Evaluation of a Novel Indoor Air Pollution Intervention Among Older Adults

Particulate matter air pollution is the leading environmental risk factor of cardiovascular disease and is increasing in the Western United States due to more frequent and severe wildfires. Older adults are particularly susceptible to both air pollution exposures and the development of cardiovascular disease, and the older adult population in the United States is rapidly growing. Given the converging threats of worsening air quality and an aging population, this clinical trial will evaluate a novel, multifaceted indoor air quality intervention to improve cardiovascular health outcomes among older adults in the wildfire-impacted state of Montana.

Study Overview

• Status: Not yet recruiting
• Conditions: Cardiovascular Diseases; Blood Pressure; Health Behavior; Cholesterol, LDL; Cholesterol, HDL; Cholesterol; Indoor Air Quality; Particulate Matter; Glycated Hemoglobin (HbA1c)
• Intervention / Treatment: Behavioral: Air Improvement and Real-time Monitoring for Wellness through Interactive Strategies and Education (AIRWISE); Other: Portable Air Cleaner (PAC) Control

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Estimated): 154
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ethan S Walker, PhD; Phone Number: 406-243-2063; Email: ethan.walker@umontana.edu

Study Locations

• United States
  • Montana
    • Missoula, Montana, United States, 59812
      • University of Montana
      • Contact: Ethan S Walker, PhD; Phone Number: 406-243-2063; Email: ethan.walker@umontana.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 55-79 years of age one primary residence (5+ days per week)
• have an electronic device, email address, and reliable internet at home for survey submission

Exclusion Criteria:

