Effect of ventilation therapy on mortality rate among obesity hypoventilation syndrome and obstructive sleep apnoea patients

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

The most common pulmonary diseases length of stay, and characteristics of patients admitted to pulmonary service

BACKGROUND

Although chronic respiratory diseases are prevalent in Saudi Arabia, there are limited data on the patient burden and associated factors. The aim of this study is to identify the chronic respiratory diseases frequently admitted to pulmonary services and to determine the patient's characteristics, associated comorbidities readmission rate, and reason for a more extended stay in hospital.

METHODS

A prospective study was conducted over a 5-year period at King Abdulaziz Medical City-Riyadh, Saudi Arabia, in the Pulmonary Division, between March 2015 and December 2019. Data on demographics, comorbidities, and chronic respiratory diseases were collected.

RESULTS

Total patients admitted were 1315 patients, female 54.2%, the mean age was 62.4 (SD±17.6), and the ages ranged from 14 to 98 years. Overall, chronic obstructive pulmonary disease was the most common respiratory disease requiring admission (17.9%), followed by interstitial lung disease (15.8%), bronchiectasis (11.9%), and obesity hypoventilation syndrome (10.8%). The most common comorbidities were obesity (42.5%), diabetes 49.1%, and hypertension 54.9%. Only 135 (10.3%) were readmitted within 30 days posthospital discharge. Among the patients who were readmitted, 103 (76.3%) were readmitted due to issues related to previous admission diagnosis, noncompliance 75 (55.5%), social reasons, and premature discharges in 51 (37.8%) and 29 (21.5%) of the cases, respectively. The respiratory disease varied significantly by gender, age, obesity status, comorbidities, length of stay (LOS), and admissions.

CONCLUSION

Chronic respiratory diseases are prevalent in our population and are mainly influenced by gender, age, obesity status, comorbidities, LOS, and admissions. Policymakers and health professionals need to recognize the burden of chronic respiratory diseases on patients and health systems and implement effective prevention programs.

[Compliance with CPAP treatment in patients with obstructive sleep apneas during the COVID-19 pandemic in two hospitals in the Federal Capital]

Introduction

CPAP therapy is the first line treatment for sleep apnea and its effectiveness depends on adherence. Face to face control and follow-up was limited due to the fact that our country was immersed in social isolation due to the COVID-19 pandemic as of March 2020. In order to assess whether CPAP adherence was maintained in patients with obstructive sleep apnea (OSA), in two hospitals during the COVID-19 pandemic and compare it with the pre-pandemic situation on a historical control basis in the city of Buenos Aires.

Methods

Observational and retrospective study based on systematic data collection of adherence to CPAP and residual apnea-hypopnea index (AHI). For comparison, a historical control corresponding to the specular period (May to December of each year between 2016 and 2019) was used as a reference. Patients over 18 years ago with OSA on CPAP therapy more than 30 days of treatment were included. Patients with other chronic respiratory diseases requiring ventilation therapy (Bi-level, servo ventilation, volume-assured ventilation) were excluded.

Results

151 pre-pandemic patients and 127 from the pandemic period, respectively, were evaluated. Men 98 (65%) vs. 50 (60.3%) p: 0.9, age: 65.4 ± 11.9 vs. 63.6 ± 12.6 p: 0.22, body mass index 31.5 ± 5.0 vs. 31.2 ± 5.3 kg/m2 p: 0.6, respectively. In both centers, the most used treatment was fixed CPAP; 90 (59.6%) vs. 96 (75.6%) p: 0.005. There was an increase in compliance with it compared to the pre-pandemic period in minutes/night [341.4 95% CI 292.4 - 340.6 vs. 274.3 95% CI 208.5 - 267.4, p: 0.001] and residual AHI reduction [3.3 IC 95% 2.0 - 3.05 vs. 6.3 IC 95% 2.6 - 4.3 p: 0.006].

Conclusions

In the period of the COVID-19 pandemic, greater adherence to CPAP treatment was observed in patients with sleep apnea.

Clinical Evaluation and Management of Overlap Syndrome (OS) and Obesity Hypoventilation Syndrome (OHS)

Background and Aim: Sleep-disordered breathing (SDB) is an extremely common disorder with a high impact on morbidity and mortality. The purpose of this study was to compare overlap syndrome (OS) and obesity hypoventilation syndrome (OHS) and to highlight and understand the differences between them. Material and Methods: The study was conducted retrospectively on 132 subjects selected by consecutive sampling from those attending our unit for suspected SDB. After clinical evaluation as well as functional and sleep investigations, the population was divided according to diagnosis in OS and OHS; then, the clinical parameters of two groups were compared with different statistical analysis. Results: The subjects with OHS were younger and reported higher rated daytime sleepiness (p = 0.005). In addition, they presented more nocturnal respiratory events (apnea-hypopnea index (AHI) 63.61 ± 22.79 events·h−1 vs. AHIOS 42.21 ± 22.91 events·h−1, p < 0.0001) at the sleep investigation as worse gas exchange during sleep leading to a higher percentage of nocturnal hypoxemia (p < 0.0001). In contrast, subjects with OS had more an impaired respiratory function. With regard to night-time ventilatory therapy, more subjects with OS were effectively treated with continuous positive airway pressure (CPAP) (p = 0.011), while more OHS were treated with auto-adjusting PAP (APAP) (14% vs. 1%, p = 0.008). Conclusions: The present study tried to establish a framework for OS and OHS because proper management of the two disorders would reduce their burden on healthcare.

Obesity-associated sleep hypoventilation and increased adverse postoperative bariatric surgery outcomes in a large clinical retrospective cohort

STUDY OBJECTIVES

Although obesity hypoventilation syndrome (OHS) is associated with increased morbidity and mortality, post-bariatric surgery OHS risk remains unclear due to often nonsystematic OHS assessments.

METHODS

We leverage a clinical cohort with nocturnal CO2 monitoring during polysomnography to address the hypothesis that patients with obesity-associated sleep hypoventilation (OaSH; ie, stage II OHS) have increased adverse postoperative bariatric surgery outcomes. We retrospectively analyzed data from patients undergoing pre-bariatric surgery polysomnography at the Cleveland Clinic from 2011-2018. OaSH was defined by body mass index ≥ 30 kg/m2 and either polysomnography-based end-tidal CO2 ≥ 45 mmHg or serum bicarbonate ≥ 27 mEq/L. Outcomes considered were as follows: intensive care unit stay, intubation, tracheostomy, discharge disposition other than home or 30-day readmission individually and as a composite, and all-cause mortality. Two-sample t test or Wilcoxon rank-sum test for continuous variables and chi-square or Fisher's exact test for categorical variables were used for OaSH vs non-OaSH comparisons. All-cause mortality was compared using Kaplan-Meier estimation and Cox proportional hazards models.

RESULTS

The analytic sample (n = 1,665) was aged 45.2 ± 12 years, 20.4% were male, had a body mass index of 48.7 ± 9 kg/m2, and 63.6% were White. OaSH prevalence was 68.5%. OaSH patients were older and more likely to be male with a higher BMI, apnea-hypopnea index, and glycated hemoglobin. The composite outcome was higher in OaSH vs non-OaSH patients (18.9% vs 14.3%, P = .021). Although some individual outcomes were respectively higher in OaSH vs non-OaSH patients, differences were not statistically significant: intubation (1.5% vs 1.3%, P = .81) and 30-day readmission (13.8% vs 11.3%, P = .16). Long-term mortality (median follow-up: 22.9 months) was not significantly different between groups, likely due to overall low event rate (hazard ratio = 1.39, 95% confidence interval: 0.56, 3.42).

CONCLUSIONS

In this largest sample to date of systematically phenotyped OaSH in a bariatric surgery cohort, we identify increased postoperative morbidity in those with sleep-related hypoventilation in stage II OHS when a composite outcome was considered, but individual contributors of intubation, intensive care unit admission, and hospital length of stay were not increased. Further study is needed to identify whether perioperative treatment of OaSH improves post-bariatric surgery outcomes.

CITATION

Chindamporn P, Wang L, Bena J, et al. Obesity-associated sleep hypoventilation and increased adverse postoperative bariatric surgery outcomes in a large clinical retrospective cohort. J Clin Sleep Med. 2022;18(12):2793-2801.

The prevalence of non-invasive ventilation and long-term oxygen treatment in Helsinki University Hospital area, Finland

BACKGROUND

Chronic respiratory failure (CRF) can be treated at home with non-invasive ventilation (NIV) and/or long-term oxygen (LTOT). The prevalence of these treatments is largely unknown. We aimed to clarify the prevalence and indications of the treatments, and the three-year mortality of the treated patients in the Helsinki University Hospital (HUH) area in Finland.

METHODS

In this retrospective study we analyzed the prevalence of adult CRF patients treated with NIV and/or LTOT on 1.1.2018 and followed these patients until 1.1.2021. Data collected included the underlying diagnosis, patient characteristics, information on treatment initiation and from the last follow-up visit, and mortality during the three-year follow-up. Patients with home invasive mechanical ventilation or sleep apnea were excluded.

RESULTS

On 1.1.2018, we had a total of 815 patients treated with NIV and/or LTOT in the Helsinki University Hospital (HUH) area, with a population of 1.4 million. The prevalence of NIV was 35.4 per 100,000, of LTOT 24.6 per 100,000 and of the treatments combined 60.0 per 100,000. Almost half, 44.5%, were treated with NIV, 41.0% with LTOT, and 14.4% underwent both. The most common diagnostic groups were chronic obstructive pulmonary disease (COPD) (33.3%) and obesity-hypoventilation syndrome (OHS) (26.6%). The three-year mortality in all patients was 45.2%. In the COPD and OHS groups the mortality was 61.3% and 21.2%. In NIV treated patients, the treatment durations varied from COPD patients 5.3 years to restrictive chest wall disease patients 11.4 years. The age-adjusted Charlson co-morbidity index (ACCI) median for all patients was 3.0.

CONCLUSIONS

NIV and LTOT are common treatments in CRF. The prevalence in HUH area was comparable to other western countries. As the ACCI index shows, the treated patients were fragile, with multiple co-morbidities, and their mortality was high. Treatment duration and survival vary greatly depending on the underlying diagnosis.

Development of Home Mechanical Ventilation in Poland in 2009–2019 Based on the Data of the National Health Fund

Home mechanical ventilation (HMV) is a dynamically developing field of medicine driven by the increasing number of patients and technological advancements. In Poland, HMV has been financed from public funds since 2004. However, the organization of HMV is still evolving in search of the optimal model of care. The aim of this study was to analyze 11 years of HMV in terms of the number of patients, modes of ventilation, diagnosis and regional prevalence. In retrospective analysis of data reported to the National Health Fund by all health entities providing HMV in Poland in the period from 2009 to 2019, the following variables were included: age, sex, date of commencement, ventilation mode, diagnosis, and place of treatment. The diseases were identified according to the ICD-10 codes. A total of 12,616 patients receiving HMV were reported, including 1221 children (9.7%). The HMV prevalence increased from 2.8 in 2009 to 20/100,000 in 2019. In adults, the highest increase was reported for patients with chronic obstructive pulmonary disease, who accounted for 39% of all HMV users in 2019. The proportion of noninvasive ventilation (NIV) increased from 56% in 2014 to 73% in 2019. We identified significant regional variations in the prevalence of HMV between provinces. The main drivers for HMV development include full reimbursement, the development of hospital NIV centers and the involvement of respiratory physicians in the referral process for HMV.

PAP therapy and readmission rates after in-hospital laboratory titration polysomnography in patients with hypoventilation

STUDY OBJECTIVES

Hypoventilation associated with sleep disordered breathing in inpatients is associated with higher risk of morbidity, hospitalizations and death. In-hospital titration polysomnography qualifies patients for positive airway pressure (PAP) therapy and optimizes settings, but impact is unknown. This study describes a process for in-hospital sleep testing and evaluates subsequent PAP adherence and readmission.

METHODS

A retrospective cohort of patients with hypoventilation and in-hospital titration polysomnography with available PAP data were analyzed to determine whether PAP adherence was associated with 90-day readmission. Absolute differences were obtained using logistic regression models. Models were adjusted for body mass index, age and Elixhauser Index. PAP adherence and nonadherence were defined as ≥ 4 and < 4 hours daily average use prior to readmission or first 90-days post-discharge.

RESULTS

81 patients, 50.6% male, age (mean ± SD) 61.1 ± 13.5 years were included. Comorbid sleep disorders included 91.4% with OSA and 23.5% with central sleep apnea. 28/52 (53.8%) nonadherent and 6/29 (20.7%) adherent patients had 90-day readmissions. 11 (13.6%) patients (all nonadherent) were readmitted within 2 weeks of discharge. Adjusted model showed a 35.6% (95% CI 15.9%-55.2%) reduction in 90-day readmission in adherent group compared to nonadherent (p=0.004). Similar reductions in readmission were found with adherence ≥ 50% and ≥ 70% days ≥ 4 hours. Male sex, treatment with iVAPS, and highest CO₂ ≥ 60 mmHg on polysomnography were associated with largest differences in readmission rates between adherent and nonadherent patients.

CONCLUSIONS

Adherence to optimized PAP therapy after in-hospital titration polysomnography in patients with hypoventilation may decrease readmissions.

Cardiopulmonary coupling and serum cardiac biomarkers in obesity hypoventilation syndrome and obstructive sleep apnea with morbid obesity

STUDY OBJECTIVES

The main cause of death in patients with obesity hypoventilation syndrome (OHS) is cardiac rather than respiratory failure. Here, we investigated autonomic-respiratory coupling and serum cardiac biomarkers in patients with OHS and obstructive sleep apnea (OSA) with comparable body mass index (BMI) and apnea-hypopnea index (AHI).

METHODS

Cardiopulmonary coupling (CPC) and cyclic variation of heart rate (CVHR) analysis was performed on the electrocardiogram signal from the overnight polysomnogram. Cardiac serum biomarkers were obtained in patients with OHS and OSA with a BMI > 40kg/m². Samples were obtained at baseline and after 3 months of positive airway pressure (PAP) therapy in both groups.

RESULTS

Patients with OHS (n=15) and OSA (n=36) were recruited. No group differences in CPC, CVHR and serum biomarkers were observed at baseline and after 3 months of PAP therapy. An improvement in several CPC metrics, including the sleep apnea index, unstable sleep (low frequency coupling and elevated low frequency coupling narrow band [e-LFC_NB]) and CVHR were observed in both groups with PAP use. However, distinct differences in response characteristics were noted. e-LFC_NB coupling correlated with highly sensitive troponin (hs-troponin-T, p<0.05) in the combined cohort. Baseline hs-troponin-T inversely correlated with awake oxygen saturation in the OHS group (p<0.05).

CONCLUSIONS

PAP therapy can significantly improve CPC stability in obese patients with OSA or OHS, with key differences. e-LFC_NB may function as a surrogate biomarker for early subclinical cardiac disease. Low awake oxygen saturation could also increase this biomarker in OHS.

CLINICAL TRIAL REGISTRATION

Registry: Australian New Zealand Clinical Trials Registry; Name: Obesity Hypoventilation Syndrome and Neurocognitive Dysfunction; URL: https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367492; Identifier: ACTRN12615000122550.

Cardiovascular disease in obesity hypoventilation syndrome - A review of potential mechanisms and effects of therapy

Cardiovascular disease is common in patients with obesity hypoventilation syndrome (OHS) and accounts in part for their poor prognosis. This narrative review article examines the epidemiology of cardiovascular disease in obesity hypoventilation syndrome, explores possible contributing factors and the effects of therapy. All studies that included cardiovascular outcomes and biomarkers were included. Overall, there is a higher burden of cardiovascular disease and cardiovascular risk factors among patients with obesity hypoventilation syndrome. In addition to obesity and sleep-disordered breathing, there are several other pathophysiological mechanisms that contribute to higher cardiovascular morbidity and mortality in OHS. There is evidence emerging that positive airway pressure therapy and weight loss have beneficial effects on the cardiovascular system in obesity hypoventilation syndrome patients, but further research is needed to clarify whether this translates to clinically important outcomes.

Does testing for sleep-disordered breathing pre-discharge versus post-discharge result in different treatment outcomes?

STUDY OBJECTIVES

Treatment of sleep-disordered breathing (SDB) may improve health related outcomes post-discharge. However timely definitive sleep testing and provision of ongoing therapy has been a challenge. Little is known about how the time of testing-during hospitalization vs. after discharge-affects important outcomes such as treatment adherence.

METHODS

We conducted a 10-year retrospective study of hospitalized adults who received an inpatient sleep medicine consultation for SDB and subsequent sleep testing. We divided them into inpatient and outpatient sleep testing cohorts and studied their clinical characteristics, follow-up and PAP adherence, and hospital readmission.

RESULTS

Of 485 patients, 226 (47%) underwent inpatient sleep testing and 259 (53%) had outpatient sleep testing. The median age was 68 years old (IQR=57-78), and 29.6% were females. The inpatient cohort had a higher Charlson Comorbidity Index (CCI) (4 [3-6] vs 3[2-5], p=<0.0004). A higher CCI (HR=1.14, 95%CI:1.03-1.25, p=0.001), BMI (HR=1.03, 95%CI:1.0-1.05, p=0.008) and stroke (HR=2.22, 95%CI:1.0-4.9, p=0.049) were associated with inpatient sleep testing. The inpatient cohort kept fewer follow-up appointments (39.90% vs 50.62%, p=0.03) however PAP adherence was high among those keeping follow-up appointments (88.9% [inpatient] vs 85.71% [outpatient], p=0.55). The inpatient group had an increased risk for death (HR: 1.82 95%CI 1.28-2.59, p=<0.001) but readmission rates did not differ.

CONCLUSIONS

Medically complex patient were more likely to receive inpatient sleep testing but less likely to keep follow-up, which could impact adherence and effectiveness of therapy. Novel therapeutic interventions are needed to increase sleep medicine follow-up post-discharge which may result in improvement in health outcomes in hospitalized patients with SDB.

Sleep apnoea is a risk factor for severe COVID-19

Background

Obstructive sleep apnoea (OSA) is associated with higher body mass index (BMI), diabetes, older age and male gender, which are all risk factors for severe COVID-19.

We aimed to study if OSA is an independent risk factor for COVID-19 infection or for severe COVID-19.

Methods

OSA diagnosis and COVID-19 infection were extracted from the hospital discharge, causes of death and infectious diseases registries in individuals who participated in the FinnGen study (n=260 405). Severe COVID-19 was defined as COVID-19 requiring hospitalisation. Multivariate logistic regression model was used to examine association. Comorbidities for either COVID-19 or OSA were selected as covariates. We performed a meta-analysis with previous studies.

Results

We identified 445 individuals with COVID-19, and 38 (8.5%) of them with OSA of whom 19 out of 91 (20.9%) were hospitalised. OSA associated with COVID-19 hospitalisation independent from age, sex, BMI and comorbidities (p-unadjusted=5.13×10⁻⁵, OR-adjusted=2.93 (95% CI 1.02 to 8.39), p-adjusted=0.045). OSA was not associated with the risk of contracting COVID-19 (p=0.25). A meta-analysis of OSA and severe COVID-19 showed association across 15 835 COVID-19 positive controls, and n=1294 patients with OSA with severe COVID-19 (OR=2.37 (95% 1.14 to 4.95), p=0.021).

