Effect of portable air filtration systems on personal exposure to fine particulate matter and blood pressure among residents in a low-income senior facility: A randomized clinical trial

JAMA Internal Medicine Sep 14, 2018

Morishita M, et al. - In this randomized, double-blind, crossover intervention study, researchers examined the effectiveness of air filtration at reducing personal exposures to fine particulate matter smaller than 2.5 μm (PM2.5) and attenuating related cardiovascular (CV) health effects among older adults in a typical urban US location (Detroit, Michigan). Findings showed that, among older adults living in a typical US urban location, short-term use of portable air filtration systems reduced personal PM2.5 exposures and systolic blood pressure (BP) levels. For reducing PM2.5-related health effects, this relatively inexpensive and practical approach may be an effective tool.


  • This investigation was conducted from October 21, 2014, to November 4, 2016, in a low-income senior residential building in Detroit, Michigan.
  • A total of 40 nonsmoking older adults were enrolled, with daily CV health outcome and PM2.5 exposure measurements.
  • Study participants were exposed to the following three 3-day scenarios separated by 1-week washout periods: unfiltered air (sham filtration), low-efficiency (LE) high-efficiency particulate arrestance (HEPA)–type filtered air, and high-efficiency (HE) true-HEPA filtered air using filtration systems in their bedroom and living room.
  • Brachial BP was the primary outcome.
  • Aortic hemodynamics, pulse-wave velocity, and heart rate variability were the secondary outcomes.
  • Researchers measured exposures to PM2.5 in the participants’ residences and by personal monitoring.


  • According to the findings obtained, the 40 participants had a mean (standard deviation [SD]) age of 67 (8) years and 62% were men.
  • It was observed that personal PM2.5 exposures were significantly reduced by air filtration from a mean (SD) of 15.5 (10.9) μg/m3 with sham filtration to 10.9 (7.4) μg/m3 with LE filtration and 7.4 (3.3) μg/m3 with HE filtration.
  • Any filtration for 3 days decreased brachial systolic and diastolic BP levels by 3.2 mm Hg (95% confidence interval [CI]: -6.1 to -0.2 mm Hg) and 1.5 mm Hg (95% CI: -3.3 to 0.2 mm Hg), respectively, compared with sham filtration.
  • The data presented in this work showed that a continuous decrease occurred in systolic and diastolic BP levels during the 3-day period of LE filtration, with a mean of 3.4 mm Hg (95% CI: -6.8 to -0.1 mm Hg) and 2.2 mm Hg (95% CI: -4.2 to -0.3 mm Hg), respectively.
  • Systolic and diastolic BP levels decreased by 2.9 mm Hg (95% CI: -6.2 to 0.5 mm Hg) and 0.8 mm Hg (95% CI: -2.8 to 1.2 mm Hg), respectively, for HE filtration.
  • It was noted that most secondary outcomes were not significantly improved.
Go to Original

Sign-up to continue reading. It is free & takes less than 2 mins

  • 45 lakhs+ doctors trust M3 globally

  • Nonloggedininfinity icon
    Free & unlimited access to original articles and quizzes
  • Nonloggedinlock icon
    Secure: we never sell your data
This article is only available to members. Are you a doctor? Click here to signup for free.
M3 app logo
Choose easy access to M3 India from your mobile!

M3 instruc arrow
Add M3 India to your Home screen
Tap  Chrome menu  and select "Add to Home screen" to pin the M3 India App to your Home screen