Meta-Analysis of Association between Particulate Matter and Stroke Attack

Aims: We conducted systematic review as well as meta-analyses on the association between particulate matter and daily stroke attack from a number of epidemiologic studies. Methods: Twelve quantitative studies about the associations between particulate matter and stroke attack met the inclusive criteria. We evaluated the odds ratio (OR) of stroke attack associated with per 10 mu g/m3 increase of the concentration of PM10 (particulate matter with aerodynamic diameter = 10 mu m) or PM2.5 (particulate matter with aerodynamic diameter = 2.5 mu m) as effect scale, and a sensitivity analysis for the results was conducted. Results: In the time-series design, PM10 exposure wasn't related to an increased risk of daily stroke attack[OR per 10 mu g/m3= 1.002, 95% confidence interval (CI): 0.999.005], PM2.5 exposure were related to an increased risk of daily stroke attack (OR per 10 mu g/m3= 1.006, 95%CI: 1.0021.010]; but in the case-crossover studies, PM10 exposure was related to increase in risk of daily stroke attack (OR per 10 mu g/m3= 1.028, 95%CI: 1.0011.057). PM2.5 exposure was not significant association with daily stroke attack (OR per 10 mu g/m3= 1.016, 95%CI: 0.9371.097). Sensitivity analysis showed that the results for PM10, PM2.5 and daily stroke attack were robust in the time-series design. Conclusions: We found some evidence for an effect of air pollutants on stroke attack risk.