinal cord injury (SCI); (2) to evaluate the validity of four screening questionnaires for sleep-related breathing disorders (SRBDs); and (3) to assess the association between anthropometric features and apnea-hypopnea index (AHI). MethodsAn Environmental scan (E-scan) was performed in the province of Ontario, where all sleep clinics were invited to complete the E-scan survey. Furthermore, a cross-sectional study was performed at a rehabilitation hospital (Canada), where consecutive adults with subacute/chronic (>1 month) SCI were recruited. Using a home-based screening sleep test (HBSST), the validity of the Berlin, STOP, Medical Outcomes Study Sleep Scale [MOS-SS], and STOP-Bang screening questionnaires was assessed. The association between AHI and three features (i.e., neck circumference, body mass index [BMI] and oropharynx opening as assessed using the Modified Mallampati classification [MMC]) was evaluated. ResultsAccording to the E-scan, access to polysomnography is limited for the SCI population in Ontario. Of the 28 participants with SCI (11 females, 17 males; mean age: 54.9 years) included in the cross-sectional study, 32.1 % were diagnosed with moderate-to-severe SRBD. The performance of the questionnaires was considered insufficient for screening of individuals living with SCI. AHI was not associated with neck circumference, BMI, or MMC. ConclusionsThose results suggest that the use of a HBSST could overcome the barriers for individuals with SCI to access diagnostic testing of SRBDs. The use of screening questionnaires and risk assessment for SRBDs in the SCI population is unreliable.

A Comparison of a Wrist-Worn Portable Device (WatchPAT 200)™ with In-Lab Polysomnography for the Diagnosis of Obstructive Sleep Apnea

A Comparison of a Wrist-Worn Portable Device (WatchPAT 200)™ with In-Lab Polysomnography for the Diagnosis of Obstructive Sleep Apnea

In-Laboratory Polysomnography Worsens Obstructive Sleep Apnea by Changing Body Position Compared to Home Testing.

(1) Background: Home sleep apnea testing, known as polysomnography type 3 (PSG3), underestimates respiratory events in comparison with in-laboratory polysomnography type 1 (PSG1). Without head electrodes for scoring sleep and arousal, in a home environment, patients feel unfettered and move their bodies more naturally. Adopting a natural position may decrease obstructive sleep apnea (OSA) severity in PSG3, independently of missing hypopneas associated with arousals. (2) Methods: Patients with suspected OSA performed PSG1 and PSG3 in a randomized sequence. We performed an additional analysis, called reduced polysomnography, in which we blindly reassessed all PSG1 tests to remove electroencephalographic electrodes, electrooculogram, and surface electromyography data to estimate the impact of not scoring sleep and arousal-based hypopneas on the test results. A difference of 15 or more in the apnea-hypopnea index (AHI) between tests was deemed clinically relevant. We compared the group of patients with and without clinically relevant differences between lab and home tests (3) Results: As expected, by not scoring sleep, there was a decrease in OSA severity in the lab test, similar to the home test results. The group of patients with clinically relevant differences between lab and home tests presented more severe OSA in the lab compared to the other group (mean AHI, 42.5 vs. 20.2 events/h, p = 0.002), and this difference disappeared in the home test. There was no difference between groups in the shift of OSA severity by abolishing sleep scoring in the lab. However, by comparing lab and home tests, there were greater variations in supine AHI and time spent in the supine position in the group with a clinically relevant difference, either with or without scoring sleep, showing an impact of the site of the test on body position during sleep. These variations presented as a marked increase or decrease in supine outcomes according to the site of the test, with no particular trend. (4) Conclusions: In-lab polysomnography may artificially increase OSA severity in a subset of patients by inducing marked changes in body position compared to home tests. The location of the sleep test seems to interfere with the evaluation of patients with more severe OSA.

Effect of obesity on sleep apnea pathogenesis differs in women versus men: multiple mediation analyses in the retrospective SNOOzzzE cohort.

