Indoor Air Quality and Respiratory Symptoms in Former Smokers

Assessing the Effect of Different Efficiency Indoor Air Filters on Respiratory Symptoms in Former Smokers

The investigators will conduct a randomized, controlled, double-blind, crossover trial to determine whether the presence of a portable high-efficiency indoor air filter in the bedroom reduces respiratory symptoms in former smokers compared with placebo. The primary outcomes will be change in St. George's Respiratory Questionnaire - COPD (SGRQ-C) score associated with using a portable high-efficiency indoor air filter during the study period. Secondary outcomes of COPD exacerbations and hospitalizations, daily step counts, medication changes, spirometry, and cardiovascular outcomes will also be assessed.

Study Overview

• Status: Completed
• Conditions: Chronic Obstructive Pulmonary Disease
• Intervention / Treatment: Other: HEPA portable air filter; Other: Sham Control/Active Comparator

Detailed Description

Hypothesis/Research Questions:

This study will determine whether the presence of a portable high-efficiency indoor air filter in the bedroom improves respiratory symptoms (based on St. George's Respiratory Questionnaire - COPD - SGRQ-C score) during a period of high air pollution compared with placebo in former smokers with respiratory symptoms.

The primary outcome will be the change in SGRQ-C score associated with using a portable high-efficiency indoor air filter during the study period.

Secondary outcomes will assess the effect of using a portable high-efficiency indoor air filter on healthcare utilization, other symptom scores, COPD exacerbation frequency, medication use, median daily step counts, inflammatory markers, oxygenation, indoor particulate counts and indoor-outdoor particulate count difference, and pulmonary function tests.

Baseline descriptive statistics will report baseline air filter type, duration of use, and particulate weight prior to study enrollment.

Evaluation of change in symptom scores and other secondary outcomes from baseline to study air filter (Visit 1 vs. Visit 2).

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

Contacts and Locations

Study Locations

• United States
  • Utah
    • Salt Lake City, Utah, United States, 84107
      • Intermountain Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• history of smoking
• Do not currently smoke and no one currently smokes inside the home
• history of exacerbation or development of respiratory symptoms (e.g.cough, sputum production, chest tightness, exertional dyspnea, etc.) with periods of high outdoor air pollution ("inversions")
• Age 40 or older
• Access to Wi-Fi
• Access to a cell phone, tablet or personal computer

Exclusion Criteria:

• active tobacco use of subject
• active tobacco use in the home
• pre-existing use of a HEPA filter in the subject's bedroom

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ARM 1 MERV17 first; This group will receive a portable HEPA air filtering device with MERV17 air filter for the first part of the study. At cross over, this group will receive the "placebo" or no high-efficiency filter.	Other: HEPA portable air filter; A high efficiency (MERV17) portable air filter (HEPA portable air filter) will be placed in the subject's bedroom and will run 24/7 for the duration of the study.
Active Comparator: ARM 2 MERV17 second; This group will receive a HEPA portable air filter with no high efficiency air filter for the first part of the study. At cross over, this group will receive the high-efficiency MERV17 air filter.	Other: Sham Control/Active Comparator; A portable air filtering device will be placed with no high-efficiency air filter, but only the basic carbon filter in place. Then at cross over, there will be an active HEPA portable air filter used

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in SGRQ-C score	based on St. George's Respiratory Questionnaire - COPD - SGRQ-C score	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of air filtration on healthcare utilization	Effect on COPD related ER visits and hospitalizations; CHF and MI related visits and hospitalizations and all cause ER visits and hospitalizations	6 months
Aggregated assessment of the effect of air filtration on COPD exacerbation frequency	A combined assessment of patient reported symptom questionnaires including increased medication use, ER visits and hospitalizations for breathing-related problems and COPD exacerbations. These assessments will be determined by patient reported hospitalizations/ED visits, and patient reported symptom increase and COPD-related medication changes.	6 months
Change in median daily step counts	Whether median daily step counts are affected by air pollution levels, or correlate with other metrics of COPD outcomes remains unknown and thus, step counts will be tracked.	6 months
Change in inflammatory markers	This is a common office test used to assess how well the lungs work by measuring how much air the patients inhale, how much they exhale, and how quickly they exhale. We will also perform pulse oximetry and a blood draw to assess inflammatory markers and basic labs. COPD sufferers experience inflammation due to their disease. Inflammatory markers will be documented during their clinic visits.	6 months
Change in spirometry	Spirometry will be used to assess how well a subject's lungs work by measuring how much air is inhaled, how much is exhaled and how quickly you exhale. Spirometry is used to diagnose COPD and tracks it's progression or improve.	3 months
Number of cardiovascular events	CVA, MI, heart failure exacerbation	6 months
Change in 6 minute walk test	The 6 Minute Walk Test is a sub-maximal exercise test used to assess aerobic capacity and endurance. The distance covered over a time of 6 minutes is used as the outcome by which to compare changes in performance capacity.	3 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in sleep efficiency	As measured by the activity tracker, the amount of hours slept	12 weeks
Change in sleep quality	As measured by the activity tracker, the number of disruptions in sleep	12 weeks
Change in CAT scores	COPD assessment test is a questionnaire used to determine subjective improve or progression of COPD.	12 weeks
Change in mMRC scores	Modified Medical Research Council Dyspnea Scale score used to track a subject's shortness of breath	12 weeks
Change in other metrics of activity: specifically 6min walk distances and max walk distance	walk distance	12 weeks
Change in air filter changing habits	Change in air filter changing habits	12 months
Change in air filter weight with different filters (surrogate for particulates trapped)	Change in air filter weight with different filters (surrogate for particulates trapped)	12 months
Change in activity tracker use following study	Question in 6 month follow up from study if participants bought their own step counter or if they already had a step counter, if they use the device more as a result of the study.	12 months
Change in indoor particulate concentration as measured by personal air monitors (PurpleAir.org)	Change in indoor particulate concentration as measured by personal air	3 months

Collaborators and Investigators

• Sponsor: Intermountain Health Care, Inc.
• Investigators: Principal Investigator: Denitza Blagev, MD, Intermountain Health Care, Inc.

Study record dates

Study Major Dates

• Study Start: November 1, 2016
• Primary Completion (Actual): May 15, 2019
• Study Completion (Actual): June 1, 2019

Study Registration Dates

• First Submitted: October 19, 2016
• First Submitted That Met QC Criteria: November 2, 2016
• First Posted (Estimate): November 6, 2016

Study Record Updates

• Last Update Posted (Actual): June 13, 2019
• Last Update Submitted That Met QC Criteria: June 12, 2019
• Last Verified: June 1, 2019

More Information

Terms related to this study

• Keywords: COPD; emphysema; chronic obstructive pulmonary disease; tobacco use; respiratory symptoms; indoor air quality; air filter
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive; Signs and Symptoms, Respiratory
• Other Study ID Numbers: 1050302

Plan for Individual participant data (IPD)

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