Severe Sleep Apnea Research Articles

Differential effects of sleep position and sleep stage on the severity of obstructive sleep apnea.

This study compared the effects of sleeping in the supine position and rapid eye movement sleep on the severity of obstructive sleep apnea, and investigated the effect of sleep stage on position-dependent obstructive sleep apnea, and of sleep position on rapid eye movement-dependent obstructive sleep apnea. We analysed epoch-labelled polysomnographic readouts of 3843 patients, and calculated the apnea-hypopnea index for each sleep position and sleep stage. Subgroup analyses were performed to evaluate whether the proportion of position-dependent obstructive sleep apnea patients changed during rapid eye movement and non-rapid eye movement sleep, and whether that of rapid eye movement-dependent obstructive sleep apnea patients changed during supine/lateral sleep. The apnea-hypopnea index was highest in the rapid eye movement-supine position (50.7 ± 22.6 events per hr), followed by non-rapid eye movement-supine, rapid eye movement-lateral and non-rapid eye movement-lateral (39.2 ± 25.3, 22.9 ± 24.4, 15.9 ± 21.9 events per hr, respectively; p < 0.001). Patients with position-dependent obstructive sleep apnea had a higher ratio of rapid eye movement sleep, and those with rapid eye movement-dependent obstructive sleep apnea had a higher ratio of sleep time in the supine position (p < 0.001). During rapid eye movement sleep, position-dependent obstructive sleep apnea was not observed in 21.1% of patients who otherwise had position-dependent obstructive sleep apnea. In the lateral position, 36.9% of patients with rapid eye movement-dependent obstructive sleep apnea did not retain rapid eye movement dependency. Although sleeping in the supine position and rapid eye movement sleep were both associated with more frequent respiratory events, this was the first study to demonstrate that the former had a stronger correlation with obstructive sleep apnea severity. Position dependency in patients with obstructive sleep apnea decreased during rapid eye movement sleep, and worsening of rapid eye movement dependency was alleviated in the lateral position, suggesting potential for personalized obstructive sleep apnea management.

Tofogliflozin reduces sleep apnea severity in patients with type 2 diabetes mellitus and heart failure: a prospective study.

Sleep apnea (SA) is prevalent among patients with heart failure (HF) and contributes to a poor prognosis. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have demonstrated efficacy in reducing the risk of serious clinical events in patients with HF. Additionally, SGLT2 inhibitors may reduce the risk of incident SA and mitigate its severity in patients with cardiovascular disease and T2DM. We aimed to investigate whether the SGLT2 inhibitor tofogliflozin reduced the severity of SA, as assessed using the apnea-hypopnea index (AHI), in patients with HF and T2DM and whether a decrease in AHI correlates with changes in body composition and cardiorenal function parameters. This is a single-arm, prospective pathophysiologic study involving patients with HF, T2DM, and SA, defined as having an AHI of 15 events/h and more. SA was assessed using polysomnography. Changes in AHI before and 6 months after starting oral administration of tofogliflozin (20 mg) were assessed. Additionally, body composition and cardiorenal functions were assessed before and 6 months after tofogliflozin administration. Ten patients with HF, T2DM, and SA were finally enrolled (60% men, 66.9 ± 13.4 years). Tofogliflozin reduced AHI from 43.2 [30.2] to 35.3 [13.1] events/h (p = 0.024) at 6 months. Hemoglobin A1c, body weight, and body water content decreased significantly. However, no significant changes were observed in the cardiorenal function parameters. A linear relationship was observed between the changes in body water content and AHI (r = 0.642, p = 0.045). Tofogliflozin reduced AHI, possibly associated with a reduction in body water content.

The relationship between obstructive sleep apnea, dyspnea, and health-related quality of life in lung cancer survivors: a cross-sectional study in the Republic of Korea.

The purpose of this study was to explore the relationships among obstructive sleep apnea (OSA), dyspnea, and health-related quality of life (HRQOL), as well as the factors influencing HRQOL. A total of 129 lung cancer survivors (mean age, 53.4 years; 77 men and 52 women; mean time since diagnosis, 1.6 years; and cancer stage [1/2/3/4/relapse], 43/31/19/34/2, respectively) completed a questionnaire that included demographic and clinical information, as well as questions about the severity of sleep apnea, dyspnea, and HRQOL. The severity of OSA, dyspnea, and HRQOL were assessed using the Berlin questionnaire, the Dyspnea-10 item (FACIT-Dyspnea), and the European Organization for Research and Treatment of Cancer QLQ-C30, respectively. The severity of OSA and dyspnea exhibited negative correlations with HRQOL (p<0.05). Multiple regression analysis revealed that several factors significantly impacted the HRQOL of lung cancer survivors. These included the extent of dyspnea (β=-0.369, p<0.01), weight loss (β =0.192, p<0.01), OSA score (β =-0.215, p<0.01), stage 2 cancer (β =-0.181, p<0.01), and poor perceived health status (β=-0.179, p<0.05). These findings suggest that breathing difficulties, including OSA and dyspnea, contribute to decreased HRQOL. This study offers valuable insights for researchers and clinicians, aiding in the development of effective strategies to manage these issues in daily life.

Temporal and sleep stage-dependent agreement in manual scoring of respiratory events.

Obstructive sleep apnea diagnosis is based on the manual scoring of respiratory events. The agreement in the manual scoring of the respiratory events lacks an in-depth investigation as most of the previous studies reported only the apnea-hypopnea index or overall agreement, and not temporal, second-by-second or event subtype agreement. We hypothesized the temporal and subtype agreement to be low because the event duration or subtypes are not generally considered in current clinical practice. The data comprised 50 polysomnography recordings scored by 10 experts. The respiratory event agreement between the scorers was calculated using kappa statistics in a second-by-second manner. Obstructive sleep apnea severity categories (no obstructive sleep apnea/mild/moderate/severe) were compared between scorers. The Fleiss' kappa value for binary (event/no event) respiratory event scorings was 0.32. When calculated separately within N1, N2, N3 and R, the Fleiss' kappa values were 0.12, 0.23, 0.22 and 0.23, respectively. Binary analysis conducted separately for the event subtypes showed the highest Fleiss' kappa for hypopneas to be 0.26. In 34% of the participants, the obstructive sleep apnea severity category was the same regardless of the scorer, whereas in the rest of the participants the category changed depending on the scorer. Our findings indicate that the agreement of manual scoring of respiratory events depends on the event type and sleep stage. The manual scoring has discrepancies, and these differences affect the obstructive sleep apnea diagnosis. This is an alarming finding, as ultimately these differences in the scorings affect treatment decisions.

Obstructive sleep apnoea and lung function, and their association with nocturnal hypoxemia: results from the Swedish CArdioPulmonary bioimage Study (SCAPIS) – a cross-sectional study

Obstructive sleep apnoea (OSA) and its associations with lung function.BackgroundOSA is highly prevalent and characterised by abnormal respiration during sleep. This large, population-based study aimed to investigate the associations between OSA and lung function in subjects aged 50–64 years.MethodThe population-based Swedish CArdioPulmonary bioimage Study includes information on anthropometry, comorbidities and spirometry. The current analysis included data from three centres (Gothenburg, Umeå and Uppsala) on whole-night respiratory polygraphy as a meta-analysis examining the overall effect size of lung function on sleep apnoea severity, expressed as ß-coefficient after stratifying for sex and adjusting for age, waist circumference and smoking status.ResultsData from9016participants (54%women, age58±4 years, body mass index27±4 kg/m2) with sleep recordings of good quality were included in the final analysis. Forced expiratory volume during1 s(FEV1) (ß=−0.10 (95% CI −0.16 to −0.03)),forced vital capacity(FVC) (−0.15 (−0.21 to −0.10)) anddiffusion capacity for carbon monoxide(DLCO) (−0.08 (−0.10 to −0.05)) were all negatively associated with theoxygen desaturation index(ODI) and also with per cent of registration with nocturnal oxygen saturation&lt;90% FVC(−0.44 (−0.87 to −0.01)), FEV1(−0.86 (−1.36 to −0.36)) and DLCO(−0.47 (−0.60 to −0.35)). Additionally, a positive association was observed between FEV1(0.13 (0.05 to 0.22)) and DLCO(0.07 (0.04 to 0.09)) with the mean nocturnal saturation. There was a negative association between DLCOandapnoea-hypopnoea index, AHI, (ß=−0.04 (95% CI−0.06 to −0.03)), while no associations were found between FEV1or FVC and AHI.ConclusionIn OSA, lower lung function is more distinctly associated with the nocturnal hypoxic burden than AHI. Potential lung function impairment should be investigated in OSA patients with a high ODI relative to AHI.

Association Between Sleep Position, Obesity, and Obstructive Sleep Apnea Severity.

This study examines the relationship between obstructive sleep apnea severity, sleep position, and body weight, particularly focusing on the negative impact of sleeping in a supine position combined with being overweight in a population-based sample. The Apnea-Hypopnea Index (AHI) was utilized as a marker of OSA severity and sleep position from a standardized overnight polysomnography. Participants were categorized by body mass index (BMI) (kg/m2) into normal weight/underweight (<25) and overweight (≥25). The results indicated a higher mean Apnea-Hypopnea Index for those sleeping in the supine position compared to other positions, with overweight individuals experiencing a proportionally greater impact from sleep position than their normal-weight counterparts.

Vitamin D Deficiency and Pediatric Obstructive Sleep Apnea Severity

Prior research has demonstrated an association between vitamin D deficiency and obstructive sleep apnea (OSA) in adults; however, its association with pediatric OSA is emerging. To evaluate the association of vitamin D levels with obstructive Apnea-Hypopnea Index (AHI) in children with OSA. This was a cross-sectional study of children aged 2 to 16 years with severe obstructive OSA (AHI ≥20 on polysomnogram) who were undergoing adenotonsillectomy at a tertiary care pediatric otolaryngology clinic from 2017 to 2022. Age, sex, race, body mass index, history of asthma, and season were considered in the analyses. Data were analyzed from September 3, 2021, to October 8, 2021. Serum 25-hydroxyvitamin D (25[OH]D) levels were measured and assessed for correlation with polysomnography metrics. Fasting blood samples were collected and vitamin D deficiency was defined as 25(OH)D level less than 20 ng/mL. The consecutive sample included 72 patients (mean [SD] age, 6.7 [3.9] years; 34 [47.2%] females and 38 [52.8%] males). The mean (SD) AHI was 42.8 (25.5), and 35 participants (49.0%) had obesity. Vitamin D deficiency was present in 27 participants (37.5%). In univariate analysis, vitamin D deficiency was associated with younger age (difference, -5.0; 95% CI, -7.2 to -2.8), Black race (odds ratio [OR], 4.3; 95% CI, 1.4 to 14.3), female sex (OR, 4.8; 95% CI, 1.7 to 12.5), and higher obstructive AHI (difference, 13.8; 95% CI, 1.2 to 26.4). In multivariable analysis, vitamin D deficiency remained significantly associated with AHI. A 1.0-unit decrease in serum 25(OH)D levels was associated with an AHI increase of 0.7 (95% CI, 0.04 to 1.40). The findings of this cross-sectional study indicate that vitamin D deficiency was common in children undergoing adenotonsillectomy for severe OSA and is significantly associated with increased OSA severity. Future research is needed on vitamin D supplementation and its association with any improvements in pediatric OSA treatment outcomes.

Affecting factors and seasonal effects on the continuous positive airway pressure adherence of patients with obstructive sleep apnea

Continuous positive airway pressure (CPAP) is the preferred treatment for obstructive sleep apnea (OSA), but adherence remains challenging. This study identifies factors influencing CPAP adherence, including the impact of Korea's four distinct seasons. A retrospective study of 650 patients with OSA and prescribed with CPAP was conducted at a single institution from January 2018 to December 2020, and the patients' answers on various sleep questionnaires, demographic and polysomnographic data, and when and whether they returned the CPAP devices were collected and analyzed. The sample population was divided into when and whether the CPAP device was returned to the institution and the average daily use of the CPAP device. Results show that treatment failure is high in the first 12 weeks. Moreover, patients with more severe sleep apnea tended to have severe OSA-related clinical symptoms and are more likely to adhere to the treatment. In this study show that the seasons did not affect CPAP adherence because of indoor environmental factors. However, results show that other patient factors, such as BMI, AHI, RDI, daytime drowsiness, mood changes, and other OSA-related symptoms, have greater effects on CPAP adherence than seasonal change. Initial positive experience is important to adapt to the CPAP, and for this reason, more active intervention by sleep physicians during the initial CPAP adaptation is necessary.

Threshold-dependent association between non-rapid eye movement obstructive sleep apnea and interictal epileptiform discharges: A hospital study.

Obstructive sleep apnea frequently coexists with epilepsy, potentially influencing its pathophysiology. However, the effect of obstructive sleep apnea severity on interictal epileptiform discharges is not well understood. To explore this, we studied 108 Asian patients with epilepsy who underwent single-night polysomnography. We utilized generalized linear models, adjusting for age, sex, epilepsy type (focal versus generalized), antiepileptic medication use and disease duration, to analyse the relationship between obstructive sleep apnea severity, as measured by the apnea-hypopnea index, and interictal epileptiform discharge frequency during non-rapid eye movement and rapid eye movement sleep. Our analysis revealed that severe obstructive sleep apnea (apnea-hypopnea index ≥ 30) was associated with a higher frequency of interictal epileptiform discharges during non-rapid eye movement sleep (p = 0.04), but no such association was observed during rapid eye movement sleep. Additionally, the frequency of interictal epileptiform discharges in non-rapid eye movement sleep was positively correlated with the wake time between sleep onset and offset (p = 0.03). Further studies are warranted to validate our findings across diverse ethnicities, and over multiple nights of sleep and interictal epileptiform discharge recordings.

Time-Restricted Eating Versus Daily Calorie Restriction: Effect on Sleep in Adults with Obesity over 12 Months.

Objective: The aim of this secondary analysis was to compare the effects of time-restricted eating (TRE) versus daily calorie restriction (CR) on sleep quality, duration, insomnia severity, and risk of obstructive sleep apnea in adults with obesity over one year. Methods: A total of 90 participants were randomized to one of three groups for 12 months: 8 h TRE (eating only between 12 p.m. and 8 p.m.); CR (25% daily calorie restriction) or a no-intervention control group. Results: By the end of the study, weight loss was 4.61 kg (95% CI; 7.37 to 1.85 kg; p ≤ 0.01) for the TRE group and 5.42 kg (CI; 9.13 to 1.71 kg; p ≤ 0.01) for the CR group, with no statistically significant difference between TRE and CR (0.81 kg [CI; 3.07 to 4.69]; p = 0.68]). Self-reported sleep quality, sleep duration, insomnia severity, and risk of obstructive sleep apnea did not change in the TRE or CR groups versus controls by month 12. Conclusions: These findings suggest that the weight loss produced by TRE and CR does not have any impact on various sleep parameters in adults with obesity over one year.

6828 Exploring Metabolomic Clues in Diabetic Retinopathy

Abstract Disclosure: M.W. Simonson: None. Y. Li: None. J.J. McAnany: None. B. Prasad: None. E.C. Hanlon: None. S. Pannain: None. B.T. Layden: None. E. Van Cauter: None. J.C. Park: None. S.J. Crowley: None. F.Y. Chau: None. K.K. Danielson: None. H. Chen: None. G.E. Chlipala: None. C. Martinez: None. S. Reutrakul: Speaker; Self; Eli Lilly &amp; Company. Background: Diabetic retinopathy (DR) is a common microvascular complication of diabetes. Metabolomics offers the possibility for novel biomarker discovery. The purpose of this study was to determine metabolomic differences that characterized patients with versus without DR. Methods: A total of 62 serum samples were collected from 36 type 2 diabetes (T2D) patients with DR and 26 T2D patients without DR, and analyzed via UPLC-MS. The metabolite data were normalized using median normalization. The differential expression of metabolites was compared among the groups using the limma package in R. The covariates (age, sex, BMI and sleep apnea severity) were accounted for by using a generalized linear model fitted to the data. Significantly different metabolites were filtered by an absolute log2 Fold Change (FC) of 1.5 or greater and Q values &amp;lt; 0.05. Results: Mean (SD) age for DR and no-DR group was 55 (±5.9) versus 54 (±6.7) years, while BMI was 33 (±5.8) versus 33 (±6.3) kg/m2 respectively. Both DR and no-DR groups were 58% female. A1C levels in DR group was marginally higher than in no-DR group (p=0.09). There were significant differences in metabolomic changes between DR versus no-DR, with 166 total differential metabolites after adjusting for covariates and filtering by FC. Notable metabolites included those involved in fatty acid metabolism, acyl carnitines, prostaglandins, and phospholipids. There was an overall upregulation of serum acyl carnitines in DR as compared to no-DR, including 2,6 dimethylheptanoyl carnitine (FC = 3.0) and cis-5-Tetradecenoylcarnitine (FC = 2.0). Additionally, there was a decrease in long chain fatty acids in DR as compared to no-DR, which included 6-hydroxypentadecanedioic acid (FC = -6.6), 10,16-dihydroxy-palmitic acid (FC = -6.0), and tetracosatetraenoyl CoA (FC = -6.1). The 11-beta prostaglandin F2 (11-PGF2) was increased in DR (FC = 1.9). Circulating phospholipids including lysophosphatidylcholine (22:2) (lysoPC) (FC = 1.8) and phosphatidylcholine (24:1/24:1) (PC) (FC = 5.9) were also significantly dysregulated. Conclusions: We identified a subset of metabolites that discriminate T2D patients with or without DR. The changes in acyl carnitines and long chain fatty acids may reflect mitochondrial dysfunction in DR. The presence of certain prostaglandins highlights the inflammatory environment which may facilitate DR progression. Increases in phospholipids such as lysoPC suggest an atherogenic state and higher LDL oxidation, while increases in PC may indicate altered lipogenesis in DR. These findings may serve as new potential serum biomarkers to promote efficient preventive care and provide mechanistic insight into understanding DR pathophysiology. Presentation: 6/2/2024

Posterior fossa decompression in patients with Chiari malformation type 1: effect on sleep apnea and follow-up outcomes.

Sleep apnea, posing significant health risks, is frequently associated with Chiari malformation (CM), characterized by cerebellar tonsil herniation through the foramen magnum. Central sleep apnea (CSA) in CM results from impaired brain-to-muscle signaling and requires treatment. Conversely, obstructive sleep apnea (OSA), arising from throat muscle relaxation, typically unrelated to CM, often coexists. This study evaluates the effectiveness of posterior fossa decompression (PFD) on sleep apnea. A retrospective chart review was conducted of pediatric patients with CM-1 and sleep apnea who underwent PFD between April 1, 2004, and September 30, 2022. Data collected included demographics, clinical characteristics, adenotonsillectomy status, PFD details, and sleep study parameters like the apnea-hypopnea index and respiratory disturbance index. Statistical analysis assessed the surgery's impact on sleep apnea severity. The study included eleven patients, predominantly male (63.6%). All had OSA (100%), with 63.6% also having CSA. Preoperative sleep studies classified OSA severity as 36.4% mild, 18.2% moderate, and 45.5% severe, with no change post-surgery. CSA severity initially included seven mild cases, which became three mild, one moderate, and three resolved cases post-surgery. Among seven patients who had adenotonsillectomy before decompression, five showed no improvement in OSA severity post-surgery. This study elucidates the complex relationship between CM-1, sleep apnea, and PFD. The findings show the persistence of sleep apnea in some patients and highlight the need for continuous monitoring of these patients in order to optimize their care after surgery.

Deep learning approaches for assessing pediatric sleep apnea severity through SpO2 signals

Pediatric Sleep Apnea–Hypopnea (SAH) presents a significant health challenge, particularly in diagnostic contexts, where conventional Polysomnography (PSG) testing, although effective, can be distressing for children. Addressing this, our research proposes a less invasive method to assess pediatric SAH severity by analyzing blood oxygen saturation (SpO2) signals. We adopted two advanced deep learning architectures, namely ResNet-based and attention-augmented hybrid CNN-BiGRU models, to process SpO2 signals in a one-dimensional (1D) format for Apnea–Hypopnea Index (AHI) estimation in pediatric subjects. Employing the CHAT dataset, which includes 844 SpO2 signals, the data was partitioned into training (60%), testing (30%), and validation (10%) sets. A predefined validation subset was randomly selected to ensure the models' robustness via a threefold cross-validation approach. Comparative analysis revealed that while the ResNet model attained an average accuracy of 72.9% across four SAH severity categories with a kappa score of 0.57, the CNN-BiGRU-Attention model demonstrated superior performance, achieving an average accuracy of 75.95% and a kappa score of 0.63. This distinction underscores our method's efficacy in both estimating AHI and categorizing SAH severity levels with notable precision. Further, to evaluate diagnostic capabilities, the models were benchmarked against common AHI thresholds (1, 5, and 10 events/hour) in each test fold, affirming their effectiveness in identifying pediatric SAH. This study marks a significant advance in the field, offering a non-invasive, child-friendly alternative for pediatric SAH diagnosis. Although challenges persist in accurately estimating AHI, particularly in severe cases, our findings represent a critical stride towards improving diagnostic processes in pediatric SAH.

Characterization of sleep apnea among a sample of adults from Samoa

Sleep apnea is a global public health concern, but little research has examined this issue in low- and middle-income countries, including Samoa. The purpose of this study was to examine the sample prevalence and characteristics of sleep apnea using a validated home sleep apnea device (WatchPAT, Itamar) and explore factors that may influence sleep health in the Samoan setting. This study used data collected through the Soifua Manuia (“Good Health”) study, which investigated the impact of the body mass index (BMI)-associated genetic variant rs373863828 in CREBRF on metabolic traits in Samoan adults (sampled to overrepresent the obesity-risk allele of interest). A total of 330 participants had sleep data available. Participants (53.3 % female) had a mean (SD) age of 52.0 (9.9) years and BMI of 35.5 (7.5) kg/m2, and 36.3 % of the sample had type 2 diabetes. Based on the 3 % and 4 % apnea hypopnea indices (AHI) and the 4 % oxygen desaturation index (ODI), descriptive analyses revealed moderate to severe sleep apnea (defined as ≥15 events/hr) in 54.9 %, 31.5 %, and 34.5 % of the sample, respectively. Sleep apnea was more severe in men (e.g., AHI 3 % ≥15 in 61.7 % of men and 48.9 % of women). Correction for non-representational sampling related to the CREBRF obesity-risk allele resulted in only slightly lower estimates. Multiple linear regression linked a higher number of events/hr to higher age, male sex, higher BMI, higher abdominal-hip circumference ratio, and geographic region of residence. Further research and an increased focus on equitable and affordable diagnosis and access to treatment are crucial to addressing sleep apnea in Samoa and globally.

Obstructive sleep apnoea is independently associated with non-alcoholic fatty pancreatic disease

Purpose This study investigated the prevalence of non-alcoholic fatty pancreatic disease (NAFPD) in patients with obstructive sleep apnoea (OSA) and analysed the correlation between them. Materials and methods Patients who underwent polysomnography and modified abdominal ultrasound examinations were continuously enrolled and divided into OSA and control groups. The OSA group was further divided into NAFPD and non-NAFPD groups. Differences in various indicators were compared. Binary logistic regression analyses were conducted to identify factors influencing NAFPD. Results A total of 210 participants were included in the study, including 178 in the OSA group and 32 in the control group. The prevalence of NAFPD, weight, body mass index (BMI), and other indicators were significantly higher in the OSA group than that in the control group (p < 0.05). The above indices, prevalence of hypertension and metabolic associated steatotic liver disease (MASLD), and severity of sleep apnoea were higher in the NAFPD group than that in the non-NAFPD group (p < 0.05). Binary logistic regression analysis showed a 4.4% increased risk of NAFPD for each unit increase in apnea-hypopnea index (AHI) after adjusting for BMI and hypertension. Conclusion The prevalence of NAFPD was higher in the OSA group than that in the control group, and chronic intermittent hypoxia was strongly associated with pancreatic fat infiltration; AHI, BMI, and hypertension were independent risk factors for NAFPD. The NAFPD group had a higher prevalence of obesity and some other diseases.

The Association Between Obesity and the Development and Severity of Obstructive Sleep Apnea: A Systematic Review.

Obesity has reached epidemic proportions globally, accompanied by a parallel rise in the incidence of obstructive sleep apnea (OSA). Thesystematic study aims to assess the association between obesity and the onset and severity of OSA. A comprehensive computerized search of pertinent databases was done to find studies that fit the inclusion requirements. A comprehensive search was carried out on PubMed, SCOPUS, Science Direct, Systematic Library, and Web of Science to locate relevant material. Our data included 12 trials with 4095 participants, and 1456 (35.6%) were men. In individuals who were obese, the prevalence of OSA varied from 12.6% to 88.9%, with a total prevalence of 1291 (31.5%). One major factor that determined the level of OSA was obesity. It was consistently discovered by studies that there was a positive correlation between body mass index (BMI), and measures such as the Apnea-Hypopnea Index (AHI) are crucial in determining the extent of OSA. Besides, it was also observed that these comorbid conditions made OSA more severe and difficult to manage. Variability in findings suggests the influence of additional factors such as age, sex, and ethnicity on the obesity-OSA relationship. This comprehensive study offers strong evidence that OSA development and severity are significantly influenced by fat. The results emphasize the significance of weight control, especially for obese people, in treating and preventing OSA.

Atomoxetine and spironolactone combine to reduce obstructive sleep apnea severity and blood pressure in hypertensive patients.

Norepinephrine reuptake inhibitors such as atomoxetine (ato) can improve OSA by increasing pharyngeal muscle activity. Mineralocorticoid antagonists such as spironolactone, may potentiate the reduction of OSA severity and reduce blood pressure. We evaluated whether adding spironolactone to atomoxetine (ato-spiro) improved responses in hypertensive OSA patients. Twenty-one patients with an apnea-hypopnea index (AHI) between 10 and 50 events/h and a history of hypertension were recruited and crossed-over in random order to ato 80mg and ato-spiro 80/50mg for 1 week after a 3-day low dose run-in period. Two dropped out due to drug related side effects. Polysomnography and 24-hour blood pressure (BP) monitoring were performed at baseline and after each treatment period. AHI decreased on both ato and ato-spiro from a baseline median(IQR) of 20.3(18.8 to 28.5) to 8.2(7 to 13.1) and 6.2(5.7 to 14.1), respectively (p < 0.001 for both). Systolic BP (mmHg) fell by mean(95%CI) -4.5(-13.8 to 4.8, p = 0.33) on ato and - 10.3(-19.2 to -1.5, p = 0.02) on ato-spiro, and diastolic BP dropped by -3.0(-8.0 to 2.0, p = 0.23) on ato and - 5.0(-9.1 to -0.9; p = 0.02) on ato-spiro. Both ato and ato-spiro led to a significant shift from apnea to hypopnea predominance (p < 0.001), and significant reductions in hypoxic burden (p ≤ 0.001) and REM sleep (p ≤ 0.001). Both ato-spiro and ato alone decreased OSA severity similarly, but ato-spiro led to even greater, statistically significant and clinically meaningful falls in systolic and diastolic BP. BP reductions were likely due to ato-related improvements in upper airway patency and hypoxemia, and to spiro-related reduced fluid retention. These findings show promise for ato-spiro as an oral treatment for hypertensive OSA patients. REGISTERED AT CLINICALTRIALS.GOV: NCT04905979.

Kairos positive airway pressure (KPAP) equals continuous PAP in effectiveness, and offers superior comfort for obstructive sleep apnea treatment

Study objectivesA recent study challenged the prevailing clinical view that maintaining inspiratory positive airway pressure (IPAP) is necessary for upper airway patency, demonstrating no differences in apnea hypopnea index (AHI) between continuous PAP (CPAP) with and without a resistor to reduce IPAP. In this study, we assessed the effect of Kairos PAP (KPAP), a new algorithm which features multiple drops in IPAP, only returning to therapeutic pressure near the end expiration, on sleep apnea severity and subjective comfort. MethodsTwo randomized clinical trials were conducted. In the Efficacy trial, the effect of KPAP vs. CPAP on AHI in PAP-treated OSA patients was examined using a split-night design, adjusting for period, sequence and fraction of supine sleep (mixed models). Unintentional leak differences between treatments were also examined. Exploratory analyses assessed the effect of KPAP vs. CPAP on key polysomnography outcomes. In the Comfort trial, we tested subjective preference for KPAP vs. CPAP at 9 and 13 cmH2O in PAP-naïve OSA patients. ResultsIn the Efficacy trial (N = 48), KPAP reduced AHI more than CPAP (mean difference [95%CI]: −0.5 [−0.8, −0.2] events/h, P = 0.007). Unintentional leak was also reduced by over 50 % (−2.5 [−3.2, −1.7] L/min, P < 0.001). No significant change was observed in the exploratory variables assessed. In the Comfort trial (N = 150), 69 [61, 77] % and 84 [77, 89] % of participants preferred KPAP over CPAP at 9 and 13 cmH2O, respectively (P < 0.001). ConclusionsKPAP is as effective as CPAP in reducing respiratory events, but is more comfortable and potentially better tolerated.

Analysis of the characteristics of intestinal microbiota in patients with different severity of obstructive sleep apnea

Intestinal microbiota imbalance plays an important role in the progression of obstructive sleep apnea (OSA), and is considered to be the main mediator that triggers metabolic comorbidities. Here, we analyzed the changes in intestinal microbiota in patients with different severities of OSA based on apnea hypopnea index (AHI) classification, and explored the role of intestinal microbiota in the severity of OSA. This study included 19 healthy volunteers and 45 patients with OSA [5 ≤ AHI < 15 (n = 14), 15 ≤ AHI < 30 (n = 13), AHI ≥ 30 (n = 18)]. Relevant sleep monitoring data and medical history data were collected, and microbial composition was analyzed using 16S rRNA high-throughput sequencing technology. The diversity analysis of intestinal microbiota among different groups of people was conducted, including alpha diversity, beta diversity, species diversity, and marker species as well as differential functional metabolic pathway prediction analysis. With the increase of AHI classification, the alpha diversity in patients with OSA significantly decreased. The results revealed that the severity of OSA is associated with differences in the structure and composition of the intestinal microbiota. The abundance of bacteria producing short-chain fatty acids (such as Bacteroides, Ruminococcacea, and Faecalibacterium) in severe OSA is significantly reduced and a higher ratio of Firmicutes to Bacteroidetes. Random forest analysis showed that Parabacteroides was a biomarker genus with important discriminatory significance. The differential metabolic pathway prediction function shows that the main function of maintaining intestinal microbiota homeostasis is biosynthetic function. Our results show that the differences in the composition of intestinal microbiota in patients with different severities of OSA are mainly related to short-chain fatty acid-producing bacteria. These changes may play a pathological role in OSA combined with metabolic comorbidities.

Aerobic exercise training and obstructive sleep apnea: dose-response meta-analyses.

Several studies have shown that aerobic exercise training improves obstructive sleep apnea (OSA) severity. However, a dose-response relationship has never been shown. This study aimed to quantify any dose-response relationships between time spent per week in aerobic exercise and key sleep apnea outcomes. Randomized controlled trials (RCT) were selected from literature search studying the effects of supervised aerobic exercise training on patients with OSA. Dose-response meta-analyses were performed, where the 'dose' was the total weekly duration of aerobic exercise training. Primary outcomes were apnea hypopnea index (AHI), cardiorespiratory fitness (maximum oxygen consumption or VO2peak) and Epworth Sleepiness Scale (ESS). Analysis of data from 11 RCTs showed a non-linear dose-response relationship between the total weekly duration of aerobic exercise training and mean differences in AHI. Maximum effects on AHI (-10.92 (95%CIs: -15.57; -6.27)) were observed when the weekly duration of aerobic exercise reached 100min/week. Similar non-linear dose-response trend was observed in the mean differences in VO2peak. Studies in which aerobic exercise training lasted ≥ 12 weeks showed greater proportional changes in mean AHI differences with maximal effects reaching a peak at ∼ 70min/week of aerobic exercise training. ESS and total weekly duration of aerobic exercise training showed a linear dose-response relationship based on 4 RCTs. Based on these analyses, aerobic exercise training of 70-100min/week over 3 or 5 days a week should be recommended as adjunctive treatment for patients with OSA.