Pick Topic
Review Topic
List Experts
Examine Expert
Save Expert
  Site Guide ··   
Sleep Apnea Syndromes: HELP
Articles by Walter T. Mcnicholas
Based on 60 articles published since 2010
(Why 60 articles?)
||||

Between 2010 and 2020, W. McNicholas wrote the following 60 articles about Sleep Apnea Syndromes.
 
+ Citations + Abstracts
Pages: 1 · 2 · 3
1 Editorial Does Associated Chronic Obstructive Pulmonary Disease Increase Morbidity and Mortality in Obstructive Sleep Apnea? 2019

McNicholas, Walter T. ·Department of Respiratory and Sleep Medicine, St. Vincent's Hospital Group, School of Medicine, University College Dublin, Dublin, Ireland; and First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. ·Ann Am Thorac Soc · Pubmed #30592452.

ABSTRACT: -- No abstract --

2 Editorial Identifying and treating obstructive sleep apnea in sleepy drivers: Everybody wins. 2018

McNicholas, Walter T. ·Department of Respiratory and Sleep Medicine, St Vincent's Hospital Group, School of Medicine, University College Dublin, Dublin, Ireland. · First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. ·J Sleep Res · Pubmed #30430695.

ABSTRACT: -- No abstract --

3 Editorial Obstructive sleep apnoea as a cause of nocturnal nondipping blood pressure: recent evidence regarding clinical importance and underlying mechanisms. 2017

Crinion, Sophie J / Ryan, Silke / McNicholas, Walter T. ·Dept of Respiratory and Sleep Medicine, St Vincent's University Hospital, Dublin, Ireland. · School of Medicine and Medical Science, University College Dublin, Dublin, Ireland. · Dept of Respiratory and Sleep Medicine, St Vincent's University Hospital, Dublin, Ireland walter.mcnicholas@ucd.ie. ·Eur Respir J · Pubmed #28077479.

ABSTRACT: -- No abstract --

4 Editorial Driving risk in obstructive sleep apnoea: Do new European regulations contribute to safer roads? 2016

McNicholas, Walter T. ·a Department of Respiratory and Sleep Medicine, St. Vincent's University Hospital, School of Medicine and Medical Science, Conway Institute , University College Dublin , Dublin , Ireland. ·Expert Rev Respir Med · Pubmed #26927224.

ABSTRACT: -- No abstract --

5 Editorial New rules on driver licensing for patients with obstructive sleep apnoea: EU Directive 2014/85/EU. 2016

Bonsignore, Maria R / Randerath, Winfried / Riha, Renata / Smyth, Dan / Gratziou, Christina / Goncalves, Marta / McNicholas, Walter T. ·DiBiMIS, University of Palermo and Institute of Biomedicine and Molecular Immunology (IBIM), National Research Council (CNR), Palermo, Italy marisa@ibim.cnr.it. · Pneumologie und Allergologie Zentrum für Schlaf - und Beatmungsmedizin, Krankenhaus Bethanien, Solingen, Germany. · Sleep and Respiratory Medicine, University of Edinburgh, Edinburgh, UK. · European Lung Foundation Chair. · Medical School, Athens University, Athens, Greece. · Institute of Public Health - University of Porto (ISPUP), Porto, Portugal. · Dept of Respiratory and Sleep Medicine, St. Vincent's University Hospital, University College Dublin, Dublin, Ireland. ·Eur Respir J · Pubmed #26721963.

ABSTRACT: -- No abstract --

6 Editorial Sleep and breathing disorders: a multidisciplinary approach. 2013

McNicholas, Walter T / Bassetti, Claudio L A. · ·Eur Respir Rev · Pubmed #23997044.

ABSTRACT: -- No abstract --

7 Editorial Sleep apnoea and hypertension: time for recommendations. 2013

Lévy, Patrick / McNicholas, Walter T. · ·Eur Respir J · Pubmed #23456933.

ABSTRACT: -- No abstract --

8 Editorial Sleep HERMES: a European training project for respiratory sleep medicine. 2011

De Backer, W / Simonds, A K / Horn, V / Andreas, S / Bonsignore, M / Calverley, P / Donic, V / Lévy, P / Mitchell, S / McNicholas, W T / Morrell, M / Randerath, W / Riha, R L / Trang, H / Verbraecken, J / Palange, P. · ·Eur Respir J · Pubmed #21885409.

