Condition category
Signs and Symptoms
Date applied
05/05/2015
Date assigned
07/05/2015
Last edited
11/05/2015
Prospective/Retrospective
Prospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Air pollution can seriously affect people’s health; young children and older adults are particularly vulnerable to its effects. Air pollution, which mainly comes from traffic exhaust fumes, can cause breathing and heart problems and has been linked to disease and early death. Older adults are encouraged to be physically active and carry out daily activities such as walking, cycling and taking part in sports to maintain their health. However, many physical activities are performed outdoors. Normally, outdoor activities are a healthy way to keep fit, but when air pollution levels are high, outdoor exercise may have a negative effect on a person’s health. The Air Quality Health Index (AQHI) is a health risk communication tool which provides information on current and forecast air quality conditions. The AQHI tool provides advice to guide outdoor activities and to reduce the risk of adverse health effects from exposure to high levels of air pollution. This study aims to test whether following AQHI advice is effective in reducing the risk of adverse health effects of air pollution in healthy older adults.

Who can participate?
Healthy adults 55 years and older.

What does the study involve?
Participants are randomly allocated into one of two groups. Those in group 1 (intervention group) are asked to exercise every day, but to exercise indoors rather than outdoors when the forecast AQHI value is 5 or greater. Those in group 2 (control group) are asked to exercise outdoors daily. All participants complete 10 weeks of daily health measures before and after exercise at home. Health measures are also carried out every week at a central site for the duration of the study.

What are the possible benefits and risks of participating?
Participants will not benefit directly from participating in this study; however there is financial compensation at the completion of data collection. This study will entail a moderate time commitment of approximately 1 ½ hours per day and 4 hours once per week for 10 weeks. Clinical tests may cause some discomfort, however, any discomfort should be brief and transient. Some participants may experience some skin irritation at the electrode sites, but this reaction will disappear.

Where is the study run from?
University of Western Ontario (Canada)

When is the study starting and how long is it expected to run for?
Feb 2015 to August 2016

Who is funding the study?
Health Canada (Canada)

Who is the main contact?
Dr D Stieb
dave.stieb@hc-sc.gc.ca

Trial website

Contact information

Type

Public

Primary contact

Dr David Stieb

ORCID ID

Contact details

445-757 West Hastings St. - Federal Tower
Vancouver
V6C 1A1
Canada
604 666 3701
dave.stieb@hc-sc.gc.ca

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

810438

Study information

Scientific title

A randomised controlled trial of the effectiveness of the Air Quality Health Index (AQHI) in reducing cardiac and respiratory adverse effects of air pollution in adults 55 and over

Acronym

Study hypothesis

Reducing outdoor physical activity in accordance with advice provided through the Air Quality Health Index will reduce adverse cardiac and respiratory effects of air pollution in adults 55 and over.

Ethics approval

Health Canada/Public Health Agency of Canada, 23/04/2015, ref: 2012-0035.

Study design

Single centre randomised trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Community

Trial type

Prevention

Patient information sheet

Not available in web format, please use contact details to request a participant information sheet.

Condition

Cardiac and respiratory health

Intervention

1. The intervention group will be asked to exercise indoors rather than outdoors and avoid other outdoor activity prior to physiological testing when the maximum AQHI is forecast to be 5 or higher (on the remaining days they will exercise outdoors). The intervention group will receive instructions for a simple indoor exercise routine that can be completed on designated days.
2. The control group will exercise outdoors daily

Intervention type

Behavioural

Phase

Drug names

Primary outcome measures

Weekly measures before and after 30 minutes of mild activity:
1. Heart rate variability (Holter monitoring)
2. Endothelial function (Reactive Hyperemia Index - Peripheral artery tone)
3. Oxygen saturation (finger oximeter)
4. Blood pressure (automated sphygmomanometer)
5. Fraction of exhaled Nitric Oxide (exhaled NO sensor)
6. Spirometric measures (spirometer)
7. Urinary oxidative stress markers (vascular endothelial growth factor (VEGF), 8-isoprostane, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG))

Secondary outcome measures

Respiratory symptoms.

Overall trial start date

01/02/2015

Overall trial end date

31/08/2016

Reason abandoned

Eligibility

Participant inclusion criteria

1. Participants must be 55 years of age or older
2. Non-smokers
3. Not exposed to environmental tobacco smoke at home
4. No seasonal allergies

Participant type

Healthy volunteer

Age group

Senior

Gender

Both

Target number of participants

80

Participant exclusion criteria

1. Unstable angina
2. Atrial flutter
3. Atrial fibrillation
4. Paced rhythm
5. Left bundle branch block
6. Implanted cardioverter-defibrillator (ICD)
7. Participants with allergies to latex or adhesives will be excluded

Recruitment start date

18/05/2015

Recruitment end date

30/06/2015

Locations

Countries of recruitment

Canada

Trial participating centre

University of Western Ontario
1151 Richmond St
London
N6A 3K7
Canada

Sponsor information

Organisation

Health Canada

Sponsor details

50 Colombine Drwy
Tunney's Pasture
Ottawa
K1A 0K9
Canada

Sponsor type

Government

Website

Funders

Funder type

Government

Funder name

Health Canada

Alternative name(s)

Santé Canada

Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government

Location

Canada

Results and Publications

Publication and dissemination plan

Papers will be submitted to peer reviewed journals regarding primary study findings and possibly secondary findings regarding effect modification by genotype. It is estimated that the first paper will be submitted in summer 2016.

Intention to publish date

01/12/2016

Participant level data

Not expected to be available

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes