Effects of PM2.5 Reduction Interventions on Cardiovascular Indicators: A Meta-analysis.

Exposure to fine particulate matter (PM2.5) is associated with adverse cardiovascular outcomes, but the effectiveness of individual-level interventions to reduce exposure remains unclear. This meta-analysis aimed to assess the effects of four distinct categories of PM2.5 interventions on cardiovascular health including high-efficiency particulate air (HEPA) filters, respiratory protective equipment, improved cookstoves, and other behavioral PM2.5 reduction methods. We systematically searched PubMed, Embase, Web of Science, and the Cochrane library for studies published between December 2002 and March 2025 that reported the cardiovascular effect of PM2.5 reduction. Intervention methods were categorized based on their mechanisms of action and implementation settings. The primary outcomes were systolic blood pressure (SBP) and diastolic blood pressure (DBP), with secondary outcomes including endothelial function indices, heart rate variability (HRV), and inflammatory markers. A total of 72 trials involving 6,063 participants (age range: 12.4-82 years) were included. Overall, PM2.5 reduction interventions significantly decreased SBP by 1.97 mmHg (95% CI: -2.89, -1.05) and DBP by 1.08 mmHg (95% CI: -1.80, -0.35). Among secondary outcomes, C-reactive protein (CRP) decreased significantly (MD = -0.03mg/dl, 95% CI: -0.06, -0.00, P = 0.042), while no significant changes were observed in interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), or HRV. Subgroup analyses revealed differential effects by intervention type: Air filtration interventions showed the largest effect on SBP (MD = -1.94mmHg, 95% CI: -3.33, -0.55, P = 0.006) compared to other interventions. These findings suggest that PM2.5 reduction interventions could lower blood pressure and reduce markers of systemic inflammation, indicating that personal-level interventions may provide measurable cardiovascular benefits, even with short-term implementation.