Severe Sleep Apnea Research Articles

Impact of lifestyle interventions targeting physical activity and healthy diet on treatment of Obstructive Sleep Apnea (OSA)

Introduction and purpose: Obstructive Sleep Apnea Syndrome (OSAS) is a worldwide prevalent sleep-related medical condition characterised by upper airway collapse, leading to hypoxia and hypercapnia. Excess body weight is the risk factor of OSAS. Lifestyle interventions, particularly targeting weight loss, have emerged as potential management strategies for OSAS. The purpose of this review is to compile the information about the effectiveness of different forms of lifestyle interventions in the treatment of OSA. Brief description of the state of knowledge: While CPAP remains the current “gold standard” treatment of Obstructive Sleep Apnea, it’s not always well-tolerated. Consequently, lifestyle interventions such as dietary modifications, exercise programs, and behavioural therapies have emerged as important components in the management of this disease. The research has shown that these strategies not only reduce the severity of OSA but also improve quality of life. Summary: Lifestyle interventions, including dietary modifications, exercise programs, and behavioral therapies targeting weight loss, have demonstrated promising results in reducing the severity of obstructive sleep apnea (OSA) and alleviating associated symptoms. However, further large-scale, long-term studies are necessary to validate their efficacy and understand their broader impact on OSA management.

Assessment of airflow limitation in patients with obstructive sleep apnea

BackgroundObstructive sleep apnea (OSA) is a prevalent sleep breathing disorder affecting 9–25% of the general adult population.AimTo assess airflow limitation by spirometric indices in patients with obstructive sleep apnea.Patients and methodsThis observational case–control study was conducted on 60 subjects who were divided into four groups: Group I (control group), included 20 subjects chosen from other departments, who had no respiratory complaints with apnea–hypopnea index (AHI < 5); Group II (mild group), included 11 patients with mild sleep apnea, 5 ≤ AHI < 15; Group III (moderate group), included 17 patients with moderate sleep apnea, 15 ≤ AHI < 30; and Group IV (severe group), included 12 patients with severe sleep apnea, AHI ≥ 30 at the Chest Department, Faculty of Medicine, Helwan University, from August 2021 until June 2022.ResultsThere was no statistically significant relation found between the severity of AHI and all the previous pulmonary function parameters except a statistically significant decrease in FEF (25–75%) in the moderate group than the mild group and also in the severe group than the moderate group (p-value < 0.001). There was a statistically significant positive correlation found between AHI and BMI and NC and a negative correlation found between AHI and FEF (25–75%) while no statistically significant correlation was found between AHI and the other studied parameters.ConclusionObstructive sleep apnea (OSA) is associated with airflow limitation by spirometric indices, although this association is statistically insignificant. On the other hand, the severity of obstructive sleep apnea is directly proportional to the seriousness of the apnea–hypopnea index (AHI). Strong correlations were found between the severity of AHI and body mass index (BMI), neck circumference, and FEF (25–75%).

Does the severity of obstructive sleep apnea increase the risk of cancer? Clues in apnea-hypopnea index and biomarkers.

Does the severity of obstructive sleep apnea increase the risk of cancer? Clues in apnea-hypopnea index and biomarkers.

Sleep Apnea, Autonomic Disturbances, and Blood Pressure Variability.

Augmented blood pressure variability has emerged as a quantity predictive of adverse cardiovascular outcomes. Among the range of intrinsic and extrinsic factors shown to increase night-time, circadian, short-term, and long-term blood pressure variations, the presence and severity of obstructive sleep apnea have emerged as one of the most prevalent and potent. Obstructive sleep apnea alters acutely the normal nocturnal equilibrium between sympathetic and parasympathetic tone, magnifying nocturnal blood pressure oscillations, and induces sustained autonomic aftereffects with the capacity to amplify short-term and intersessional blood pressure variabilities. The object of this brief review is to synthesize the current understanding of the potential interrelations between obstructive sleep apnea, the acute and sustained autonomic disturbances that it elicits, and beat-to-beat blood pressure fluctuation during sleep, nocturnal dipping status, and day-to-day blood pressure variability and the consequences of these perturbations for cardiovascular risk.

Clinical Characteristics of Patients With Idiopathic Intracranial Hypertension in China.

Introduction Idiopathic intracranial hypertension (IIH) was previously assumed to be rare in Asia. However, it has been increasingly recognized in China in recent years, likely due to pandemic obesity and greater awareness of the condition. The clinical characteristics of IIH in Chinese patients remain unexplored. This study aims to investigate the clinical characteristics of patients with IIH in China. Methods A retrospective chart review of patients diagnosed with IIH at the First Affiliated Hospital of Zhengzhou University was conducted from January 2013 to July 2021.The analysis included demographic data, presenting symptoms, comorbidities, imaging features, laboratory data, intracranial pressure (ICP), treatment modalities, and outcomes. Results The study recruited 199 participants, including 145 females and 54 males, with a mean age at onset of 36 years (range: 27 to 45 years). The participants had a mean body mass index (BMI) of 26 kg/m2 (range: 23.4 to 29.4 kg/m2). Obesity was found in 67 participants (33.7%). The most common clinical symptom reported was headache, which was experienced by 118 (59.3%) participants, followed by decreased vision, which was reported by 115 (57.8%) participants. The main comorbidity among women was anemia (54, 37.2%), while men were more likely to have severe sleep apnea (7, 13%). The most common imaging features were perioptic nerve sheath distension (159, 79.9%) and transverse sinus stenosis (147, 73.9%). Symptoms were relieved with medication in 117 (58.8%) participants, while 72 (36.2%) underwent surgeries such as venous sinus stenting and ventriculoperitoneal shunt. During follow-up, symptoms resolved in 84 (42.2%) participants, while 115 (57.8%) participants experienced symptom improvement. The ratio of decreased vision was higher in females than in males. Conclusion The results provide valuable insights into the clinical features of IIH in this region. China appears to have a lower incidence of obesity compared to Western countries. Among comorbidities related to IIH, anemia and severe sleep apnea were the most common. A significant number of IIH patients underwent surgery. It was found that women had worse visual outcomes compared to men. Further investigation is needed to determine the most effective treatment for IIH in a larger cohort of Chinese patients.

Estimating the Severity of Obstructive Sleep Apnea Using ECG, Respiratory Effort and Neural Networks.

wearable sensor technology has progressed significantly in the last decade, but its clinical usability for the assessment of obstructive sleep apnea (OSA) is limited by the lack of large and representative datasets simultaneously acquired with polysomnography (PSG). The objective of this study was to explore the use of cardiorespiratory signals common in standard PSGs which can be easily measured with wearable sensors, to estimate the severity of OSA. an artificial neural network was developed for detecting sleep disordered breathing events using electrocardiogram (ECG) and respiratory effort. The network was combined with a previously developed cardiorespiratory sleep staging algorithm and evaluated in terms of sleep staging classification performance, apnea-hypopnea index (AHI) estimation, and OSA severity estimation against PSG on a cohort of 653 participants with a wide range of OSA severity. four-class sleep staging achieved a κ of 0.69 versus PSG, distinguishing wake, combined N1-N2, N3 and REM. AHI estimation achieved an intraclass correlation coefficient of 0.91, and high diagnostic performance for different OSA severity thresholds. this study highlights the potential of using cardiorespiratory signals to estimate OSA severity, even without the need for airflow or oxygen saturation (SpO2), traditionally used for assessing OSA. while further research is required to translate these findings to practical and unobtrusive sensors, this study demonstrates how existing, large datasets can serve as a foundation for wearable systems for OSA monitoring. Ultimately, this approach could enable long-term assessment of sleep disordered breathing, facilitating new avenues for clinical research in this field.

The association of diabetes with progression of sleep-disordered breathing based on a prospective cohort.

