NCT04024852

Air Pollution, Physical Activity and Cardiovascular Function of Patients With Implanted Cardioverter Defibrillators

Air Pollution, Physical Activity and Cardiovascular Function of Patients With Implanted Cardioverter Defibrillators: A Randomized Controlled Trial of Indoor Versus Outdoor Activity

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 18 (actual)
• Sponsor: Health Canada · Other Government
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study investigated whether patients with an implanted cardioverter defibrillator (ICD) who followed advice to exercise indoors on high air pollution days had reduced adverse impacts on cardiovascular measures compared with those who exercised outdoors on those days. Participants were randomly divided into the control and intervention groups. Both groups walked for 30 minutes outdoors every day for maximum 70 days, and their blood pressure, pulse rate and blood oxygen saturation pre- and post-exercise were measured. Hourly ambient concentrations of air pollutants were collected. On days forecast with Air Quality Health Index was equal to or higher than 5, the intervention group was advised to exercise indoors.

Detailed description

Background: The Air Quality Health Index (AQHI) is a risk communication tool intended to provide information to the public on current and forecast air quality conditions. It was developed by the Canadian government to help the public make decisions to limit short-term exposure to air pollution and adjust their activity when air pollution levels are high, particularly for people who are sensitive to air pollution. Little research has been done to characterize the benefits of following AQHI advice. The AQHI is based on a weighted sum of concentrations of nitrogen dioxide (NO2), ozone (O3), and particulate matter of median aerodynamic diameter ≤ 2.5 µm (PM2.5) to provide information to the public on current and forecasted air quality conditions. Objective: This study investigated whether patients with an implanted cardioverter defibrillator (ICD) who followed advice to exercise indoors on high AQHI days had reduced adverse impacts on cardiovascular measures compared with those who exercised outdoors on those days. Methods: Participants with ICD were randomly divided into the control and intervention group. Both groups did daily 30-minute walked outdoors for maximum 70 days, and their data on blood pressure, pulse rate and blood oxygen saturation pre- and post-exercise were collected. Hourly ambient concentrations of PM2.5, O3, NO2, sulphur dioxide (SO2) and carbon monoxide (CO) were collected, and AQHI calculated. On days forecast with AQHI ≥5, the intervention group was advised to exercise indoors. Mixed-effects models were applied to analyze the associations between air pollution and cardiovascular measures.

Conditions

• Blood Pressure

Interventions

Type	Name	Description
OTHER	Intervention group	When Air Quality Health Index is below level 5, the intervention group did daily mild exercise (walking) outdoors for 30 minutes. When Air Quality Health Index is equal to or above level 5, the group is advised to do mild exercise indoors for 30 minutes.

Timeline

• Start date: 2016-05-30
• Primary completion: 2017-12-08
• Completion: 2019-07-01
• First posted: 2019-07-18
• Last updated: 2019-07-18