Skydiving as a Model of Psychological Stress and Its Effect on Intestinal Barrier Function

In this study, it will be investigated how psychological stress evoked by skydiving affects the intestinal permeability in 20 healthy subjects. Participants attend two visits: 1) Skydiving visit, 2) Negative control visit. At all visits, saliva samples, blood samples, and faecal samples are collected, and the multi-sugar permeability test is performed. In this test, participants drink a sugar solution and then collect urine for 5 and 24 h. The ratio of the sugars detected in the urine is a reflection of the intestinal permeability. Saliva samples are collected for assessment of cortisol, a stress marker. Blood and faecal samples are collected for assessment of markers of intestinal barrier function and inflammation.

Study Overview

• Status: Completed
• Conditions: Psychological Stress Due to Skydiving
• Intervention / Treatment: Other: Skydiving

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Sweden
  • Örebro, Sweden, 701 82
    • Örebro University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Written informed consent prior to any study related procedures
2. Age > 18 till <50
3. Novice skydivers (first or second tandem jump)
4. Signed up for tandem skydive
5. Willing to abstain from probiotic products or medications known to alter gastrointestinal function throughout the study

Exclusion Criteria:

1. Abdominal surgery which might influence gastrointestinal function, except appendectomy and cholecystectomy.
2. Current diagnosis of hypertension.
3. Current diagnosis of psychiatric disease.
4. Over 100kg or with a body mass index over 35.
5. Systemic use of steroids in the last 6 weeks.
6. Use of antibiotics or antimicrobial medication in the last month.
7. Daily usage of non-steroidal anti-inflammatory drugs in the last 2 months or incidental use in the last 2 weeks prior to screening.
8. Usage of medications that could affect the barrier function, except oral contraceptives, during the 14 days prior to screening.
9. Diagnosed inflammatory gastrointestinal disease.
10. Regular use of probiotics in the last 6 weeks.
11. Smoking and/or chewable tobacco.
12. Planned changes to current diet or exercise regime.
13. Use of laxatives, anti-diarrhetics, anti-cholinergics within last 4 weeks prior to screening.
14. Use of immunosuppressant drugs within last 4 weeks prior to screening.
15. Women: Pregnancy, lactation.
16. Abuse of alcohol or drugs.
17. Any disease/condition which in the investigator's opinion could interfere with the intestinal barrier function.
18. Any clinically significant disease/condition which in the investigator's opinion could interfere with the results of the trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Skydiving; Tandem skydiving	Other: Skydiving; Tandem skydiving (with an experienced instructor)
No Intervention: Negative control; No skydiving

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change in small intestinal permeability after skydiving measured as the urinary lactulose/rhamnose secretion ratio compared to negative control	2-4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in whole gut permeability after skydiving measured as the urinary sucralose/erythritol secretion ratio compared to negative control		2-4 weeks
Change in colonic permeability after skydiving measured as the urinary sucralose/erythritol secretion ratio compared to negative control		2-4 weeks
Change in gastroduodenal permeability after skydiving measured as urinary sucrose excretion		2-4 weeks
Change in quantity of intestinal permeability markers in blood after skydiving compared to the negative control	fatty acid binding proteins, zonulin, claudin-3, 16S rRNA	2-4 weeks
Change in salivary cortisol levels after skydiving compared to the negative control		2-4 weeks

Collaborators and Investigators

• Sponsor: Örebro University, Sweden

Publications and helpful links

General Publications

• Roca Rubio MF, Eriksson U, Brummer RJ, König J. Short intense psychological stress induced by skydiving does not impair intestinal barrier function. PLoS One. 2021 Jul 8;16(7):e0254280. doi: 10.1371/journal.pone.0254280. eCollection 2021.

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2018
• Primary Completion (Actual): October 31, 2018
• Study Completion (Actual): October 31, 2018

Study Registration Dates

• First Submitted: August 21, 2018
• First Submitted That Met QC Criteria: August 22, 2018
• First Posted (Actual): August 23, 2018

Study Record Updates

• Last Update Posted (Actual): January 3, 2019
• Last Update Submitted That Met QC Criteria: January 2, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Behavioral Symptoms; Stress, Psychological
• Other Study ID Numbers: 2017/313

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: No individual participant data will be shared.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No