Prospective studies suggest that sleep-disordered breathing enhances the risk of diabetes. However, it remains unclear whether diabetes could worsen sleep-disordered breathing. The participants from Sleep Heart Health Study underwent two polysomnograms at a 5-year interval. The relationship of baseline diabetes to change in the apnoea-hypopnoea index (AHI) was examined based on general linear models, adjusting for demographics, lifestyles, history of hypertension, pulmonary function, length of follow-up and baseline AHI. In total, 161 of the 2603 participants were diagnosed with diabetes at the first polysomnograms. Compared with participants without diabetes, those with diabetes had a higher baseline and larger increases in follow-up AHI and obstructive apnoea index (oAI). Diabetes increased 2.52 events per hour (95% confidence interval 0.45-4.59; p = .017) for AHI change and 1.13 events per hour (95% confidence interval 0.04-2.23; p = .042) for oAI change, respectively. In addition, subgroup analysis suggested that the association was consistent across baseline obstructive sleep apnoea severity and body mass index groups. Baseline diabetes was associated with worsening sleep-disordered breathing over 5 years, which mainly increased the change in AHI and oAI.

Sleep and Daytime Function in People with Spinal Cord Injury.

Cross-sectional cohort study. To determine the role of sleep-disordered breathing (SDB), insomnia symptoms and sleep quality in the daytime function and quality of life of veterans with spinal cord injury (SCI). A Veterans Administration (VA) medical center in the Midwestern US. Thirty-eight male veterans with SCI (22 cervical, 16 thoracic; mean [SD] age = 62.9[9.5] years) completed baseline assessments within a larger clinical trial. Measures assessed sleep apnea severity (apnea-hypopnea index, AHI), insomnia symptoms (Insomnia Severity Index, ISI), self-reported sleep quality (Pittsburg Sleep Quality Index, PSQI), daytime sleepiness (Epworth Sleepiness Scale, ESS), fatigue (Flinders Fatigue Scale, FFS), depression (Patient Health Questionnaire-9 item, PHQ-9 excluding sleep item), functioning (Spinal Cord Independence Measure, SCIM), and quality of life (World Health Organization Quality of Life, WHOQOL-BREF). Bivariate correlations (alpha p<.05) were used to assess relationships between sleep (AHI, ISI, PSQI, ESS) and function (FFS, PHQ-9, SCIM, WHOQOL-BREF). Mean AHI was 29.9(26.6), mean ISI was 9.38(6.2), mean PSQI was 9.0(4.6), and mean ESS was 7.0(5.2). There were no significant relationships between AHI and function measures. Significant relationships emerged between ISI and PHQ-9, some WHOQOL-BREF subscales, and SCIM as well as between PSQI and FFS, PHQ-9, and some WHOQOL-BREF subscales. Among Veterans with SCI, insomnia symptom severity and poor sleep quality were associated with worse functioning, whereas SDB severity was not. Insomnia and poor sleep quality represent modifiable contributors to poor daytime function. Research evaluating the impact of evidence-based insomnia treatments among individuals living with SCI is warranted.

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.

Influence of sleep stages on determining positional dependency in patients with obstructive sleep apnea.

Supine sleep position and rapid eye movement (REM) stage are widely known to aggravate the severity of obstructive sleep apnea (OSA). In general, position-dependent OSA is defined as an apnea-hypopnea index (AHI) at least twice as high in the supine position as in other sleep positions, but it can be misdiagnosed if a certain sleep stage, REM or NREM, is dominant in a specific sleep position. In this study, we investigated the influences of the sleep stages on positional dependency. The polysomnographic data from 111 OSA patients aged ≥ 18 years (AHI > five events/hour) who slept in both supine and non-supine positions (each ≥ 5% of the total sleep time) were retrospectively analyzed. The overall ratio of non-supine AHI/supine AHI (NS/S AHI ratio) during the entire sleep was compared between specific sleep stages, i.e., REM or NREM sleep. Additionally, the weighted NS/S AHI ratio reflecting the proportion of each sleep time was created and compared with the original NS/S AHI ratio. The mean value of the NS/S AHI ratio did not differ between the entire sleep and the specific sleep stages. However, those ratios in the individual patients showed poor agreement of the NS/S AHI ratios between the entire sleep and the specific sleep stages. The weighted NS/S AHI ratio also demonstrated poor agreement with the original NS/S AHI ratio, mainly due to the discrepancy in mild to moderate OSA patients. The weighted NS/S AHI ratio might help assess precise positional dependency.

Deep learning framework for automatic detection and classification of sleep apnea severity from polysomnography signals

Deep learning framework for automatic detection and classification of sleep apnea severity from polysomnography signals

Association between obstructive sleep apnea severity and depression risk: a systematic review and dose-response meta-analysis.

Obstructive sleep apnea (OSA) has received considerable attention as a potential risk factor for depressive symptoms. The systematic review was conducted to confirm the dose‒response connection between OSA severity and depression risk. A systematic literature search of English and Chinese articles published in PubMed, EMBASE, Scopus, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and SinoMed databases from their inception to 28 August 2023 was conducted. An evaluation using the Newcastle‒Ottawa Scale was performed. A meta-analysis was used to evaluate the impact of OSA severity. A random-effects dose‒response model was conducted to evaluate the linear and nonlinear dose‒response connections. We evaluated publication bias by funnel plots, and symmetry by Egger's test. We identified 18 cross-sectional researches. 3143 participants which were involved in the dose‒response meta-analysis. Contrasted with mild OSA, individuals with severe OSA had a higher adjusted risk of depression (rate ratio: 1.34, 95% confidence interval = 1.05-1.70), with substantial heterogeneity (I2 = 70.9%, Pheterogeneity<0.001). There is a significant linear connection between OSA severity and depression risk. The depression risk increased by 0.4% for every 1 event per hour increase in the apnea-hypopnea index (AHI). The protocol for this unfunded research was drafted and registered at PROSPERO (ID CRD42023474097).

Influence of Economic Connectedness on Pediatric Obstructive Sleep Apnea Severity and Adenotonsillectomy Outcomes.

To examine the influence of economic connectedness (EC), a measure of social capital, on obstructive sleep apnea (OSA) severity and adenotonsillectomy outcomes in children. Retrospective study. Single tertiary medical center. The study population included 286 children who were referred for full-night polysomnography for OSA and underwent adenotonsillectomy. The primary outcome was the relationship between EC and the presence of severe OSA, and secondary outcomes included postoperative emergency room visits and residual OSA after adenotonsillectomy. Linear regression, Kruskal-Wallis test, Pearson's χ2 test, and multiple logistic regression were used for categorical and continuous data as appropriate. In this population, the median age was 9.0 (interquartile range [IQR] = 6.9-11.7) and 144 (50.3%) were male. The majority were white (176, 62.0%), black (60, 21.1%), and/or of Hispanic ethnicity (173, 60.9%). The median EC of this population was 0.64 (IQR = 0.53-0.86). Higher EC was associated with decreased odds of having severe OSA (odds ratio: 0.17, 95% confidence interval = 0.05-0.61). However, EC was not associated with either postoperative emergency room visits or residual OSA. EC was significantly associated with severe OSA (ie, apnea-hypopnea index ≥ 10) but not with postoperative emergency room visits or residual OSA after adenotonsillectomy. Further research is needed to understand the effects of various social capital measures on pediatric OSA and adenotonsillectomy outcomes.

Age modifies the association between severe sleep apnea and all-cause mortality

PurposeWhile sleep apnea (SA) gets more prevalent with advancing age, the impact of age on the association between SA and health outcomes is not well known. We assessed the association between the severity of SA and all-cause mortality in different age groups using large longitudinal data. MethodWe applied a Natural Language Processing pipeline to extract the apnea-hypopnea index (AHI) from the physicians’ interpretation of sleep studies performed at the Veteran Health Administration (FY 1999–2022). We categorized the participants as no SA (n-SA, AHI< 5) and severe SA (s-SA, AHI≥30). We grouped the cohort based on age: Young≤40; Middle-aged:40–65; and Older adults≥65; and calculated the odds ratio (aOR) of mortality adjusted for age, sex, race, ethnicity, BMI, and Charlson-Comorbidity Index (CCI) using n-SA as the reference. ResultsWe identified 146,148 participants (age 52.23 ± 15.02; BMI 32.11 ± 6.05; male 86.7 %; White 66 %). Prevalence of s-SA increased with age. All-cause mortality was lower in s-SA compared to n-SA in the entire cohort (aOR,0.56; 95%CI: 0.54,0.58). Comparing s-SA to n-SA, the all-cause mortality rates (Young 1.86 % vs 1.49 %; Middle-aged 12.07 % vs 13.34 %; and Older adults 26.35 % vs 40.18 %) and the aOR diminished as the age increased (Young: 1.11, 95%CI: 0.93–1.32; Middle-aged: 0.64, 95%CI: 0.61–0.67; and Older adults: 0.44, 95%CI: 0.41–0.46). ConclusionThe prevalence of severe SA increased while the odds of all-cause mortality compared to n-SA diminished with age. SA may exert less harmful effects on the aged population. A causality analysis is warranted to assess the relationship between SA, aging, and all-cause mortality.

Association between obstructive sleep apnea (OSA) and COVID-19 severity.

Obstructive sleep apnea and sleep-related hypoxia have been associated with higher rates of hospitalization and mortality among patients with Coronavirus disease 2019 (COVID-19). We further explored the association between obstructive sleep apnea, COVID-19 severity and related mortality. In addition, we examined the effects of clinical and demographic parameters on COVID-19. In this retrospective study, we included adult patients who were diagnosed with COVID-19 prior to the Omicron variant identification. We compared the severity of COVID-19 and mortality with the diagnosis of obstructive sleep apnea. The study population included 44,275 patients who tested positive for COVID-19. Of these, 97% had mild or asymptomatic disease, 1.2% had moderate disease, and 1.8% had severe disease. Obstructive sleep apnea was diagnosed in 980 (2.2%) patients. In a multivariate analysis, obstructive sleep apnea diagnosis increased the risk of severe COVID-19 by 1.6 (95% confidence interval: 1.1-2.4) compared with mild disease. However, no increase in mortality was associated with obstructive sleep apnea. Interestingly, patients with moderate and high socioeconomic status had a 1.6 times higher risk for severe COVID-19 than patients from the low socioeconomic status group (95% confidence interval: 1.2-2.1 and 95% confidence interval: 1.1-2.3, respectively). The risk of dying due to COVID-19 was 1.6 (95% confidence interval: 1.1-2.5) and 3.1 (95% confidence interval: 1.8-5.3) times higher in patients with medium and high socioeconomic status, respectively, compared with patients with low socioeconomic status. Diagnosis of obstructive sleep apnea was found to be an independent risk factor for severe COVID-19. The higher the socioeconomic status, the higher the risk of severe COVID-19 morbidity and mortality.

Revealing inconsistencies between Epworth scores and apnea-hypopnea index when evaluating obstructive sleep apnea severity: a clinical retrospective chart review.

A common practice in clinical settings is the use of the Epworth Sleepiness Scale (ESS) and apnea-hypopnea index (AHI) to demonstrate the severity of obstructive sleep apnea (OSA). However, several instances were noted where there were discrepancies in the reported severity between Epworth scores and AHI in our patient sample, prompting an investigation into whether OSA severity as demonstrated by AHI or predicted by ESS quantification of sleepiness is primarily responsible for inconsistencies. Discrepancies were examined between Epworth scores and AHI by categorizing patients into two categories of inconsistency: individuals with either ESS < 10 and AHI ≥ 15 events/h or ESS ≥ 10 and AHI < 15 events/h. The potential influence of sex on these categories was addressed by assessing whether a significant difference was present between mean Epworth scores and AHI values for men and women in the sample. We investigated BMI both by itself as its own respective variable and with respect to the sex of the individuals, along with a consideration into the role of anxiety. Furthermore, we tested anxiety with respect to sex. In the first category of inconsistency the average ESS of 5.27 ± 0.33 suggests a normal level of daytime sleepiness. However, this contrasts with the average AHI of 32.26 ± 1.82 events/h which is indicative of severe OSA. In the second category the average ESS of 14.29 ± 0.47 suggests severe daytime sleepiness, contradicting the average AHI of 9.16 ± 0.44 events/h which only indicates mild OSA. Sex, BMI (both as a variable by itself and with respect to sex), and anxiety (both as a variable by itself and with respect to sex) contributed to observed inconsistencies. The findings of our study substantiate our hypothesis that Epworth scores should be de-emphasized in the assessment of OSA and a greater importance should be placed on measures like AHI. While Epworth scores offer insights into patients' daytime sleepiness levels and the perceived severity of their OSA, the inconsistencies highlighted in our results when compared to AHI-based OSA severity underscore their potential inaccuracy. Caution is advised when utilizing Epworth scores for evaluating OSA severity in clinical settings.

The role of serum C-Fos and glial fibriller acidic protein levels in detecting the severity of obstructive sleep apnea.

Hypoxia and sleep fragmentations that develop during sleep cause central nervous system damage in patients with obstructive sleep apnea (OSA). This study investigates the relationship between OSA severity and glial fibrillary acidic protein (GFAP) and c-Fos, which are considered indicators of neuronal damage. The study included 84 participants (70 patients with OSA and 14 healthy individuals). All participants were evaluated with the Epworth Sleepiness Scale (ESS) before polysomnography (PSG), and serum GFAP and c-Fos values were measured after PSG. All participants were grouped according to the apnea-hypopnea index (AHI) score (control: AHI < 5, Mild OSA: 5 ≤ AHI < 15; moderate OSA: 15 ≤ AHI < 30; severe OSA: AHI ≥ 30). The average age of the participants was 48.5 ± 11.4 years. According to AHI scoring, 14 healthy individuals (16.7%) were in the control group, and 70 patients (83.3%) were in OSA groups. The serum GFAP levels and c-Fos levels were increased in the OSA groups (7.1 ± 5.7 ng/mL and 7.9 ± 7.5 pg/mL respectively) compared to the control group (1.3 ± 0.4 ng/mL and 2.7 ± 1.4 pg/mL p < 0.001 and p < 0.01, respectively). There was a significant positive correlation between AHI and oxygen desaturation index (ODI) values, which indicate disease severity, and serum c-Fos (r: 0.381 and r:0.931, p < 0.01, respectively) and GFAP (r: 0.793 and r:0.745, p < 0.01, respectively) values. Serum GFAP and c-Fos values, which are considered indicators of neuronal damage, can be used as a serum marker to determine disease severity in OSA.

Prevalence, Severity, and Treatment of Obstructive Sleep Apnea in Children with Down Syndrome in Qatar.

Patients with Down syndrome (DS) are at risk for sleep disorder breathing (SDB) due to their abnormal craniofacial anatomy, hypotonia, and propensity for obesity. The prevalence and severity of SDB in this population vary between different cohorts due to the multifactorial nature of these patients and the different diagnostic criteria used. We aim to report the prevalence and severity of SDB in the DS population in Qatar. This study is a retrospective review of all patients with genetically confirmed DS who completed a diagnostic polysomnography (PSG) study at Sidra Medicine in Doha, Qatar, which is the only pediatric sleep center in the country, between September 2019 and July 2022. Clinical and PSG data were collected from the patients' electronic medical records. Central and obstructive events were scored according to the American Academy of Sleep Medicine (AASM) criteria. Obstructive sleep apnea (OSA) diagnosis was made based on apnea-hypopnea index (AHI) and defined as AHI>1.5 events/hour.OSA was considered mild if AHI was ≥ 1.5 but < 5, moderate if AHI was ≥ 5 but < 10, and severe if AHI was ≥ 10 events/hour. Diagnosis with central apnea was considered if the central apnea index was > 5 events/hour. Hypoventilation was considered present if end-tidal/transcutaneous carbon dioxide gas was more than 50 mmHg for more than 25% of total sleep time.Multiple regression analysis was performed to evaluate predictors of high AHI and rapid eye movement (REM)-AHI. A total of 80 patients (49 males and 31 females) were included. Median (range) age was 7.3 years (0.9, 21). The mean (range) BMI z-score was 1.7 (-1.3, 4.3). Sixty-five patients were diagnosed with OSA, with a prevalence rate of 81%. OSA was mild in 25 (38.5%) patients, moderate in 15 (23.1%) patients, and severe in 25 (38.5%) patients. Only one patient was diagnosed with central apnea and five patients (6.9%) with alveolar hypoventilation. Multiple regression analysis showed BMI (P = 0.007) and snoring/apnea symptoms (P=0.023) to be predictive of high AHI. No correlation was found between the same variables and REM-AHI. Treatments used for OSA included anti-inflammatory medications in 37 (46%) patients, tonsillectomy/adenoidectomy in 13 (16.5%) patients, and positive airway pressure support in 10 (15%) patients. Our patient population with DS had a high prevalence of OSA comparable to other reported cohorts. High BMI and symptoms of snoring are predictive of OSA.

Effects of acetazolamide on sleep disordered breathing in pulmonary vascular disease: a randomised controlled trial.

Patients with pulmonary vascular disease (PVD) often suffer from nocturnal hypoxaemia, but also from sleep apnoea. Short-term use of acetazolamide increases ventilation due to metabolic acidosis and also reduces loop gain. We investigated whether prolonged use of acetazolamide improves sleep disordered breathing in PVD. In a randomised controlled crossover trial, patients with PVD were randomly assigned to acetazolamide 250 mg and placebo twice daily for 5 weeks. Patients underwent respiratory polygraphy at baseline and at the end of each intervention phase. Outcomes of interest were the effect of acetazolamide on mean nocturnal oxygen saturation (S pO2 ), time with oxygen saturation <90% (t <90), apnoea-hypopnoea index (AHI) and sleep apnoea severity. In 20 patients with PVD (55% women, nine with pulmonary arterial hypertension, 11 with distal chronic thromboembolic pulmonary hypertension; mean±sd nocturnal S pO2 88.8±3.5%, obstructive AHI 12.6±12.3 events·h-1), 5 weeks of acetazolamide resulted in a significant improvement in nocturnal oxygenation compared to placebo (mean nocturnal S pO2 +2.3% (95% CI 1.3-3.3%); p<0.001 and t <90 -18.8% (95% CI -29.6- -8.0%); p=0.001). Acetazolamide increased the proportion of patients with mean nocturnal S pO2 ≥90% from 45% to 85%. The percentage of patients with AHI >5 events·h-1 was reduced from 75% to 60% and with AHI >15 events·h-1 from 30% to 15%. Two patients discontinued the study because of mild side-effects. Acetazolamide given for 5 weeks reduces nocturnal hypoxaemia in PVD to a clinically relevant level and reduces the proportion of patients with obstructive sleep apnoea.

The Correlation between the Severity of Obstructive Sleep Apnea and Insulin Resistance in a Japanese Population.

Background: Repetitive episodes of apnea and hypopnea during sleep in patients with obstructive sleep apnea (OSA) are known to increase the risk of atherosclerosis. Underlying obesity and related disorders, such as insulin resistance, are indirectly related to the development of atherosclerosis. In addition, OSA is independently associated with insulin resistance; however, data regarding this relationship are scarce in Japanese populations. Methods: This study aimed to examine the relationship between the severity of OSA and insulin resistance in a Japanese population. We analyzed the data of consecutive patients who were referred for polysomnography under clinical suspicion of developing OSA and who did not have diabetes mellitus or any cardiovascular disease. Multiple regression analyses were performed to determine the relationship between the severity of OSA and insulin resistance. Results: The data from a total of 483 consecutive patients were analyzed. The median apnea-hypopnea index (AHI) was 40.9/h (interquartile range: 26.5, 59.1) and the median homeostasis model assessment for insulin resistance (HOMA-IR) was 2.00 (interquartile range: 1.25, 3.50). Multiple regression analyses revealed that the AHI, the lowest oxyhemoglobin saturation (SO2), and the percentage of time spent on SO2 < 90% were independently correlated with HOMA-IR (an adjusted R-squared value of 0.01278821, p = 0.014; an adjusted R-squared value of -0.01481952, p = 0.009; and an adjusted R-squared value of 0.018456581, p = 0.003, respectively). Conclusions: The severity of OSA is associated with insulin resistance assessed by HOMA-IR in a Japanese population.