ABSTRACT: -- No abstract --

9 Editorial Portable monitoring in sleep apnoea: the way forward? 2011

McNicholas, W T / Lévy, P. · ·Eur Respir J · Pubmed #21454893.

ABSTRACT: -- No abstract --

10 Review Sleepiness and Driving: The Role of Official Regulation. 2019

McNicholas, Walter T. ·Department of Respiratory and Sleep Medicine, School of Medicine, University College Dublin, St. Vincent's Hospital Group, Elm Park, Dublin 4, Ireland; First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. Electronic address: walter.mcnicholas@ucd.ie. ·Sleep Med Clin · Pubmed #31640877.

ABSTRACT: Sleepiness accounts for approximately 20% of major highway motor vehicle accidents (MVAs) and the most common medical disorder associated with sleepiness is obstructive sleep apnea (OSA). OSA patients are 2 to 3 times more likely to have an MVA than the general population, although continuous positive airway pressure therapy can remove this excess risk. Several jurisdictions have introduced regulations to limit driving in patients with moderate or severe OSA associated with sleepiness until the disorder is effectively treated. Successful implementation of such regulations requires education regarding risk-benefit relationships of relevant stakeholders, including patients, clinicians, and employers in the transportation industry.

11 Review Challenges and perspectives in obstructive sleep apnoea: Report by an 2018

Randerath, Winfried / Bassetti, Claudio L / Bonsignore, Maria R / Farre, Ramon / Ferini-Strambi, Luigi / Grote, Ludger / Hedner, Jan / Kohler, Malcolm / Martinez-Garcia, Miguel-Angel / Mihaicuta, Stefan / Montserrat, Josep / Pepin, Jean-Louis / Pevernagie, Dirk / Pizza, Fabio / Polo, Olli / Riha, Renata / Ryan, Silke / Verbraecken, Johan / McNicholas, Walter T. ·Institute of Pneumology at the University of Cologne, Bethanien Hospital, Clinic for Pneumology and Allergology, Centre of Sleep Medicine and Respiratory Care, Solingen, Germany. · Neurology Dept, Inselspital, Bern University Hospital, Bern, Switzerland. · DiBiMIS, University of Palermo and CNR Institute of Biomedicine and Molecular Immunology (IBIM), Palermo, Italy. · Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona-IDIBAPS, Barcelona and CIBERES, Madrid, Spain. · Dept of Neurology OSR-Turro, Sleep Disorders Centre, Università Vita-Salute San Raffaele, Milan, Italy. · Dept of Sleep Medicine, Respiratory Medicine and Allergology, Sahlgrenska University Hospital, Gothenburg, Sweden. · Dept of Pneumology, University Hospital of Zurich, Zurich, Switzerland. · Respiratory Dept, Polytechnic and University La Fe Hospital, Valencia, Spain. · Pulmonology Dept, CardioPrevent Foundation, University of Medicine and Pharmacy Victor Babes Timisoara, Timisoara, Romania. · Sleep Unit, Respiratory Dept, Hospital Clinic, University of Barcelona-IDIBAPS, Barcelona and CIBERES, Madrid, Spain. · HP2 Laboratory, INSERM U1042, Grenoble Alpes University and EFCR Laboratory, Thorax and Vessels Division, Grenoble Alpes University Hospital, Grenoble, France. · Sleep Medicine Centre, Kempenhaeghe Foundation, Heeze, The Netherlands. · Dept of Internal Medicine, Faculty of Medicine and Health Sciences, Ghent University, Belgium. · Dept of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna and IRCCS Institute of the Neurological Sciences, AUSL di Bologna, Bologna, Italy. · Unesta Ltd, Tampere, Finland. · Dept of Sleep Medicine, Royal Infirmary Edinburgh, Edinburgh, UK. · Dept of Respiratory and Sleep Medicine, St Vincent's University Hospital and School of Medicine, University College Dublin, Dublin, Ireland. · Dept of Pulmonary Medicine and Multidisciplinary Sleep Disorders Centre, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium. · First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. ·Eur Respir J · Pubmed #29853491.

ABSTRACT: Obstructive sleep apnoea (OSA) is a major challenge for physicians and healthcare systems throughout the world. The high prevalence and the impact on daily life of OSA oblige clinicians to offer effective and acceptable treatment options. However, recent evidence has raised questions about the benefits of positive airway pressure therapy in ameliorating comorbidities.An international expert group considered the current state of knowledge based on the most relevant publications in the previous 5 years, discussed the current challenges in the field, and proposed topics for future research on epidemiology, phenotyping, underlying mechanisms, prognostic implications and optimal treatment of patients with OSA.The group concluded that a revision to the diagnostic criteria for OSA is required to include factors that reflect different clinical and pathophysiological phenotypes and relevant comorbidities (

12 Review Obstructive sleep apnoea of mild severity: should it be treated? 2017

McNicholas, Walter T. ·aDepartment of Respiratory and Sleep Medicine, St. Vincent's University Hospital, School of Medicine, University College Dublin, Dublin, Ireland bGuangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. ·Curr Opin Pulm Med · Pubmed #28858969.

ABSTRACT: PURPOSE OF REVIEW: To provide guidance in the management of mild obstructive sleep apnoea syndrome (OSAS) in the context of a very high prevalence, poor correlation with symptom profile, and lack of evidence that mild OSAS significantly contributes to comorbidity or early mortality. RECENT FINDINGS: Mild obstructive sleep apnoea defined by hourly frequency of apnoeas or hypopnoeas (AHI) between 5 and 15 affects up to 35% of the general adult population but is much less prevalent when associated daytime symptoms are included. The poor correlation between symptoms and AHI complicates diagnosis and reports that mild OSAS is not significantly associated with comorbidity casts doubt on clinical significance. The diagnosis is complicated by night-to-night variability and by underestimation of AHI in ambulatory sleep studies that do not include sleep assessment. Active management of mild OSAS can be symptom-driven and offers a broad range of options. Lifestyle measures may be sufficient in many cases and mandibular advancement devices or positional therapy may be more effective in mild OSAS. Sleepy patients with low AHI may warrant a trial of continuous positive airway pressure therapy to establish the relationship between sleep disordered breathing and symptoms. SUMMARY: Management of mild OSAS can focus on symptom relief to the individual patient.

13 Review COPD-OSA Overlap Syndrome: Evolving Evidence Regarding Epidemiology, Clinical Consequences, and Management. 2017

McNicholas, Walter T. ·Department of Respiratory and Sleep Medicine, St. Vincent's University Hospital, School of Medicine, University College Dublin, Dublin, Ireland. Electronic address: walter.mcnicholas@ucd.ie. ·Chest · Pubmed #28442310.

ABSTRACT: COPD and OSA are both highly prevalent, which implies that both disorders occurring together (overlap syndrome) is likely to be common based on chance association alone. However, different clinical COPD phenotypes influence the likelihood of coexisting OSA in that the increased lung volumes and low BMI associated with the predominant emphysema phenotype protects against OSA, whereas the higher likelihood of peripheral edema and increased BMI associated with the predominant chronic bronchitis phenotype promotes OSA. Both COPD and OSA are associated with similar physiological and molecular consequences, such as hypoxia and systemic inflammation, that contribute to cardiovascular and other comorbidities, and pulmonary hypertension is highly prevalent in patients with the overlap syndrome. However, there have been few published reports that have evaluated systemic inflammation and other cardiovascular comorbidities in patients with overlap syndrome. The diagnosis of OSA in patients with COPD requires awareness of relevant clinical features, and screening questionnaires may help identify suitable patients for further overnight study. The recognition of coexisting OSA in patients with COPD has important clinical relevance, as the management of patients with overlap syndrome is different from the management of COPD alone, and the survival of patients with overlap syndrome that is not treated with nocturnal positive airway pressure is significantly inferior to that of patients with overlap syndrome that is appropriately treated.

14 Review Mild obstructive sleep apnoea: clinical relevance and approaches to management. 2016

McNicholas, Walter T / Bonsignore, Maria R / Lévy, Patrick / Ryan, Silke. ·Department of Respiratory and Sleep Medicine, St Vincent's University Hospital, Dublin, Ireland; School of Medicine and Medical Science, University College Dublin, Dublin, Ireland. Electronic address: walter.mcnicholas@ucd.ie. · DiBiMIS, University of Palermo, Palermo, Italy; CNR Institute of Biomedicine and Molecular Immunology (IBIM), Palermo, Italy. · Univ Grenoble Alpes, Inserm U1042, and Grenoble University Hospital, Grenoble, France. · Department of Respiratory and Sleep Medicine, St Vincent's University Hospital, Dublin, Ireland; School of Medicine and Medical Science, University College Dublin, Dublin, Ireland. ·Lancet Respir Med · Pubmed #27245915.

ABSTRACT: Obstructive sleep apnoea is highly prevalent in the general population worldwide, especially in its mild form. Clinical manifestations correlate poorly with disease severity measured by the apnoea-hypopnoea index (AHI), which complicates diagnosis. Full polysomnography might be more appropriate to assess suspected mild cases because limited ambulatory diagnostic systems are least accurate in mild disease. Treatment options in mild obstructive sleep apnoea include continuous positive airway pressure (CPAP) and oral appliance therapy, in addition to positional therapy and weight reduction when appropriate. The superior efficacy of CPAP in reducing AHI is offset by greater tolerance of oral appliances, especially in mild disease. Although severe obstructive sleep apnoea is associated with adverse health consequences, including cardiometabolic comorbidities, the association with mild disease is unclear, and reports differ regarding the clinical relevance of mild obstructive sleep apnoea. Improved diagnostic techniques and evidence-based approaches to management in mild obstructive sleep apnoea require further research.

15 Review Obstructive sleep apnoea syndrome. 2015

Lévy, Patrick / Kohler, Malcolm / McNicholas, Walter T / Barbé, Ferran / McEvoy, R Doug / Somers, Virend K / Lavie, Lena / Pépin, Jean-Louis. ·Grenoble University Hospital, Department of Physiology, Sleep Laboratory, BP 53, 38041 Grenoble, Cedex 9, France. · Hypoxia-Pathophysiology Laboratory (HP2), University Grenoble Alpes, Grenoble, France. · Department of Pulmonology, University Hospital of Zurich, Zurich, Switzerland. · Pulmonary and Sleep Disorders Unit, University College Dublin, Dublin, Ireland. · Respiratory Department, Arnau de Vilanova and Santa Maria University Hospital, Leida, Spain. · Respiratory Research Group, CIBERES, Madrid, Spain. · Adelaide Institute for Sleep Health, Adelaide, Australia. · Division of Cardiovascular Diseases, Mayo Clinic College of Medicine, Rochester, Minnesota, USA. · The Rappaport Faculty of Medicine, Unit of Anatomy and Cell Biology, Technion - Israel Institute of Technology, Haifa, Israel. ·Nat Rev Dis Primers · Pubmed #27188535.

ABSTRACT: Obstructive sleep apnoea syndrome (OSAS) is a common clinical condition in which the throat narrows or collapses repeatedly during sleep, causing obstructive sleep apnoea events. The syndrome is particularly prevalent in middle-aged and older adults. The mechanism by which the upper airway collapses is not fully understood but is multifactorial and includes obesity, craniofacial changes, alteration in upper airway muscle function, pharyngeal neuropathy and fluid shift towards the neck. The direct consequences of the collapse are intermittent hypoxia and hypercapnia, recurrent arousals and increase in respiratory efforts, leading to secondary sympathetic activation, oxidative stress and systemic inflammation. Excessive daytime sleepiness is a burden for the majority of patients. OSAS is also associated with cardiovascular co-morbidities, including hypertension, arrhythmias, stroke, coronary heart disease, atherosclerosis and overall increased cardiovascular mortality, as well as metabolic dysfunction. Whether treating sleep apnoea can fully reverse its chronic consequences remains to be established in adequately designed studies. Continuous positive airway pressure (CPAP) is the primary treatment modality in patients with severe OSAS, whereas oral appliances are also widely used in mild to moderate forms. Finally, combining different treatment modalities such as CPAP and weight control is beneficial, but need to be evaluated in randomized controlled trials. For an illustrated summary of this Primer, visit: http://go.nature.com/Lwc6te.

16 Review Sleep apnoea and driving risk: the need for regulation. 2015

McNicholas, Walter T / Rodenstein, Daniel. ·Dept of Respiratory and Sleep Medicine, St Vincent's University Hospital, School of Medicine and Medical Science, Conway Institute, University College Dublin, Dublin, Ireland walter.mcnicholas@ucd.ie. · Université Catholique de Louvain, Louvain, Belgium. ·Eur Respir Rev · Pubmed #26621974.

ABSTRACT: Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent chronic respiratory disorder with prevalence among adult males of ≥10%. The most common daytime symptom associated with OSAS is excessive sleepiness, which in more severe manifestations can result in sleepiness at the wheel while driving and probably contributes to the substantial increase in accident risk among patients with OSAS. Fortunately, current evidence indicates that successful therapy of OSAS, particularly with continuous positive airway pressure, can bring the accident risk down to levels similar to an equivalent general population. The recognition of the increased driving accident risk in OSAS prompted the Transport and Mobility Directorate of the European Commission to establish a working group on this topic in 2012, which ultimately led to a revision of Annex III of the EU Driving Licence Directive, which is subject to mandatory implementation by European Union member states by December 2015. This directive specifies that patients with moderate or severe OSAS associated with significant daytime sleepiness should be prohibited from driving until effective therapy is established. These new regulations are designed to balance the legitimate objective of public safety with not penalising OSAS patients who are complying with effective therapy. Successful implementation of regulations on driving in OSAS patients must also include measures to educate relevant stakeholders including patients, medical personnel, traffic police and employers in the transport industry. The key objective is to encourage patients with possible OSAS to seek diagnosis and treatment and not to inhibit OSAS patients from coming forward.

17 Review Obesity and sleep-disordered breathing--when two 'bad guys' meet. 2014

Ryan, S / Crinion, S J / McNicholas, W T. ·From the Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland and School of Medicine and Medical Science, The Conway Institute, University College Dublin, Dublin, Ireland From the Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland and School of Medicine and Medical Science, The Conway Institute, University College Dublin, Dublin, Ireland. · From the Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland and School of Medicine and Medical Science, The Conway Institute, University College Dublin, Dublin, Ireland From the Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland and School of Medicine and Medical Science, The Conway Institute, University College Dublin, Dublin, Ireland walter.mcnicholas@ucd.ie. ·QJM · Pubmed #24509235.

ABSTRACT: Sleep-disordered breathing (SDB), in particular obstructive sleep apnoea (OSA) and obesity hypoventilation syndrome (OHS) are associated with significant morbidity and mortality. The prevalence of these conditions is rapidly rising mainly due to the worldwide increase in obesity. Obesity contributes to the pathogenesis of SDB in multiple ways including altering upper airway anatomy and collapsibility, ventilatory control and increasing respiratory work load. There is also increasing evidence that OSA itself contributes to the development of obesity. Moreover, both OSA and obesity promote the activation of inflammatory pathways, which is likely a key mechanism in cardiovascular and metabolic disease processes. Early recognition of SDB is important as effective treatments are available. Public health measures to reduce the prevalence of obesity are urgently required to halt the increasing burden of SDB.

18 Review Respiratory mechanics and ventilatory control in overlap syndrome and obesity hypoventilation. 2013

Verbraecken, Johan / McNicholas, Walter T. ·Department of Pulmonary Medicine and Multidisciplinary Sleep Disorders Centre, Antwerp University Hospital and University of Antwerp, Wilrijkstraat 10, Edegem 2650, Belgium. johan.verbraecken@uza.be. ·Respir Res · Pubmed #24256627.

