Arterial stiffness and endothelial function in obstructive sleep apnoea: the effect of Continuous Positive Airway Pressure (CPAP) therapy

Introduction: Obstructive sleep apnoea (OSA) is common and is caused by repetitive obstruction of the upper airway during sleep. OSA is associated with increased cardiovascular morbidity and mortality and is an independent risk factor for hypertension. The immediate physiological effects of OSA include intermittent hypoxia, repeated arousal from sleep and intra-thoracic pressure swings. The resulting activation of the sympathetic nervous system, systemic inflammation and oxidative stress may result in increased arterial stiffness and endothelial dysfunction, potentially explaining any causal link between OSA and cardiovascular disease (CVD). Continuous positive airway pressure (CPAP) therapy improves excessive daytime sleepiness (EDS) and in non-randomised studies, reduces cardiovascular mortality. Prior to starting this study, there was a limited amount of evidence suggesting that CPAP therapy improved arterial stiffness and endothelial function, but the effects in subjects without pre-existing CVD were unclear. Aims: i) to determine whether CPAP therapy has an effect upon measures of arterial stiffness and endothelial function in patients with OSA, in the absence of known CVD. ii) To compare arterial stiffness and endothelial function in a subset of patients with OSAHS (defined as OSA and EDS), with a group of well-matched control subjects. Methods: Fifty three patients with OSA, defined as an apnoea/hypopnoea index of ≥15, and without known CVD, entered a double-blind placebo-controlled crossover trial of 12 weeks CPAP therapy, of whom forty three completed the study protocol. Sham CPAP was used in the placebo arm of the study and vascular assessments were made at baseline and after each arm of the study. Arterial stiffness was determined by measuring aortic distensibility using cardiovascular magnetic resonance imaging and by measuring the augmentation index (AIx) and aortic pulse wave velocity (PWV) by applanation tonometry. Endothelial function was assessed non-invasively by measuring vascular reactivity after administration of salbutamol and glyceryl trinitrate. In a subset of twenty patients with OSAHS, arterial stiffness and endothelial function at baseline were compared to readings obtained from healthy control subjects, matched on a one-to-one basis for age, sex and BMI. Results: Patients with OSAHS (n=20) had increased arterial stiffness [AIx 19.3(10.9) vs. 12.6(10.2) %; p=0.017] and impaired endothelial function, measured as the change in AIx following salbutamol [-4.3(3.2) vs. -8.0(4.9) %; p=0.02] compared to controls. Twelve weeks of CPAP therapy had no significant effect upon any measure of arterial stiffness or endothelial function in patients with OSA (n=43). A trend towards a reduction in AIx following CPAP therapy was seen, but this was non-significant. There was a reduction in systolic blood pressure following CPAP therapy [126(12) vs. 129(14) mmHg]. Sub group analysis showed CPAP to have no effect on arterial stiffness or endothelial function in patients with EDS or in patients using CPAP for ≥4 hours per night. Conclusions: This study demonstrates that even in the absence of known CVD, patients with OSAHS have evidence of increased arterial stiffness and impaired endothelial function. However, in patients with OSA, free from CVD, CPAP therapy did not lead to an improvement in any measure of arterial stiffness or endothelial function after 12 weeks

Contrasting Effects of Lower Body Positive Pressure on Upper Airways Resistance and Partial Pressure of Carbon Dioxide in Men With Heart Failure and Obstructive or Central Sleep Apnea

ObjectivesThis study sought to test the effects of rostral fluid displacement from the legs on transpharyngeal resistance (Rph), minute volume of ventilation (Vmin), and partial pressure of carbon dioxide (PCO2) in men with heart failure (HF) and either obstructive (OSA) or central sleep apnea (CSA).BackgroundOvernight rostral fluid shift relates to severity of OSA and CSA in men with HF. Rostral fluid displacement may facilitate OSA if it shifts into the neck and increases Rph, because pharyngeal obstruction causes OSA. Rostral fluid displacement may also facilitate CSA if it shifts into the lungs and induces reflex augmentation of ventilation and reduces PCO2, because a decrease in PCO2 below the apnea threshold causes CSA.MethodsMen with HF were divided into those with mainly OSA (obstructive-dominant, n = 18) and those with mainly CSA (central-dominant, n = 10). While patients were supine, antishock trousers were deflated (control) or inflated for 15 min (lower body positive pressure [LBPP]) in random order.ResultsLBPP reduced leg fluid volume and increased neck circumference in both obstructive- and central-dominant groups. However, in contrast to the obstructive-dominant group in whom LBPP induced an increase in Rph, a decrease in Vmin, and an increase in PCO2, in the central-dominant group, LBPP induced a reduction in Rph, an increase in Vmin, and a reduction in PCO2.ConclusionsThese findings suggest mechanisms by which rostral fluid shift contributes to the pathogenesis of OSA and CSA in men with HF. Rostral fluid shift could facilitate OSA if it induces pharyngeal obstruction, but could also facilitate CSA if it augments ventilation and lowers PCO2

Srčano-plućne interakcije s posljedičnim plućnim abnormalnostima u bolesnika s kroničnim srčanim zatajenjem

Chronic heart failure places heavy burden on patients, their families and on health care resources, accounting for high numbers of hospital admissions. Despite huge improvements in the treatment of many heart disorders, the clinical syndrome of chronic heart failure as a fi nal pathway of heart pathology is an exception, in that its prevalence is rising, and only small prolongations in survival are occurring. It is associated with high morbidity and poor prognosis, and a survival rate worse than that for some malignant tumors. Th e reasons for the increasing overall prevalence of chronic heart failure in developed countries lie in prolonged survival owing to modern pharmacological or invasive treatment, better secondary prevention, and aging of the population. Chronic pulmonary disease is common in patients with chronic heart failure. Th rough sharing some risk factors and overlapping pathophysiological processes, they present diagnostic and therapeutic challenge. Th e aim of this article is to review various mechanisms responsible for the symptoms of chronic heart failure with consecutive pulmonary interaction and abnormalities in lung function.Kronično srčano zatajenje značajno opterećuje bolesnika i njegovu obitelj kao i zdravstveni sustav u cjelini budući da je odgovorno za velik broj hospitalizacija. Unatoč golemim naporima u liječenju većine srčanih poremećaja iznimka ostaje klinički sindrom kroničnog srčanog zatajenja učestalost kojega raste s neznatnim uspjehom produženja ukupnog preživljenja bolesnika. Kronično srčano zatajenje je povezano s visokom stopom pobola te nepovoljnom prognozom, čak lošijom uspoređujući sa stopom preživljenja za neke vrste zloćudnih tumora. Razlog porasta učestalosti kroničnog srčanog zatajenja u razvijenim zemljama je produljenje ljudskog vijeka zahvaljujući mjerama suvremenog farmakološkog i intenzivnog liječenja, boljoj sekundarnoj profi laksi i starenju populacije. Kronična plućna bolest je česta pojava u bolesnika s kroničnim srčanim zatajenjem. Oba stanja predstavljaju dijagnostički i terapijski izazov budući da dijele pojedine zajedničke čimbenike rizika i patofi ziološke mehanizme nastanka. Cilj ovoga rada je ispitati različite mehanizme odgovorne za simptome kroničnog srčanog zatajenja s posljedičnim plućnim interakcijama i abnormalnostima plućne funkcije

HRS white paper on clinical utilization of digital health technology.

This collaborative statement from the Digital Health Committee of the Heart Rhythm Society provides everyday clinical scenarios in which wearables may be utilized by patients for cardiovascular health and arrhythmia management. We describe herein the spectrum of wearables that are commercially available for patients, and their benefits, shortcomings and areas for technological improvement. Although wearables for rhythm diagnosis and management have not been examined in large randomized clinical trials, undoubtedly the usage of wearables has quickly escalated in clinical practice. This document is the first of a planned series in which we will update information on wearables as they are revised and released to consumers

Sleep in patients with type 2 diabetes: the impact of sleep apnoea, sleep duration, and sleep quality on clinical outcomes

Introduction: Type 2 Diabetes (T2DM) and sleep-related disorders share common risk factors such as obesity; but the interrelationships between T2DM and sleep disorders are not well examined. Aims: In this thesis I aimed to assess: 1. The longitudinal impact of obstructive sleep apnoea (OSA) on micro vascular complications in patient with T2DM. 2. The relationship between sleep quality, sleep duration and adiposity in patients with T2DM Methods: To examine the first aim, I utilized the data collected from a previous project that examined the cross-sectional associations between OSA and micro vascular complications in patients with T2DM and followed up the study participants longitudinally using 1-2-1 interviews and electronic health records. For aim 2, I conducted a crosssectional study in patients with young-onset T2DM who were recruited from Heart of England NHS Foundation Trust and primary care. Result: For Aim 1: Depending on the micro vascular outcome examined, we had approximately 200 patients in the analysis. Patients were followed up for 2.5 years for renal outcomes, and 4-4.5 years for retinopathy and neuropathy outcomes. The prevalence of OSA was 63%. I found that baseline OSA was significantly associated with greater decline of eGFR and greater progression to pre-proliferative and proliferative retinopathy. I also found that OSA was associated with progression to a combined outcome of foot insensitivity or diabetic foot ulceration but this was a non-significant trend (p=0.06). In addition, I found that patients who received and were compliant with continuous positive airway pressure (CPAP) treatment (delivered during routine care) had improvements in heart rate variability parameters by study end. For Aim 2: Poor sleep quality and shorter sleep duration were associated with increased total body fat% after adjustment for potential confounders. Conclusion: I found that OSA plays an important role in the progression of micro vascular complications in patients with T2DM. Whether treatment with CPAP has a favourable impact on micro vascular complications is currently being examined in a randomized controlled trial. I also found that sleep duration and quality are associated with increased adiposity. The direction of this relationship need to be examined in longitudinal studies and interventional trials

Remote monitoring of heart failure: benefits for therapeutic decision making

Introduction: Chronic heart failure is a cardiovascular disorder with high prevalence and incidence worldwide. The course of heart failure is characterized by periods of stability and instability. Decompensation of heart failure is associated with frequent and prolonged hospitalizations and it worsens the prognosis for the disease and increases cardiovascular mortality among affected patients. It is therefore important to monitor these patients carefully to reveal changes in their condition. Remote monitoring has been designed to facilitate an early detection of adverse events and to minimize regular follow-up visits for heart failure patients. Several new devices have been developed and introduced to the daily practice of cardiology departments worldwide. Areas covered: Currently, special tools and techniques are available to perform remote monitoring. Concurrently there are a number of modern cardiac implantable electronic devices that incorporate a remote monitoring function. All the techniques that have a remote monitoring function are discussed in this paper in detail. All the major studies on this subject have been selected for review of the recent data on remote monitoring of HF patients and demonstrate the role of remote monitoring in the therapeutic decision making for heart failure patients. Expert commentary: Remote monitoring represents a novel intensified follow-up strategy of heart failure management. Overall, theoretically, remote monitoring may play a crucial role in the early detection of heart failure progression and may improve the outcome of patients

Σύνδρομο υπνικής άπνοιας και πολιτικές πρόληψης ατυχημάτων σε Ευρωπαϊκό επίπεδο

Αντικείμενο-Στόχος: Οι ακούσιες σωματικές κακώσεις αποτελούν προβλέψιμο και προλήψιμο πρόβλημα Δημόσιας Υγείας. Στόχοι ήταν η ανάδειξη των στοιχείων που επηρεάζουν την εφαρμοσιμότητα καλών πρακτικών, η επισήμανση καινοφανών παραγόντων κινδύνου για τροχαία και η σύνοψη ευρημάτων για τη συμβολή της CPAP στη βελτίωση της αρτηριακής δυσκαμψίας σε ασθενείς με σύνδρομο υπνικής άπνοιας (ΣΑΥ). Μεθοδολογία: Αναπτύχθηκε ηλεκτρονικό ερωτηματολόγιο για τη βαθμολόγηση της δυνατότητας μεταφοράς πολιτικών πρόληψης μεταξύ χωρών. Συλλέχθησαν δεδομένα για ΣΑΥ από οδηγούς ταξί και πραγματοποιήθηκε μετα-ανάλυση για το ρόλο της CPAP στην αρτηριακή δυσκαμψία. Αποτελέσματα: Οι πολιτικές πρόληψης πιο πιθανό να μεταφερθούν αφορούν πολυδιάστατες παρεμβάσεις. Ένας στους 4 οδηγούς ταξί εκτιμήθηκε ως υψηλού κινδύνου, αλλά μόνον 22 προσήλθαν για περαιτέρω εξέταση, δεκαεπτά από τους οποίους διαγνώστηκαν με ΣΑΥ. Η έκθεση σε υψηλά επίπεδα άγχους σε συνδυασμό με την προσπάθεια για οικονομική επιβίωση εκτιμήθηκε ως βασική αιτία μη συμμετοχής. Οι δείκτες αρτηριακής δυσκαμψίας φάνηκε να βελτιώνονται σημαντικά με χρήση CPAP. Συμπεράσματα: Κρίθηκε αναγκαία η διάχυση της πληροφορίας για τις διαθέσιμες καλές πρακτικές μείωσης ατυχημάτων. Ιδιαίτερα υψηλή βρέθηκε στη χώρα μας η συχνότητα των οδηγών ταξί σε κίνδυνο για ΣΑΥ. Από βιολογικής πλευράς, η μετα- ανάλυση έδειξε σημαντική βελτίωση όλων των δεικτών αρτηριακής δυσκαμψίας μετά από θεραπεία με CPAP σε ασθενείς με ΣΑΥ.Background-Aim: Unintentional injuries constitute a predictable and preventable Public Health problem. Our study aimed at identifying the encouraging factors and barriers for the implementation of good injury prevention practice, at recognizing new risk factors for road traffic injuries and at summarizing the effect of obstructive sleep apnea (OSA) treatment in improving arterial stiffness in OSA patients. Methodology: An electronic questionnaire was developed for the assessment of injury prevention policy transfer between countries. OSA-related data were collected for taxi drivers and a meta-analysis was performed to assess the effect of OSA treatment on arterial stiffness. Results: Multi-dimensional injury prevention policies were found to be easier to transfer between different countries. One out of 4 taxi drivers was identified as high-risk for OSA, only 22 accepted to be further examined, 17 of whom were diagnosed with the syndrome OSA. Psychological stress in combination with their struggle for economic survival was the main reason for declining screening participation. Arterial stiffness diminished after treatment with CPAP. Conclusions: The diffusion of information regarding available good injury prevention practices was deemed necessary. Taxi drivers in Athens were found to be at high risk for OSA. Our meta-analysis showed improvement of arterial stiffness after treatment with CPAP