• current smoking of any kind or living in a household with someone who currently smokes
• current use of a portable air cleaner unit at home
• plans to move in the next year
• previous physician-diagnosed cardiovascular disease (coronary heart disease [myocardial infarction], stroke, or heart failure)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: AIRWISE Intervention; Participants randomized to the AIRWISE Intervention group will use AIRWISE in their homes for 12 months. The AIRWISE group will use two PACs to filter indoor air and two optical PM2.5 sensors with lights that change color in real time according to AQI. In addition, automated outdoor air quality alerts are sent via text and email when outdoor AQI goes above 75 (mid-point of the Moderate AQI category). Outdoor air quality will be referenced from the Environmental Protection Agency or PurpleAir monitor nearest to the participant's home. Based on the indoor and outdoor AQI levels, participants will reference a decision matrix and educational materials to make informed decisions on improving indoor air quality. Education and behavioral strategies are delivered through multiple approaches, including visual aids, handouts, videos, and a magnet with the decision matrix that can be placed in an accessible location in the home.	Behavioral: Air Improvement and Real-time Monitoring for Wellness through Interactive Strategies and Education (AIRWISE); The AIRWISE intervention consists of a 3-pronged approach grounded in the Health Belief Model (HBM) to improve residential indoor air quality through education, equipment, and behavioral cues. To reinforce cues to action, AIRWISE uses alerts from air quality sensors, prompting timely behavioral responses. Specifically, indoor and outdoor air quality alerts act as behavioral cues to promote active engagement and reference a decision matrix with specific recommendations based indoor and outdoor air quality. Recommendations on the decision matrix include simple strategies to reduce air pollution exposures, including increasing use and fan speed of portable air cleaners, opening or closing windows to change ventilation, and changing activities such as physical activity, cooking, and cleaning. This integrated approach promotes sustained behavior change by aligning with all key HBM constructs.
Active Comparator: PAC Control; Participants randomized to the PAC Control group will use two PACs in their home without additional AIRWISE equipment/education. After randomization, they will be given instructions on study procedures and using the PAC units according to manufacturer recommendations. PAC Control group participants will not receive further education on air quality or recommendations on PAC use, nor will they receive additional equipment or outdoor AQI alerts. They will receive PurpleAir sensors without an AQI light that are for data collection purposes only, and they will not have access to the data throughout the study. Control participants will use and maintain the PACs at their own discretion. At the end of their participation, they will have the option of receiving the additional AIRWISE components.	Other: Portable Air Cleaner (PAC) Control; Participants will use two PACs in their home according to manufacturer recommendations. PAC Control group participants will not receive further education on air quality or recommendations on PAC use, nor will they receive additional equipment or outdoor AQI alerts. Control participants will use and maintain the PACs at their own discretion.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Predicting Risk of CVD EVENTs (PREVENT) Score	Validated cardiovascular disease (CVD) risk score called Predicting Risk of CVD EVENTs (PREVENT). The score is a percentage ranging from 0 to 100 that indicates percentage risk of developing CVD, with higher scores indicating higher risk of developing CVD.	0, 6, 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Life's Essential 8 (LE8) Score	Validated metric of cardiovascular health called Life's Essential 8 (LE8). The score ranges from 0 to 100, with higher scores indicating better cardiovascular health and lower risk of adverse cardiovascular outcomes.	0, 6, 12 months
Indoor PM2.5	Fine particulate matter (PM2.5), or particles that are less than 2.5 micrometers in aerodynamic diameter and a primary component of air pollution	Continuous at 2-minute intervals
Indoor VOCs	Volatile Organic Compounds (VOCs), a component of air pollution	Continuous at 2-minute intervals
Glycated hemoglobin	A measure of blood sugar levels measured through venous blood draw and used to calculate the primary PREVENT outcome	0, 6, 12 months
Estimated Glomerular Filtration Rate	A measure of kidney function measured through venous blood draw and used to calculate the primary PREVENT outcome	0, 6, 12 months
Total cholesterol	Measured through venous blood draw and used to calculate the primary PREVENT outcome	0, 6, 12 months
HDL cholesterol	High-density lipoprotein cholesterol measured through venous blood draw and used to calculate the primary PREVENT outcome	0, 6, 12 months
LDL cholesterol	Low-density lipoprotein cholesterol measured through venous blood draw and used to calculate the primary PREVENT outcome	0, 6, 12 months
CRP	C-reactive protein, a measure of inflammation measured through venous blood draw	0, 6, 12 months
ESR	Erythrocyte sedimentation rate, used as a measure of inflammation measured through venous blood draw	0, 6, 12 months
Uric acid	Used as a measure of inflammation measured through venous blood draw	0, 6, 12 months
CBC	Used as a measure of inflammation measured through venous blood draw	0, 6, 12 months
Systolic and diastolic blood pressure	A risk factor for CVD and used to calculate the primary PREVENT outcome	Measured at baseline, followed by once per month through study completion, for a total of 13 measurements.
Health symptoms	Health symptoms will be reported in a questionnaire and used as a measure of quality of life. The questionnaire includes 6 questions and asks about recent illness and frequency of symptoms including eye irritation, blurred vision, wheezing, cough, throat irritation, difficulty breathing, excessive mucus, nose irritation, and headache.	Measured at baseline, followed by once per month through study completion, for a total of 13 measurements.
Physical activity	A risk factor for cardiovascular health and used to calculate the secondary LE8 outcome. Physical activity will be reported in a questionnaire. The questionnaire includes 12 questions and asks about type, duration, and location of recent physical activities.	Measured at baseline, followed by once per month through study completion, for a total of 13 measurements.
Sleep quality	A risk factor for cardiovascular health and used to calculate the secondary LE8 outcome. Sleep quality will be reported in a questionnaire. The questionnaire includes 9 questions and asks about duration, quality, barriers, and facilitators of sleep over the previous month.	Measured at baseline, followed by once per month through study completion, for a total of 13 measurements.
Diet	A risk factor for cardiovascular health and used to calculate the secondary LE8 outcome. Diet will be reported in a questionnaire. The questionnaire includes 16 questions and asks about the recent frequency and amount of consuming 16 different types of foods.	Measured at baseline, followed by once per month through study completion, for a total of 13 measurements.
BMI	A risk factor for cardiovascular health and used to calculate the secondary LE8 outcome	Baseline

Collaborators and Investigators

• Sponsor: University of Montana

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): July 1, 2030
• Study Completion (Estimated): July 1, 2030

Study Registration Dates

• First Submitted: April 6, 2026
• First Submitted That Met QC Criteria: April 13, 2026
• First Posted (Actual): April 20, 2026

Study Record Updates

• Last Update Posted (Actual): April 20, 2026
• Last Update Submitted That Met QC Criteria: April 13, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Behavior; Cardiovascular Diseases; Health Behavior; Socioeconomic Factors; Population Characteristics; Genetic Structures; Genetic Phenomena; Chromosomes, Artificial; Chromosomes; Genetic Vectors; Educational Status; Chromosomes, Artificial, P1 Bacteriophage
• Other Study ID Numbers: 25-0467

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No