Residential Ventilation Systems and Filtration for Asthma Control in Adults

Cost-effective Approaches to Upgrading Residential Mechanical Ventilation Systems to Control Indoor Pollutants of Both Indoor and Outdoor Origin and Improve Asthma-related Health Outcomes

The goal of this study was to investigate the effectiveness of three common approaches to upgrading residential mechanical ventilation systems in existing homes for improving asthma-related health outcomes, reducing indoor pollutants of both indoor and outdoor origin, and maintaining adequate environmental conditions and ventilation rates in a cohort of adult asthmatics in existing homes in Chicago, IL.

The Breathe Easy Study utilized a quasi-randomized, within-subjects, parallel-group, pre-post intervention study design with four weeklong periods of indoor air quality (IAQ) and indoor environmental data collection for approximately one year before the installation of mechanical ventilation systems, followed by four weeklong periods of IAQ and indoor environmental data collection for approximately one year after the installation of mechanical ventilation systems, conducted from July 2017 through March 2020 in Chicago, IL. With the nature of a healthy home intervention study by installing residential mechanical ventilation systems within the timeframe, each participant received interventions in the middle of the study period, including continuous exhaust-only systems; intermittent powered central-fan-integrated-supply (CFIS) systems; or continuous balanced systems with an energy recovery ventilator. Thus, each participant served as their own control and there was no formal control group that did not receive intervention nor did they receive a sham/placebo intervention. Primary health outcome, asthma control, was assessed by using the Asthma Control Test (ACT) every month, and quality of life, stress, and other asthma-related health outcomes were assessed via the baseline and end-line surveys.

Inclusion Criteria:

• Age: 18 - 90+ years.
• English speaking and writing.
• Able to provide consent.
• Chicago resident.
• Households with at least one occupant with asthma
• Non-smoking houses
• Participant-owned houses
• Participant's agreement to surveys and IAQ monitoring over 2 years

Exclusion Criteria:

• Houses outside Chicago, IL USA
• Houses with significant health and safety issues