Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04915378 |
Other study ID # |
01-2021-SU-HAST |
Secondary ID |
|
Status |
Completed |
Phase |
|
First received |
|
Last updated |
|
Start date |
June 1, 2021 |
Est. completion date |
May 31, 2022 |
Study information
Verified date |
June 2022 |
Source |
University of Zurich |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
The predictive value of the hypoxia altitude simulation test (HAST) or other baseline values
to predict altitude-related adverse health effects (ARAHE) is not established. To address
this gap, the main goals of this investigation will be 1) to evaluate the diagnostic accuracy
of the HAST in identifying individuals that will experience ARAHE during altitude travel and
2) to establish prediction models incorporating other commonly assessed clinical
characteristics either alone or in combination with the HAST as predictors of ARAHE in
altitude travelers.
Hypotheses: In lowlanders with COPD, a PaO2 <6.6 kPa or another cutoff of PaO2 or SpO2 at the
end of the HAST, at rest or during exertion and/or clinical variables including symptoms,
pulmonary function indices, 6-min walk distance (6MWD), either alone or combined to a
multivariable model, will predict ARAHE during a sojourn of 2 days at 3100m with accuracy
greater than chance
Description:
Altitude or air travel has become increasingly popular for recreational and professional
reasons. Chronic obstructive pulmonary disease (COPD) affects up to 12% of adults worldwide
and is associated with progressive hypoxemia, especially during exercise, due to respiratory
mechanical constraints, airway obstruction and increasing pulmonary hypertension (PH). COPD
patients are at increased risk of ARAHE including acute mountain sickness (AMS) and severe
hypoxemia. Factors assessed at lowland that would predict ARAHE of COPD patients exposed to a
hypobaric hypoxic environment at altitude or during air travel would be highly warranted.
During the HAST COPD-patients are exposed to an inspiratory oxygen fraction (FiO2) of 15.1%
corresponding to an altitude of ≈ 2500m and this test was designed to predict deoxygenation
at altitude. The predictive value of the HAST or other baseline values to predict ARAHE is
not established. To address this gap, the main goals of this investigation will be 1) to
evaluate the diagnostic accuracy of the HAST in identifying individuals that will experience
ARAHE during altitude travel and 2) to establish prediction models incorporating other
commonly assessed clinical characteristics either alone or in combination with the HAST as
predictors of ARAHE in altitude travelers.
For this diagnostic accuracy study, COPD-patients with an FEV1 40-80% predicted living < 1000
m without severe hypoxemia (SpO2, <92%), hypercapnia (PaCO2 >6 kPa) or comorbidities will be
recruited to traveling to and staying for two nights at 3100 m. At 760 m, the HAST will be
performed, at 760 m and 3100 m symptoms, vital signs, SpO2, pulmonary function tests, 6MWD,
sleep studies will be repetitively assessed. ARAHE will be defined if one of the following
present: AMS with a Lake Louise questionnaire score >4 including headache, or AMSc score
≥0.7, resting SpO2 <80% >30 min or <75% for >15 min; or exercise SpO2 <75% for >5 min
accompanied by symptoms, any intercurrent illness including infections, hypertension,
neurologic impairments, dyspnea or discomfort at rest requiring oxygen treatment, chest pain
and/or ECG signs of cardiac ischemia.