NCT05718245 · University of Southern California
HEPA, PM2.5, and Cardiometabolic Health
What this study is about
The goal of this randomly assigned, where neither patients nor doctors know which treatment is given, crossover trial is to test the hypothesis that a longer-term indoor HEPA filtration intervention can improve cardiometabolic profiles by reducing indoor PM2.5 exposures in at-risk individuals.
View original scientific description
The goal of this randomized, double-blind, crossover trial is to test the hypothesis that a longer-term indoor HEPA filtration intervention can improve cardiometabolic profiles by reducing indoor PM2.5 exposures in at-risk individuals.
Interventions
DEVICE
HEPA filter
HEPA filters with the capacity to reduce PM2.5 levels
DEVICE
Sham filter
sham filters without the capacity to reduce PM2.5 levels
Primary outcome measures
Change in HOMA-IR
Time frame: At the baseline and immediately after each of the 6-month interventions
Difference between baseline and HOMA-IR measured after 6-month intervention
Change in HbA1c
Time frame: At the baseline and immediately after each of the 6-month interventions
Difference between baseline and HOMA-IR measured after 6-month intervention
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age between 65 and 84 years old;
- Nonsmoker for at least 1 year;
- History of BMI ≥ 25 kg/m2 in the past based on EMR information;
- Either an English or Spanish speaker;
- Live in the Los Angeles County.
Exclusion criteria
- History of diabetes (both type 1 and type 2) or degenerative disease of the nervous system (Alzheimer's disease or dementia);
- Currently have active cancer treatment;
- The residential house has already had HEPA filters;
- Participants will move out of the current house in the next 2 years;
- Participants will spend more than one month living outside the primary home;
- Have any health conditions that prohibit collecting health and covariate data and biospecimen;
- The residential houses are not feasible for setting up air purifiers and air pollutants monitors;
- Have high blood glucose from finger stick test (\> 200 mg/dL).
Where
- Los Angeles, California
Collaborators
Duke University
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 1, 2025 · Source of record for eligibility and locations