HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Permissions Request Permissions Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Spicuzza, L. Articles by Bernardi, L. Search for Related Content PubMed PubMed Citation Articles by Spicuzza, L. Articles by Bernardi, L.

Sleep-related hypoxaemia and excessive erythrocytosis in Andean high-altitude natives

¹ Dept of Internal Medicine and Medical Specialities, University of Catania, ² Dept of Internal Medicine, and ⁵ Pathology, IRCCS S. Matteo and University of Pavia, Italy. ³ University Cayetano Heredia, Lima, Peru. ⁴ Dept of Anaesthesiology, University of Regensburg, Germany.

CORRESPONDENCE: L. Spicuzza, Dept of Internal Medicine and Medical Specialities, University of Catania, Catania, Italy. Fax: 39 0957594532. E-mail: luciaspicuzza@tiscalinet.it

Keywords: autonomic nervous system, chronic mountain sickness, erythropoietin, high altitude, polycythaemia, sleep disturbances

Received: January 3, 2003
Accepted August 21, 2003

To determine whether nocturnal hypoxaemia contributes to the excessive erythrocytosis (EE) in Andean natives, standard polysomnographies were performed in 10 patients with EE and in 10 controls (mean haematocrit 76.6±1.3% and 54.4±0.8%, respectively) living at an altitude of 4,380 m. In addition, the effect of O₂ administration for 1 h prior to sleep, and the relationship between the hypoxic/hypercapnic ventilatory response and the apnoea/hypopnoea index (AHI) during sleep were studied.

Awake arterial oxygen saturation (S_a,O2) was significantly lower in patients with EEthan in controls (83.7±0.3% versus 85.6±0.4%). In both groups, the mean S_a,O2 significantly decreased during sleep (to 80.0±0.8% in EE and to 82.8±0.5% in controls). The mean S_a,O2 values remained significantly lower in patients with EE than in controls at all times of the night, and patients with EE spent significantly more time than the controls with an S_a,O2 of <80%. There were no differences between the two groups in the number and duration of the apnoeas/hypopnoeas. None of these variables were affected by O₂ administration. In both groups the AHI positively correlated with the hypercapnic ventilatory response.

Andean natives undergo minor respiratory disorders during sleep. The reduction inoxygen saturation found in subjects with excessive erythrocytosis was small, yet consistent and potentially important, as it remained below the threshold known for theincrease in erythropoietin stimulation. This may be an important factor promoting erythropoiesis, but its relevance needs to be further explored.

This article has been cited by other articles:

				G. F. Gonzales, M. Gasco, V. Tapia, and C. Gonzales-Castaneda High serum testosterone levels are associated with excessive erythrocytosis of chronic mountain sickness in men Am J Physiol Endocrinol Metab, June 1, 2009; 296(6): E1319 - E1325. [Abstract] [Full Text] [PDF]

				V. E. Claydon, G. Gulli, M. Slessarev, O. Appenzeller, G. Zenebe, A. Gebremedhin, and R. Hainsworth Cerebrovascular Responses to Hypoxia and Hypocapnia in Ethiopian High Altitude Dwellers Stroke, February 1, 2008; 39(2): 336 - 342. [Abstract] [Full Text] [PDF]

				J.-P. Richalet, M. Rivera, P. Bouchet, E. Chirinos, I. Onnen, O. Petitjean, A. Bienvenu, F. Lasne, S. Moutereau, and F. Leon-Velarde Acetazolamide: A Treatment for Chronic Mountain Sickness Am. J. Respir. Crit. Care Med., December 1, 2005; 172(11): 1427 - 1433. [Abstract] [Full Text] [PDF]