Evaluation of a Novel Indoor Air Pollution Intervention Among Older Adults

Particulate matter (PM) air pollution is the leading risk factor of global disease burden and the largest environmental risk factor for premature death and cardiovascular disease (CVD). Older adults are particularly susceptible to air pollution exposures and the development of CVD as they often have underlying health conditions. PM levels are rising in the Western United States (US) as wildfires have increased, with up to 50% of fine PM (PM2.5; particles <2.5 µm in diameter) in some Western regions now attributed to wildfires. Recent research indicates there is often a substantial increase in indoor PM2.5 when outdoor PM2.5 increases, including during wildfire events. Improving indoor air quality is critically important as US adults spend 90% of their time indoors where air quality is impacted by numerous indoor and outdoor air pollution sources. New strategies are needed to improve indoor air quality and CVD health outcomes, particularly as the US population rapidly ages and the number of susceptible older adults grows. There is evidence that filtering indoor air with portable air cleaners (PACs) can result in short-term PM2.5 improvements. However, evidence is limited that PAC use meaningfully improves health, particularly in studies of longer duration. In response to this need, the investigators have developed a household indoor air quality intervention called AIRWISE (Air Improvement and Real-time Monitoring for Wellness through Interactive Strategies and Education). AIRWISE promotes sustained improvements in indoor air quality through education, behavioral cues, and equipment including PACs and PM2.5 sensors that display real-time data. In this project, the investigators will evaluate the AIRWISE intervention among older adults in the wildfire-impacted US state of Montana. In Aim 1, the investigators will conduct a randomized trial to test the efficacy of the AIRWISE intervention on PREVENT (Predicting Risk of CVD EVENTs), a validated CVD risk score. The central hypothesis is that PREVENT will be improved among older adults who use AIRWISE compared to controls who use only PACs. The rationale is that the AIRWISE intervention will promote sustained improvements in indoor air quality and CVD risk, a significant advance beyond PACs alone that are widely recommended yet have inconsistent benefits on long-term health. In Aim 2, the investigators will use Aim 1 data to determine associations between indoor PM2.5 concentrations and PREVENT. The investigators will use additional models between PM2.5 and the individual components of PREVENT as outcomes in order to determine which risk factors are most impacted by PM2.5 and inform underlying subclinical mechanisms. In Aim 3, the investigators will model the economic costs and benefits of indoor PM2.5 improvements and the AIRWISE intervention to inform policy-level action. With the converging threats of increasing air pollution due to wildfires and an aging US population, this project will contribute to identifying actionable strategies to improve indoor air quality and decrease CVD risk among older adults.