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European Respiratory Review : An... Jan 2024Recent scientific findings in the field of sleep disordered breathing have characterised a variety of phenotypes in obstructive sleep apnoea. These findings have... (Review)
Review
Recent scientific findings in the field of sleep disordered breathing have characterised a variety of phenotypes in obstructive sleep apnoea. These findings have prompted investigations aiming to achieve a more precise differentiation and description of the entities of central sleep apnoea (CSA). There is increasing evidence for the heterogeneity of CSA in terms of underlying aetiology, pathophysiological concepts, treatment response and outcome. Assigning patients to these phenotypes allows for the selection of individualised therapies. Major pathophysiological characteristics include loop gain, apnoeic threshold, breathing regulation and neuromuscular mechanics. Chronic heart failure is the most important underlying disease, leading to nonhypercapnic CSA based on increased loop and controller gain. Although many questions remain, this review tries to describe the current knowledge on the pathophysiology of the clinical entities. The description of prognostic aspects may guide treatment indication and the selection of pharmacotherapy and invasive options. In addition, the paper provides an update on the current understanding of adaptive servo-ventilation and its role in the treatment of CSA.
Topics: Humans; Sleep Apnea, Central; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Respiration; Continuous Positive Airway Pressure; Heart Failure
PubMed: 38537948
DOI: 10.1183/16000617.0141-2023 -
Stroke and Vascular Neurology Dec 2016Sleep disorders have been known to physicians for a long time. In his famous aphorisms, Hippocrates said "Sleep or watchfulness exceeding that which is customary, augurs... (Review)
Review
Sleep disorders have been known to physicians for a long time. In his famous aphorisms, Hippocrates said "Sleep or watchfulness exceeding that which is customary, augurs unfavorably". Modern medicine has been able to disentangle some of the phenomena that disturb sleep. Among the most notable offenders is sleep apnoea that has gained prominence in the past few decades. It is being proposed as one of the potentially modifiable risk factors for vascular diseases including stroke. The pathological mechanisms linking sleep apnoea to vascular risk factors include hypoxia, cardiac arrhythmias, dysautonomia, impaired glucose tolerance, hypertension, dyslipidaemia and inflammation. In this article, we review literature linking sleep apnoea and stroke, including sleep apnoea as a risk factor for primary prevention with the potential to improve outcome after acute stroke and as a secondary risk factor, amenable to modification and hence vascular risk reduction.
Topics: Autonomic Nervous System; Humans; Lung; Primary Prevention; Respiration; Risk Assessment; Risk Factors; Secondary Prevention; Sleep; Sleep Apnea Syndromes; Stroke
PubMed: 28959482
DOI: 10.1136/svn-2016-000038 -
Paediatric Anaesthesia Jul 2020Infantile hypertrophic pyloric stenosis (IHPS) leads to excessive vomiting and metabolic alkalosis, which may subsequently cause apnea. Although it is generally assumed... (Review)
Review
BACKGROUND
Infantile hypertrophic pyloric stenosis (IHPS) leads to excessive vomiting and metabolic alkalosis, which may subsequently cause apnea. Although it is generally assumed that metabolic derangements should be corrected prior to surgery to prevent apnea, the exact incidence of perioperative apneas in infants with IHPS and the association with metabolic alkalosis are unknown. We performed this systematic review to assess the incidence of apnea in infants with IHPS and to verify the possible association between apnea and metabolic alkalosis.
METHODS
We searched MEDLINE, Embase, and Cochrane library to identify studies regarding infants with metabolic alkalosis, respiratory problems, and hypertrophic pyloric stenosis. We conducted a descriptive synthesis of the findings of the included studies.
RESULTS
Thirteen studies were included for analysis. Six studies described preoperative apnea, three studies described postoperative apnea, and four studies described both. All studies were of low quality or had other research questions. We found an incidence of 27% of preoperative and 0.2%-16% of postoperative apnea, respectively. None of the studies examined the association between apnea and metabolic alkalosis in infants with IHPS.
CONCLUSIONS
Infants with IHPS may have a risk to develop perioperative apnea. However, the incidence rates should be interpreted with caution because of the low quality and quantity of the studies. Therefore, further studies are required to determine the incidence of perioperative apnea in infants with IHPS. The precise underlying mechanism of apnea in these infants is still unknown, and the role of metabolic alkalosis should be further evaluated.
Topics: Apnea; Humans; Incidence; Infant; Pyloric Stenosis, Hypertrophic
PubMed: 32298502
DOI: 10.1111/pan.13879 -
Paediatric Respiratory Reviews Apr 2020Sleep-disordered breathing (SDB) is associated with neurocognitive and behavioral dysfunction, and structural brain abnormalities. Near infrared spectroscopy allows a... (Review)
Review
Sleep-disordered breathing (SDB) is associated with neurocognitive and behavioral dysfunction, and structural brain abnormalities. Near infrared spectroscopy allows a continuous and non-invasive monitoring of brain tissue oxygenation, giving insight in some pathophysiological mechanisms potentially associated with SDB-related neurocognitive dysfunction. The present review summarizes the finding of studies describing brain tissue oxygenation in adults and children with SDB. Contrary to adults, mean nocturnal tissue oxygenation index (TOI) during sleep does not seem to be different in children with SDB as compared to healthy controls. During respiratory events such as apnoeas and hypopnoeas, the decrease in TOI precedes the peripheral, systemic desaturation. The decrease in TOI has been shown to be greater during apnoeas as compared to hypopnoeas, during rapid-eye movement sleep as compared to other sleep stages, in younger children as compared to their older counterparts, and in those with a high apnoea-hypopnoea index as compared with a low apnoea-hypopnoea index. Studies analyzing the association between repetitive changes in TOI and neurocognitive and behavioral dysfunction may help to decipher the pathophysiology of neurocognitive dysfunction associated with SDB in children.
Topics: Adult; Age Factors; Brain; Child; Humans; Oxygen; Sleep; Sleep Apnea Syndromes; Sleep Stages; Sleep, REM; Spectroscopy, Near-Infrared
PubMed: 31753753
DOI: 10.1016/j.prrv.2019.10.002 -
The European Respiratory Journal May 2022Heart failure and sleep disordered breathing (SDB) are two common conditions that frequently overlap and have been studied extensively in the past three decades....
Heart failure and sleep disordered breathing (SDB) are two common conditions that frequently overlap and have been studied extensively in the past three decades. Obstructive sleep apnoea (OSA) may result in myocardial damage due to intermittent hypoxia that leads to increased sympathetic activity and transmural pressures, low-grade vascular inflammation, and oxidative stress. On the other hand, central sleep apnoea and Cheyne-Stokes respiration (CSA-CSR) occurs in heart failure, irrespective of ejection fraction, either reduced (HFrEF), preserved (HFpEF) or mildly reduced (HFmrEF). The pathophysiology of CSA-CSR relies on several mechanisms leading to hyperventilation, breathing cessation and periodic breathing. Pharyngeal collapse may result at least in part from fluid accumulation in the neck, owing to daytime fluid retention and overnight rostral fluid shift from the legs. Although both OSA and CSA-CSR occur in heart failure, the symptoms are less suggestive than in typical (non-heart failure-related) OSA. Overnight monitoring is mandatory for a proper diagnosis, with accurate measurement and scoring of central and obstructive events, since the management will be different depending on whether the sleep apnoea in heart failure is predominantly OSA or CSA-CSR. SDB in heart failure is associated with worse prognosis, including higher mortality, than in patients with heart failure but without SDB. However, there is currently no evidence that treating SDB improves clinically important outcomes in patients with heart failure, such as cardiovascular morbidity and mortality.
Topics: Cheyne-Stokes Respiration; Heart Failure; Humans; Polysomnography; Sleep Apnea Syndromes; Sleep Apnea, Central; Sleep Apnea, Obstructive; Stroke Volume
PubMed: 34949696
DOI: 10.1183/13993003.01640-2021 -
The Canadian Journal of Cardiology May 2021Patients with obstructive sleep apnea (OSA) experience repetitive partial or complete airway collapse during sleep resulting in nocturnal hypoxia-normoxia cycling, and... (Review)
Review
Patients with obstructive sleep apnea (OSA) experience repetitive partial or complete airway collapse during sleep resulting in nocturnal hypoxia-normoxia cycling, and are at increased cardiovascular risk. The number of apneas and hypopneas indexed per hour of sleep (apnea-hypopnea index) along with the associated intermittent hypoxia predict the increased cardiovascular risk; thus, their attenuation or prevention are objectives of OSA therapy. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA and, when effective, mitigates the apnea-hypopnea index and hypoxemia. As such, it is reasonable to expect CPAP would decrease cardiovascular risk. However, 3 recent randomized clinical trials of CPAP vs usual care did not show any significant effects of CPAP in attenuating incident cardiovascular events in patients with OSA. In this review, we discuss these studies in addition to potential complementary therapeutic options to CPAP (eg, neurostimulation) and conclude with suggested therapeutic targets for future interventional studies (eg, the autonomic nervous system). Although these areas of research are exciting, they have yet to be tested to any similar degree of rigour as CPAP.
