Reducing the Pro-ischaemic Effects of Air Pollution Exposure Using a Simple Face Mask

March 30, 2010 updated by: University of Edinburgh

Reducing the Pro-ischaemic Effects of Ambient Particulate Air Pollution in Patients With Coronary Heart Disease Using a Simple Face Mask Intervention

Air pollution is a major cause of cardiorespiratory morbidity and mortality. The exact components of air pollution that underlie the cardiovascular effects are not yet known, but combustion-derived particulate matter is suspected to be the major cause. Epidemiological studies have shown that exposure to air pollution causes exacerbation of existing cardiorespiratory conditions leading to increased hospital admissions and death. The investigators have recently conducted a series of controlled exposure studies to urban particulate matter and diesel exhaust in healthy volunteers and patients with coronary heart disease. The investigators found that controlled exposure to dilute diesel exhaust in patients with prior myocardial infarction induced asymptomatic myocardial ischaemia with an increase in electrocardiographic measures of myocardial ischaemia. Whilst important, further questions remain: (i) does air pollution exposure exacerbate ischaemia and reduce exercise tolerance in patients with symptomatic angina pectoris, (ii) do "real world" exposures as encountered in the urban environment of major cities have similar effects, and (iii) can a simple face mask intervention to reduce exposure to particulate air pollution improve health outcomes in patients with coronary heart disease?

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

100 patients with stable angina pectoris will be recruited from the HPS-THRIVE cohort or from the cardiology outpatient department at the Fuwai Hospital in Beijing. Patients will attend the department first thing in the morning on two occasions, separated by at least 1 week. All subjects will be fitted with a 12-lead Holter monitor and 24-hour ambulatory blood pressure monitor. They will be issued with a diary to record their activities and symptoms.

Patients will be randomised to wear a simple facemask for one of their visits (3M Dust Respirator 8812). When randomised to wear a mask, subjects will be asked to wear the mask as much as possible in the 24 hours prior to the study day and for the 24 hours of the study day (48 hours in total). Subjects will be instructed to wear the mask at all times when outdoors, and as much as possible when indoors.

On both visits, patients will be asked to walk along a prespecified route for 2 hours in a city centre location in Beijing. During this period patients will walk at their own pace for 15 mins and rest for 5 mins for a total of 120 mins (6 cycles). After the walk, subjects will return to the department and the pollution equipment switched off. A formal BRUCE protocol exercise stress test will be performed as soon as possible after finishing the 2-hour walk, and blood tests will be taken just prior to the exercise stress test (10-20mls in total). Subjects will be asked to wear the ambulatory blood pressure monitor and the Holter ECG monitor for a total of 24 hours, returning the following day to have this removed. Personal exposure to air pollution will be determined during the 2 hour walk with a series of monitors contained within a small backpack.

Study Type

Interventional

Enrollment (Anticipated)

100

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
      • Beijing, China
        • Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Medical Union College

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Stable coronary heart disease
  • Symptoms of angina pectoris
  • Evidence of coronary heart disease by angiography or by exercise stress testing

Exclusion Criteria:

  • Current smokers
  • History of arrhythmia
  • Severe 3 vessel coronary heart disease or left main stem stenosis that has not been revascularised
  • Resting conduction abnormality
  • Digoxin therapy
  • Uncontrolled hypertension
  • Renal failure
  • Hepatic failure
  • Acute coronary syndrome or unstable symptoms within 3 months
  • Significant occupation exposure to air pollution

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Visit 1
2 hour walk in city centre location in Beijing China
Device: No Face Mask
Subjects will not wear a face mask to reduce their personal air pollution exposure
Experimental: Visit 2
2 hour walk in city centre location in Beijing China
Device: Face Mask
Subjects will be asked to wear a simple face mask to reduce personal exposure to particulate air pollution. Subjects will be asked to wear the mask for 24 hours prior to the study day and the 24 hours of the study day. They will be instructed to wear the mask at all times when outdoors and as much as possible when indoors.
Other Names:
  • 3M Dust Respirator 8812

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Myocardial ischaemic burden determined using continuous electrographic monitoring
Time Frame: During 2 hour walk and subsequent 24 hour period
During 2 hour walk and subsequent 24 hour period

Secondary Outcome Measures

Outcome Measure
Time Frame
Symptoms of angina pectoris assessed by patient diary and GTN use
Time Frame: During 2 hour walk and subsequent 24 hour period
During 2 hour walk and subsequent 24 hour period
Biochemical markers of myocardial ischaemia
Time Frame: After 2 hour city centre walk
After 2 hour city centre walk
Systemic inflammatory markers
Time Frame: After 2 hour city centre walk
After 2 hour city centre walk
Blood pressure
Time Frame: During 2 hour walk and for subsequent 24 hours
During 2 hour walk and for subsequent 24 hours
Heart rate and heart rate variability
Time Frame: During 2 hour walk and subsequent 24 hour period
During 2 hour walk and subsequent 24 hour period
Personal exposure to air pollutants
Time Frame: During 2 hour walk
During 2 hour walk
Exercise capacity, time to symptoms and time to 1mm ST segment depression on standard treadmill exercise testing
Time Frame: Immediately after 2 hour city centre walk
Immediately after 2 hour city centre walk

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Edinburgh

Collaborators

Chinese Academy of Medical Sciences, Fuwai Hospital

Investigators

  • Principal Investigator: Lixin Jiang, MD, Chinese Academy of Medical Sciences and Peking Medical Union College

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

January 1, 2009

Primary Completion (Actual)

May 1, 2009

Study Completion (Actual)

May 1, 2009

Study Registration Dates

First Submitted

December 15, 2008

First Submitted That Met QC Criteria

December 16, 2008

First Posted (Estimate)

December 17, 2008

Study Record Updates

Last Update Posted (Estimate)

March 31, 2010

Last Update Submitted That Met QC Criteria

March 30, 2010

Last Verified

May 1, 2009

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 167/2008/Patient

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Angina Pectoris

Clinical Trials on No Face Mask

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Jamaica

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe