Single Sleep Center Research Articles

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.

Relationship between Symptom Profiles and Endotypes among Patients with Obstructive Sleep Apnea: A Latent Class Analysis.

Rationale: Obstructive sleep apnea (OSA) is a heterogeneous syndrome with various endotypic traits and symptoms. A link among symptoms, endotypes, and disease prognosis has been proposed but remains unsupported by empirical data. Objectives: To link symptom profiles and endotypes by clustering endotypic traits estimated using polysomnographic signals. Methods: We recruited 509 patients with moderate to severe OSA from a single sleep center. Polysomnographic data were collected between May 2020 and January 2022. Endotypic traits, namely arousal threshold, upper airway collapsibility, loop gain, and upper airway muscle compensation, were retrieved using polysomnographic signals during non-rapid eye movement periods. We used latent class analysis to group participants into endotype clusters. Demographic and polysomnographic parameter differences were compared between clusters, and associations between endotype clusters and symptom profiles were examined using logistic regression analyses. Results: Three endotype clusters were identified, characterized by high collapsibility/loop gain, low arousal threshold, and low compensation, respectively. Patients in each cluster exhibited similar demographic characteristics, but those in the high collapsibility/loop gain cluster had the highest proportion of obesity and severe oxygen desaturation observed in polysomnographic studies. The low compensation cluster was characterized by fewer sleepy symptoms and exhibited a lower rate of diabetes mellitus. Compared with the excessively sleepy group, disturbed sleep symptoms were associated with the low arousal threshold cluster (odds ratio, 1.89; 95% confidence interval, 1.16-3.10). Excessively sleepy symptoms were associated with the high collapsibility/loop gain cluster (odds ratio, 2.16; 95% confidence interval, 1.39-3.37) compared with the minimally symptomatic group. Conclusions: Three pathological endotype clusters were identified among patients with moderate to severe OSA, each exhibiting distinct polysomnographic characteristics and clinical symptom profiles.

Severity, comorbidities, and adherence to therapy in Native Hawaiians/Pacific Islanders with obstructive sleep apnea.

Considerable disparities in the prevalence, diagnosis, and management of obstructive sleep apnea (OSA) exist for minority groups in the United States. However, the impact of OSA on Native Hawaiian/Pacific Islanders (NHPIs) has not been evaluated. We performed a retrospective review of patient records of NHPIs who underwent sleep apnea testing between 2014 and 2021 at a single center in Utah to characterize the distribution of comorbidities, disease severity, and treatment adherence. 140 of 141 NHPI patients who underwent sleep testing had OSA. High rates of obesity (94%) and other relevant comorbidities were found. OSA was mostly severe (57%), particularly in males with higher obesity. Adherence to continuous positive airway pressure was low (41% using for 4 or more hours on 70% of nights), and medical factors predicted whether adherence targets were met with modest accuracy (area under the curve 0.699). NHPIs at a single sleep center had a high prevalence of comorbidities in association with OSA, a skewed distribution toward severe disease suggestive of barriers to care or unique disease characteristics, and low adherence to continuous positive airway pressure. These findings suggest a high burden of OSA in this population, and further work to characterize barriers to identifying and treating OSA in NHPIs can improve chronic disease outcomes in NHPIs. Locke BW, Sundar DJ, Ryujin D. Severity, comorbidities, and adherence to therapy in Native Hawaiians/Pacific Islanders with obstructive sleep apnea. J Clin Sleep Med. 2023;19(5):967-974.

Contributing Factors of Excessive Daytime Sleepiness in Morbid Obese Patients with Obstructive Sleep Apnea

Background: Obesity, obstructive sleep apnea (OSA), and excessive daytime sleepiness (EDS) are common conditions and are interrelated. Obesity is a risk factor for OSA and independently associated with EDS. We aimed to evaluate frequency of EDS in morbid obese patients with OSA and to identify contribution factor for EDS.Methods: This was a retrospective cross-sectional study in single sleep center. Consecutive patients with OSA (with apnea-hypopnea index 5/h or more) with morbid obesity (body mass index over 35 kg/m2) was enrolled. EDS were defined as Epworth Sleepiness Scale of 10 points or more. Clinical and polysomnographic variables were compared between those with and without EDS.Results: Total 110 morbid obese patients with OSA were enrolled, and 34 (31%) of them had EDS. Those with EDS had higher subjective symptom of insomnia and depression. Rapid eye movement sleep latency was shorter and minimum saturation was lower for those with EDS. Multivariate logistic regression analysis identified insomnia severity (odds ratio, 1.117) and minimum saturation (odds ratio, 0.952) as independent contribution factor for EDS.Conclusions: Result of this study suggest that 31.4% of morbid obese patients with OSA have EDS, and it can be affected by insomnia severity and desaturation during sleep.

Prevalence of objective excessive daytime sleepiness in a cohort of patients with mild obstructive sleep apnea.

Obstructive sleep apnea (OSA) is common, yet the relationship between mild OSA and excessive daytime sleepiness (EDS) is unclear. Our objective was to determine the prevalence of objective EDS in a population withmild OSA using the mean sleep latency (MSL) from the multiple sleep latency test (MSLT). We retrospectively analyzed 1205 consecutive patients who underwent a polysomnography and a following day MSLT at a single sleep center. Adult patients who met criteria for mild OSA with an apnea-hypopnea index of 5 to <15 events/h were identified, and the percentage of patients with a MSL ≤ 8min was determined. Sleep study and demographic variables were examined to evaluate predictors of objective EDS. Of 155 patients with mild OSA, objective EDS was found in 36% (56/155) with an average MSL of 5.6 ± 2.1min in the objectively sleepy patients. Objectively sleepy patients withmild OSA had greater total sleep time (411.6 ± 48.9 vs. 384.5 ± 61.7min, p = 0.004), increased sleep efficiency (84.9 ± 9.7 vs. 79.7 ± 12.7%, p = 0.01), and decreased wake after sleep onset time (53.0 ± 36.9 vs. 67.4 ± 46.1min, p = 0.04) compared to patients withmild OSA but without objective EDS, with total sleep time being an independent predictor of MSL (p = 0.006). The Epworth Sleepiness Scale (ESS) weakly correlated with objective EDS (ρ = - 0.169, p = 0.03). There is a large subgroup of patients withmild OSA patients who have objective sleepiness. This may represent an ideal subgroup to target for future studies examining the effect of treatment in mild OSA. Additionally, the ESS was a poor predictor of this subgroup with mild OSA andobjective EDS.

Sleep time and efficiency in patients undergoing laboratory-based polysomnography.

Sleep quality in patients studied with laboratory-based polysomnography may differ from sleep quality in patients studied at home but remains clinically relevant and important to describe. We assessed objective sleep quality and explored factors associated with poor sleep in patients undergoing laboratory-based polysomnography. We reviewed diagnostic polysomnography studies from a 10-year period at a single sleep center. Total sleep time (TST) and sleep efficiency (SE) were assessed as markers of sleep quality. Poor sleep was defined as TST ≤ 4 hours or SE ≤ 50%. Multivariable analysis was performed to determine associations between objective sleep quality as an outcome and multiple candidate predictors including age, sex, race, body mass index, comorbidities, severity of obstructive sleep apnea, and central nervous system medications. Among 4957 patients (age 53 ± 15 years), average TST and median SE were 5.8 hours and 79%, respectively. There were 556 (11%) and 406 (8%) patients who had poor sleep based on TST and SE, respectively. In multivariable analysis, those who were older (per 10 years: 1.48 [1.34, 1.63]), male (1.38 [1.14,1.68]), and had severe obstructive sleep apnea (1.76 [1.28, 2.43]) were more likely to have short sleep. Antidepressant use was associated with lower odds of short sleep (0.77 [0.59,1.00]). Older age (per 10 years: 1.48 [1.34, 1.62]), male sex (1.34 [1.07,1.68]), and severe obstructive sleep apnea (2.16 [1.47, 3.21]) were associated with higher odds of poor SE. We describe TST and SE from a single sleep center cohort. Multiple demographic characteristics were associated with poor objective sleep in patients during laboratory-based polysomnography. Harrison EI, Roth RH, Lobo JM, et al. Sleep time and efficiency in patients undergoing laboratory-based polysomnography. J Clin Sleep Med. 2021;17(8):1591-1598.