There are multiple mechanisms underlying obstructive sleep apnea (OSA) development. However, how classic OSA risk factors such as body mass index (BMI) and sex portend to OSA development has not been fully described. Thus we sought to evaluate how obesity leads to OSA and assess how these mechanisms differ between men and women. The San Diego Multi-Outcome OSA Endophenotype (SNOOzzzE) cohort includes 3,319 consecutive adults who underwent a clinical in-laboratory polysomnography at the University of California, San Diego, sleep clinic between January 2017 and December 2019. Using routine polysomnography signals, we determined OSA endotypes. We then performed mediation analyses stratified by sex to determine how BMI influenced the apnea-hypopnea index (AHI) using OSA pathophysiological traits as mediators, adjusting for age, race, and ethnicity. We included 2,146 patients of whom 919 (43%) were women and 1,227 (57%) were obese [body mass index (BMI) > 30 kg/m2]. BMI was significantly associated with AHI in both women and men. In men, the adjusted effect of BMI on AHI was partially mediated by a reduction in upper airway stiffness (βstandardized = 0.124), a reduction in circulatory delay (βstandardized = 0.063), and an increase in arousal threshold (βstandardized = 0.029; Pboot-strapped,all < 0.05). In women, the adjusted effect of BMI on AHI was partially mediated by a reduction in upper airway stiffness (βstandardized = 0.05) and circulatory delay (βstandardized = 0.037; Pboot-strapped,all < 0.05). BMI-related OSA pathogenesis differs by sex. An increase in upper airway collapsibility is consistent with prior studies. A reduction in circulatory delay may lead to shorter and thus more events per hour (higher AHI), while the relationship between arousal threshold and OSA is likely complex.NEW & NOTEWORTHY Our data provide important insights into obesity-related obstructive sleep apnea (OSA) pathogenesis, thereby validating, and extending, prior research findings. This is the largest sample size study to examine the relationships between obesity and gender on OSA pathogenesis. The influence of obesity on sleep apnea severity is mediated by different mechanistic traits (endotypes).

Performance of a commercial smart watch compared to polysomnography reference for overnight continuous oximetry measurement and sleep apnea evaluation.

We evaluated the accuracy and precision of continuous overnight oxygen saturation (SpO2) measurement by a commercial wrist device (WD) incorporating high-grade sensors and investigated WD estimation of sleep-disordered breathing by quantifying overnight oxygen desaturation index compared to polysomnography (PSG) oxygen desaturation index and apnea-hypopnea index (AHI) with and without sleep questionnaire data to assess the WD's ability to detect obstructive sleep apnea and determine its severity. Participants completed sleep questionnaires, had a WD (Samsung Galaxy Watch 4) placed on their wrist, and underwent attended, in-laboratory overnight PSG (Nihon Kohden) with a pulse oximetry probe secured either to a finger or an ear lobe. PSG data were scored by a single experienced registered PSG technologist. Statistical analysis included demographic characteristics, continuous SpO2 measurement WD vs PSG root-mean-square error with Bland-Altman plot and linear regression associations. Predictive models for PSG oxygen desaturation index and AHI severity were built using logistic regression with probability cutoffs determined via receiver operating curve characteristics. The 51 participants analyzed had a median age of 49 (range, 22-78) years; 66.7% were male, with median body mass index of 28.1 (range, 20.1-47.3) kg/m2 with a race/ethnicity distribution of 49.0% Caucasian, 25.5% Hispanic, 9.8% African American, 9.8% Asian, and 5.9% Middle Eastern. WD vs PSG continuous SpO2 measurement in percentage points demonstrated a bias of 0.91 (95% confidence interval, 0.38, 1.45), standard deviation of 2.37 (95% confidence interval, 2.36, 2.38), and root-mean-square error of 2.54 (95% confidence interval, 2.34, 2.73). WD area under the curve receiver operating curve characteristics for predicting PSG were 0.882 oxygen desaturation index > 15 events/h, 0.894 AHI > 30 events/h, 0.800 AHI > 15 events/h, and 0.803 AHI > 5 events/h. WD plus select sleep questionnaire areas under the curve for predicting PSG were 0.943 AHI > 30 events/h, 0.868 AHI > 15 events/h, and 0.863 AHI > 5 events/h. The WD conducted reliable overnight continuous SpO2 monitoring with root-mean-square error < 3% vs PSG. Predictive models of PSG AHI based on WD measurements alone, or plus sleep questionnaires, demonstrated excellent to outstanding discrimination for obstructive sleep apnea identification and severity. Longitudinal WD use should be evaluated promptly based on the WD's potential to improve accessibility and accuracy of obstructive sleep apnea testing, as well as support treatment follow-up. Browne SH, Vaida F, Umlauf A, Kim J, DeYoung P, Owens RL. Performance of a commercial smart watch compared to polysomnography reference for overnight continuous oximetry measurement and sleep apnea evaluation. J Clin Sleep Med. 2024;20(9):1479-1488.