Topics: Cardiovascular Diseases; Continuous Positive Airway Pressure; Heart Disease Risk Factors; Humans; Sleep Apnea, Obstructive
PubMed: 33610689
DOI: 10.1016/j.cjca.2021.01.027 -
Sleep Aug 2023We aimed to characterize the cerebral hemodynamic response to obstructive sleep apnea/hypopnea events, and evaluate their association to polysomnographic parameters. The...
STUDY OBJECTIVES
We aimed to characterize the cerebral hemodynamic response to obstructive sleep apnea/hypopnea events, and evaluate their association to polysomnographic parameters. The characterization of the cerebral hemodynamics in obstructive sleep apnea (OSA) may add complementary information to further the understanding of the severity of the syndrome beyond the conventional polysomnography.
METHODS
Severe OSA patients were studied during night sleep while monitored by polysomnography. Transcranial, bed-side diffuse correlation spectroscopy (DCS) and frequency-domain near-infrared diffuse correlation spectroscopy (NIRS-DOS) were used to follow microvascular cerebral hemodynamics in the frontal lobes of the cerebral cortex. Changes in cerebral blood flow (CBF), total hemoglobin concentration (THC), and cerebral blood oxygen saturation (StO2) were analyzed.
RESULTS
We considered 3283 obstructive apnea/hypopnea events from sixteen OSA patients (Age (median, interquartile range) 57 (52-64.5); females 25%; AHI (apnea-hypopnea index) 84.4 (76.1-93.7)). A biphasic response (maximum/minimum followed by a minimum/maximum) was observed for each cerebral hemodynamic variable (CBF, THC, StO2), heart rate and peripheral arterial oxygen saturation (SpO2). Changes of the StO2 followed the dynamics of the SpO2, and were out of phase from the THC and CBF. Longer events were associated with larger CBF changes, faster responses and slower recoveries. Moreover, the extrema of the response to obstructive hypopneas were lower compared to apneas (p < .001).
CONCLUSIONS
Obstructive apneas/hypopneas cause profound, periodic changes in cerebral hemodynamics, including periods of hyper- and hypo-perfusion and intermittent cerebral hypoxia. The duration of the events is a strong determinant of the cerebral hemodynamic response, which is more pronounced in apnea than hypopnea events.
Topics: Female; Humans; Sleep Apnea, Obstructive; Hemodynamics; Sleep Apnea Syndromes; Spectroscopy, Near-Infrared; Airway Obstruction
PubMed: 37336476
DOI: 10.1093/sleep/zsad122 -
The European Respiratory Journal Jul 2022Increased mortality has been reported in people with insomnia and in those with obstructive sleep apnoea (OSA). However, these conditions commonly co-occur and the...
BACKGROUND
Increased mortality has been reported in people with insomnia and in those with obstructive sleep apnoea (OSA). However, these conditions commonly co-occur and the combined effect of comorbid insomnia and sleep apnoea (COMISA) on mortality risk is unknown. This study used Sleep Heart Health Study (SHHS) data to assess associations between COMISA and all-cause mortality risk.
METHODS
Insomnia was defined as difficulties falling asleep, maintaining sleep and/or early morning awakenings from sleep ≥16 times per month, and daytime impairments. OSA was defined as an apnoea-hypopnoea index ≥15 events·h. COMISA was defined if both conditions were present. Multivariable adjusted Cox proportional hazards models were used to determine the association between COMISA and all-cause mortality (n=1210) over 15 years of follow-up.
RESULTS
5236 participants were included. 2708 (52%) did not have insomnia/OSA (reference group), 170 (3%) had insomnia-alone, 2221 (42%) had OSA-alone and 137 (3%) had COMISA. COMISA participants had a higher prevalence of hypertension (OR 2.00, 95% CI 1.39-2.90) and cardiovascular disease (CVD) (OR 1.70, 95% CI 1.11-2.61) compared with the reference group. Insomnia-alone and OSA-alone were associated with higher risk of hypertension but not CVD compared with the reference group. Compared with the reference group, COMISA was associated with a 47% (hazard ratio 1.47, 95% CI 1.06-2.07) increased risk of mortality. The association between COMISA and mortality was consistent across multiple definitions of OSA and insomnia.
CONCLUSIONS
COMISA was associated with higher rates of hypertension and CVD at baseline, and an increased risk of all-cause mortality compared with no insomnia/OSA.
Topics: Cardiovascular Diseases; Humans; Hypertension; Polysomnography; Sleep; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Sleep Initiation and Maintenance Disorders
PubMed: 34857613
DOI: 10.1183/13993003.01958-2021 -
European Journal of Heart Failure Apr 2016Sleep-disordered breathing-comprising obstructive sleep apnoea (OSA), central sleep apnoea (CSA), or a combination of the two-is found in over half of heart failure (HF)... (Review)
Review
Sleep-disordered breathing-comprising obstructive sleep apnoea (OSA), central sleep apnoea (CSA), or a combination of the two-is found in over half of heart failure (HF) patients and may have harmful effects on cardiac function, with swings in intrathoracic pressure (and therefore preload and afterload), blood pressure, sympathetic activity, and repetitive hypoxaemia. It is associated with reduced health-related quality of life, higher healthcare utilization, and a poor prognosis. Whilst continuous positive airway pressure (CPAP) is the treatment of choice for patients with daytime sleepiness due to OSA, the optimal management of CSA remains uncertain. There is much circumstantial evidence that the treatment of OSA in HF patients with CPAP can improve symptoms, cardiac function, biomarkers of cardiovascular disease, and quality of life, but the quality of evidence for an improvement in mortality is weak. For systolic HF patients with CSA, the CANPAP trial did not demonstrate an overall survival or hospitalization advantage for CPAP. A minute ventilation-targeted positive airway therapy, adaptive servoventilation (ASV), can control CSA and improves several surrogate markers of cardiovascular outcome, but in the recently published SERVE-HF randomized trial, ASV was associated with significantly increased mortality and no improvement in HF hospitalization or quality of life. Further research is needed to clarify the therapeutic rationale for the treatment of CSA in HF. Cardiologists should have a high index of suspicion for sleep-disordered breathing in those with HF, and work closely with sleep physicians to optimize patient management.
Topics: Atrial Fibrillation; Continuous Positive Airway Pressure; Health Services; Heart; Heart Failure; Heart Failure, Systolic; Hospitalization; Humans; Inflammation; Myocardial Ischemia; Positive-Pressure Respiration; Pressure; Prognosis; Quality of Life; Reactive Oxygen Species; Sleep Apnea Syndromes; Sleep Apnea, Central; Sleep Apnea, Obstructive; Survival Rate; Sympathetic Nervous System; Thoracic Cavity
PubMed: 26869027
DOI: 10.1002/ejhf.492 -
Respirology (Carlton, Vic.) Jul 2017P4 medicine is an evolving approach to personalized medicine. The four Ps offer a means to: Predict who will develop disease and co-morbidities; Prevent rather than... (Review)
Review
P4 medicine is an evolving approach to personalized medicine. The four Ps offer a means to: Predict who will develop disease and co-morbidities; Prevent rather than react to disease; Personalize diagnosis and treatment; have patients Participate in their own care. P4 medicine is very applicable to obstructive sleep apnoea (OSA) because each OSA patient has a different pathway to disease and its consequences. OSA has both structural and physiological mechanisms with different clinical subgroups, different molecular profiles and different consequences. This may explain why there are different responses to alternative therapies, such as intraoral devices and hypoglossal nerve stimulation therapy. Currently, technology facilitates patients to participate in their own care from screening for OSA (snoring and apnoea apps) to monitoring response to therapy (sleep monitoring, blood pressure, oxygen saturation and heart rate) as well as monitoring their own continuous positive airway pressure (CPAP) compliance. We present a conceptual framework that provides the basis for a new, P4 medicine approach to OSA and should be considered more in depth: predict and prevent those at high risk for OSA and consequences, personalize the diagnosis and treatment of OSA and build in patient participation to manage OSA.
Topics: Continuous Positive Airway Pressure; Humans; Patient Compliance; Patient Participation; Precision Medicine; Primary Prevention; Risk Assessment; Sleep Apnea, Obstructive
PubMed: 28477347
DOI: 10.1111/resp.13063