Long-term air pollution exposure and incident dementia: a systematic review and meta-analysis
Clare B Best Rogowski, Christiaan Bredell, Yan Shi, Alexandra Tien-Smith, Magdalena Szybka, Kwan Wai Fung, Lucy Hong, Veronica Phillips, Zorana Jovanovic Andersen, Stephen J. Sharp, James Woodcock, Carol Brayne, