NCT05867381

Brief Summary

This double-blind, randomized, crossover trial aims to test the hypothesis that longer-term indoor air filtration intervention can slow atherothrombosis progression by reducing indoor fine particulate matter (PM2.5) exposure in adults with ischemic heart disease history.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
112

participants targeted

Target at P50-P75 for not_applicable

Timeline
14mo left

Started Jul 2023

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress71%
Jul 2023Jun 2027

First Submitted

Initial submission to the registry

April 23, 2023

Completed
29 days until next milestone

First Posted

Study publicly available on registry

May 22, 2023

Completed
2 months until next milestone

Study Start

First participant enrolled

July 11, 2023

Completed
4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 30, 2027

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 30, 2027

Last Updated

August 1, 2025

Status Verified

July 1, 2025

Enrollment Period

4 years

First QC Date

April 23, 2023

Last Update Submit

July 29, 2025

Conditions

Air PollutionAtherosclerosis

Keywords

Air pollutionParticulate matterAir purifierHEPA filterAtherosclerosisIschemic Heart DiseaseThrombosisCardiovascular Disease

Outcome Measures

Primary Outcomes (5)

  • Change in blood pressure

    Differences between baseline and systolic and diastolic blood pressure measured during and after intervention

    Blood pressure will be monitored daily during each of the 9-month intervention

  • Change in carotid-femoral pulse wave velocity

    Differences between baseline and carotid-femoral pulse wave velocity measured with Vicorder device during and after intervention

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in augmentation index

    Differences between baseline and augmentation index measured with Vicorder device during and after intervention

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in von Willebrand factor

    Differences between baseline and von Willebrand factor measured during and after intervention

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in P-selectin

    Differences between baseline and P-selectin measured during and after intervention

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

Secondary Outcomes (6)

  • Change in fasting glucose

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in fasting insulin

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Changes in lipid profiles

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in C-reactive protein

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • Change in interleukin 6

    At the baseline, in the middle (4.5 month after intervention) and immediately after each of the 9-month interventions

  • +1 more secondary outcomes

Study Arms (2)

HEPA first and sham

EXPERIMENTAL

This group of participants will be assigned to the intervention of HEPA filtration with the capacity to reduce indoor PM2.5 levels at their residence for 9 months first. After 3-month wash-out period, participants will be assigned to sham filters (air purifier has the same appearance but HEPA filter is removed) for 9 months.

Device: HEPA filtrationDevice: Sham filtration

Sham first and HEPA

EXPERIMENTAL

This group of participants will be assigned to the intervention of sham filtration with HEPA filter removed at their residence for 9 months first. After 3-month wash-out period, participants will be assigned to the HEPA filtration for 9 months.

Device: HEPA filtrationDevice: Sham filtration

Interventions

HEPA filtrationDEVICE

HEPA filters with the capacity to reduce PM2.5 levels

HEPA first and shamSham first and HEPA
Sham filtrationDEVICE

Sham filtration use the same appearance of air purifier but with HEPA filter removed.

HEPA first and shamSham first and HEPA

Eligibility Criteria

Age65 Years - 84 Years
Sexall
Healthy VolunteersNo
Age GroupsOlder Adult (65+)

You may qualify if:

  • Age between 65 and 84 years old;
  • Weight ≥ 110 pounds;
  • Nonsmokers for at least 1 year;
  • Have ischemic heart disease history, clinically stable for 6 months, without any deterioration in symptoms or episodes of angina based on past electronic medical records;
  • Both English and Spanish speaking participants will be included in the recruitment;
  • Live in the Los Angeles County.

You may not qualify if:

  • Have history of degenerative disease of the nervous system such as dementia and Alzheimer's;
  • Currently have active cancer treatments;
  • The residential house has already had HEPA filters;
  • Participants will move out from the current residential address in the next 2 years;
  • Participants will spend more than 1 month living outside the primary home;
  • Have any health conditions that prohibit collecting health and covariate data and biospecimens;
  • Participants' residential houses are not feasible for setting up air purifiers and air pollutants monitors.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Keck School of Medicine, University of Southern California

Los Angeles, California, 90033, United States

RECRUITING

MeSH Terms

Conditions

AtherosclerosisMyocardial IschemiaThrombosisCardiovascular Diseases

Condition Hierarchy (Ancestors)

ArteriosclerosisArterial Occlusive DiseasesVascular DiseasesHeart DiseasesEmbolism and Thrombosis

Study Officials

  • Zhanghua Chen, PhD

    University of Southern California

    PRINCIPAL INVESTIGATOR

  • Junfeng Zhang, PhD

    Duke University

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Zhanghua Chen, PhD

CONTACT

323-442-2109zhanghuc@usc.edu

Junfeng Zhang, PhD

CONTACT

919-681-7782junfeng.zhang@duke.edu

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Masking Details
A sham filter will be used in the control, to replace HEPA filter in the intervention group. Participants and investigators will be blinded to the intervention type, only investigators who will prepare air filters for intervention will be unblinded for the real air filter type.
Purpose
PREVENTION
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor

Study Record Dates

First Submitted

April 23, 2023

First Posted

May 22, 2023

Study Start

July 11, 2023

Primary Completion (Estimated)

June 30, 2027

Study Completion (Estimated)

June 30, 2027

Last Updated

August 1, 2025

Record last verified: 2025-07

Data Sharing

IPD Sharing
Will not share

Locations

US(1)