Effect of High Altitude Exposure, Acclimatization and Re-exposure on Nocturnal Breathing Pattern in Lowlanders

Prospective interventional trial in lowlanders evaluating the effect of acute exposure, acclimatization and re-exposure of high altitude on nocturnal breathing pattern.

Study Overview

• Status: Completed
• Conditions: Effect of High Altitude
• Intervention / Treatment: Other: Altitude exposure

Detailed Description

Respiratory polygraphies will be performed in Santiago de Chile, 520 m, over the course of 3 days. Participants will then travel by commercial airline (5 h flight) and by bus (3 h ride) to the ALMA base camp located at 2900 m near San Pedro de Atacama, northern Chile. Participants will stay there for the next 7 nights and respiratory polygraphies will be performed on night 1 and 6. They will be spend the days (6-8 h daily) at the telescope station at 5050 m while undergoing physiological testing. Daily transports from 2900 to 5050 m will be by car (1 h ride, one way). After the first 8 day altitude sojourn participants will return to the Santiago area (520 m) for a 6 day recovery period.

A second altitude sojourn with an identical schedule as the one described above and a final low altitude stay of 3 days will follow.

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich, Switzerland, 8091
    • University of Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• born, raised and currently living <800m
• No overnight stay at altitudes >1500 m 4 weeks before the study

Exclusion Criteria:

• Previous altitude intolerance to altitude <3000 m
• Pregnancy
• Health impairment, which requires regular treatment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Altitude exposure; Acute high altitude exposure followed by 8 day acclimatization and re-exposure after 6 days at low altitude	Other: Altitude exposure; Altitude exposure

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean nocturnal oxygen saturation measured by pulse oximetry	Change in mean nocturnal oxygen saturation over the course of high altitude exposure during 2 sojourns at 5050 m compared to low altitude	first sojourn at 5050 m, night 1, 6; second sojourn at 5050 m, night 1, 6; low altitude sojourn at 520 m, night 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Apnea-/hypopnea index measured by respiratory polygraphy	Change in apnea-/hypopnea index over the course of high altitude exposure during 2 sojourns at 5050 m compared to low altitude	first sojourn at 5050 m, night 1, 6; second sojourn at 5050 m, night 1, 6; low altitude sojourn at 520 m, night 1
Oxygen desaturation index measured by respiratory polygraphy	Change in oxygen desaturation index over the course of high altitude exposure during 2 sojourns at 5050 m compared to low altitude	first sojourn at 5050 m, night 1, 6; second sojourn at 5050 m, night 1, 6; low altitude sojourn at 520 m, night 1
Acute mountain sickness measured by the Environmental Symptom questionnaire cerebral score (AMSc)	Incidence of acute mountain sickness (AMSc score >= 0.7) over the course of high altitude exposure during 2 sojourns at 5050 m compared to low altitude	first sojourn at 5050 m, day 2, 7; second sojourn at 5050 m, day 2,7; low altitude sojourn at 520 m, day 2

Collaborators and Investigators

• Sponsor: University of Zurich
• Collaborators: University of Calgary

Study record dates

Study Major Dates

• Study Start (ACTUAL): April 4, 2016
• Primary Completion (ACTUAL): May 7, 2016
• Study Completion (ACTUAL): May 7, 2016

Study Registration Dates

• First Submitted: March 31, 2016
• First Submitted That Met QC Criteria: March 31, 2016
• First Posted (ESTIMATE): April 6, 2016

Study Record Updates

• Last Update Posted (ACTUAL): November 13, 2018
• Last Update Submitted That Met QC Criteria: November 8, 2018
• Last Verified: November 1, 2018

More Information

Terms related to this study

• Keywords: Altitude; Nocturnal breathing pattern
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Respiratory Aspiration; Altitude Sickness
• Other Study ID Numbers: REB15-2709_V1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO