HEPA, PM2.5, and Cardiometabolic Health

Using Indoor Air Filtration to Reduce PM2.5 Cardiometabolic Effects in At-risk Individuals

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.

Study Overview

• Status: Recruiting
• Conditions: Air Pollution; Cardiometabolic Health
• Intervention / Treatment: Device: HEPA filter; Device: Sham filter

Detailed Description

This randomized, double-blind, crossover trial will recruit 52 non-diabetic adults and will investigate potential benefits of HEPA air purifiers on improving cardiometabolic profiles. Participants will be contacted and recruited to the study based on inclusion and exclusion criteria. After consenting, participants will be block randomized to HEPA and control groups for 6-month interventions by sex. After 6-month wash-out period, participants will be switched to the other arm of the intervention. During the trial, project specialists will complete a series of home visits before and after each intervention session to set up air purifiers and indoor and outdoor air pollution monitors, as well as conduct interview to collect questionnaire data, measure body weight and blood pressure, and collect biospecimen. In aim 1, the researcher will assess the effect of a 6-month residential HEPA intervention on changes of type 2 diabetes-related metabolic outcomes in 52 adults. In aim 2, the researchers will examine the association between reduction in indoor PM2.5 exposure brought by the intervention and changes in metabolic outcomes adjusting for ambient PM2.5 exposure. In aim 3, the researchers will explore major pathophysiologic changes pertinent to the cardio-metabolic profile of type 2 diabetes relevance in response to the intervention and changes in PM2.5 exposure.

• Study Type: Interventional
• Enrollment (Estimated): 52
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Zhanghua Chen, PhD; Phone Number: 323-442-2109; Email: zhanghuc@usc.edu
• Study Contact Backup: Name: Junfeng Zhang, PhD; Phone Number: 919-681-7782; Email: junfeng.zhang@duke.edu

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90033
      • Recruiting
      • Keck School of Medicine, University of Southern California
      • Contact: Zhanghua Chen, PhD; Phone Number: 323-442-2109; Email: zhanghuc@usc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years to 84 years (Older Adult)
• Accepts Healthy Volunteers: Yes

Description

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).

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: HEPA first and sham; This group of participants will be assigned an intervention of HEPA filters with the capacity to reduce PM2.5 levels at their residence for 6 months. After 6-month wash-out period, will be assigned to sham filters for 6 months.	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
Sham Comparator: Sham first and HEPA; This group of participants will be assigned an intervention of sham filters without the capacity to reduce PM2.5 levels at their residence for 6 months. After 6-month wash-out period, will be assigned to HEPA filters for 6 months.	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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HOMA-IR	Difference between baseline and HOMA-IR measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions
Change in HbA1c	Difference between baseline and HOMA-IR measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in fasting glucose	Difference between baseline and fasting glucose measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions
Change in fasting insulin	Difference between baseline and fasting insulin measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions
Changes in lipid profiles	Differences between baseline and LDL, HDL, VLDL, triglycerides, and total cholesterol levels measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions
Change in blood pressure	Differences between baseline and systolic and diastolic blood pressure measured after 6-month intervention	At the baseline and immediately after each of the 6-month interventions
Change in continuously monitored glucose level	Difference in continuously measured glucose measured using Abbott FreeStyle Libre 2 Pro Continuous Glucose Monitor (CGM) for 2 weeks between baseline and after intervention.	At the baseline and immediately after 3 months of intervention

Collaborators and Investigators

• Sponsor: University of Southern California
• Collaborators: Duke University
• Investigators: Principal Investigator: Zhanghua Chen, PhD, University of Southern California; Principal Investigator: Junfeng Zhang, PhD, Duke University

Study record dates

Study Major Dates

• Study Start (Actual): March 15, 2023
• Primary Completion (Estimated): April 1, 2025
• Study Completion (Estimated): April 1, 2025

Study Registration Dates

• First Submitted: January 24, 2023
• First Submitted That Met QC Criteria: February 7, 2023
• First Posted (Actual): February 8, 2023

Study Record Updates

• Last Update Posted (Estimated): February 5, 2024
• Last Update Submitted That Met QC Criteria: February 1, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Air pollution; Particulate matter; Air purifier; HEPA filter; Cardiometabolic health
• Other Study ID Numbers: UL2_Study

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