Effect of CPAP on blood pressure in patients with minimally symptomatic obstructive sleep apnoea: a meta-analysis using individual patient data from four randomised controlled trials

The interrelationships between sleep regularity, obstructive sleep apnea, and hypertension in a middle-aged community population

STUDY OBJECTIVES

Little is known about the interrelationships between sleep regularity, obstructive sleep apnea (OSA) and important health markers. This study examined whether irregular sleep is associated with OSA and hypertension, and if this modifies the known association between OSA and hypertension.

METHODS

Six hundred and two adults (age mean(SD) = 56.96(5.51) years, female = 60%) from the Raine Study who were not evening or night shift workers were assessed for OSA (in-laboratory polysomnography; apnea-hypopnea index ≥ 15 events/hour), hypertension (doctor diagnosed, or systolic blood pressure ≥140 mmHg and/or diastolic ≥90 mmHg) and sleep (wrist actigraphy for ≥5 days). A sleep regularity index (SRI) was determined from actigraphy. Participants were categorized by tertiles as severely irregular, mildly irregular, or regular sleepers. Logistic regression models examined the interrelationships between SRI, OSA and hypertension. Covariates included age, sex, body mass index, actigraphy sleep duration, insomnia, depression, activity, alcohol, smoking, and antihypertensive medication.

RESULTS

Compared to regular sleepers, participants with mildly irregular (OR 1.97, 95% confidence intervals [CI] 1.20 to 3.27) and severely irregular (OR 2.06, 95% CI: 1.25 to 3.42) sleep had greater odds of OSA. Compared to those with no OSA and regular sleep, OSA and severely irregular sleep combined had the highest odds of hypertension (OR 2.34 95% CI: 1.07 to 5.12; p for interaction = 0.02) while those with OSA and regular/mildly irregular sleep were not at increased risk (p for interaction = 0.20).

CONCLUSIONS

Sleep irregularity may be an important modifiable target for hypertension among those with OSA.

A retrospective evaluation of patients with sleep breathing disorders in single center, Edirne province

Introduction

Our aim was to investigate the characteristics of patients with preliminary diagnosis of sleep breathing disorder studied in Edirne province, to identify the risk factors and comorbid conditions, to determine the diagnostic distribution of our sleep patients by analyzing the results of polysomnography and PAP titration, and to understand their problems related to treatment compliance and device use.

Materials and Methods

Our study retrospectively evaluated the results of 956 patients who had sleep-related complaints in our region and underwent full nocturnal polysomnography and PAP titration with a preliminary diagnosis of sleep breathing disorder.

Results

A total of 956 patients were enrolled in the study, of whom 641 (67.1%) were males and 315 (32.9%) were females. Of our patients, 49.7% had severe obstructive sleep apnea (OSA), 18.2% had moderate OSA, 17.9% had mild OSA, 11.4% had REM-dependent OSA, and 8.4% had positionsupine-dependent OSA. Hypertension was the most common comorbid condition in 44% of our patients, and diabetes mellitus in 25%. It was determined that 228 (57.9%) of 394 patients who were recommended to use the PAP device received the device, and 71.5% of these patients could use the device in a compatible manner.

Conclusion

Patients with appropriate symptoms can be diagnosed with a high probability of OSA in our region. The fact that a substantial group of patients diagnosed with OSA and recommended to use the PAP device did not receive the device or the proportion of those who could not use the device was high is one of the notable findings of the study.

Effect of positive airway pressure compliance on laryngopharyngeal reflux in obstructive sleep apnea patients

OBJECTIVES

To determine the effect of continuous positive airway pressure (CPAP) compliance on symptoms and signs of laryngopharyngeal reflux (LPR) in patients with obstructive sleep apnea (OSA).

RESULTS

Thirty patients were included. The participants were divided into good compliance (n = 21) and poor compliance (n = 9) groups. After 6-month CPAP treatment, the reflux symptom index score significantly decreased in both the good compliance group (20 (17,24) vs. 14 (10,18), p < 0.001) and the poor compliance group (21 (18,25) vs. 10 (5,16), p < 0.05). Reflux finding score was significantly reduced in both the good compliance group (8 (6,9) vs. 4 (3,5), p < 0.001) and the poor compliance group (6 (4,8) vs. 3 (2,4), p < 0.05). However, there were no statistically significant differences between the groups. CPAP treatment reduces the symptoms and signs of LPR. However, CPAP compliance does not correlate with improvement in LPR in patients with OSA.

Remote Monitoring of Positive Airway Pressure Data: Challenges, Pitfalls, and Strategies to Consider for Optimal Data Science Applications

Over recent years, positive airway pressure (PAP) remote monitoring has transformed the management of OSA and produced a large amount of data. Accumulated PAP data provide valuable and objective information regarding patient treatment adherence and efficiency. However, the majority of studies that have analyzed longitudinal PAP remote monitoring have summarized data trajectories in static and simplistic metrics for PAP adherence and the residual apnea-hypopnea index by the use of mean or median values. The aims of this article are to suggest directions for improving data cleaning and processing and to address major concerns for the following data science applications: (1) conditions for residual apnea-hypopnea index reliability, (2) lack of standardization of indicators provided by different PAP models, (3) missing values, and (4) consideration of treatment interruptions. To allow fair comparison among studies and to avoid biases in computation, PAP data processing and management should be conducted rigorously with these points in mind. PAP remote monitoring data contain a wealth of information that currently is underused in the field of sleep research. Improving the quality and standardizing data handling could facilitate data sharing among specialists worldwide and enable artificial intelligence strategies to be applied in the field of sleep apnea.

The individual and societal price of non-adherence to continuous positive airway pressure, contributors and strategies for improvement

INTRODUCTION

Continuous positive airway pressure (CPAP) is the first line therapy for obstructive sleep apnea (OSA). CPAP is highly effective for improving symptoms and quality of life but the major issue is adherence, with up to 50% of OSA discontinuing CPAP in the first 3 years after CPAP initiation.

AREAS COVERED

We present the individual and societal cost of non-adherence to CPAP, factors associated with non-adherence to CPAP, as well as current strategies for improving adherence including telehealth, couples-based interventions and behavioral interventions. We also report on challenges and pitfalls for the visualization and analysis of CPAP remote monitoring platforms.

EXPERT OPINION

CPAP termination rates and adherence to therapy remain major issues despite technical improvements in CPAP devices. The individual and societal price of non-adherence to CPAP for OSA patients goes beyond excessive sleepiness and includes cardiovascular events, all-cause mortality, and increased health costs. Strategies for improving CPAP adherence should be individually tailored and aim to also improve lifestyle habits including physical activity and nutrition. Access to these strategies should be supported by refining visualization dashboards of CPAP remote monitoring platforms, and by disseminating telehealth and innovative analytics, including artificial intelligence.

The effect of CPAP therapy on heart rate variability in patients with obstructive sleep apnea

The aim of this study was to analyze the relationship between the initiation of CPAP therapy and HRV in patients with OSA. The study group consisted of 37 patients, aged 34-79 (mean 54.95 years) with OSA treated with CPAP. Two subgroups of patients were distinguished: less than severe (AHI < 30, n = 16) and severe OSA (AHI ≥ 30, n = 21). The second study was carried out around a month after the initiation of therapy. CPAP therapy caused the improvement in polysomnographic parameters, however, in most parameters in time and frequency analysis, there were no significant positive changes in parasympathetic tone. Moreover, in HRV time analysis, the reduced rMSSD and pNN50 parameters in the hours of night rest and rMSSD and SDSD during the 15-min N3 sleep period were noted. Especially, in the group with AHI ≥ 30, we observed significant decreases in rMSSD and pNN50 for the entire time. The changes were mainly for the night periods including the N3 sleep period, which is especially connected with sleep apnea (parameters: rMSSD, SDSD, and pNN50). In spectral analysis, the decrease in HF from the 15-min daily activity period and the N3 sleep period was observed. Inverse correlations were seen between the maximum, median, and mean positive airway pressure (PAP) and the change in rMSSD, SDNN, and SDSD, mainly during night hours and the N3 sleep period. Only in patients with AHI < 30 the increase in SDNN was observed in 15-min N3 sleep period. The beneficial increase in SDNN parameter from time analysis was observed only in one sleep period in less ill patients with OSA. The lack of significant changes was observed in the majority of the parameters of heart rate variability after initiation of CPAP therapy in a short observational time; however, the shift towards reduced HRV was observed in patients with AHI > 30, so the response to CPAP therapy may depends on the severity of the apnea. The results may suggest that a longer observational period is needed in such studies, and the problem is still not fully elucidated.

Clinical application of headache impact test (HIT)-6 and epworth sleepiness scale (ESS) for sleep apnea headache

Background

Sleep apnea headache is a major symptom accompanying obstructive sleep apnea (OSA), but relatively little evidence has been reported on the magnitude of its negative effects on patients or the evaluation of therapeutic effects. We quantitatively assessed sleep apnea headache using the Epworth sleepiness scale (ESS) and headache impact test (HIT)-6.

Methods

The first part of this study enrolled 86 patients (72 male; mean [± standard deviation] age 53.2 ± 13.8 years) who had been diagnosed with OSA by polysomnography in our sleep center and investigated the prevalence and characteristics of sleep apnea headache. The second part enrolled 21 patients (12 male; mean age, 47.5 ± 13.0 years) diagnosed with sleep apnea headache by polysomnography and/or peripheral arterial tonometry and evaluated the effects of OSA therapy on headache. Medical records including ESS, HIT-6, and polysomnographic data were retrospectively analyzed.

Results

The prevalence of sleep apnea headache among OSA patients was 22.1%, and was higher in female (50.0%) than in male (16.7%). The proportion of N3 and HIT-6 score showed a significant negative correlation (Pearson’s R = -0.51, p < 0.05). In female, median apnea–hypopnea index (AHI) was significantly lower in patients with headache (26.1 /h [interquartile range 21.4–29.6 /h]) than in patients without (54.2 /h [41.3–73.9 /h], p < 0.05, Wilcoxon rank-sum test). HIT-6 and ESS scores improved from 56.4 ± 9.7 to 45.9 ± 8.4 and from 9.0 ± 4.4 to 5.3 ± 4.2 in patients with oral appliance (OA), and from 54.3 ± 10.7 to 44.6 ± 6.1 and from 10.0 ± 4.0 to 4.9 ± 2.9 with continuous positive airway pressure (CPAP). In patients with good CPAP adherence, these scores improved from 58.1 ± 10.8 to 44.0 ± 6.0 and from 9.6 ± 3.8 to 3.6 ± 1.7.

Conclusion

Among patients with OSA, prevalence of sleep apnea headache was higher in female than in male. In female, headache was associated with relatively mild OSA. OA showed substantial effects on headache in mild to moderate OSA patients. CPAP adherence was important for improving the headache. HIT-6 score appears useful for the diagnosis and management of sleep apnea headache.

Comparison of CPAP and Expansion Sphincter Pharyngoplasty using the Mean Disease Alleviation Concept

OBJECTIVE

Continuous Positive Airway Pressure (CPAP) is the typical first treatment for Obstructive Sleep Apnea (OSA); however, patient adherence is often suboptimal. Expansion Sphincter Pharyngoplasty (ESP) is an alternative treatment option for patients with OSA who demonstrate signs of palatal and lateral pharyngeal collapse. The aim of this study is to compare therapeutic outcomes, using the mean disease alleviation concept, for patients who underwent ESP to patients undergoing CPAP therapy.

DATA SOURCES

Single-institution retrospective cohort study.

METHODS

All patients who underwent ESP from 2018 to 2021 or were prescribed CPAP from December to June 2021 at our institution were assessed for inclusion. ESP patients who had pre- and post-operative sleep studies available and CPAP patients who followed up at our institution's sleep clinic were included for analysis. Charts were reviewed for demographic information and sleep study results, and treatment outcomes were measured by calculating mean disease alleviation.

RESULTS

There were 77 patients in the ESP group and 107 patients in the CPAP group. AHI reduction was greater in the CPAP group (p = 0.016); however, mean disease alleviation was similar between groups (p = 0.076). One-way ANCOVA demonstrated similar MDA between groups when controlling for patient age, BMI, gender, and pre-operative AHI (F [1,177] = 2,931.6, p = 0.104).

CONCLUSION

CPAP therapy provided superior reduction in AHI compared to ESP; however, overall treatment efficacy as measured by mean disease alleviation was similar for both groups.

LEVEL OF EVIDENCE

3 Laryngoscope, 2023.

Single-Night Diagnosis of Sleep Apnea Contributes to Inconsistent Cardiovascular Outcome Findings

BACKGROUND

Single-night disease misclassification of OSA due to night-to-night variability may contribute to inconsistent findings in OSA trials.

RESEARCH QUESTION

Does multinight quantification of OSA severity provide more precise estimates of associations with incident hypertension?

STUDY DESIGN AND METHODS

A total of 3,831 participants without hypertension at baseline were included in simulation analyses. Included participants had ≥ 28 days of nightly apnea-hypopnea index (AHI) recordings via an under-mattress sensor and ≥ 3 separate BP measurements over a 3-month baseline period followed by ≥ 3 separate BP measurements 6 to 9 months postbaseline. Incident hypertension was defined as a mean systolic BP ≥ 140 mm Hg or a mean diastolic BP ≥ 90 mm Hg. Simulated trials (1,000) were performed, using bootstrap methods to investigate the effect of variable numbers of nights (x = 1-56 per participant) to quantify AHI and the ability to detect associations between OSA and incident hypertension via logistic regression adjusted for age, sex, and BMI.

RESULTS

Participants were middle-aged (mean ± SD, 52 ± 12 y), mostly men (91%), and overweight (BMI, 28 ± 5 kg/m²). Single-night quantification of OSA failed to detect an association with hypertension risk in 42% of simulated trials (α = 0.05). Conversely, 100% of trials detected an association when AHI was quantified over ≥ 28 nights. Point estimates of hypertension risk were also 50% higher and uncertainty was 5 times lower during multinight vs single-night simulation trials.

INTERPRETATION

Multinight monitoring of OSA allows for better estimates of hypertension risk and potentially other adverse health outcomes associated with OSA. These findings have important implications for clinical care and OSA trial design.

Should we treat with continuous positive airway pressure severe non-sleepy obstructive sleep apnea individuals without underlying cardiovascular disease?

The majority of the current international obstructive sleep apnea (OSA) guidelines base the recommendation to treat OSA with continuous positive airway pressure (CPAP) on the presence of symptoms (principally, albeit not exclusively on daytime hypersomnolence). In nonsleepy patients, even with severe OSA, controversies remain, as clear evidence supporting CPAP treatment of this subgroup of OSA patients is lacking. However, given the nonnegligible proportion of non-sleepy OSA patients, clinicians often face a serious dilemma since CPAP treatment in these patients may prove to be not cost-effective. Here, we propose a simple three-step-based algorithm that attempts to better phenotype non-sleepy OSA patients prior to reaching a CPAP treatment decision while also considering a series of clinically relevant elements in the process that may improve with CPAP therapy. Such algorithm focuses on the presence of several OSA symptoms that are susceptible to benefit from treatment and also relies on OSA phenotypes that need to be considered in an effort to achieve optimal cardiovascular prevention. Here, we attempt to establish a framework for clinicians who are evaluating severe nonsleepy OSA patients in their practices. However, the algorithm proposal needs to be extensively validated before being systematically implemented in clinical settings.

Sleep-disordered Breathing in Pregnancy and after Delivery: Associations with Cardiometabolic Health

Rationale: Knowledge gaps exist regarding health implications of sleep-disordered breathing (SDB) identified in pregnancy and/or after delivery. Objectives: To determine whether SDB in pregnancy and/or after delivery is associated with hypertension (HTN) and metabolic syndrome (MS). Methods: nuMoM2b-HHS (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be Heart Health Study) (N = 4,508) followed participants initially recruited during their first pregnancy. Participants returned for a visit 2-7 years after pregnancy. This study examined a subgroup who underwent SDB assessments during their first pregnancy (n = 1,964) and a repeat SDB assessment after delivery (n = 1,222). Two SDB definitions were considered: 1) apnea-hypopnea index (AHI) ⩾ 5 and 2) oxygen desaturation index (ODI) ⩾ 5. Associations between SDB and incident HTN and MS were evaluated with adjusted risk ratios (aRRs). Measurements and Main Results: The aRR for MS given an AHI ⩾ 5 during pregnancy was 1.44 (95% confidence interval [CI], 1.08-1.93), but no association with HTN was found. ODI ⩾ 5 in pregnancy was associated with both an increased risk for HTN (aRR, 2.02; 95% CI, 1.30-3.14) and MS (aRR, 1.53; 95% CI, 1.19-1.97). Participants with an AHI ⩾ 5 in pregnancy that persisted after delivery were at higher risk for both HTN (aRR, 3.77; 95% CI, 1.84-7.73) and MS (aRR, 2.46; 95% CI, 1.59-3.76). Similar associations were observed for persistent ODI ⩾ 5 after delivery. Conclusions: An AHI ⩾ 5 in pregnancy was associated with an increased risk of MS. An ODI ⩾ 5 in pregnancy was significantly associated with both HTN and MS. Participants with persistent elevations in AHI and ODI during pregnancy and at 2-7 years after delivery were at the highest risk for HTN and MS. Clinical trial registered with www.clinicaltrials.gov (NCT02231398).

Long-term Effect of OSA and CPAP Treatment on Blood Pressure in Patients with Acute Coronary Syndrome

RATIONALE

Obstructive sleep apnea (OSA) is prevalent in acute coronary syndrome (ACS) patients and is a cause of secondary hypertension.

OBJECTIVE

To explore the long-term effects of OSA and CPAP treatment on blood pressure (BP) in ACS patients.

METHODS

Post-hoc analysis of the ISAACC study included 1803 patients admitted for ACS (NCT01335087). Patients with OSA (apnea-hypopnea index (AHI) ≥15 events/h) were randomly assigned to receive either CPAP or/and usual care and followed up for one to 5 years. Office BP was determined at each visit.

RESULTS

We included 596 patients without OSA, 978 patients in the usual care/poor CPAP adherence group and 229 patients in the good CPAP adherence group. At baseline, 52% of the patients were diagnosed with hypertension. Median age and body mass index were 59 [52.0;67.0] years and 28.2 [25.6;31.2] kg/m2, respectively. After a median [25th;75th percentile] follow-up of 41.2 [18.3;59.6] months, BP changes were similar between OSA and non-OSA groups. However, we observed an increase in BP in the third tertile of the AHI (AHI>40 events/h) with a maximum difference in mean BP of +3.3 mmHg at 30 months. OSA patients with good CPAP adherence (≥4 hours/night) reduced mean BP after 18 months compared to usual care/poor CPAP adherence patients, maximum mean difference (95% CI) of -4.7 (-6.7,-2.7) mmHg. In patients with severe OSA we observed a maximum mean difference of -7.1 (-10.3,-3.8) mmHg.

CONCLUSIONS

In patients with ACS, severe OSA is associated with a long-term increase in BP, which is reduced by good CPAP adherence.

Influence of Apnea Hypopnea Index and the Degree of Airflow Limitation on Endothelial Function in Patients Undergoing Diagnostic Coronary Angiography

Background: Obstructive sleep apnea is associated with an increased prevalence of cardiovascular disease. The mechanism of these associations is not completely understood. We aimed to investigate the association of the apnea hypopnea index and the degree of airflow limitation with endothelial dysfunction. Methods: This was a single-center prospective study of patients admitted for diagnostic coronary angiography (CAG). Endothelial function was assessed by the non-invasive EndoPAT system by reactive hyperemia index (RHI) and divided into two groups: endothelial dysfunction and normal endothelial function. Sleep apnea signs were detected by WatchPAT measuring the respiratory disturbance index (pRDI), the apnea and hypopnea index (pAHI), and the oxygen desaturation index (ODI). Patients underwent spirometry and body plethysmography. Based on CAG, the severity of coronary artery disease was assessed as follows: no significant coronary artery disease, single-, two- and three-vessel disease. Results: A total of 113 patients were included in the study. Breathing disorders measured by WatchPAT and spirometry were more severe in patients with endothelial dysfunction: pRDI (27.3 vs. 14.8, p = 0.001), pAHI (24.6 vs. 10.3, p < 0.001), ODI (13.7 vs. 5.2, p = 0.002), forced expiratory volume in one second (FEV1) (81.2 vs. 89, p = 0.05). In a multivariate regression analysis, pAHI and FEV1 were independent predictors of endothelial dysfunction assessed by RHI. There was no correlation between the severity of coronary artery disease and endothelial dysfunction. Conclusions: Obstructive sleep apnea signs and greater airflow limitation were associated with endothelial dysfunction regardless of the severity of the coronary artery disease.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared in order to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Because sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep-disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Since sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

Effect of CPAP treatment on BP in resistant hypertensive patients according to the BP dipping pattern and the presence of nocturnal hypertension

High heterogeneity in the blood pressure (BP) response to continuous positive airway pressure (CPAP) exists in patients with resistant hypertension (RH). Only nondipper normotensive and hypertensive patients exhibited BP reductions when treated with CPAP; the baseline BP dipping pattern has been proposed as a predictor of BP response to CPAP but has never been explored in patients with RH. This study aimed to assess the effect of CPAP on BP in subjects with RH with respect to BP dipping pattern or nocturnal hypertension. This is an ancillary study of the SARAH study. RH subjects with an apnea/hypopnea index (AHI) ≥ 15/h and who received CPAP treatment for 1 year were included. Subjects underwent a sleep study and ambulatory BP monitoring (ABPM) at baseline and at the 1-year follow-up. Eighty-nine RH subjects were included. The subjects were mainly male (77.5%) and obese, with a mean age of 66 years (25th-75th percentile; 59.0; 70.0) and an AHI of 32.7/h (25th-75th percentile; 25.0; 54.7). A total of 68.5% of participants were nondippers, and 71.9% had nocturnal hypertension. After 1 year of CPAP, no significant differences in ABPM parameters were observed between dippers and nondippers. According to nighttime BP, subjects with nocturnal normotension did not show significant changes in ABPM parameters, while nocturnal hypertensive subjects achieved a significant reduction in mean nighttime BP of -4.38 mmHg (-7.10 to -1.66). The adjusted difference between groups was 3.04 (-2.25 to 8.34), which was not significant. This study shows that the BP response to CPAP in patients with RH does not differ according to the BP dipping pattern (dipper and nondipper) and suggests a differential response according to the presence of nocturnal hypertension (ClinicalTrials.gov: NCT03002558).

Effect of adenotonsillectomy on blood pressure in children with obstructive sleep apnea: a meta-analysis

BACKGROUND

While adenotonsillectomy (T&A) is widely recognized as the first-line therapy for pediatric obstructive sleep apnea (OSA), effects of T&A on blood pressure (BP) remain unclear. This meta-analysis evaluates the associations between T&A and BP in children with OSA.

METHODS

The study protocol was registered on PROSPERO (CRD42020154425). Two authors independently searched the PubMed, Medline, EMBASE, and Cochrane databases. The keywords used were "sleep apnea syndromes," "adenotonsillectomy," and "child." A random-effects model was applied to determine office systolic BP (SBP), diastolic BP (DBP), and ambulatory BP changes.

RESULT

Twelve studies with 1193 children were analyzed (mean age: 7.6 y; 54% boys). The apnea-hypopnea index significantly reduced of 9.4 events/h (95% CI, -12.0 to -6.8) after T&A. Office SBP (-0.24 mmHg; 95% CI, -1.64 to 1.16) and DBP (-1.65 mmHg; 95% CI, -3.47 to 0.17) did not decrease significantly after surgery. No significant decreases were observed in 24-h ambulatory BP after T&A. Subgroup analysis showed a significant postoperative decrease in office SBP (-6.23 mmHg; 95% CI, -7.78 to -4.67) and DBP (-7.93 mmHg; 95% CI, -10.37 to -5.48) among children with hypertension but a slight increase in office SBP (2.50 mmHg; 95% CI, 1.14 to 3.86) and DBP (1.98 mmHg; 95% CI, -0.02 to 3.98) in those without (P for heterogeneity < 0.001).

CONCLUSION

This meta-analysis suggests the office and ambulatory BP changes after T&A in children with OSA are trivial. Moreover, children with hypertension experience a significantly greater decrease in office BP than children without hypertension.

Socioeconomic Factors and Adherence to CPAP: The Population-Based Course of Disease in Patients Reported to the Swedish CPAP Oxygen and Ventilator Registry Study

Background

Early identification of poor adherence to CPAP treatment is of major clinical importance to optimize treatment outcomes in patients with OSA.

Research Question

How do socioeconomic factors influence CPAP adherence?

Study Design and Methods

Nationwide, population-based cohort study of patients with OSA receiving CPAP treatment reported to the Swedish quality registry Swedevox between 2010 and 2018 was cross-linked with individual socioeconomic data from Statistics Sweden. Socioeconomic factors associated with CPAP adherence were identified using a multivariate linear regression model, adjusted for age and sex.

Results

In total, 20,521 patients were included: 70.7% men; mean age ± SD, 57.8 ± 12.2 years; BMI, 32.0 ± 6.1 kg/m²; apnea-hypopnea index, 36.9 ± 22.1; Epworth Sleepiness Scale, 10.4 ± 5.0; and median nocturnal CPAP use, 355 min (interquartile range, 240-420 min). Adherence after 1.3 ± 0.8 years of CPAP use was significantly (all P < .001) associated with civil status (married vs unmarried: +20.5 min/night), education level (high, ≥ 13 years vs low, ≤ 9 years: +13.2 min/night), total household income (highest/third/second vs lowest quartile: +15.9 min/night, +10.4 min/night, and +6.1 min/night, respectively), and country of birth (born in Sweden with one native parent/born in Sweden with two native parents vs being born abroad: +29.0 min/night and +29.3 min/night, respectively).

Interpretation

Civil status, educational level, household income, and foreign background predict CPAP adherence in a clinically significant manner and should be considered when treating OSA with CPAP.

Determinants of usage and non-adherence to noninvasive ventilation in children and adults with Duchenne muscular dystrophy

STUDY OBJECTIVES

Duchenne muscular dystrophy (DMD) is a neuromuscular disorder that leads to chronic respiratory insufficiency and failure. Use of home noninvasive ventilation (NIV) has been linked to improved outcomes including reduced mortality. Despite the importance of NIV, factors promoting optimal NIV usage and determinants of non-adherence have not been rigorously examined. Moreover, given that respiratory issues in DMD span between childhood and adulthood, examination across a broad age group is needed. The objectives of this study were to (1) evaluate NIV usage across a broad spectrum of DMD patients including both children and adults; and (2) identify biological and socioeconomic determinants of NIV usage and NIV non-adherence.

METHODS

We performed a retrospective review of all DMD patients from Feb 2016 to Feb 2020 who underwent evaluation at associated pediatric and adult neuromuscular disease clinics. NIV use was determined objectively from device downloads. A priori, we defined non-adherence as <4 hours use per night, quantified as the percentage of nights below this threshold across a 30-day period within 6 months of a clinic visit. We also assessed the average hours of NIV usage over this time period. Predictors examined included demographics, social determinants, and pulmonary function.

RESULTS

33 patients with DMD were identified, 29 (87%) of whom were using NIV (13 age < 21 years). Mean age was 22.9±6.6 years (range 13-39 years), BMI was 23.4±10.4 kg/m², and seated forced vital capacity (FVC) was 23%±18% predicted. Mean nightly NIV usage was 7.4±3.8 hours and mean percentage of non-adherent nights was 13%±30%. In univariable analysis, age did not predict use. Those with lower FVC had higher NIV usage hours (p=0.01) and a trend toward less non-adherence (p=0.06). Higher estimated household income demonstrated a trend towards increased usage hours and less non-adherence (both p=0.08). Multivariable analysis found increased usage hours were predicted best by higher income, higher IPAP, and higher bicarbonate. Non-adherence was higher in those with lower income or higher FVC.

CONCLUSIONS

In this cohort of adult and pediatric DMD patients, most individuals were using NIV. While usage hours were higher with lower lung function, substantial variability remains unexplained by examined factors. Non-adherence was observed in some individuals, including those with advanced disease. Further investigations should focus on evaluating patient-oriented outcomes in order to define optimal NIV usage across the spectrum of disease, and determine strategies to counteract issues with non-adherence.

Obstructive Sleep Apnea-Induced Neurogenic Nocturnal Hypertension: A Potential Role of Renal Denervation?

There is a bidirectional, causal relationship between obstructive sleep apnea (OSA) and hypertension. OSA-related hypertension is characterized by high rates of masked hypertension, elevated nighttime blood pressure, a nondipper pattern of nocturnal hypertension, and abnormal blood pressure variability. Hypoxia/hypercapnia-related sympathetic activation is a key pathophysiological mechanism linking the 2 conditions. Intermittent hypoxia also stimulates the renin-angiotensin-aldosterone system to promote hypertension development. The negative and additive cardiovascular effects of OSA and hypertension highlight the importance of effectively managing these conditions, especially when they coexist in the same patient. Continuous positive airway pressure is the gold standard therapy for OSA but its effects on blood pressure are relatively modest. Furthermore, this treatment did not reduce the cardiovascular event rate in nonsleepy patients with OSA in randomized controlled trials. Antihypertensive agents targeting sympathetic pathways or the renin-angiotensin-aldosterone system have theoretical potential in comorbid hypertension and OSA, but current evidence is limited and combination strategies are often required in drug resistant or refractory patients. The key role of sympathetic nervous system activation in the development of hypertension in OSA suggests potential for catheter-based renal sympathetic denervation. Although long-term, randomized controlled trials are needed, available data indicate sustained and relevant reductions in blood pressure in patients with hypertension and OSA after renal denervation, with the potential to also improve respiratory parameters. The combination of lifestyle interventions, optimal pharmacological therapy, continuous positive airway pressure therapy, and perhaps also renal denervation might improve cardiovascular risk in patients with OSA.

What is a Clinically Meaningful Target for Positive Airway Pressure Adherence?

Although good adherence to continuous positive airway pressure (PAP) traditionally is defined as greater than or equal to 4 hours/night, the origins and rationale for this remain unclear. Research studies report variation in optimal duration of PAP adherence, depending on outcome of interest. Evidence demonstrates benefit with PAP for daytime sleepiness, quality of life, neurocognitive outcomes, depression, and hypertension, predominantly in symptomatic, moderate-severe obstructive sleep apnea. Recent randomized controlled trials, however, have failed to demonstrate a reduction in cardiovascular and mortality risks. This review explores the question of what can be considered a clinically meaningful outcome for PAP adherence.

