Abstract Air pollution, particularly fine particulate matter (PM 2.5 ), poses a significant global health risk, contributing to respiratory, and cardiovascular diseases. While personal-level interventions such as air purifiers and respirators are commonly used to reduce exposure, their effectiveness in improving clinical outcomes remains uncertain. This systematic review and meta-analysis evaluated the efficacy of such measures in reducing adverse respiratory and cardiovascular outcomes. A systematic search of PubMed, Embase, Scopus, and the Cochrane Library was conducted up to February 2025. Randomized controlled trials (RCTs) assessing the use of air purifiers or respirators in non-occupational settings were included. Meta-analyses were performed using fixed or random-effects models, and effect sizes were expressed as standardized mean differences (SMDs) with 95% confidence intervals (CIs). Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Twenty-seven RCTs were included. Personal-level interventions significantly reduced indoor PM 2.5 (SMD = −2.27; 95% CI: −2.98 to −1.55) and PM 10 (SMD = −3.87; 95% CI: −4.59 to −3.16) levels. However, no significant improvements were observed for forced expiratory volume in one second (FEV 1 ) (SMD = 0.04; 95% CI: −0.07 to 0.15), peak expiratory flow (PEF), forced vital capacity (FVC), respiratory symptoms, or blood pressure. Sensitivity analysis showed a significant reduction in FeNO (SMD = −0.16; 95% CI: −0.28 to −0.04). While effective in reducing particulate matter, personal-level interventions showed limited clinical benefits for respiratory or cardiovascular health.
Mudgal et al. (Fri,) studied this question.