Early Signs of Altitude Illness in Patients With COPD

Self-Monitoring for Early Signs of Altitude Illness in Patients With Chronic Obstructive Pulmonary Disease. A Diagnostic Test Accuracy Study.

This study evaluates whether structured self-monitoring (SSM) by a symptom checklist in combination with a pulse oximeter worn at the wrist allows lowlanders with COPD to accurately identify whether or not they will experience an altitude-related illness during altitude travel.

Study Overview

• Status: Completed
• Conditions: Chronic Obstructive Pulmonary Disease
• Intervention / Treatment: Diagnostic test: Structured self-monitoring during an altitude ascent and stay at high altitude

Detailed Description

This study evaluates whether structured self-monitoring (SSM) by a symptom checklist in combination with a pulse oximeter worn at the wrist allows lowlanders with COPD to accurately identify whether or not they will experience an altitude-related illness during altitude travel. After baseline evaluation at 760 m, patients will travel by bus within 3-5 h to the Tuja Ashu high altitude clinic at 3'100 m and stay there for 2 days. During this period, participants will perform SSM. They are instructed to report to study personnel if they fulfill predefined criteria for impeding altitude-related illness.

A planned interim analysis will be performed after the first year of the study or after completion of study by 80 participants, whichever comes first to allow any necessary adaptations of the sample size or terminate the study early for futility or high accuracy of the index test.

• Study Type: Observational
• Enrollment (Actual): 153

Contacts and Locations

Study Locations

• Kyrgyzstan
  • Bishkek, Kyrgyzstan
    • National Center of Cardiology and Internal Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients with COPD, FEV1 40-80% predicted living at low altitude.

Description

Inclusion criteria

• Male and female patients, age 18-75 yrs.
• COPD diagnosed according to GOLD, FEV1 40-80% predicted, SpO2 ≥92%, PaCO2 <6 kPa at 760 m.
• Born, raised and currently living at low altitude (<800 m).
• Written informed consent.

Exclusion criteria

• COPD exacerbation, very severe COPD with hypoxemia at low altitude (FEV1 <40% predicted; oxygen saturation on room air <92% or hypercapnia at 760 m).
• Other lung disease or disorder of control of breathing
• Comorbidities such as uncontrolled cardiovascular disease, i.e., unstable systemic arterial hypertension, coronary artery disease; previous stroke, internal, neurologic, rheumatologic or psychiatric disease that interfere with protocol compliance including current heavy smoking (>20 cigarettes per day)

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
COPD patients	Diagnostic test: Structured self-monitoring during an altitude ascent and stay at high altitude; Structured self-monitoring by a symptom checklist in combination with a pulse oximeter worn at the wrist in lowlanders with COPD ascending from low altitude (760m) to high altitude (3100m).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accurarcy measures of structured self-monitoring	Diagnostic performance includes sensitivity, specificity, positive and negative predictive values, and receiver operator curve area under the the curve. The diagnostic performance will be compared statistically using c-statistics against the reference test. Reference test will be the occurence of altitude-related illness defined as the following: AMS defined by the Lake Louise questionnaire score or with AMSc score; severe hypoxemia (SpO2 <80% at rest >30 min; or SpO2 <75% at rest >15 min;; intercurrent illness that cannot be relieved by simple measures such as paracetamol 3x500 mg/day, inhalation of bronchodilators.; dyspnea or discomfort at rest requiring treatment with oxygen; chest pain or ECG signs of cardiac ischemia; severe hypertension: systolic blood pressure >200 mmHg, diastolic blood pressure >110 mmHg; new onset neurologic impairment; Any condition that requires study withdrawal according to the decision of the independent physician	Day 1 to 3 at 3100m

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Acute mountain sickness severity assessed by the Lake Louise score	The severity of acute mountain sickness will be assessed by the Lake Louise questionnaire. The severity will be calculated when the presence of headache and at least one of the following symptoms is present: gastrointestinal upset, fatigue or weakness and dizziness or lightheadedness. Each of the four questions is asked with the corresponding 0 to 3 rating of the response (0 = Not present, 1 = mild, 2 = moderate, 3 = severe). The sum of the responses on these questions is then calculated, resulting in the AMS severity.	Day 1 to 3 at 3100m
Altitude-related illness, incidence	Incidence of ARI during the stay at 3100 m. ARI is defined as the following: AMS defined by the Lake Louise questionnaire score or with AMSc score; severe hypoxemia (SpO2 <80% at rest >30 min; or SpO2 <75% at rest >15 min;; intercurrent illness that cannot be relieved by simple measures such as paracetamol 3x500 mg/day, inhalation of bronchodilators.; dyspnea or discomfort at rest requiring treatment with oxygen; chest pain or ECG signs of cardiac ischemia; severe hypertension: systolic blood pressure >200 mmHg, diastolic blood pressure >110 mmHg; new onset neurologic impairment; Any condition that requires study withdrawal according to the decision of the independent physician	Day 1 to 3 at 3100m
Spirometric measurement of forced expiratory volume in one second	Altitude-induced change in the forced expiratory volume in one between 760 and 3100m	Day 2 at 760 and 3100m
Arterial partial pressure of oxygen	Altitude-induced change in arterial partial pressure of oxygen assessed by arterial blood gas puncture at 760 and 3100m	Day 2 at 760 and 3100m
Six-minute walk distance in meters	Altitude-induced change in the six-minute walk distance assessed by the six-minute walk test performed at 760 and 3100m	Day 2 at 760 and 3100m
Changes in ST-Segment of the ECG during ergometry	Altitude-induced change in the ST-Segment of the ECG assessed during a maximal ergometry test performed at 760 and 3100m	Day 1 at 760 and 3100m

Collaborators and Investigators

• Sponsor: University of Zurich
• Collaborators: National Center of Cardiology and Internal Medicine named after academician M.Mirrakhimov

Study record dates

Study Major Dates

• Study Start (ACTUAL): May 20, 2019
• Primary Completion (ACTUAL): August 8, 2021
• Study Completion (ACTUAL): August 8, 2021

Study Registration Dates

• First Submitted: May 16, 2019
• First Submitted That Met QC Criteria: May 16, 2019
• First Posted (ACTUAL): May 21, 2019

Study Record Updates

• Last Update Posted (ACTUAL): November 29, 2022
• Last Update Submitted That Met QC Criteria: November 27, 2022
• Last Verified: November 1, 2022

More Information

Terms related to this study

• Keywords: Prevention; Altitude; Hypobaric hypoxia; Altitude-related illness
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive
• Other Study ID Numbers: 01-8/464-14

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No