Higher Apnea-Hypopnea Index (AHI) and Oxygen Desaturation Index (ODI) Were Independently Associated with Increased Risks of Hypertension in Patients with T2DM: A Cross-Sectional Study

Objective

The current study aimed to explore the relationship between OSAS and hypertension and whether polysomnography (PSG) indices were independently associated with hypertension in patients with type 2 diabetes (T2DM).

Methods

This study recruited 316 T2DM patients. Multivariable logistic regression analyses were performed to determine the independent association of apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) with hypertension with adjustment for potential confounders.

Results

Among 316 patients, 130 (41.1%) and 204 (64.6%) had hypertension and OSAS, respectively. T2DM patients with hypertension showed significantly increased levels of AHI ((median (interquartile range)): 17.2 (5.7–34.9) vs. 5.7 (2.1–17.3) events/hour, p < 0.001), nonrapid eye movement AHI (NREM-AHI) (17.6 (5.5–36.5) vs. 5.2 (2.2–16.6) events/hour, p < 0.001), ODI (48.4 (21.9–78.0) vs. 22.6 (10.8–48.1) events/hour, p < 0.001), and severities of OSAS and decreased levels of lowest SaO₂ ((mean ± standard deviation): 74.0 ± 10.4 vs. 77.3 ± 9.8, p = 0.004). Multivariable logistic regression analysis showed that higher levels of AHI, NREM-AHI, and ODI were significantly associated with increased risks of hypertension, and the adjusted odds ratios (ORs) with 95% CI were 1.026 (1.008–1.044, p = 0.004), 1.026 (1.009–1.044, p = 0.003), and 1.005 (1.001–1.010, p = 0.040), respectively. Compared with non-OSAS, severe OSAS was significantly associated with the risk of hypertension with the adjusted OR (95% CI) of 3.626 (1.609–8.172, p = 0.002), but associations of rapid eye movement AHI (REM-AHI) and lowest SaO₂ with hypertension were not statistically significant.

Conclusion

Increased AHI, NREM-AHI, ODI, and severities of OSAS were significantly associated with higher risks of hypertension in T2DM patients. Detection and treatment of OSAS are needed to prevent hypertension in T2DM patients.

Characteristics of Obstructive Sleep Apnea Patients With Hypertension and Factors Associated With Autotitration Acceptance

In order to explore the characteristics and treatment status of obstructive sleep apnea (OSA) patients with hypertension, a retrospective study was conducted on 306 patients admitted from October 2018 to December 2019. According to the apnea hypopnea index (AHI), OSA patients with hypertension were divided into three groups. 69 cases were mild OSA (5 ≤ AHI < 15), 86 cases were moderate (15 ≤ AHI < 30), and 151 cases were severe (AHI ≥ 30). Compared with patients in the mild and moderate groups, the severe group had more male patients, with higher body mass index (BMI) and non-rapid eye movement stage 1 accounted for total sleep time (N1%), and lower non-rapid eye movement stage 2 accounted for total sleep time (N2%), average and minimum blood oxygen. Among all the patients, those who underwent the titration test accounted for 20.6% (63/306). Multivariate analysis showed that sleep efficiency (p < 0.001) and AHI (p < 0.001) were independent factors for patients to accept titration test. OSA patients with hypertension had a low acceptance of titration therapy. These people with higher sleep efficiency and AHI were more likely to receive autotitration.

Practice Recommendations for Diagnosis and Treatment of the Most Common Forms of Secondary Hypertension

The vast majority of hypertensive patients are never sought for a cause of their high blood pressure, i.e. for a 'secondary' form of arterial hypertension. This under detection explains why only a tiny percentage of hypertensive patients are ultimately diagnosed with a secondary form of arterial hypertension. The prevalence of these forms is, therefore, markedly underestimated, although, they can involve as many as one-third of the cases among referred patients and up to half of those with difficult to treat hypertension. The early detection of a secondary form is crucial, because if diagnosed in a timely manner, these forms can be cured at long-term, and even when cure cannot be achieved, their diagnosis provides a better control of high blood pressure, and allows prevention of hypertension-mediated organ damage, and related cardiovascular complications. Enormous progress has been made in the understanding, diagnostic work-up, and management of secondary hypertension in the last decades. The aim of this minireview is, therefore, to provide updated concise information on the screening, diagnosis, and management of the most common forms, including primary aldosteronism, renovascular hypertension, pheochromocytoma and paraganglioma, Cushing's syndrome, and obstructive sleep apnea.

Sleep Apnea, Hypertension and the Sympathetic Nervous System in the Adult Population

Sleep apnea is very common in patients with cardiovascular disease, especially in patients with hypertension. Over the last few decades a number of discoveries have helped support a causal relationship between the two and even resistant hypertension. The role neurogenic mechanisms play has gathered more attention in the recent past due to their immediate bedside utility. Several innovative discoveries in pathogenesis including those exploring the role of baroreflex gain, cardiovascular variability, chemoreceptor reflex activation and the sympathetic nervous system have emerged. In this review, we discuss the epidemiology of sleep apnea and hypertension and the pathogenic mechanisms contributing to neurogenic hypertension. Furthermore, recent management strategies in addition to continuous positive airway pressure (CPAP), such as upper airway stimulation and renal denervation that target these pathogenic mechanisms, are also discussed.

A meta-analysis of continuous positive airway pressure therapy in prevention of cardiovascular events in patients with obstructive sleep apnoea

Aims

To assess whether continuous positive airway pressure (CPAP) therapy reduces major adverse cardiovascular events (MACE) in patients with moderate-to-severe obstructive sleep apnoea (OSA).

Methods and results

A total of 235 articles were recovered using MEDLINE, EMBASE and Cochrane library (inception-December 2016) and references contained in the identified articles. Seven randomized controlled trials (RCTs) were selected for final analysis. Analysis of 4268 patients demonstrated non-significant 26% relative risk reduction in MACE with CPAP [risk ratio (RR) 0.74; 95% confidence interval (CI) 0.47-1.17; P = 0.19, I2 = 48%]. A series of sensitivity analyses suggested that increased CPAP usage time yielded significant risk reduction in MACE. and stroke. Subgroup analysis revealed that CPAP adherence time ≥4 hours (h)/night reduced the risk of MACE by 57% (RR 0.43; 95% CI 0.23-0.80; P = 0.01, I2 = 0%). CPAP therapy showed no beneficial effect on myocardial infarction (MI), all-cause mortality, atrial fibrillation/flutter (AF), or heart failure (HF) (P > 0.05). CPAP had positive effect on mood and reduced the daytime sleepiness [Epworth Sleepiness Scale (ESS): mean difference (MD) -2.50, 95% CI - 3.62, -1.39; P < 0.001, I2 = 81%].

Conclusion

CPAP therapy might reduce MACE and stroke among subjects with CPAP time exceeding 4 h/night. Additional randomized trials mandating adequate CPAP time adherence are required to confirm this impression.

[Non-surgical treatment of the sleep related breathing disorders in adults]

The treatment of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) must allow for the suppression of symptoms and also prevent its immediate and long-term consequences. The evaluation of the effectiveness of treatments is now based on a normal apnea/hypopnea index, a normal oxygen saturation and the disappearance of sleep fragmentation. Clinical and biological follow-up of co-morbidities must be ensured. Compliance with treatment, a major element of success, must be monitored. Continuous Positive Airway Pressure (CPAP) is still the most effective and widely used treatment. However, mandibular advancement orthosis is now recommended as a first-line treatment in moderate forms in the absence of severe cardiovascular comorbidities (CV) and remains a therapeutic alternative in the event of refusal or intolerance to CPAP. Nutritional management in cases of obesity and a physical activity program must be systematically offered. A reduction in nocturnal breathing disorders can also be achieved by using a device in the event of positional OSAHS, or by limiting fluid movements. The contribution of myofunctional therapy is currently being evaluated. Very recently, a study testing the efficiency of pharmacological treatment on the severity of OSAHS and the reactivity of geniogloss appears to be promising. The evaluation of these different treatments and their combination should make it possible to evolve towards a personalised management adapted to each patient.

Update on oral appliance therapy

Oral appliances are increasingly recommended for selected patients with obstructive sleep apnoea (OSA) and those who do not tolerate nor prefer continuous positive airway pressure. The most commonly used oral appliance advances the lower jaw during sleep, the so-called mandibular advancement device (MAD). Patients seek treatment because of disturbing snoring, daytime symptoms, apnoeas that disturb sleep and the longer term consequences with regard to cardiovascular risks. MADs reduce the apnoea–hypopnoea index, although to various degrees among patients. Effects on daytime sleepiness have been observed mainly among the more severe OSA patients. Blood pressure may be reduced in MAD-treated OSA patients. There is, however, uncertainty about which patients will respond to this therapy in terms of apnoea reductions, decreased sleepiness and other symptoms, and reduced risk for future impaired health. The occurrence of side-effects also remains difficult to predict at present. The majority of sleep apnoea patients suffer from various comorbidities in terms of cardiovascular diseases, type 2 diabetes and depression. The most recent findings indicate that phenotyping of patients, considering various aspects of this multifaceted disease, will shed more light on the indications for MADs in patients with nightly sleep breathing disturbances. This review summarises the most recent knowledge about MAD treatment.

Sleep Apnea and Cardiovascular Disease: An Enigmatic Risk Factor

Synchronization of molecular, metabolic, and cardiovascular circadian oscillations is fundamental to human health. Sleep-disordered breathing, which disrupts such temporal congruence, elicits hemodynamic, autonomic, chemical, and inflammatory disturbances with acute and long-term consequences for heart, brain, and circulatory and metabolic function. Sleep apnea afflicts a substantial proportion of adult men and women but is more prevalent in those with established cardiovascular diseases and especially fluid-retaining states. Despite the experimental, epidemiological, observational, and interventional evidence assembled in support of these concepts, this substantial body of work has had relatively modest pragmatic impact, thus far, on the discipline of cardiology. Contemporary estimates of cardiovascular risk still are derived typically from data acquired during wakefulness. The impact of sleep-related breathing disorders rarely is entered into such calculations or integrated into diagnostic disease-specific algorithms or therapeutic recommendations. Reasons for this include absence of apnea-related symptoms in most with cardiovascular disease, impediments to efficient diagnosis at the population level, debate as to target, suboptimal therapies, difficulties mounting large randomized trials of sleep-specific interventions, and the challenging results of those few prospective cardiovascular outcome trials that have been completed and reported. The objectives of this review are to delineate the bidirectional interrelationship between sleep-disordered breathing and cardiovascular disease, consider the findings and implications of observational and randomized trials of treatment, frame the current state of clinical equipoise, identify principal current controversies and potential paths to their resolution, and anticipate future directions.

Acute effects of continuous positive airway pressure in patients with obstructive sleep apnea

Objectives. To enhance the initial compliance of continuous positive airway pressure (CPAP) in the patient with obstructive sleep apnea (OSA), we investigate the acute effects of one-night CPAP on morning blood pressure (BP) and, if any exist, to determine which factors predict BP-lowering effects of one-night CPAP in OSA subgroups stratified by the presence or absence of uncontrolled hypertension. Design. Newly diagnosed OSA patients (a respiratory distress index (RDI) ≥ 15) without a history of hypertension were stratified by the presence or absence of morning hypertension. Comparisons were made of morning BP, overnight change in mean BP (MBP), and circadian BP pattern (R_M/E, the ratio of morning to evening MBP) between two time points of diagnostic and CPAP titrations in each subgroup. In the subgroup with a significantly reduced morning BP, predictors of changes in morning MBP were determined by multiple linear regression analyses. Results. The prevalence of morning hypertension was 48.8%. One-night CPAP reduced BP immediately only in patients with morning hypertension. By contrast, patients without morning hypertension did not experience any BP-lowering effects. In the subgroup with morning hypertension, baseline morning MBP, female sex, and R_M/E were independently associated with reduced morning MBP, and R_M/E was the most important predictor. Conclusions. These results confirm the acute effects of one-night CPAP on lowering BP in OSA patients with morning hypertension. An unfavorable circadian BP pattern is the most important predictor.

