Objective. To estimate the risk of dementia in association with exposure to air pollutants.
Methods. Six databases were searched. Cohort studies that reported the hazard ratio (HR) of dementia in association with exposure to air pollutants in adults \u3e 40y were included. For all meta-analyses, the random-effects model was used.
Results. A total of 16 and 13 studies were included in the systematic review and the meta-analysis, respectively. Risk of dementia increased by 4% per 1μg/m3 increase in fine particulate matter level (HR, 1.04; 95%CI, [1.02, 1.06]), which was statistically significant. The risk of dementia increased by 3% per 10μg/m3 increase in nitrogen oxides level (HR, 1.03; 95%CI, [0.98, 1.08]), and by 3% per 10μg/m3 increase in nitrogen dioxide level (HR, 1.03; 95%CI, [1.00, 1.07]); however, the associations were not statistically significant
Conclusion. This meta-analysis indicates a significant association between exposure to fine particulate matter and incidence of dementia