Conclusion

Risk for contracting COVID-19 was the same for patients with OSA and those without OSA. In contrast, among COVID-19 positive patients, OSA was associated with higher risk for hospitalisation. Our findings are in line with earlier works and suggest OSA as an independent risk factor for severe COVID-19.

[Obesity hypoventilation syndrome and initial compliance with non-invasive ventilation]

INTRODUCTION

The obesity hypoventilation syndrome (OHS) has an increasing prevalence. Compliance with first-line non-invasive ventilation has not been evaluated, taking into account patients' initial comorbidities. This study consisted of identification of the factors associated with compliance with non-invasive ventilation during the first six months of use.

METHODS

A monocentric retrospective study, gathering patients from the pneumology department of Gabriel-Montpied hospital in Clermont-Ferrand, from April 2010 to October 2019. The analysis was carried-out through the collection of computerised medical records (age, mode of entry, patient comorbidities) and compliance reports (average daily hours of use) provided by the regional service provider for the Auvergne area (AIRRA).

RESULTS

Being hospitalized for an acute exacerbation and being older than seventy-five years were factors associated with an improved compliance to non-invasive ventilation, with an increase of 1.47h/d and 2.73h/d (P value: 0.018 and 0.02, respectively). Moreover, patients with obstructive sleep apnea hypopnea syndrome and recipients of therapeutic education may prove more compliant over time.

CONCLUSION

Age greater than seventy-five years and being hospitalized for an acute exacerbation are predictors of better use of non-invasive ventilation in OHS.

Long-term adherence to home mechanical ventilation: a 10-year retrospective, single-centre cohort study

Background

Sleep-disordered breathing (SBD) can be associated with hypercapnic respiratory failure (HRF). Home Mechanical Ventilation (HMV) is the preferred long-term treatment for patients with chronic HRF. We reviewed the database of a large tertiary referral centre for HMV to study the long-term adherence to HMV in chronic hypercapnic patients.

Methods

Data on adherence and characteristics of patients who received HMV for the treatment of SDB were collected over a decade using electronic patient records. The primary outcome parameter in this study was annual non-adherence rate (patients with HMV usage of <4 hours/night in the service divided by the number of all new patients of the same year), secondary outcomes were patients’ characteristics and reasons for low adherence. HMV adherence clinics were established to improve uptake.

Results

Two thousand and two hundred twenty-eight patients with HRF were under active follow-up on HMV at the end of the recording period. In contrast, a total of 1,900 patients had their HMV contracts terminated over the course of a decade (due to non-adherence, transfer to other services or death). Out of those, 222 patients {62 [52–72] years, body-mass index, BMI 40 [35–43] kg/m², 58.1% male, Epworth Sleepiness Scale, ESS 9 [4–15] points, 4% oxygen desaturation index, 4%ODI 32 [20–71] × hour⁻¹, TcCO₂ 6.6 [6.0–7.2] kPa} met the non-adherence criteria (nocturnal usage 0–4 hours). The annual non-adherence rate was 25.5% of all new setups in 2010, and declined to 3.4% in 2019 (relative reduction of 86%, P<0.001). Patients with Obstructive Sleep Apnoea/Obesity Hypoventilation Syndrome (58.2%), Neuromuscular Diseases (NMD) (26.8%) and COPD (13.6%) accounted for most cases of this non-adherent cohort. The vast majority of the patients (96.1%) were established on full-face masks. In 23.4% of patients, substantial weight loss (>10%) was the most common reason for low adherence; general displeasure (21.3%), uncontrolled symptoms (12.8%), claustrophobia (6.7%), mood (4.8%) and mask intolerance (4.3%) caused problems as well.

Conclusions

Non-adherence to HMV in patients with chronic HRF can affect significant proportions of patients. However, the non-adherent rate substantially decreases when individual treatment solutions are offered in multi-disciplinary clinics.