Differential blood pressure response to continuous positive airway pressure treatment according to the circadian pattern in hypertensive patients with obstructive sleep apnoea

Continuous positive airway pressure (CPAP) has a heterogeneous effect on blood pressure (BP) in hypertensive patients. However, the effect of CPAP on BP in hypertensive subjects regarding circadian BP pattern has never been explored. This study aimed to assess the effect of CPAP on BP, taking into consideration the circadian BP pattern in untreated hypertensive patients.This study is a post hoc analysis of the Spanish Cohort for the Study of the Effect of CPAP in Hypertension (CEPECTA), a multicentre, randomised trial of CPAP versus sham-CPAP in patients with new-onset systemic hypertension and an apnoea-hypopnoea index >15 events·h^-1 We included patients for whom 24-h ambulatory BP monitoring (ABPM) data were available at baseline and 12 weeks after the intervention. Subjects were classified based on the dipping ratio (dipper/non-dipper). We evaluated the effect of CPAP on ABPM parameters after 12 weeks of treatment.Overall, 272 hypertensive subjects were included in the analysis (113 dippers and 159 non-dippers). Baseline clinical and polysomnographic variables were similar between the groups. CPAP treatment in non-dipper patients was associated with reductions in 24-h ambulatory BP variables and night-time ambulatory BP measurements. However, a nonsignificant effect was reported in the dipper group. The differential effects of CPAP between the groups were -2.99 mmHg (95% CI -5.92-- -0.06 mmHg) for the mean 24-h ambulatory BP and -5.35 mmHg (95% CI -9.01- -1.69 mmHg) for the mean night-time ambulatory BP.Our results show a differential effect of CPAP treatment on BP in hypertensive patients depending on the circadian pattern. Only non-dipper patients benefited from CPAP treatment in terms of BP reduction.

Non-invasive ventilation for obese patients with chronic respiratory failure: Are two pressures always better than one?

Obesity-related respiratory failure is increasingly common but remains under-diagnosed and under-treated. There are several clinical phenotypes reported, including severe obstructive sleep apnoea (OSA), isolated nocturnal hypoventilation with or without severe OSA and OSA complicating chronic obstructive pulmonary disease (COPD). The presence of hypercapnic respiratory failure is associated with poor clinical outcomes in each of these groups. While weight loss is a core aim of management, this is often unachievable, and treatment of sleep-disordered breathing with positive airway pressure (PAP) therapy is the mainstay of clinical practice. Although there are few long-term clinical efficacy trials, the lack of equipoise would prevent the utilization of an untreated control group. The current data support the use of PAP therapy to improve respiratory failure and is associated with improvements in health-related quality of life, reduced healthcare utilization and reduced mortality. Both continuous PAP (CPAP) and non-invasive ventilation (NIV) appear safe and effective in patients with obesity-related respiratory failure and OSA, with or without COPD, and the current evidence would not support a single therapy choice in all patients. There are no studies of CPAP in patients with isolated nocturnal hypoventilation, and NIV would be the current recommendation in this patient group. Whichever starting therapy is used, titration should be performed to correct sleep-disordered breathing and reverse chronic respiratory failure, with consideration of step-down of the treatment based on a clinical re-evaluation. In contrast, failure to reach physiological and clinical treatment targets should lead to the consideration of treatment escalation.

Reduction in sympathetic tone in patients with obstructive sleep apnoea: is fixed CPAP more effective than APAP? A randomised, parallel trial protocol

INTRODUCTION

Obstructive sleep apnoea (OSA) is a prevalent disease associated with cardiovascular events. Hypertension is one of the major intermediary mechanisms leading to long-term cardiovascular adverse events. Intermittent hypoxia and hypercapnia associated with nocturnal respiratory events stimulate chemoreflexes, resulting in sympathetic overactivity and blood pressure (BP) elevation. Continuous positive airway pressure (CPAP) is the primary treatment for OSA and induces a small but significant reduction in BP. The use of auto-adjusting positive airway pressure (APAP) has increased in the last years and studies showed different ranges of BP reduction when comparing both modalities. However, the pathophysiological mechanisms implicated are not fully elucidated. Variations in pressure through the night inherent to APAP may induce persistent respiratory efforts and sleep fragmentation that might impair sympathovagal balance during sleep and result in smaller decreases in BP. Therefore, this double-blind randomised controlled trial aims to compare muscle sympathetic nerve activity (MSNA) assessed by microneurography (reference method for measuring sympathetic activity) after 1 month of APAP versus fixed CPAP in treatment-naive OSA patients. This present manuscript describes the design of our study, no results are presented herein. and is registered under the below reference number.

METHODS AND ANALYSIS

Adult subjects with newly diagnosed OSA (Apnoea-Hypopnoea Index >20/hour) will be randomised for treatment with APAP or fixed CPAP. Measurements of sympathetic activity by MSNA, heart rate variability and catecholamines will be obtained at baseline and after 30 days. The primary composite outcome will be the change in sympathetic tone measured by MSNA in bursts/min and bursts/100 heartbeats. Sample size calculation was performed with bilateral assumption. We will use the Student's t-test to compare changes in sympathetic tone between groups.

ETHICS AND DISSEMINATION

The protocol was approved by The French Regional Ethics Committee. The study started in March 2018 with primary completion expected to March 2019. Dissemination plans of the results include presentations at conferences and publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03428516; Pre-results.

A Novel Grading System for Salpingopharyngeal Fold Hypertrophy in Obstructive Sleep Apnoea

The present study aimed at reporting the incidence of Salpingopharyngeal Fold (SPF) hypertrophy on Drug Induced Sleep Endoscopy (DISE) in patients with Obstructive Sleep Apnoea (OSA, validate a grading system and analyse the impact of various grades on the clinical presentation while ascertaining its relation with Apnoea-Hypopnoea Index (AHI). A retrospective analysis of 169 patients with polysomnographic confirmation of obstructive sleep apnoea has been done in the study. The DISE video data of 169 patients was evaluated by two ENT surgeons individually and they graded the hypertrophy of the fold as Grade 0 being normal anatomy, Grade 1 being hypertrophy causing partial obstruction and Grade 2 being hypertrophy causing complete obstruction of lateral pharyngeal wall. It was found that the presence of SPF hypertrophy independently adds considerably to the severity of the obstruction, attributing to lateral collapse at the upper retropalatal level and also significantly increases AHI. It is thus advised to consider the grade of SPF hypertrophy while surgically planning the management of patients with OSA.

Pro: should asymptomatic patients with moderate-to-severe OSA be treated?

Substantial evidence points to a benefit with CPAP on cardiovascular and metabolic outcomes in asymptomatic patients with moderate-to-severe obstructive sleep apnoea http://ow.ly/FUxN30nkTqU.