Salbutamol, Pharmacogenetics and Breathing Mechanics

Bronchoconstriction Clinical Trial

Official title:

The Pharmacogenetic Effects of Inhaled Salbutamol on Breathing Mechanics and Cycling Performance

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01903785
• Other study ID #: H09-01154-A009
• Status: Completed
• Phase: Phase 4
• First received: July 8, 2013
• Last updated: October 31, 2016
• Start date: May 2013
• Est. completion date: August 2016

Study information

• Verified date: October 2016
• Source: University of British Columbia
• Contact: n/a
• Is FDA regulated: No
• Health authority: Canada: Health Canada
• Study type: Interventional

Clinical Trial Summary

Athletes using asthma medications called β2-agonists win a disproportionately high number of medals at Olympic Games. Due to a large variety in the genes that affect how individuals respond to β2-agonists, the investigators will look at variations in the genetic response to these medications by dividing athletes into high-responders and low-responders. The investigators will then compare athletic performance after the inhalation of β2-agonists to placebo. Furthermore, the investigators will analyze the effect of β2-agonists on breathing mechanics. Due to differences in their anatomy females may decrease the energy needed for breathing during high-intensity exercise to a greater extent compared to male athletes after the inhalation of β2-agonists.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 94
• Est. completion date: August 2016
• Est. primary completion date: December 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 19 Years to 45 Years

Eligibility

Inclusion Criteria:

• trained, experienced cyclists

• maximal oxygen consumption of at least 50ml/kg/min or 4l/min for women; and 60ml/kg/min or 5l/min for men

• athletes with and without exercise-induced bronchoconstriction

Exclusion Criteria:

• any uncontrolled heart or lung condition

• maximal oxygen consumption of less than 50ml/kg/min or 4L/min for women; and less than 60ml/kg/min or 5L/min for men

• pregnancy

• smoking

Study Design

Allocation: Randomized, Endpoint Classification: Pharmacodynamics Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Bronchoconstriction
• Cycling Performance
• Inhaled Salbutamol
• Respiratory Aspiration

Intervention

Drug:
• Salbutamol
60 minutes prior to the start of a 10km cycling time trial on a bike ergometer, subjects will inhale either 400ug of salbutamol 1600ug of salbutamol or 400ug of placebo in a randomly assigned manner in a single dose.
• Placebo

Locations

Country	Name	City	State
Canada	Environmental Physiology Laboratory, University of British Columbia	Vancouver	British Columbia

Sponsors (2)

Lead Sponsor	Collaborator
University of British Columbia	World Anti-Doping Agency (WADA)

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The effect of inhaled salbutamol on mean power output during cycling performance in female and male athletes	Athletes perform a two time trials, each on a separate day. The time trials are performed 60min after the inhalation of salbutamol or placebo.	Mean power output is assessed over the duration of a 10km time trial (start of time trial until completion of time trial) on a bike ergometer.	No
Primary	The effect of inhaled salbutamol on work of breathing (WOB) and expiratory flow limitation (EFL) in female and male athletes	EFL and WOB will be assessed with the help of an esophageal balloon and mouth pressure.	WOB and EFL will be assessed during an incremental exercise test. Exercise will start at 0 Watts and will then be increased every 2.5min by 30 Watts until maximal exertion.	No
Secondary	The effect of inhaled salbutamol on minute ventilation in asthmatic and non-asthmatic trained, female and male cyclists		Minute ventilation will be assessed during two 10km time trials (one time trial will be started 60min after the inhalation of salbutamol, the second time trial will be started 60min after the inhalation of placebo).	No