ABSTRACT: The overlap syndrome of obstructive sleep apnoea (OSA) and chronic obstructive pulmonary disease (COPD), in addition to obesity hypoventilation syndrome, represents growing health concerns, owing to the worldwide COPD and obesity epidemics and related co-morbidities. These disorders constitute the end points of a spectrum with distinct yet interrelated mechanisms that lead to a considerable health burden. The coexistence OSA and COPD seems to occur by chance, but the combination can contribute to worsened symptoms and oxygen desaturation at night, leading to disrupted sleep architecture and decreased sleep quality. Alveolar hypoventilation, ventilation-perfusion mismatch and intermittent hypercapnic events resulting from apneas and hypopneas contribute to the final clinical picture, which is quite different from the "usual" COPD. Obesity hypoventilation has emerged as a relatively common cause of chronic hypercapnic respiratory failure. Its pathophysiology results from complex interactions, among which are respiratory mechanics, ventilatory control, sleep-disordered breathing and neurohormonal disturbances, such as leptin resistance, each of which contributes to varying degrees in individual patients to the development of obesity hypoventilation. This respiratory embarrassment takes place when compensatory mechanisms like increased drive cannot be maintained or become overwhelmed. Although a unifying concept for the pathogenesis of both disorders is lacking, it seems that these patients are in a vicious cycle. This review outlines the major pathophysiological mechanisms believed to contribute to the development of these specific clinical entities. Knowledge of shared mechanisms in the overlap syndrome and obesity hypoventilation may help to identify these patients and guide therapy.

19 Review Adipose tissue in obesity and obstructive sleep apnoea. 2012

Bonsignore, M R / McNicholas, W T / Montserrat, J M / Eckel, J. ·Biomedical Dept of Internal and Specialistic Medicine, Section of Pneumology, University of Palermo, Palermo, Italy. marisa@ibim.cnr.it ·Eur Respir J · Pubmed #21920888.

ABSTRACT: A European Respiratory Society research seminar on "Metabolic alterations in obstructive sleep apnoea (OSA)" was jointly organised in October 2009 together with two EU COST actions (Cardiovascular risk in the obstructive sleep apnoea syndrome, action B26, and Adipose tissue and the metabolic syndrome, action BM0602) in order to discuss the interactions between obesity and OSA. Such interactions can be particularly significant in the pathogenesis of metabolic abnormalities and in increased cardiovascular risk in OSA patients. However, studying the respective role of OSA and obesity is difficult in patients, making it necessary to refer to animal models or in vitro systems. Since most OSA patients are obese, their management requires a multidisciplinary approach. This review summarises some aspects of the pathophysiology and treatment of obesity, and the possible effects of sleep loss on metabolism. OSA-associated metabolic dysfunction (insulin resistance, liver dysfunction and atherogenic dyslipidaemia) is discussed from the perspective of both obesity and OSA in adults and children. Finally, the effects of treatment for obesity or OSA, or both, on cardio-metabolic variables are summarised. Further interdisciplinary research is needed in order to develop new comprehensive treatment approaches aimed at reducing sleep disordered breathing, obesity and cardiovascular risk.

20 Review Obstructive sleep apnea and inflammation: relationship to cardiovascular co-morbidity. 2011

Kent, Brian D / Ryan, Silke / McNicholas, Walter T. ·Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland. ·Respir Physiol Neurobiol · Pubmed #21439407.

ABSTRACT: Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent disease and associated with cardiovascular morbidity and mortality. The pathogenesis of cardiovascular complications in OSAS is incompletely understood but a multifactorial etiology is likely. There is emerging evidence that inflammatory processes leading to endothelial dysfunction play a pivotal role. Various studies have demonstrated elevated inflammatory markers in OSAS patients in comparison to matched control subjects with a significant fall after effective treatment with continuous positive airway pressure. Cell culture and animal studies have significantly enhanced our understanding of the mechanisms of inflammation in OSAS. Intermittent hypoxia, the hallmark feature of OSAS, leads to a preferential activation of inflammatory pathways with the downstream consequence of expression of pro-inflammatory cytokines, chemokines and adhesion molecules that may contribute to endothelial dysfunction. Further studies are required to determine the precise role of inflammation in the cardiovascular pathogenesis of OSAS, particularly its interaction with oxidative stress, obesity and metabolic dysfunction.

21 Review Obstructive sleep apnea in chronic obstructive pulmonary disease patients. 2011

Lee, Ruth / McNicholas, Walter T. ·Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland. ·Curr Opin Pulm Med · Pubmed #21169840.

ABSTRACT: PURPOSE OF REVIEW: Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) represent two of the most prevalent chronic respiratory disorders and cardiovascular diseases are major co-morbidities in both. Co-existence of both disorders (overlap syndrome) occurs in 1% of adults and overlap patients have worse nocturnal hypoxemia and hypercapnia than COPD and OSA patients alone. The present review discusses recent data concerning the pathophysiological and clinical significance of the overlap syndrome. RECENT FINDINGS: The severity of obstructive ventilatory impairment and hyperinflation, especially the inspiratory capacity to total lung capacity (TLC) ratio, correlates with the severity of sleep-related breathing disturbances. Early treatment with continuous positive airway pressure (CPAP) improves survival, reduces hospitalization and pulmonary hypertension, and also reduces hypoxemia. Evidence of systemic inflammation and oxidative stress in COPD and sleep apnea provides insight into potential interactions between both disorders that may predispose to cardiovascular disease. Long-term outcome studies of overlap patients currently underway should provide further evidence of the clinical significance of the overlap syndrome. SUMMARY: Studies of overlap syndrome patients at a clinical, physiological and molecular level should provide insight into disease mechanisms and consequences of COPD and sleep apnea, in addition to identifying potential relationships with cardiovascular disease.

22 Review The genetics of obstructive sleep apnoea. 2010

Kent, Brian D / Ryan, Silke / McNicholas, Walter T. ·Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland. ·Curr Opin Pulm Med · Pubmed #20814305.

ABSTRACT: PURPOSE OF REVIEW: Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent disorder associated with reduced quality of life and adverse cardiovascular and metabolic sequelae. Recent years have seen an intensification of the research effort to establish the genetic contribution to the development of OSAS and its sequelae. This review explores emerging evidence in this field. RECENT FINDINGS: A genetic basis for sleep-disordered breathing has been demonstrated for discrete disorders such as Treacher-Collins and Down syndromes, but the picture is less clear in so-called idiopathic OSAS. A degree of heritability appears likely in some of the intermediate phenotypes that lead to OSAS, particularly craniofacial morphology. However, only sparse and often contradictory evidence exists regarding the role of specific polymorphisms in causing OSAS in the general population. Similarly, investigations of the cardiovascular sequelae of OSAS have in general failed to consistently find single causative genetic mutations. Nonetheless, evidence suggests a role for tumour necrosis factor-α polymorphisms in particular, and large-scale family studies have suggested shared pathogenetic pathways for the development of obesity and OSAS. SUMMARY: As with other common disorders, OSAS is likely to result from multiple gene-gene interactions occurring in a suitable environment. The application of modern genetic investigative techniques, such as genome-wide association studies, may facilitate new discoveries in this field.

23 Review Continuous positive airway pressure therapy: new generations. 2010

Garvey, John F / McNicholas, Walter T. ·Sleep Research Laboratory, St. Vincent's University Hospital, Dublin, Ireland. john.garvey@ucd.ie ·Indian J Med Res · Pubmed #20308751.

ABSTRACT: Continuous positive airway pressure (CPAP) is the treatment of choice for obstructive sleep apnoea syndrome (OSAS). However, CPAP is not tolerated by all patients with OSAS and alternative modes of pressure delivery have been developed to overcome pressure intolerance, thereby improving patient comfort and adherence. Auto-adjustable positive airway pressure (APAP) devices may be utilised for the long-term management of OSAS and may also assist in the initial diagnosis of OSAS and titration of conventional CPAP therapy. Newer modalities such as C-Flex and A-Flex also show promise as treatment options in the future. However, the evidence supporting the use of these alternative modalities remains scant, in particular with regard to long-term cardiovascular outcomes. In addition, not all APAP devices use the same technological algorithms and data supporting individual APAP devices cannot be extrapolated to support all. Further studies are required to validate the roles of APAP, C-Flex and A-Flex. In the interim, standard CPAP therapy should continue as the mainstay of OSAS management.

24 Clinical Trial Invariant Natural Killer T Cell Deficiency and Functional Impairment in Sleep Apnea: Links to Cancer Comorbidity. 2015

Gaoatswe, Gadintshware / Kent, Brian D / Corrigan, Michelle A / Nolan, Geraldine / Hogan, Andrew E / McNicholas, Walter T / O'Shea, Donal. ·Obesity Immunology Group, Education & Research Center, St Vincent's University Hospital, University College Dublin, Dublin, Ireland. · Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, and School of Medicine and Medical Sciences, University College Dublin, Dublin, Ireland. · Obesity Immunology Group, National Children's Research Center, Dublin, Ireland. ·Sleep · Pubmed #26414901.

ABSTRACT: STUDY OBJECTIVES: Emerging evidence links obstructive sleep apnea (OSA) with increased cancer incidence and mortality. Invariant natural killer T (iNKT) cells play an important role in cancer immunity. We hypothesized that patients with OSA have low number of circulating invariant natural killer T (iNKT) cells, which may also be functionally impaired. This study aims to evaluate the frequency of circulating iNKT cells in OSA. DESIGN: We evaluated the frequency of circulating iNKT cells by flow cytometry in 33 snorers being assessed for possible OSA. Using iNKT cell lines, we also evaluated the effect of exposure to hypoxia over 24 hours on apoptosis, cytotoxicity, and cytokine production. SETTING: Teaching hospital based sleep unit and research laboratory. PATIENTS: Thirty-three snorers were evaluated: 9 with no OSA (apnea-hypopnea frequency [AHI] < 5/h), 12 with mild-moderate OSA (AHI 5-30) and 12 with severe OSA (AHI > 30). MEASUREMENTS AND RESULTS: Patients with severe OSA had considerably fewer iNKT cells (0.18%) compared to patients with mild-moderate (0.24%) or no OSA (0.35%), P = 0.0026. The frequency of iNKT cells correlated negatively with apnea-hypopnea index (r = -0.58, P = 0.001), oxygen desaturation index (r = -0.58, P = 0.0003), and SpO2% < 90% (r = -0.5407, P = 0.005). The frequency of iNKT cells increased following 12 months of nCPAP therapy (P = 0.015). Hypoxia resulted in increased apoptosis (P = 0.016) and impaired cytotoxicity (P = 0.035). CONCLUSION: Patients with obstructive sleep apnea (OSA) have significantly reduced levels of circulating invariant natural killer T (iNKT) cells and hypoxia leads to impaired iNKT cell function. These observations may partly explain the increased cancer risk reported in patients with OSA.

25 Clinical Trial Comparison of a novel non-contact biomotion sensor with wrist actigraphy in estimating sleep quality in patients with obstructive sleep apnoea. 2014

Pallin, Michael / O'Hare, Emer / Zaffaroni, Alberto / Boyle, Patricia / Fagan, Ciara / Kent, Brian / Heneghan, Conor / de Chazal, Philip / McNicholas, Walter T. ·The Respiratory Sleep Disorders Unit, St Vincent's University Healthcare Group, Dublin 4, Ireland. ·J Sleep Res · Pubmed #24495222.

ABSTRACT: Ambulatory monitoring is of major clinical interest in the diagnosis of obstructive sleep apnoea syndrome. We compared a novel non-contact biomotion sensor, which provides an estimate of both sleep time and sleep-disordered breathing, with wrist actigraphy in the assessment of total sleep time in adult humans suspected of obstructive sleep apnoea syndrome. Both systems were simultaneously evaluated against polysomnography in 103 patients undergoing assessment for obstructive sleep apnoea syndrome in a hospital-based sleep laboratory (84 male, aged 55 ± 14 years and apnoea-hypopnoea index 21 ± 23). The biomotion sensor demonstrated similar accuracy to wrist actigraphy for sleep/wake determination (77.3%: biomotion; 76.5%: actigraphy), and the biomotion sensor demonstrated higher specificity (52%: biomotion; 34%: actigraphy) and lower sensitivity (86%: biomotion; 94%: actigraphy). Notably, total sleep time estimation by the biomotion sensor was superior to actigraphy (average overestimate of 10 versus 57 min), especially at a higher apnoea-hypopnoea index. In post hoc analyses, we assessed the improved apnoea-hypopnoea index accuracy gained by combining respiratory measurements from polysomnography for total recording time (equivalent to respiratory polygraphy) with total sleep time derived from actigraphy or the biomotion sensor. Here, the number of misclassifications of obstructive sleep apnoea severity compared with full polysomnography was reduced from 10/103 (for total respiratory recording time alone) to 7/103 and 4/103 (for actigraphy and biomotion sensor total sleep time estimate, respectively). We conclude that the biomotion sensor provides a viable alternative to actigraphy for sleep estimation in the assessment of obstructive sleep apnoea syndrome. As a non-contact device, it is suited to longitudinal assessment of sleep, which could also be combined with polygraphy in ambulatory studies.

Next