0694 Positive Airway Pressure Use In The Context Of Total Sleep Time

Abstract Introduction Positive airway pressure (PAP) adherence definitions are independent of total sleep time (TST). When PAP efficacy is examined by biophysiologic outcomes in adults with obstructive sleep apnea (OSA), sensitivity and specificity of the measurement of PAP adherence/non-adherence is important. Methods A post-hoc analysis of experimental data: 1) investigated agreement among concurrently-measured objective PAP use, objective and subjective TST; 2) assessed untreated TST among adherers and non-adherers defined by CMS PAP adherence criterion and separately by proportion of TST on PAP criteria (≥65%, ≥75%, ≥85%). Objective TST was measured with wrist actigraphy and concurrent sleep diary on the first five days of PAP use. Objective five day PAP use (hours/night) was abstracted from full record. Analyses included descriptive and exploratory correlations. Results PAP-naïve adults (n=36; 76% male, 84% white) were middle-aged (51±10 years), with severe OSA (median AHI 31.1 events/hr), mean PAP use (371.5±85.4 min), mean objective and subjective TST (417.5±50.6 min, 439.6±58.1 min, respectively) from a single sleep center. Objective TST was correlated with concurrent objective PAP use (r=0.46) and with subjective TST (r=0.78). Eight percent (39mins) of objective TST was untreated among CMS-defined adherers, and 54.1% (216.8mins) of TST was untreated among CMS-defined non-adherers. When TST-on-treatment criteria were imposed (≥65%, ≥75%, and ≥85%, respectively), the percentage of untreated TST decreased among adherers, 5.2% (23 min), 4.3% (19 min), 0% (0 min) and among non-adherers, 42.8% (168 min), 41.2% (162 min), and 28.7% (118 min). From CMS to ≥85% of TST-on-treatment criteria, categorization as an adherer decreased from 89% (n=34) to 58% (n=22); non-adherer categorization increased from 5% (n=2) to 37% (n=14). Conclusion In the context of understanding biophysiological responses to PAP treatment, more sensitive and specific criteria for adherence and non-adherence is necessary. PAP use based on untreated TST is an opportunity to address this gap. Support The parent clinical trial was supported by NIH/NINR (R00NR011173; Sawyer PI)

The prevalence of restless sleep disorder in a single sleep center

The prevalence of restless sleep disorder in a single sleep center

0580 Obstructive Sleep Apnea and Daytime QT Interval by 12-Lead ECG

The association between obstructive sleep apnea (OSA) and sudden cardiac death (SCD) has been described. A prolonged QT interval is a recognized marker of abnormal ventricular repolarization linked to increased risk of SCD. We hypothesized that patients with OSA would have more marked abnormalities in daytime QT interval. We identified consecutive patients who underwent clinically indicated diagnostic polysomnography with a 12-lead ECG at a single academic sleep center. Heart rate-corrected QT intervals (QTc) were compared by OSA severity class (normal/mild: apnea hypopnea index (AHI) <15/hr; moderate: 15-30; severe: >30) adjusting for age, sex, body mass index, hypertension, and heart failure (HF). Further evaluation was performed by dichotomizing patients into severe (AHI >30/hr) and non-severe (<30/hr) OSA. Logistic analysis was used to determine the association of OSA severity and abnormal QTc (>450msec / >470msec for men/women, respectively). A total of 249 patients (50.2% female, mean age 57.2 [12.5]) were included. This cohort had a high burden of cardiovascular disease (73% with hypertension, 20% with HF). Abnormal QTc was present in 34% of males and 31% of females. QTc increased across OSA groups (normal/mild: 435.6 msec; moderate: 431.36; severe: 444.4, p= 0.03). Patients with severe OSA had longer QTc compared with normal/mild OSA (mean difference 10.0msec [0.5,19.0], p=0.04). When stratified dichotomously, patients with severe OSA had longer QTc compared to non-severe (444.4 msec vs. 433.48 msec, p=0.004). Severe OSA was also associated with abnormal QTc (OR 2.68 [1.34,5.48], p=0.006). There was significant interaction by HF status as the difference in QTc by OSA status (non-severe vs. severe) was more prominent in patients with HF (456.1 msec [435.3-476.8] vs. 480.5 [458.9-502.1], p=0.028). In a single sleep center cohort at elevated cardiovascular risk, patients with severe OSA had a prolonged daytime QTc compared to those with normal to mild OSA. Further, the prevalence of clinically significant abnormal QTc was higher in the severe (vs. non-severe) OSA group . The presence of severe OSA may represent a novel risk of SCD particularly in patients with HF. None

Atrial Fibrillation and Objective Sleep Quality by Slow Wave Sleep.

Self-reported poor sleep quality has been suggested in patients with AF. Slow wave sleep (SWS) is considered the most restorative sleep stage and represents an important objective measure of sleep quality. The aim of this study was to compare quantity of SWS between patients with and without AF. We included patients with and without a documented history of AF by reviewing clinically indicated polysomnography data from a single sleep center. Patients on medications with potential influence on sleep architecture were excluded. Logistic regression was performed to determine the association between AF and SWS time (low vs. high) adjusting for age, gender, body mass index, and sleep apnea. In a 2:1 case-control set-up, a total of 205 subjects (139 with AF, 66 without AF) were included. Mean age was 62 (SD: 14.3) years and 59% were men. Patients with AF had lower SWS time (11.1 vs. 16.6 min, p=0.02). In multivariable analysis, prevalent AF was associated with low SWS independent of sleep apnea and other potential confounders (OR 2.5 [1.3, 5.0], p=0.006). Limiting the analysis to patients whose total sleep time was greater than 4 hours (by excluding N=31) resulted in more robust results (OR 3.9 [1.7, 9.7]. p=0.002). AF is associated with more impaired sleep quality as indicated by lower quantity of SWS. More studies are needed to explore the mechanistic interactions between AF and sleep.

Mandibular Advancement Device as a Comparable Treatment to Nasal Continuous Positive Airway Pressure for Positional Obstructive Sleep Apnea.

Positional obstructive sleep apnea (P-OSA) is a clinically common phenotype of OSA, which can be treated effectively with mandibular advancement devices (MADs). We hypothesized that the efficacy of an MAD is comparable to that of nasal continuous positive airway pressure (nCPAP) in P-OSA patients. Among patients diagnosed with OSA at a single sleep center from January 2008 to May 2014, male subjects with moderate OSA were recruited and stringently categorized as having P-OSA when the ratio of their lateral apnea-hypopnea index (AHI) to supine AHI was ≤ 0.5, their lateral sleep time was > 60 minutes, and their lateral REM sleep time was longer than 10 minutes. Treatment efficacy was compared between P-OSA subjects with an MAD (n = 34) and those with nCPAP (n = 34) after matching for age, body-mass index, and baseline AHI. There were no significant differences in baseline AHI (MAD: nCPAP = 20.6 ± 3.9/h: 21.3 ± 1.7/h, p = 0.35) or in follow-up AHI (MAD: nCPAP = 4.7 ± 3.5/h: 3.4 ± 3.7/h, p = 0.12) between the 2 treatment groups, and hence MADs lowered the AHI to the same extent as nCPAP. These findings suggest that an MAD is as efficacious as nCPAP for P-OSA patients. MAD treatment for this specific phenotype may be a promising patient-tailored and first-line approach to OSA. A commentary on this article appears in this issue on page 1079.

Commercial Motor Vehicle Driver Positive Airway Pressure Therapy Adherence in a Sleep Center.

To assess positive airway pressure (PAP) therapy adherence in commercial motor vehicle (CMV) drivers presenting to a sleep center. A retrospective chart review of 120 drivers evaluated for obstructive sleep apnea OSA and 53 initiated on PAP therapy in a single sleep center over a one-year period (2012); PAP therapy data were collected up to 1 year. Early PAP usage best predicted adherence up to 1 year (p < 0.0001) compared to patient factors, OSA disease characteristics, and treatment elements analyzed. The proportion of participants adherent to therapy was 68.0% at 1 week, decreasing to 39.6% at 1 year, with 31.1% lost to follow-up by 1 year. In the group categorized based on adherence at week 1, 80.6% were adherent at 1 month, decreasing to 52.8% at 1 year. For the group non-adherent at 1 week, 29.4% were adherent at 1 month, decreasing to 11.7% at 1 year. Participants were predominantly male (75.8%), middle-aged (median 50.5 years), and African American (71.7%). Of those referred to the sleep center, 86.7% had OSA (median apnea-hypopnea index [AHI] or respiratory event index [REI] 20.1), with 51.0% of the OSA group having an AHI or REI > 20 and initiating PAP therapy. Early PAP utilization patterns predicted one year adherence for our CMV driver population within a sleep clinic setting. OSA testing of these CMV drivers after occupational health referral identifies high proportions of undiagnosed OSA, with approximately half requiring PAP therapy based on current published treatment recommendations.

Polysomnography Findings of Rapid Eye Movement Sleep Behavior Disorder in Korean Young Age Population

Objectives: Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia manifested by vivid dreams associated with complex motor behavior during REM sleep. It was originally described as a parasomnia in older men, however it is now recognized as a disorder of all ages and both sexes. We determine clinical characteristics of young age RBD patients who visited single sleep center in Korea. Methods: This is a retrospective chart review of RBD patients visiting single sleep center from August, 2003 to August, 2014. Patients with history of RBD were evaluated with overnight polysomnography (PSG). The PSG re sults were compared between young (<40 years old) and elderly (40 years or older). Results: The total of 149 patients (young RBD: n=22, 14.8%, elderly RBD: n=127, 85.2%) were included. Mean age upon diagnosis were 24.97±7.42 years (male: n=17, 77.3%) for young age RBD, and 64.40±8.73 years (male: n=82, 64.6%) for elderly RBD patients. PSG results reveled young age RBD patients had longer total sleep time (416.16±44.19, 345.73±78.03, p<0.001), higher sleep efficiency (87.60 ±6.90, 76.85±14.07, p<0.001), less arousal index (17.85±20.81, 23.14±12.15, p<0.001). Three patients in young age RBD group were also diag nosed with narcolepsy. Conclusions: This is the first study to evaluate PSG findings in young age RBD in Korean. The young age RBD sleep longer and better, with less arousal. Further on they have associated with sleep talking and walking, and narcolepsy. While few previous reports indicated association with medication use, our young age population was not related to medication effects. J Korean Sleep Res Soc 2014;11(2):57-60

Analysis of Recent Papers in Hypertension

Analysis of Recent Papers in Hypertension