The Association Between Ambient Air Pollution and Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia; it has been known to increase the risk of stroke and heart failure. The association between air pollutants and AF has remained to be controversial. Thus, in this study, we sought to undertake a systematic review and meta-analysis in order to assess the short- and long-term effects of ambient air pollution on AF.We searched PubMed, Web of Science, Embase, and Ovid for all related studies up to October 2019. We used the random-effects model to estimate the excess risk percentage (ER%) and confidence intervals (CI) for particulate matter with diameter ≤ 2.5 (PM_2.5) and ≤ 10 μm (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), ozone (O₃), and carbon monoxide (CO). Results were further analyzed by subgroups according to location, age, outcome, and gender.In total, 18 studies were included in our meta-analysis: 5 evaluated for long-term effects, 12 for short-term effects, and 1 for both long- and short-term effects. For the short term, ER per 10 μg/m³ increase of pollutants was 1.8% (0%-3.7%) for PM_2.5 and 1.1% (-0.2%-2.4%) for PM₁₀; per 10 parts per billion (ppb) increment of gaseous pollutions was 3.2% (0.6%-5.8%) for NO₂, 2.9% (0.3%-5.7%) for SO₂, 0.5% (-3.4%-4.7%) for O₃, and 2.0% (-1.3%-5.4%) for CO per 1000 ppb change. The subgroup analysis showed the short-term effect was significantly different by region, gender, outcome, and age. Meanwhile, in the long term, except for O₃, a statistically significant association was noted between AF incidence and all pollutants.Our meta-analysis suggests that short-term exposure to part of pollutants (PM_2.5, SO₂, and NO₂) increases AF attack. Further, long-term exposure to air pollution can significantly contribute to the incidence of AF in a healthy population.