NCT05016414

Brief Summary

This study is being done to prevent changes in the vision of astronauts during prolonged residence on the International Space Station or a mission to Mars. This project will provide data about the efficacy of lower body negative pressure to mimic daily upright posture by intermittently lowering central venous pressure while in simulated microgravity (3 days of bed rest). The investigators expect that 3 days of bed rest will increase choroid thickness, and choroid area. The investigators hypothesize that nightly LBNP (-20mmHg) will prevent these changes.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
10

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Mar 2019

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

March 1, 2019

Completed
1 year until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2020

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 1, 2020

Completed
1.4 years until next milestone

First Submitted

Initial submission to the registry

August 9, 2021

Completed
14 days until next milestone

First Posted

Study publicly available on registry

August 23, 2021

Completed
Last Updated

September 8, 2021

Status Verified

August 1, 2021

Enrollment Period

1 year

First QC Date

August 9, 2021

Last Update Submit

August 31, 2021

Conditions

Outcome Measures

Primary Outcomes (2)

  • Change in choroid area

    The change in choroid area measured by optical coherence tomography.

    Baseline, after 3-days of bed rest

  • Change in choroid volume

    The change in choroid volume measured by optical coherence tomography.

    Baseline, after 3-days of bed rest

Study Arms (2)

Control

NO INTERVENTION

4 days of strict bed rest

Lower body negative pressure

EXPERIMENTAL

4 days of strict bed rest with nightly lower body negative pressure at -20mmHg

Other: Lower body negative pressure

Interventions

lower body negative pressure at -20mmHg delivered via a custom designed sleeping sack

Lower body negative pressure

Eligibility Criteria

Age18 Years - 55 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • age 18-55

You may not qualify if:

  • cardiovascular disease
  • ophthalmological disease

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

UT Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

Related Publications (1)

  • Hearon CM Jr, Peters K, Dias KA, Macnamara JP, Marshall JET, Campain J, Martin D, Marshal-Goebel K, Levine BD. Assessment of venous pressure by compression sonography of the internal jugular vein during 3 days of bed rest. Exp Physiol. 2023 Dec;108(12):1560-1568. doi: 10.1113/EP091372. Epub 2023 Oct 12.

MeSH Terms

Conditions

spaceflight-induced visual impairment

Interventions

Lower Body Negative Pressure

Intervention Hierarchy (Ancestors)

DecompressionTherapeutics

Study Officials

  • Benjamin Levine, MD

    University of Texas Southwestern Medical Center

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
OUTCOMES ASSESSOR
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor of Medicine

Study Record Dates

First Submitted

August 9, 2021

First Posted

August 23, 2021

Study Start

March 1, 2019

Primary Completion

March 1, 2020

Study Completion

March 1, 2020

Last Updated

September 8, 2021

Record last verified: 2021-08

Data Sharing

IPD Sharing
Will not share

Locations