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Role of Mineralocorticoid Receptors in Obstructive Sleep Apnea and Metabolic Syndrome. Curr Hypertens Rep 2018; 20:23. [DOI: 10.1007/s11906-018-0819-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Eskandari D, Zou D, Grote L, Hoff E, Hedner J. Acetazolamide Reduces Blood Pressure and Sleep-Disordered Breathing in Patients With Hypertension and Obstructive Sleep Apnea: A Randomized Controlled Trial. J Clin Sleep Med 2018; 14:309-317. [PMID: 29510792 DOI: 10.5664/jcsm.6968] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 10/30/2017] [Indexed: 11/13/2022]
Abstract
STUDY OBJECTIVES The carbonic anhydrase inhibitor acetazolamide (AZT) modulates blood pressure at high altitude and reduces sleep-disordered breathing in patients with obstructive sleep apnea (OSA). We aimed to investigate the treatment effect of AZT and in combination with continuous positive airway pressure (CPAP) on blood pressure in patients with hypertension and OSA. METHODS In a prospective, randomized, three-way crossover study, 13 male patients with hypertension and moderate to severe OSA (age 64 ± 7 years, body mass index 29 ± 4 kg/m2, and mean apnea-hypopnea index 37 ± 23 events/h) received AZT, CPAP, or AZT plus CPAP for 2-week periods. Antihypertensive medication was washed out. Office and 24-hour blood pressure, arterial stiffness, polygraphic sleep study data, and blood chemistry were compared. RESULTS AZT alone and AZT plus CPAP, but not CPAP alone, reduced office mean arterial pressure compared to baseline (-7 [95% CI -11 to -4], -7 [95% CI -11 to -4] and -1 [95% CI -5 to 4] mmHg, respectively; repeated- measures analysis of variance (RM-ANOVA; P = .015). Aortic systolic pressure and augmentation index, assessed by radial artery oscillatory tonometry, were unaffected by CPAP but decreased after AZT and AZT plus CPAP (RM-ANOVA P = .030 and .031, respectively). The apnea-hypopnea index was significantly reduced in all three treatment arms, most prominently by AZT plus CPAP (RM-ANOVA P = .003). The reduction of venous bicarbonate concentration following AZT was correlated with the change of apnea-hypopnea index (r = 0.66, P = .013). CONCLUSIONS AZT reduced blood pressure, vascular stiffness, and sleep-disordered breathing in patients with OSA and comorbid hypertension. Carbonic anhydrase inhibition may constitute a potential target for drug therapy in patients with sleep apnea and comorbid hypertension. CLINICAL TRIAL REGISTRATION Registry: ClinicalTrials.gov; Identifier: NCT02220803; Title: A Short Term Open, Randomized Cross-over Trial Exploring the Effect of Carbonic Anhydrase Inhibition by Acetazolamide on Sleep Apnea Associated Hypertension and Vascular Dysfunction; URL: https://clinicaltrials.gov/ct2/show/NCT02220803 and Registry: EU Clinical Trials Register; EudraCT Number: 2013-004866-33; Title: A short term open, randomized cross over trial exploring the effect of carbonic anhydrase inhibition by acetazolamide on sleep apnea associated hypertension; URL: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-004866-33.
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Affiliation(s)
- Davoud Eskandari
- Center for Sleep and Vigilance Disorders, Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ding Zou
- Center for Sleep and Vigilance Disorders, Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ludger Grote
- Center for Sleep and Vigilance Disorders, Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Sleep Disorders Center, Pulmonary Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Erik Hoff
- Center for Sleep and Vigilance Disorders, Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Sleep Disorders Center, Pulmonary Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Jan Hedner
- Center for Sleep and Vigilance Disorders, Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Sleep Disorders Center, Pulmonary Department, Sahlgrenska University Hospital, Gothenburg, Sweden
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Neuroendocrine and Inflammatory Responses to Losartan and Continuous Positive Airway Pressure in Patients with Hypertension and Obstructive Sleep Apnea. A Randomized Controlled Trial. Ann Am Thorac Soc 2017; 13:2002-2011. [PMID: 27548072 DOI: 10.1513/annalsats.201602-126oc] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RATIONALE Blood pressure reduction in response to antihypertensive agents is less for patients with obstructive sleep apnea (OSA). Increased sympathetic and inflammatory activity, as well as alterations in the renin-angiotensin-aldosterone system, may play a role in this context. OBJECTIVES To address the cardiovascular mechanisms involved in response to an angiotensin II receptor antagonist, losartan, and continuous positive airway pressure (CPAP) as add-on treatment for hypertension and OSA. METHODS Newly diagnosed hypertensive patients with or without OSA (allocated in a 2:1 ratio for OSA vs. no OSA) were treated with losartan 50 mg daily during a 6-week two-center, open-label, prospective, case-control, parallel-design study. In the second 6-week, sex-stratified, open-label, randomized, parallel-design study, all subjects with OSA continued to receive losartan and were randomly assigned to either CPAP as add-on therapy or to no CPAP (1:1 ratio for CPAP vs. no CPAP). Study subjects without OSA were followed in parallel while they continued to take losartan. Blood samples were collected at baseline, after 6 weeks, and after 12 weeks for analysis of renin, aldosterone, noradrenaline, adrenaline, and inflammatory markers. MEASUREMENTS AND MAIN RESULTS Fifty-four patients with OSA and 35 without OSA were included in the first 6-week study. Losartan significantly increased renin levels and reduced aldosterone levels in the group without OSA. There was no significant decrease in aldosterone levels among patients with OSA. Add-on CPAP treatment tended to lower aldosterone levels, but reductions were more pronounced in measures of sympathetic activity. No significant changes in inflammatory markers were observed following treatment with losartan and CPAP. CONCLUSIONS Hypertensive patients with OSA responded to losartan treatment with smaller reductions in aldosterone compared with hypertensive patients without OSA. Sympathetic system activity seemed to respond primarily to add-on CPAP treatment in patients with newly discovered hypertension and OSA. Clinical trial registered with www.clinicaltrials.gov (NCT00701428).
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Gautier-Veyret E, Pépin JL, Stanke-Labesque F. Which place of pharmacological approaches beyond continuous positive airway pressure to treat vascular disease related to obstructive sleep apnea? Pharmacol Ther 2017; 186:45-59. [PMID: 29277633 DOI: 10.1016/j.pharmthera.2017.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Obstructive sleep apnea (OSA) is characterized by recurrent episodes of partial or complete upper airway obstruction, occurring during sleep, leading to chronic intermittent hypoxia (IH), which harms the cardiovascular system. OSA is associated with both functional and structural vascular alterations that contribute to an increased prevalence of fatal and non-fatal cardiovascular events. OSA is a heterogeneous disease with respect to the severity of hypoxia, the presence of daytime symptoms, obesity, and cardiovascular comorbidities. Various clusters of OSA phenotypes have been described leading to more highly personalized treatment. The aim of this review is to describe the various therapeutic strategies including continuous positive airway pressure (CPAP), oral appliances, surgery, weight loss, and especially pharmacological interventions that have been evaluated to reduce vascular alterations in both OSA patients and preclinical animal models. Conventional therapies, predominantly CPAP, have a limited impact on vascular alterations in the presence of co-morbidities. A better knowledge of pharmacological therapies targeting IH-induced vascular alterations will facilitate the use of combined therapies and is crucial for designing clinical trials in well-defined OSA phenotypes.
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Affiliation(s)
- Elodie Gautier-Veyret
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France.
| | - Jean-Louis Pépin
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France
| | - Françoise Stanke-Labesque
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France
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Bhatawadekar SA, Keller G, Francisco CO, Inman MD, Fredberg JJ, Tarlo SM, Stanbrook M, Lyons OD, Yadollahi A. Reduced Baseline Airway Caliber Relates to Larger Airway Sensitivity to Rostral Fluid Shift in Asthma. Front Physiol 2017; 8:1012. [PMID: 29311954 PMCID: PMC5733084 DOI: 10.3389/fphys.2017.01012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/22/2017] [Indexed: 12/04/2022] Open
Abstract
Background: We have previously shown that when asthmatics go supine, fluid shifts out of the legs, accumulates in the thorax, and exacerbates lower airway narrowing. In the retrospective analysis of our previous work presented here, we test the hypothesis that the sensitivity of this process relates inversely to baseline caliber of the lower airways. Methods: Eighteen healthy (six women) and sixteen asthmatic subjects (nine women) sat for 30 min, and then lay supine for 30 min. While supine, lower body positive pressure (LBPP, 40 mm Hg) was applied to displace fluid from the legs similar in amount to the overnight fluid shift. Respiratory resistance and reactance at 5 Hz (R5 and X5) and leg and thoracic fluid volumes (LFV and TFV) were measured at the beginning and end of the supine period. Results: With LBPP, healthy, and asthmatic subjects had similar changes in the LFV and TFV (p = 0.3 and 0.1, respectively). Sensitivity to fluid shift, defined by ΔR5/ΔTFV, was larger in the asthmatics than in the healthy subjects (p = 0.0001), and correlated with baseline R5 in the supine position in the asthmatics (p = 0.7, p = 0.003). No such association was observed in the healthy subjects (p = 0.6). In the asthmatics, women showed a greater reduction in X5 than men with LBPP (p = 0.009). Conclusions: Smaller baseline airway caliber, as assessed by larger R5, was associated with increased sensitivity to fluid shift in the supine position. We conclude that asthmatics with narrower small airways such as obese asthma patients, women with asthma and those with severe asthma may be more sensitive to the effects fluid shift while supine as during sleep.
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Affiliation(s)
- Swati A Bhatawadekar
- Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
| | - Gabriel Keller
- Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada.,Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cristina O Francisco
- Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
| | - Mark D Inman
- Faculty of Medicine (Respirology), McMaster University, Hamilton, ON, Canada
| | - Jeffrey J Fredberg
- Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA, United States
| | - Susan M Tarlo
- Department of Medicine and Dalla Lana School of Public Health, University of Toronto, ON, Canada.,Toronto Western Hospital, University Health Network, Toronto, ON, Canada
| | - Mathew Stanbrook
- Toronto Western Hospital, University Health Network, Toronto, ON, Canada.,Department of Medicine (Respirology), University of Toronto, Toronto, ON, Canada
| | - Owen D Lyons
- Department of Medicine (Respirology), University of Toronto, Toronto, ON, Canada
| | - Azadeh Yadollahi
- Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
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Shokrollahi M, Rudzicz F, Vena D, Bradley TD, Yadollahi A. A novel approach for acoustic estimation of neck fluid volume between men and women. Med Biol Eng Comput 2017; 56:113-123. [PMID: 28676955 DOI: 10.1007/s11517-017-1675-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 06/25/2017] [Indexed: 11/24/2022]
Abstract
Obstructive Sleep apnea can be caused by fluid shift from the legs to the neck that narrows the upper airway (UA) and contributes to changes in tracheal sound. Tracheal sound is generated from the turbulent airflow in the pharynx and respiratory airways and it has recently been used to estimate increases in neck fluid volume (NFV). However, tracheal sound is also highly variable among people, especially across the sexes. In this paper, a novel method is proposed to select tracheal sound features towards estimating NFV in men and women separately. To validate this method, it was applied to the tracheal sound data of 28 healthy individuals. Our proposed feature selection algorithm is based on sparse representations and incorporates NFV to maximize the relevance of selected features. This feature selection eliminates the dependence of the previous methods on calibrating the model for every individual. Two models, regression and Kalman filters, are then used to estimate NFV from selected features. Kalman filter obtains the highest performance, estimating NFV with more than 90% accuracy in both men and women. This algorithm can be used to develop non-invasive acoustic technologies to investigate the effects of fluid on UA anatomy in general applications. These results could be used to develop convenient devices to monitor the neck edema and its contribution to sleep apnea severity in fluid retaining patients such as heart or renal failure.
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Affiliation(s)
- Mehrnaz Shokrollahi
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada.,Department of Computer Science, University of Toronto, Toronto, Canada
| | - Frank Rudzicz
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada.,Department of Computer Science, University of Toronto, Toronto, Canada
| | - Daniel Vena
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Room 12-106, 550 University Ave., Toronto, ON, M5G 2A2, Canada
| | - T Douglas Bradley
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada.,Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada
| | - Azadeh Yadollahi
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada. .,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Room 12-106, 550 University Ave., Toronto, ON, M5G 2A2, Canada.
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Abstract
Sleep-disordered breathing (SDB) occurs in approximately 50% of patients with reduced left ventricular ejection fraction receiving contemporary heart failure (HF) therapies. Obstructive (OSA) and central sleep apneas (CSA) interrupt breathing by different mechanisms but impose qualitatively similar autonomic, chemical, mechanical, and inflammatory burdens on the heart and circulation. Because contemporary evidence-based drug and device HF therapies have little or no mitigating effect on the acute or long-term consequences of such stimuli, there is a sound mechanistic rationale for targeting SDB to reduce cardiovascular event rates and prolong life. However, the promise of observational studies and randomized trials of small size and duration describing a beneficial effect of treating SDB in HF via positive airway pressure was not realized in 2 recent randomized outcome-driven trials: SAVE, which evaluated the cardiovascular effect of treating OSA in a cohort without HF, and SERVE-HF, which reported the results of a strategy of random allocation of minute-ventilation-triggered adaptive servo-ventilation (ASV) for HF patients with CSA. Whether effective treatment of either OSA or CSA improves the HF trajectory by reducing cardiovascular morbidity or mortality has yet to be definitively established. ADVENT-HF, designed to determine the effect of treating both CSA and non-sleepy OSA HF patients with a peak-airflow triggered ASV algorithm, could resolve this present clinical equipoise concerning the treatment of SDB.
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Affiliation(s)
- Nobuhiko Haruki
- Division of Cardiovascular Medicine, Department of Molecular Medicine and Therapeutics, Tottori University Faculty of Medicine.,The University Health Network and Sinai Health System Division of Cardiology, Department of Medicine, University of Toronto
| | - John S Floras
- The University Health Network and Sinai Health System Division of Cardiology, Department of Medicine, University of Toronto
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Wolley MJ, Pimenta E, Calhoun D, Gordon RD, Cowley D, Stowasser M. Treatment of primary aldosteronism is associated with a reduction in the severity of obstructive sleep apnoea. J Hum Hypertens 2017; 31:561-567. [PMID: 28382959 DOI: 10.1038/jhh.2017.28] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/17/2017] [Accepted: 02/22/2017] [Indexed: 01/22/2023]
Abstract
Obstructive sleep apnoea (OSA) is known to commonly co-exist with primary aldosteronism (PA), but it is unknown if treatment of PA improves sleep apnoea parameters in these patients. We therefore aimed to determine whether specific medical or surgical treatment of PA improves OSA, as measured by the apnoea-hypopnoea index (AHI). We recruited patients undergoing diagnostic workup for PA if they had symptoms suggestive of OSA. Patients with confirmed PA underwent polysomnography (PSG) at baseline and again at least 3 months after specific treatment for PA. Of 34 patients with PA, 7 (21%) had no evidence of OSA (AHI <5), 9 (26%) had mild (AHI ⩾5 and <15), 8 (24%) moderate (AHI ⩾15 and <30) and 10 (29%) severe OSA (AHI ⩾30). Body mass index tertile, neck circumference and 24 h urinary sodium correlated with the AHI. Twenty patients had repeat PSG performed after treatment for PA (mineralocorticoid receptor antagonists in 13 with bilateral PA and adrenalectomy in 7 with unilateral PA). In this group the median (s.d.) AHI reduced from 22.5 (14.7) to 12.3 (12.1) (P=0.02). Neck circumference reduced with PA treatment (41.6 vs 41.2 cm, P=0.012). OSA is common in patients with primary aldosteronism and may improve with specific therapy for this disease. Aldosterone and sodium-mediated fluid retention in the upper airways and neck region may be a potential mechanism for this relationship.
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Affiliation(s)
- M J Wolley
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - E Pimenta
- Experimental Medicine CV/Hem, Clinical Sciences, Global Drug Discovery, Bayer Pharma AG, Wuppertal, Germany
| | - D Calhoun
- Sleep/Wake Disorders Center, Division of Pulmonary, Allergy and Critical Care Medicine and Vascular Biology and Hypertension Program, University of Alabama at Birmingham, Birmingham, AL, USA
| | - R D Gordon
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - D Cowley
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - M Stowasser
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
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60
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Singh B, Yadollahi A, Lyons O, Alshaer H, Bradley TD. The effect of sitting and calf activity on leg fluid and snoring. Respir Physiol Neurobiol 2017; 240:1-7. [PMID: 28214605 DOI: 10.1016/j.resp.2017.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/24/2017] [Accepted: 02/13/2017] [Indexed: 11/28/2022]
Abstract
Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm - no calf exercise while sitting; intervention arm - calf contraction against a pedal resistance while sitting. The effects of sitting±calf activity on LFV and snoring were compared. We found that LFV increased by 216±101.0ml (p<0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8ml (p<0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357±132.9 to 116.2±72.1s/h, p=0.02) suggesting reduced overnight rostral fluid shift to the neck.
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Affiliation(s)
- Bhajan Singh
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, 550 University Avenue, Toronto, ON M5G 2A2, Canada; Department of Pulmonary Physiology & Sleep Medicine, Sir Charles Gairdner Hospital, Hospital Avenue, Nedlands, WA 6009, Australia; Faculty of Science, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; West Australian Sleep Disorders Research Institute, QEII Medical Centre, Hospital Avenue, Nedlands, WA 6009, Australia.
| | - Azadeh Yadollahi
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, 550 University Avenue, Toronto, ON M5G 2A2, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St, Toronto, ON M5S 3G9, Canada.
| | - Owen Lyons
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, 550 University Avenue, Toronto, ON M5G 2A2, Canada.
| | - Hisham Alshaer
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, 550 University Avenue, Toronto, ON M5G 2A2, Canada.
| | - T Douglas Bradley
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, 550 University Avenue, Toronto, ON M5G 2A2, Canada; Centre for Sleep Medicine and Circadian Biology, University of Toronto, 27 King's College Cir, Toronto, ON M5S, Canada; Department of Medicine, University Health Network, Toronto General Hospital, 585 University Ave, Toronto, ON M5G 2N2, Canada.
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Aziz F, Chaudhary K. The Triad of Sleep Apnea, Hypertension, and Chronic Kidney Disease: A Spectrum of Common Pathology. Cardiorenal Med 2016; 7:74-82. [PMID: 27994605 DOI: 10.1159/000450796] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/05/2016] [Indexed: 01/07/2023] Open
Abstract
Obstructive sleep apnea (OSA), hypertension, and chronic kidney disease (CKD) are different entities and are generally managed individually most of the time. However, CKD, OSA, and hypertension share many common risk factors and it is not uncommon to see this complex triad together. In fact, they share similar pathophysiology and have been interlinked with each other. The common pathophysiology includes chronic volume overload, hyperaldosteronism, increased sympathetic activity, endothelial dysfunction, and increased inflammatory markers. The combination of this triad has significant negative impact on the cardiovascular health, and increases the mortality and morbidity in this complicated group of patients. On one hand, progression of CKD can lead to the worsening of OSA and hypertension; similarly, worsening sleep apnea can make the hypertension difficult to treat and enhance the progression of CKD. This review article highlights the bidirectional interlink among these apparently different disease processes which share common pathophysiological mechanisms and emphasizes the importance of treating them collectively to improve outcomes.
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Affiliation(s)
- Fahad Aziz
- Division of Nephrology, University of Missouri Health Science Center, Columbia, MO, USA
| | - Kunal Chaudhary
- Division of Nephrology, University of Missouri Health Science Center, Columbia, MO, USA; Nephrology Section, Harry S. Truman Veterans' Hospital, Columbia, MO, USA
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Yadollahi A, Vena D, Lyons OD, Bradley TD. Relationship of Fluid Accumulation in the Neck to Sleep Structure in Men during Daytime Sleep. J Clin Sleep Med 2016; 12:1365-1371. [PMID: 27397662 DOI: 10.5664/jcsm.6190] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 05/31/2016] [Indexed: 12/22/2022]
Abstract
STUDY OBJECTIVES Induction of fluid overload during sleep in older men causes fluid accumulation in the neck, worsens obstructive sleep apnea (OSA), and reduces sleep efficiency and slow wave sleep. However, it is not clear whether disrupted sleep structure was related to age, fluid accumulation, or to OSA severity as assessed by the apnea-hypopnea index (AHI). We hypothesize that fluid accumulation in the neck is a significant contributor to the sleep structure. METHODS Twenty non-obese men, 46 ± 11 years, underwent a daytime sleep study following a night of sleep deprivation. Before and after sleep, neck circumference (NC), upper airway cross-sectional area, and neck fluid volume (NFV) were assessed. Stepwise regression analyses were used to determine factors that contributed to sleep structure, AHI, and arousal frequency. Independent factors were age, NC, ΔNC, ΔNFV, and AHI (excluded for AHI and arousal). RESULTS Subjects slept for 145 ± 44 minutes with a mean AHI of 26 ± 25. After sleep, NC and NFV increased and the upper airway narrowed (all: p < 0.001). ΔNC and ΔNFV correlated directly with %N2 and inversely with %N3 sleep. Regression analyses revealed that only ΔNC correlated directly with %N2 sleep (r2 = 0.44, p = 0.001). ΔNC, ΔNFV, and pre-sleep NC correlated inversely with %N3 sleep (r2 = 0.76, p < 0.001). Pre-sleep NC and ΔNC correlated directly with AHI and arousal frequency. CONCLUSIONS Fluid accumulation in the neck and larger neck circumference are related to impaired sleep structure with reduced %N3 sleep. Fluid accumulation in the neck had stronger contribution to sleep structure than AHI or age.
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Affiliation(s)
- Azadeh Yadollahi
- Toronto Rehabilitation Institute-University Health Network, Toronto, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Daniel Vena
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Owen D Lyons
- Toronto Rehabilitation Institute-University Health Network, Toronto, Canada.,Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada.,Department of Medicine, University Health Network, Toronto General Hospital, Toronto, Canada
| | - T Douglas Bradley
- Toronto Rehabilitation Institute-University Health Network, Toronto, Canada.,Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada.,Department of Medicine, University Health Network, Toronto General Hospital, Toronto, Canada
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63
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Khurshid K, Yabes J, Weiss PM, Dharia S, Brown L, Unruh M, Jhamb M. Effect of Antihypertensive Medications on the Severity of Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis. J Clin Sleep Med 2016; 12:1143-51. [PMID: 27397663 PMCID: PMC4957192 DOI: 10.5664/jcsm.6054] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 04/01/2016] [Indexed: 11/13/2022]
Abstract
STUDY OBJECTIVES Obstructive sleep apnea (OSA) is an independent risk factor for hypertension (HTN). Increasing evidence from animal and human studies suggests that HTN exacerbates OSA. We performed a systematic review and meta-analysis of studies evaluating the effect of anti-hypertensive medications on the severity of OSA. METHODS A literature search of PubMed and Embase was done using search concepts of OSA, HTN, and drug classes used to treat HTN. Studies that reported changes in the severity of OSA objectively by using apnea-hypopnea index (AHI) or respiratory disturbance index (RDI) were included. Pooled mean difference estimates were calculated. Tests for heterogeneity, publication bias, and subgroup sensitivity analysis were conducted. RESULTS Of 27,376 studies screened, only 11 met inclusion criteria, including 5 randomized controlled trials and 6 single-arm prospective trials. The pooled mean difference estimate (95% confidence interval [CI]), based on a random-effects model, was -5.69 (95% CI -10.74 to -0.65), consistent with an overall decrease in AHI or RDI attributable to antihypertensive medications. The effect size was even more pronounced, -14.52 (95% CI -25.65 to -3.39), when only studies using diuretics were analyzed. There was no significant heterogeneity or publication bias among the studies. Meta-regression indicated neither age, baseline AHI, nor change in systolic/diastolic blood pressure influenced the results. CONCLUSIONS Collectively, findings from these relatively small, short-term studies tend to support the contention that treatment with antihypertensive agents confers a statistically significant, albeit small, reduction in the severity of OSA, which may be more pronounced with the use of diuretics.
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Affiliation(s)
- Kiran Khurshid
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Jonathan Yabes
- Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Patricia M. Weiss
- Health Sciences Library System, University of Pittsburgh, Pittsburgh, PA
| | - Sushma Dharia
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of New Mexico, Albuquerque, NM
| | - Lee Brown
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of New Mexico, Albuquerque, NM
| | - Mark Unruh
- Nephrology Division, Department of Internal Medicine, University of New Mexico, Albuquerque, NM
| | - Manisha Jhamb
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA
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Gavrilovic B, Bradley TD, Vena D, Lyons OD, Gabriel JM, Popovic MR, Yadollahi A. Factors predisposing to worsening of sleep apnea in response to fluid overload in men. Sleep Med 2016; 23:65-72. [PMID: 27692279 DOI: 10.1016/j.sleep.2016.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/03/2016] [Accepted: 05/22/2016] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Obstructive sleep apnea (OSA) is highly prevalent in patients with fluid-retaining conditions. Using bioimpedance measurements, previous studies have shown that the greater the amount of fluid redistributed from the legs to the neck overnight, the greater the severity of OSA. Our objective was to investigate factors that predispose the development or worsening of OSA in response to experimental fluid overload. METHODS Fifteen normotensive and non-obese adult men with and without OSA underwent polysomnography (PSG) during which normal saline was infused intravenously at a minimal rate to keep the vein open (control) or as a bolus of 22 ml/kg body weight (approximately 2 L) in a random order and crossed over after a week. RESULTS AND CONCLUSIONS Before and after sleep, neck circumference and bioimpedance were measured to calculate neck resistance, reactance, phase angle, and fluid volume. Subjects who experienced more than a twofold increase in apnea-hypopnea index (AHI) or obstructive AHI from control to intervention and had an AHI>10 during intervention were considered susceptible to the development or worsening of OSA. Baseline neck circumference and phase angle before saline infusion were independently associated with increased susceptibility to developing or worsening OSA in response to saline infusion. In non-obese men, a larger neck circumference and bioimpedance phase angle of the neck, which may be associated with larger pharyngeal tissue content, is associated with increased susceptibility for worsening of OSA in response to fluid overloading.
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Affiliation(s)
- Bojan Gavrilovic
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - T Douglas Bradley
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada; Department of Medicine, University of Toronto, Toronto, Canada
| | - Daniel Vena
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Owen D Lyons
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada
| | - Joseph M Gabriel
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada
| | - Milos R Popovic
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Azadeh Yadollahi
- Toronto Rehabilitation Institute, University Health Network, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada.
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Abstract
In end-stage renal disease (ESRD) and heart failure, conditions characterized by fluid overload, both obstructive sleep apnea (OSA) and central sleep apnea (CSA) are highly prevalent. This observation suggests that fluid overload may be a unifying mechanism in the pathogenesis of both OSA and CSA in these conditions. An overnight rostral fluid shift from the legs to the neck and lungs has been shown to contribute to the pathogenesis of OSA and CSA, respectively, in various different patient populations. This article reviews the evidence that supports a role for fluid overload and overnight fluid shift in the pathogenesis of sleep apnea in ESRD. The diagnosis, epidemiology, and clinical features of sleep apnea in patients with ESRD also are considered.
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Affiliation(s)
- Owen D Lyons
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada; Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Ontario, Canada.
| | - T Douglas Bradley
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada; Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Ontario, Canada; Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Christopher T Chan
- Division of Nephrology, Department of Medicine, University Health Network, Toronto General Hospital, Toronto, Ontario, Canada
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Lam T, Singh M, Yadollahi A, Chung F. Is Perioperative Fluid and Salt Balance a Contributing Factor in Postoperative Worsening of Obstructive Sleep Apnea? Anesth Analg 2016; 122:1335-9. [DOI: 10.1213/ane.0000000000001169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Mendelson M, Lyons OD, Yadollahi A, Inami T, Oh P, Bradley TD. Effects of exercise training on sleep apnoea in patients with coronary artery disease: a randomised trial. Eur Respir J 2016; 48:142-50. [PMID: 27076578 DOI: 10.1183/13993003.01897-2015] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Accepted: 02/12/2016] [Indexed: 01/10/2023]
Abstract
Overnight fluid shift from the legs to the neck and lungs may contribute to the pathogenesis of obstructive sleep apnoea (OSA) and central sleep apnoea (CSA). We hypothesised that exercise training will decrease the severity of OSA and CSA in patients with coronary artery disease (CAD) by decreasing daytime leg fluid accumulation and overnight rostral fluid shift.Patients with CAD and OSA or CSA (apnoea-hypopnoea index >15 events per h) were randomised to 4 weeks of aerobic exercise training or to a control group. Polysomnography, with measurement of leg, thoracic and neck fluid volumes and upper-airway cross-sectional area (UA-XSA) before and after sleep, was performed at baseline and follow-up.17 patients per group completed the study. Apnoea-hypopnoea index decreased significantly more in the exercise group than in the control group (31.1±12.9 to 20.5±9.4 versus 28.1±13.5 to 27.0±15.1 events per h, p=0.047), in association with a greater reduction in the overnight change in leg fluid volume (579±222 to 466±163 versus 453±164 to 434±141 mL, p=0.04) and by a significantly greater increase in the overnight change in UA-XSA in the exercise group (p=0.04).In patients with CAD and sleep apnoea, exercise training decreases sleep apnoea severity via attenuation of overnight fluid shift and an increase in UA-XSA.
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Affiliation(s)
- Monique Mendelson
- Sleep Research Laboratory, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, ON, Canada
| | - Owen D Lyons
- Sleep Research Laboratory, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, ON, Canada Dept of Medicine, University Health Network, Toronto General Hospital, Toronto, ON, Canada
| | - Azadeh Yadollahi
- Sleep Research Laboratory, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, ON, Canada Institute of Biomaterial and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Toru Inami
- Sleep Research Laboratory, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, ON, Canada Dept of Medicine, University Health Network, Toronto General Hospital, Toronto, ON, Canada
| | - Paul Oh
- Cardiac Rehabilitation and Prevention, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada
| | - T Douglas Bradley
- Sleep Research Laboratory, University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, ON, Canada Dept of Medicine, University Health Network, Toronto General Hospital, Toronto, ON, Canada
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69
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Bursztyn M. Left Ventricular Hypertrophy in Hypertension and Nocturnal Blood Pressure. J Clin Hypertens (Greenwich) 2015; 17:914-5. [PMID: 26176341 PMCID: PMC8031968 DOI: 10.1111/jch.12602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Michael Bursztyn
- Hypertension UnitDepartment of MedicineHadassah‐Hebrew University Medical CenterJerusalemIsrael
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70
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Furlan SF, Braz CV, Lorenzi-Filho G, Drager LF. Management of Hypertension in Obstructive Sleep Apnea. Curr Cardiol Rep 2015; 17:108. [DOI: 10.1007/s11886-015-0663-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
More is known about the epidemiology of drug-resistant hypertension than particular pathogenic factors and pathways. Several recurring themes, however, seem evident on using insight from epidemiology and general knowledge of the pathophysiology of hypertension. Specifically, 4 main pathways converge on drug resistance including sodium handling, sympathetic nervous system activation, endothelial dysfunction, and arterial stiffness. These factors, and the various pathways and elements contributing to them, are reviewed. In addition to describing how these factors exert their individual influences on resistant hypertension, several examples of how interactions between these factors, particularly in the case of chronic kidney disease, are included. At the conclusion of this review some thoughts are offered on additional mechanisms and areas for potential research.
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Redolfi S, Bettinzoli M, Venturoli N, Ravanelli M, Pedroni L, Taranto-Montemurro L, Arnulf I, Similowski T, Tantucci C. Attenuation of obstructive sleep apnea and overnight rostral fluid shift by physical activity. Am J Respir Crit Care Med 2015; 191:856-8. [PMID: 25830523 DOI: 10.1164/rccm.201412-2192le] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Lam TD, Singh M, Chung F. Salt Content in IV Fluids Given Intraoperatively May Influence Postoperative OSA Severity. Sleep 2015; 38:989. [PMID: 25581924 DOI: 10.5665/sleep.4756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 10/24/2014] [Indexed: 11/03/2022] Open
Affiliation(s)
- Thach D Lam
- Department of Anesthesiology, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Mandeep Singh
- Department of Anesthesiology, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Frances Chung
- Department of Anesthesiology, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
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Roumelioti ME, Brown LK, Unruh ML. The Relationship Between Volume Overload in End-Stage Renal Disease and Obstructive Sleep Apnea. Semin Dial 2015; 28:508-13. [PMID: 25940851 DOI: 10.1111/sdi.12389] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Obstructive sleep apnea (OSA) is common, underdiagnosed, and undertreated among patients with end-stage renal disease (ESRD). As in all cases, pathogenesis of OSA is related to repeated upper airway (UA) occlusion or narrowing, but in ESRD, additional contributory factors likely include uremic destabilization of central respiratory control and anatomic changes in the UA related to fluid status. Pulmonary congestion is common in acute and chronic kidney failure and is a consequence of cardiomyopathy and fluid overload, two potentially reversible risk factors. Emerging evidence suggests that volume overload also reduces the UA caliber. The diminution in UA area as well as destabilization of ventilatory control in ESRD have been postulated as causes of increased OSA prevalence and severity in these patients, and creates a vicious cycle wherein OSA exacerbates fluid overload disorders such as in congestive heart failure (CHF) and ESRD, which then further worsen OSA. Dialysis modalities may differ in their effects on volume status, the accumulation of uremic toxins, and acid-base status, and as a consequence, on the emergence and severity of OSA. Given the contribution of excess fluid to both the severity of nocturnal hypoxia and UA narrowing, establishing and maintaining dry weight is of particular importance when managing OSA in ESRD. Clinical trials to determine the extent to which more aggressive fluid removal in ESRD patients may alleviate OSA are needed.
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Affiliation(s)
- Maria-Eleni Roumelioti
- Division of Nephrology, Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, New Mexico
| | - Lee K Brown
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of New Mexico School of Medicine, and the Program in Sleep Medicine, University of New Mexico Health Sciences Centre, Albuquerque, New Mexico
| | - Mark L Unruh
- Division of Nephrology, Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, New Mexico
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Fiori CZ, Martinez D, Gonçalves SC, Montanari CC, Fuchs FD. Effect of diuretics and sodium-restricted diet on sleep apnea severity: study protocol for a randomized controlled trial. Trials 2015; 16:188. [PMID: 25906818 PMCID: PMC4411798 DOI: 10.1186/s13063-015-0699-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 01/06/2015] [Indexed: 01/01/2023] Open
Abstract
Background Obstructive sleep apnea occurs as a result of increased collapsibility of the upper airway. Overnight fluid displacement from the legs to the neck causes pharyngeal narrowing and increased apnea severity. Sodium intake is associated with apnea severity. We hypothesized that interventions that decrease bodily fluid content might reduce the severity of sleep apnea. Methods/design This is a randomized clinical trial including men with an apnea-hypopnea index greater than 30 events/hour, previously diagnosed by full-night in-laboratory polysomnography. A total of 54 men will be included and randomly assigned to three groups: Diuretic (n = 18), sodium-restricted diet (n = 18), and control (n = 18). The intervention will last one week. Intention-to-treat and per-protocol analyses will be performed. The diuretic group will receive combined spironolactone 100 mg plus furosemide 20 mg daily, taken in the morning. The diet group will receive a regimen with a maximum intake of 3 g of sodium per day. The control group will receive a placebo pill and will maintain all eating habits while keeping a recall diary of their dietary behavior. The primary outcome measure will be change in apnea-hypopnea index. The secondary outcome measures will be variations of: anthropometric and bioelectrical impedance variables, office blood pressure, respiratory variables from in-home level III polysomnography, excessive daytime sleepiness, glycolipid profile, C-reactive protein, 24 h urinary variables, and adverse events. Discussion Despite the high efficacy of continuous positive airway pressure to reverse upper airway obstruction in sleep apnea, partial adherence to this form of treatment reduces its efficiency. Thus, additional forms of treating apnea need to be investigated. If the results of this proof-of-concept trial show that decreases in bodily fluid content, either by diuretic or dietary intervention, reduces the severity of sleep apnea, further investigation will be necessary before these results can be translated and adopted as an adjunct apnea therapy. Trial registration clinicaltrials.gov NCT01945801.
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Affiliation(s)
- Cintia Zappe Fiori
- Graduate Studies Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Denis Martinez
- Graduate Studies Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Graduate Studies Program in Medical Sciences, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Cardiology Unit, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil.
| | - Sandro Cadaval Gonçalves
- Graduate Studies Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Cardiology Unit, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil.
| | - Carolina Caruccio Montanari
- Graduate Studies Program in Medical Sciences, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Flavio Danni Fuchs
- Graduate Studies Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Cardiology Unit, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil.
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Heart Failure and Sleep Apnea. Can J Cardiol 2015; 31:898-908. [PMID: 26112300 DOI: 10.1016/j.cjca.2015.04.017] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/23/2015] [Accepted: 04/12/2015] [Indexed: 12/18/2022] Open
Abstract
Obstructive and central sleep apnea are far more common in heart failure patients than in the general population and their presence might contribute to the progression of heart failure by exposing the heart to intermittent hypoxia, increased preload and afterload, sympathetic nervous system activation, and vascular endothelial dysfunction. There is now substantial evidence that supports a role for fluid overload and nocturnal rostral fluid shift from the legs as unifying mechanisms in the pathogenesis of obstructive and central sleep apnea in heart failure patients, such that the predominant type of sleep apnea is related to the relative distribution of fluid from the leg to the neck and chest. Despite advances in therapies for heart failure, mortality rates remain high. Accordingly, the identification and treatment of sleep apnea in patients with heart failure might offer a novel therapeutic target to modulate this increased risk. In heart failure patients with obstructive or central sleep apnea, continuous positive airway pressure has been shown to improve cardiovascular function in short-term trials but this has not translated to improved mortality or reduced hospital admissions in long-term randomized trials. Other forms of positive airway pressure such as adaptive servoventilation have shown promising results in terms of attenuation of sleep apnea and improvement in cardiovascular function in short-term trials. Large scale, randomized trials are required to determine whether treating sleep apnea with various interventions can reduce morbidity and mortality.
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Use of continuous positive airway pressure for sleep apnea in the treatment of hypertension. Curr Opin Nephrol Hypertens 2015; 23:462-7. [PMID: 24992567 DOI: 10.1097/mnh.0000000000000047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
PURPOSE OF REVIEW Obstructive sleep apnea (OSA) and hypertension are highly prevalent and treatable conditions that often coexist and both contribute to an increased cardiovascular risk. The ability of continuous positive airway pressure (CPAP) to improve blood pressure in hypertensive patients with OSA is debated. This review highlights findings from recent studies that have investigated the impact of CPAP on blood pressure in patients with OSA. RECENT FINDINGS Comparing the results of various studies is complicated by important methodological differences among them. In hypertensive patients with OSA, treatment with CPAP improves blood pressure to a smaller degree than that derived from antihypertensive medication. Patients with more severe OSA and with greater adherence to CPAP are likely to gain the most benefit from the therapy. SUMMARY CPAP should be used in combination with antihypertensive medications in hypertensive patients with OSA. CPAP has the additional benefits of restoring nocturnal dipping and improving arterial stiffness, thus potentially influencing cardiovascular morbidity in these high-risk patients.
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78
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Ding N, Lin W, Zhang XL, Ding WX, Gu B, Ni BQ, Zhang W, Zhang SJ, Wang H. Overnight fluid shifts in subjects with and without obstructive sleep apnea. J Thorac Dis 2015; 6:1736-41. [PMID: 25589967 DOI: 10.3978/j.issn.2072-1439.2014.11.19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 10/15/2014] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To investigate the characteristics of baseline body fluid content and overnight fluid shifts between non-obstructive sleep apnea (non-OSA) and obstructive sleep apnea (OSA) subjects. METHODS A case-controlled study was performed between February 2013 and January 2014, with 36 (18 OSA and 18 non-OSA) outpatients enrolled in this study. Polysomnographic parameters and results of body fluid were compared between the two groups. RESULTS There were no differences in age, weight, and body mass index (BMI) between groups. Compared with the non-OSA group, OSA group had significantly higher neck circumference (NC) and fluid volume shift in the legs. OSA patients had higher left and right leg fluid indices than non-OSA subjects. There were significant correlations between apnoea-hypopnoea index and baseline fluid indices in both legs as well as the reduction in overnight change in both legs fluid volume. The increase in NC was also significantly correlated with the reduction in overnight change in both legs fluid volume, but not with the change in head and neck fluid volume. There were significant correlations between change in NC and increased fluid shifts in head and neck volume. CONCLUSIONS OSA patients had a higher baseline fluid content in both legs as compared with non-OSA subjects, which may be the basic factor with regards to fluid shifts in OSA patients. The increase in head and neck fluid shift volume did not directly correlate with the severity of OSA.
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Affiliation(s)
- Ning Ding
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Wei Lin
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Xi-Long Zhang
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Wen-Xiao Ding
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Bing Gu
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Bu-Qing Ni
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Wei Zhang
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Shi-Jiang Zhang
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Hong Wang
- 1 Department of Respiratory Medicine, 2 Department of Geriatric Medicine, 3 Department of Laboratory Medicine, 4 Department of Cardiothoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
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White LH, Lyons OD, Yadollahi A, Ryan CM, Bradley TD. Night-to-night variability in obstructive sleep apnea severity: relationship to overnight rostral fluid shift. J Clin Sleep Med 2015; 11:149-56. [PMID: 25406274 PMCID: PMC4298772 DOI: 10.5664/jcsm.4462] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/14/2014] [Indexed: 01/03/2023]
Abstract
STUDY OBJECTIVES Overnight rostral fluid shift from the legs to the neck may narrow the pharynx and contribute to obstructive sleep apnea (OSA) pathogenesis. We hypothesized that night-to-night changes in the apnea-hypopnea index (AHI) would be associated with changes in overnight rostral fluid shift. METHODS Twenty-six patients with OSA (AHI ≥10) underwent two polysomnograms 14 days apart with measurement of neck and leg fluid volumes (LFV), neck circumference and upper-airway cross-sectional area before and after sleep. RESULTS Although mean AHI did not differ between polysomnograms, 35% of patients had a difference in AHI >10, indicating significant intra-individual variability. There were direct correlations between change in non-rapid-eye movement (NREM), but not REM AHI and change in evening LFV between polysomnograms (r = 0.440, p = 0.036 and r = 0.005, p = 0.982, respectively) and between change in supine, but not non-supine AHI and change in evening LFV (r = 0.483, p = 0.020 and r = 0.269, p = 0.280, respectively). An increase in evening LFV between polysomnograms was associated with a greater overnight decrease in LFV (r = 0.560, p = 0.005) and a greater overnight increase in neck fluid volume (r = 0.498, p = 0.016). Additionally, a greater overnight increase in neck circumference was associated with a greater overnight increase in neck fluid volume between polysomnograms (r = 0.453, p = 0.020) and a greater overnight decrease in upper-airway cross-sectional area (r = -0.587, p = 0.005). CONCLUSION Intra-individual variability in OSA severity may be partly explained by day-to-day changes in evening leg fluid volume and overnight rostral fluid shift, which may be most important in the pathogenesis of OSA during NREM and supine sleep.
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Affiliation(s)
- Laura H. White
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada
- Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, Ontario, Canada
| | - Owen D. Lyons
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada
- Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, Ontario, Canada
| | - Azadeh Yadollahi
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada
- Institute of Biomaterial and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Clodagh M. Ryan
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada
- Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, Ontario, Canada
- Department of Medicine of the University Health Network Toronto General Hospital, Toronto, Ontario, Canada
| | - T. Douglas Bradley
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, Ontario, Canada
- Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, Ontario, Canada
- Department of Medicine of the University Health Network Toronto General Hospital, Toronto, Ontario, Canada
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Saha S, Taheri M, Mossuavi Z, Yadollahi A. Effects of changing in the neck circumference during sleep on snoring sound characteristics. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2015:2235-2238. [PMID: 26736736 DOI: 10.1109/embc.2015.7318836] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Rostral fluid shift during sleep from the lower body part into the neck can increase neck circumference (NC) and narrow the upper airway. Such narrowing in the upper airway may increase turbulence of airflow passing through the upper airway; thus, induce snoring. The objective of this study was to investigate the effects of changes in NC during sleep on snoring sound characteristics. Fifteen non-obese men slept supine, and their sleep was monitored by a regular polysomnography. Snoring sounds were recorded with a microphone attached to the neck. NC was measured before and after sleep with a measuring tape. Snoring sounds' average power was calculated in different frequency ranges of 100 - 4000 Hz, 100 - 150 Hz, 150 - 450 Hz, 450 - 600 Hz, 600 - 1200 Hz, 1200 - 1800 Hz, 1800 - 2500 Hz and 2500 - 4000 Hz. Statistical analysis showed that increases in NC after sleep were strongly correlated with higher average power of the snoring sounds in the frequency ranges of 100-4000 Hz (r=0.74, P=0.004), 100-150 Hz (r=0.70, P=0.008), 150-450 Hz (r=0.73, P=0.005), and 450 - 600 Hz (r= 0.65, P=0.025). These results encourage the use of snoring sound analysis for monitoring the effects of fluid accumulation in the neck in relation to sleep apnea.
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White LH, Lyons OD, Yadollahi A, Ryan CM, Bradley TD. Effect of below-the-knee compression stockings on severity of obstructive sleep apnea. Sleep Med 2014; 16:258-64. [PMID: 25620198 DOI: 10.1016/j.sleep.2014.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 11/05/2014] [Accepted: 12/07/2014] [Indexed: 01/10/2023]
Abstract
BACKGROUND Overnight fluid shift from the legs to the neck may narrow the upper airway and contribute to obstructive sleep apnea (OSA) pathogenesis. We hypothesized that below-the-knee compression stockings will decrease OSA severity in a general OSA population by decreasing daytime leg fluid accumulation and overnight fluid shift and increasing upper-airway size. METHODS Patients with OSA (apnea-hypopnea index ≥ 10) were randomized to wear compression stockings during the daytime or to a control group for 2 weeks. Overnight polysomnography with measurement of leg and neck fluid volumes and upper-airway cross-sectional area before and after sleep was performed at baseline and follow-up. The primary outcome was change in the apnea-hypopnea index. RESULTS Twenty-two patients randomized to compression stockings and 23 to control completed the study. The apnea-hypopnea index decreased significantly more in the compression stockings than in the control group (from 32.4 ± 20.0 to 23.8 ± 15.5 vs. from 31.2 ± 25.0 to 30.3 ± 23.8, p = 0.042), in association with a significantly greater reduction in the overnight decrease in leg fluid volume (p = 0.028), and a significantly greater increase in morning upper-airway cross-sectional area (p = 0.006). Overnight change in neck fluid volume was unchanged. CONCLUSION These observations suggest that in, a general OSA population, below-the-knee compression stockings decrease OSA severity modestly via attenuation of overnight fluid shift and consequent upper-airway dilatation.
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Affiliation(s)
- Laura H White
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada; Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, ON, Canada
| | - Owen D Lyons
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada; Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, ON, Canada
| | - Azadeh Yadollahi
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada; Institute of Biomaterial and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Clodagh M Ryan
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada; Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, ON, Canada; Department of Medicine of the University Health Network Toronto General Hospital, Toronto, ON, Canada
| | - T Douglas Bradley
- Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute, Toronto, ON, Canada; Centre for Sleep Medicine and Circadian Biology of the University of Toronto, Toronto, ON, Canada; Department of Medicine of the University Health Network Toronto General Hospital, Toronto, ON, Canada.
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Liangos O. Resistant hypertension and renal denervation: what do the guidelines say? A nephrologist's perspective. Interv Cardiol 2014. [DOI: 10.2217/ica.14.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Sutherland K, Cistulli PA. Recent advances in obstructive sleep apnea pathophysiology and treatment. Sleep Biol Rhythms 2014. [DOI: 10.1111/sbr.12098] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Kate Sutherland
- Department of Respiratory and Sleep Medicine; Center for Sleep Health and Research; Royal North Shore Hospital; University of Sydney; Sydney New South Wales Australia
- Discipline of Sleep Medicine; Sydney Medical School; University of Sydney; Sydney New South Wales Australia
- Woolcock Institute of Medical Research; University of Sydney; Sydney New South Wales Australia
| | - Peter A Cistulli
- Department of Respiratory and Sleep Medicine; Center for Sleep Health and Research; Royal North Shore Hospital; University of Sydney; Sydney New South Wales Australia
- Discipline of Sleep Medicine; Sydney Medical School; University of Sydney; Sydney New South Wales Australia
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84
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Jhamb M, Unruh M. Bidirectional relationship of hypertension with obstructive sleep apnea. Curr Opin Pulm Med 2014; 20:558-64. [DOI: 10.1097/mcp.0000000000000102] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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White LH, Bradley TD, Logan AG. Pathogenesis of obstructive sleep apnoea in hypertensive patients: role of fluid retention and nocturnal rostral fluid shift. J Hum Hypertens 2014; 29:342-50. [DOI: 10.1038/jhh.2014.94] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/23/2014] [Accepted: 09/03/2014] [Indexed: 11/09/2022]
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86
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Effects of continuous positive airway pressure on blood pressure in hypertensive patients with obstructive sleep apnoea. J Hypertens 2014; 32:2279-80. [PMID: 25271918 DOI: 10.1097/hjh.0000000000000377] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yadollahi A, Gabriel JM, White LH, Taranto Montemurro L, Kasai T, Bradley TD. A randomized, double crossover study to investigate the influence of saline infusion on sleep apnea severity in men. Sleep 2014; 37:1699-705. [PMID: 25197812 DOI: 10.5665/sleep.4084] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 03/06/2014] [Indexed: 12/24/2022] Open
Abstract
STUDY OBJECTIVES Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). DESIGN Randomized, single-blind, double crossover study. SETTING Research sleep laboratory. PATIENTS OR PARTICIPANTS Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. INTERVENTIONS During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. MEASUREMENTS AND RESULTS Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). CONCLUSIONS Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies.
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Affiliation(s)
- Azadeh Yadollahi
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Joseph M Gabriel
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Laura H White
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada and Department of Medicine, University Health Network, Toronto General Hospital, Toronto, Canada
| | - Luigi Taranto Montemurro
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada
| | - Takatoshi Kasai
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada
| | - T Douglas Bradley
- Sleep Research Laboratory, University Health Network, Toronto Rehabilitation Institute, Toronto, Canada and Centre for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Canada and Department of Medicine, University Health Network, Toronto General Hospital, Toronto, Canada
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Genta-Pereira DC, Pedrosa RP, Lorenzi-Filho G, Drager LF. Sleep Disturbances and Resistant Hypertension: Association or Causality? Curr Hypertens Rep 2014; 16:459. [DOI: 10.1007/s11906-014-0459-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Is intensified diuretic therapy an effective new treatment strategy in obstructive sleep apnoea patients with uncontrolled hypertension? J Hypertens 2014; 32:484-6. [DOI: 10.1097/hjh.0000000000000108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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