Document Detail


Selective potentiation of peripheral chemoreflex sensitivity in obstructive sleep apnea.
MedLine Citation:
PMID:  10069786     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: The chemoreflexes are an important mechanism for regulation of both breathing and autonomic cardiovascular function. Abnormalities in chemoreflex mechanisms may be implicated in increased cardiovascular stress in patients with obstructive sleep apnea (OSA). We tested the hypothesis that chemoreflex function is altered in patients with OSA. METHODS AND RESULTS: We compared ventilatory, sympathetic, heart rate, and blood pressure responses to hypoxia, hypercapnia, and the cold pressor test in 16 untreated normotensive patients with OSA and 12 normal control subjects matched for age and body mass index. Baseline muscle sympathetic nerve activity (MSNA) was higher in the patients with OSA than in the control subjects (43+/-4 versus 21+/-3 bursts per minute; P<0. 001). During hypoxia, patients with OSA had greater increases in minute ventilation (5.8+/-0.8 versus 3.2+/-0.7 L/min; P=0.02), heart rate (10+/-1 versus 7+/-1 bpm; P=0.03), and mean arterial pressure (7+/-2 versus 0+/-2 mm Hg; P=0.001) than control subjects. Despite higher ventilation and blood pressure (both of which inhibit sympathetic activity) in OSA patients, the MSNA increase during hypoxia was similar in OSA patients and control subjects. When the sympathetic-inhibitory influence of breathing was eliminated by apnea during hypoxia, the increase in MSNA in OSA patients (106+/-20%) was greater than in control subjects (52+/-23%; P=0.04). Prolongation of R-R interval with apnea during hypoxia was also greater in OSA patients (24+/-6%) than in control subjects (7+/-5%) (P=0.04). Autonomic, ventilatory, and blood pressure responses to hypercapnia and the cold pressor test in OSA patients were not different from those observed in control subjects. CONCLUSIONS: OSA is associated with a selective potentiation of autonomic, hemodynamic, and ventilatory responses to peripheral chemoreceptor activation by hypoxia.
Authors:
K Narkiewicz; P J van de Borne; C A Pesek; M E Dyken; N Montano; V K Somers
Related Documents :
8973756 - Role of the autonomic nervous system in the acute blood pressure elevation during repet...
7468246 - Effect of hypoxia on mechanical properties of isolated rat heart. comparison of the eff...
12091176 - Laryngeal muscle activities with cerebral hypoxia-ischemia in newborn lambs.
17893456 - 4-aminopyridine restores impaired hypoxic pulmonary vasoconstriction in endotoxemic mice.
6706746 - Effect of alveolar hypoxia on regional pulmonary perfusion.
3505266 - Effects of infant ventilator design on spontaneous breathing.
Publication Detail:
Type:  Clinical Trial; Controlled Clinical Trial; Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Circulation     Volume:  99     ISSN:  0009-7322     ISO Abbreviation:  Circulation     Publication Date:  1999 Mar 
Date Detail:
Created Date:  1999-04-13     Completed Date:  1999-04-13     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0147763     Medline TA:  Circulation     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1183-9     Citation Subset:  AIM; IM    
Affiliation:
Cardiovascular Division, Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Anoxia / physiopathology
Autonomic Nervous System / physiopathology
Blood Pressure / physiology
Chemoreceptor Cells / physiology*
Cold Temperature
Female
Humans
Hypercapnia / physiopathology
Male
Reflex / physiology*
Respiratory Mechanics / physiology
Rest / physiology
Sleep Apnea Syndromes / physiopathology*
Grant Support
ID/Acronym/Agency:
3F05-TW-05200/TW/FIC NIH HHS; HL-14388/HL/NHLBI NIH HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Randomized, controlled trial of long-term moderate exercise training in chronic heart failure: effec...
Next Document:  Acute saline infusion reduces alveolar-capillary membrane conductance and increases airflow obstruct...