Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Mar 13;9(2):00488-2022.
doi: 10.1183/23120541.00488-2022. eCollection 2023 Mar.

Hypoxia-altitude simulation test to predict altitude-related adverse health effects in COPD patients

Meret Bauer  1   2 , Julian Müller  1   2 , Simon R Schneider  1   2 , Simone Buenzli  1   2 , Michael Furian  1   2 , Tanja Ulrich  1   2 , Arcangelo F Carta  1   2 , Patrick R Bader  1   2 , Mona Lichtblau  1   2 , Ajian Taalaibekova  2   3 , Madiiar Raimberdiev  2   3 , Benoit Champigneulle  2   4 , Talant Sooronbaev  2   3 , Konrad E Bloch  1   2 , Silvia Ulrich  1   2
Affiliations

Hypoxia-altitude simulation test to predict altitude-related adverse health effects in COPD patients

Meret Bauer et al. ERJ Open Res. .

Abstract

Background/aims: Amongst numerous travellers to high altitude (HA) are many with the highly prevalent COPD, who are at particular risk for altitude-related adverse health effects (ARAHE). We then investigated the hypoxia-altitude simulation test (HAST) to predict ARAHE in COPD patients travelling to altitude.

Methods: This prospective diagnostic accuracy study included 75 COPD patients: 40 women, age 58±9 years, forced expiratory volume in 1 s (FEV1) 40-80% pred, oxygen saturation measured by pulse oximetry (S pO2 ) ≥92% and arterial carbon dioxide tension (P aCO2 ) <6 kPa. Patients underwent baseline evaluation and HAST, breathing normobaric hypoxic air (inspiratory oxygen fraction (F IO2 ) of 15%) for 15 min, at low altitude (760 m). Cut-off values for a positive HAST were set according to British Thoracic Society (BTS) guidelines (arterial oxygen tension (P aO2 ) <6.6 kPa and/or S pO2 <85%). The following day, patients travelled to HA (3100 m) for two overnight stays where ARAHE development including acute mountain sickness (AMS), Lake Louise Score ≥4 and/or AMS score ≥0.7, severe hypoxaemia (S pO2 <80% for >30 min or 75% for >15 min) or intercurrent illness was observed.

Results: ARAHE occurred in 50 (66%) patients and 23 out of 75 (31%) were positive on HAST according to S pO2 , and 11 out of 64 (17%) according to P aO2 . For S pO2 /P aO2 we report a sensitivity of 46/25%, specificity of 84/95%, positive predictive value of 85/92% and negative predictive value of 44/37%.

Conclusion: In COPD patients ascending to HA, ARAHE are common. Despite an acceptable positive predictive value of the HAST to predict ARAHE, its clinical use is limited by its insufficient sensitivity and overall accuracy. Counselling COPD patients before altitude travel remains challenging and best focuses on early recognition and treatment of ARAHE with oxygen and descent.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: None declared.

Figures

FIGURE 1
FIGURE 1
The patient study inclusion flow is shown. HAST: hypoxia-altitude simulation test; SpO2: oxygen saturation measured by pulse oximetry; PaO2: arterial oxygen tension; BMI: body mass index.
FIGURE 2
FIGURE 2
Receiver operating characteristic (ROC) curves are shown for a) oxygen saturation measured by pulse oximetry (SpO2) and b) arterial oxygen tension (PaO2) at the end of the hypoxia-altitude simulation test (HAST), such as c) baseline resting SpO2 at low altitude before the HAST and d) the SpO2 at the peak 6-min walk distance (6MWD).
FIGURE 3
FIGURE 3
Boxplots of a) oxygen saturation measured by pulse oximetry (SpO2) and b) heart rate during the hypoxia-altitude simulation test (HAST) at the beginning (0 min) and at 3, 6, 9, 12 and 15 min are shown with the line indicating the mean, the box the 25th and 75th quartile and the whiskers revealing the extremes.
See this image and copyright information in PMC

References

    1. Tremblay JC, Ainslie PN. Global and country-level estimates of human population at high altitude. Proc Natl Acad Sci USA 2021; 118: e2102463118. doi: 10.1073/pnas.2102463118 - DOI - PMC - PubMed
    1. Varmaghani M, Dehghani M, Heidari E, et al. . Global prevalence of chronic obstructive pulmonary disease: systematic review and meta-analysis. East Mediterr Health J 2019; 25: 47–57. doi: 10.26719/emhj.18.014 - DOI - PubMed
    1. Griffo R, Spanevello A, Temporelli PL, et al. . Frequent coexistence of chronic heart failure and chronic obstructive pulmonary disease in respiratory and cardiac outpatients: evidence from SUSPIRIUM, a multicentre Italian survey. Eur J Prev Cardiol 2017; 24: 567–576. doi: 10.1177/2047487316687425 - DOI - PubMed
    1. Latshang TD, Kaufmann B, Nussbaumer-Ochsner Y, et al. . Patients with obstructive sleep apnea have cardiac repolarization disturbances when travelling to altitude: randomized, placebo-controlled trial of acetazolamide. Sleep 2016; 39: 1631–1637. doi: 10.5665/sleep.6080 - DOI - PMC - PubMed
    1. Lichtblau M, Latshang TD, Furian M, et al. . Right and left heart function in lowlanders with COPD at altitude: data from a randomized study. Respiration 2019; 97: 125–134. doi: 10.1159/000492898 - DOI - PubMed

LinkOut - more resources