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Abstract The optimal mode of positive airway pressure for patients with obesity hypoventilation syndrome (OHS) has been the topic of some debate since the 1980s. People with OHS constitute a significant proportion of patients enrolled in... more
Abstract The optimal mode of positive airway pressure for patients with obesity hypoventilation syndrome (OHS) has been the topic of some debate since the 1980s. People with OHS constitute a significant proportion of patients enrolled in home ventilation programs using bilevel (BPAP) therapy, even though continuous positive airway pressure (CPAP) corrects sleep-disordered breathing and improves awake gas exchange in many of those with concomitant OSA. The modes of BPAP ventilation available to clinicians have grown in recent years, while evidence around who will benefit from them and under what circumstances remains limited. Studies evaluating PAP therapy have primarily focused on patients with stable disease, although at least a third will present with acutely decompensated disease. Treatment considerations regarding PAP need to encompass the timing of intervention, response to therapy, and the longer-term impact on patient outcomes. We need to gain a better understanding of the different OHS phenotypes beyond the presence or absence of OSA and how these traits influence the response to various PAP therapies.
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Background Recent population level data has identified specific symptom and polysomnographic profiles associated with development of cardiovascular disease (CVD) in obstructive sleep apnoea (OSA). Our aims were to determine whether these... more
Background Recent population level data has identified specific symptom and polysomnographic profiles associated with development of cardiovascular disease (CVD) in obstructive sleep apnoea (OSA). Our aims were to determine whether these profiles were present at diagnosis of OSA in pre-existing CVD and high cardiovascular risk. Methods Participants in the Sydney Sleep Biobank (SSB) database, aged 30-74 years, self-reported presence of CVD (coronary artery disease, cerebrovascular disease, or heart failure). In those without CVD, the Framingham Risk Score (FRS) was calculated to estimate 10-year absolute CVD risk, categorised as “low” (<10%), “intermediate” (10-20%), or “high” (>20%). Groups were compared on symptom and polysomnographic variables. Progress to Date 629 patients (68% male; mean age 54.3 years (SD 11.6); mean BMI 32.3 (SD 8.2)) were included. CVD was reported in 12.2%. Of the remainder, 27.7% had a low risk FRS, 25.4% had intermediate risk and 34.7% had high risk....
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ABSTRACTBackgroundEvaluation 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,... more
ABSTRACTBackgroundEvaluation 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).MethodsUsing 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.ResultsThe ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic...
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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... more
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.
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Obesity hypoventilation syndrome (OHS) has become a common cause of chronic hypercapnic respiratory failure and is now the leading indication for home nocturnal noninvasive positive pressure ventilation (NPPV) in many countries. The... more
Obesity hypoventilation syndrome (OHS) has become a common cause of chronic hypercapnic respiratory failure and is now the leading indication for home nocturnal noninvasive positive pressure ventilation (NPPV) in many countries. The presence of this disorder is often overlooked despite these individuals having frequent contact with health care services several years prior to the diagnosis being made. Once on effective therapy, significant improvements in awake gas exchange, symptoms, and quality of life can be achieved. Although nocturnal positive airway pressure (PAP) therapy is widely used, the most appropriate mode of therapy to manage this condition has yet to be determined. Even when adherence to therapy is high, complete correction of awake hypercapnic respiratory failure may not occur in some patients, highlighting that sleep-disordered breathing (SDB) is not the only factor contributing to underbreathing in OHS. In addition to nocturnal PAP therapy, strategies to promote weight loss and reduce sedentary behavior are crucial to minimize the substantial health and social impacts of this increasingly prevalent condition.
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Page 1. DOI 10.1378/chest.110.6.1581 1996;110;1581-1588 Chest Stiller and Bernhard A. Votteri David M. Claman, Amanda Piper, Mark H. Sanders, Ronald A. Ventilatory Assistance Nocturnal Noninvasive Positive Pressure ...
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Research Interests: Health Care, Clinical Trial, Carbon Dioxide, Medicine, Prospective studies, and 15 moreHumans, Female, Male, Anesthesia, Patient Compliance, Clinical Sciences, Middle Aged, Body Weight, Hypoventilation, Obesity Hypoventilation Syndrome, Hypercapnia, Pulmonary Gas Exchange, Continuous Positive Airway Pressure, Psychomotor Performance, and Outcome measure
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The obesity hypoventilation syndrome (OHS) is associated with significant morbidity and increased mortality compared with simple obesity and eucapnic obstructive sleep apnea. Accurate diagnosis and commencement of early and appropriate... more
The obesity hypoventilation syndrome (OHS) is associated with significant morbidity and increased mortality compared with simple obesity and eucapnic obstructive sleep apnea. Accurate diagnosis and commencement of early and appropriate management is fundamental in reducing the significant personal and societal burdens this disorder poses. Sleep disordered breathing is a major contributor to the developmental of sleep and awake hypercapnia, which characterizes OHS, and is effectively addressed through the use of positive airway pressure (PAP) therapy. This article reviews the current evidence supporting different modes of PAP currently used in managing these individuals.
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Research Interests: Obesity, Medicine, Comorbidity, Prospective studies, Humans, and 15 moreHypertension, Diabetes mellitus, Female, Male, Body Mass Index, Hypothyroidism, Polysomnography, Prevalence, Middle Aged, Hypoventilation, Obesity Hypoventilation Syndrome, Sex Characteristics, Psychology and Cognitive Sciences, Medical and Health Sciences, and postmenopause
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Research Interests: Obesity, Health Education, Quality of life, Medicine, Logistic Regression, and 13 moreHumans, Thorax, Developing World, Clinical Sciences, Polysomnography, Sleep-Disordered Breathing, Oxygen, Chronic obstructive pulmonary disease, Intensive Care Medicine, Hypoventilation, Obesity Hypoventilation Syndrome, Continuous Positive Airway Pressure, and Pulmonary Disease Chronic Obstructive
Research Interests: Quality of life, Medicine, Humans, Female, Male, and 15 morePatient Compliance, Body Mass Index, Risk factors, Clinical Sciences, Middle Aged, Risk Factors, Hypoventilation, Obesity Hypoventilation Syndrome, Continuous Positive Airway Pressure, Severity of Illness Index, Surveys and Questionnaires, noninvasive ventilation, Respiratory function tests, Epworth sleepiness scale, and Positive airway pressure
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Obesity hypoventilation syndrome (OHS) is the most common indication for home ventilation, although the optimal therapy remains unclear, particularly for severe disease. We compared Bi-level and continuous positive airways pressure... more
Obesity hypoventilation syndrome (OHS) is the most common indication for home ventilation, although the optimal therapy remains unclear, particularly for severe disease. We compared Bi-level and continuous positive airways pressure (Bi-level positive airway pressure (PAP); CPAP) for treatment of severe OHS. We conducted a multicentre, parallel, double-blind trial for initial treatment of OHS, with participants randomised to nocturnal Bi-level PAP or CPAP for 3 months. The primary outcome was frequency of treatment failure (hospital admission, persistent ventilatory failure or non-adherence); secondary outcomes included health-related quality of life (HRQoL) and sleepiness. Sixty participants were randomised; 57 completed follow-up and were included in analysis (mean age 53 years, body mass index 55 kg/m(2), PaCO2 60 mm Hg). There was no difference in treatment failure between groups (Bi-level PAP, 14.8% vs CPAP, 13.3%, p=0.87). Treatment adherence and wake PaCO2 were similar after 3...
Research Interests: Quality of life, Treatment Outcome, Humans, Female, Thorax, and 13 moreMale, Patient Compliance, Body Mass Index, Risk factors, Clinical Sciences, Middle Aged, Risk Factors, Obesity Hypoventilation Syndrome, Continuous Positive Airway Pressure, Severity of Illness Index, Surveys and Questionnaires, noninvasive ventilation, and Respiratory function tests
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The role of gender and menopause in obstructive sleep apnoea is well known; however, no study has reported the impact of gender on the clinical presentation and the nocturnal respiratory events in patients with obesity hypoventilation... more
The role of gender and menopause in obstructive sleep apnoea is well known; however, no study has reported the impact of gender on the clinical presentation and the nocturnal respiratory events in patients with obesity hypoventilation syndrome. Therefore, this study prospectively evaluated differences in the clinical characteristics of women and men with obesity hypoventilation syndrome in a large cohort of patients with obstructive sleep apnoea. During the study period, a total of 1973 patients were referred to the sleep clinic with clinical suspicion of obstructive sleep apnoea. All patients underwent overnight polysomnography, during which time spirometry, arterial blood samples and thyroid tests were routinely obtained. Among 1973 consecutive patients, 1693 (617 women) were diagnosed with obstructive sleep apnoea, among whom 144 suffered from obesity hypoventilation syndrome (96 women). The prevalence of obesity hypoventilation syndrome among women and men was 15.6% and 4.5%, respectively (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Women with obesity hypoventilation syndrome were significantly older than men with obesity hypoventilation syndrome (61.5 ± 11.9 years versus 49.1 ± 12.5 years, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Although there were no significant differences between genders regarding symptoms, body mass index, spirometric data or daytime PaCO2 , women with obesity hypoventilation syndrome suffered significantly more from hypertension, diabetes and hypothyroidism. The prevalence of obesity hypoventilation syndrome was higher in post-menopausal (21%) compared with pre-menopausal (5.3%) women (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0001). HCO3 and duration of SpO2 &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;90% were the only independent predictors of obesity hypoventilation syndrome. In conclusion, this study reported that among subjects referred to the sleep disorders clinic for evaluation of obstructive sleep apnoea, obesity hypoventilation syndrome is more prevalent in women than men, and that women with obesity hypoventilation syndrome suffer from significantly more co-morbidities. Post-menopausal women with obstructive sleep apnoea have the highest prevalence of obesity hypoventilation syndrome.
Research Interests: Medicine, Comorbidity, Prospective studies, Humans, Hypertension, and 14 moreDiabetes mellitus, Female, Male, Sleep, Body Mass Index, Hypothyroidism, Polysomnography, Prevalence, Middle Aged, Obesity Hypoventilation Syndrome, Sex Characteristics, Psychology and Cognitive Sciences, Medical and Health Sciences, and postmenopause
STUDY OBJECTIVES Both obesity and airways disease can lead to chronic hypercapnic respiratory failure, which can be managed with positive airway pressure (PAP) therapy. The efficacy of PAP has been studied in obesity hypoventilation... more
STUDY OBJECTIVES Both obesity and airways disease can lead to chronic hypercapnic respiratory failure, which can be managed with positive airway pressure (PAP) therapy. The efficacy of PAP has been studied in obesity hypoventilation syndrome as well as in chronic hypercapnic COPD patients, but not in patients where both obesity and airway obstruction coexist. This pilot study aims to compare the efficacy of continuous positive airway pressure (CPAP) versus bilevel positive airway pressure spontaneous mode (BPAP S mode) in the treatment of hypoventilation disorder with obesity and obstructive airways disease. METHODS We sequentially screened PAP naïve patients with stable chronic hypercapnic respiratory failure (PaCO2 > 45 mmHg), obesity (BMI > 30 kg/m2) and obstructive airways disease. Subjects were randomized to CPAP or BPAP S mode treatment for 3 months. Subjects were blinded to their PAP allocation. Change in awake PaCO2 was the primary endpoint. Secondary endpoints included change in lung function, daytime sleepiness, sleep quality, quality of life, PAP adherence and neurocognitive function. RESULTS A total of 32 subjects were randomized (mean ± SD: Age 61 ± 11 years, BMI 43 ± 7 kg/m2, PaCO2 54 ± 7mmHg, FEV1 1.4 ± 0.6L, AHI 59 ± 35 events/h). Sixteen participants in each PAP group were analyzed. BPAP yielded a greater improvement in PaCO2 compared to CPAP (9.4mmHg, 95% CI 4.3 to 15 mmHg). There were no significant differences in PAP adherence, sleepiness, sleep quality or neurocognitive function between the two therapies. CONCLUSIONS Although both PAP modalities improved hypercapnic respiratory failure in this group of subjects, BPAP S mode showed greater efficacy in reducing PaCO2.
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Over the past decade, increasing attention has been paid to the evaluation and management of obesity hypoventilation syndrome (OHS).1 This disorder is characterised by daytime hypercapnia and three main phenotypes of sleep disordered... more
Over the past decade, increasing attention has been paid to the evaluation and management of obesity hypoventilation syndrome (OHS).1 This disorder is characterised by daytime hypercapnia and three main phenotypes of sleep disordered breathing, including severe obstructive sleep apnoea (OSA), combined OSA and OHS and isolated OHS.2 Rising rates of global obesity along with a greater awareness of the significant health and social costs of this disorder have been driving factors fuelling interest in how best to manage those with OHS. Although the cornerstone of treatment has been to address sleep breathing abnormalities using positive airway pressure (PAP) therapy, the mode of therapy which optimises outcomes in the most cost-effective manner has been less clear.3–6 In many centres, OHS has become a major indication for home ventilation, with most individuals prescribed bilevel therapy.7 However, OHS can present as chronic respiratory failure as a consequence of OSA, OSA and OHS or lone OHS, with the OSA and OSA-OHS phenotypes accounting for more than 90% of individuals diagnosed with OHS, 70% of whom will have apnoea-hypopnea indices>30 events/hour.4 Although continuous single level PAP therapy (CPAP) does not directly provide inspiratory assistance to increase tidal volumes, correction of upper airway obstruction in conjunction with increased resting lung volumes, resetting of the respiratory centres, reduced WOB and prevention of expiratory flow limitation8 can improve gas exchange, alleviate symptoms and improve quality of life. Several medium-term randomised studies3 5 6 and one long term randomised trial9 comparing CPAP to bilevel therapy have failed to find significant differences between these therapies in terms of resolving waking chronic respiratory failure, improving quality of life, therapy adherence, …
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Hypoventilation in obesity is now divided into five stages; stage 0 (pure obstructive sleep apnea; OSA), stages I/II (obesity-related sleep hypoventilation; ORSH) and stages III/IV (awake hypercapnia, obesity hypoventilation syndrome;... more
Hypoventilation in obesity is now divided into five stages; stage 0 (pure obstructive sleep apnea; OSA), stages I/II (obesity-related sleep hypoventilation; ORSH) and stages III/IV (awake hypercapnia, obesity hypoventilation syndrome; OHS). Hypercapnia during the day may be preceded by hypoventilation during sleep. The goal of this study was to determine the prevalence and to identify simple clinical measures that predict stages I/II ORSH. The effect of supine positioning on selected clinical measures was also evaluated. Ninety-four patients with a body mass index > 40 kg/m and a spirometric ratio > 0.7 were randomized to begin testing either in the supine or upright seated position on the day of their diagnostic sleep study. Arterialized capillary blood gases were measured in both positions. Oxygen saturation measured by pulse oximetry was also obtained while awake. Transcutaneous CO monitoring was performed during overnight polysomnography. Stages I/II ORSH had a prevalence ...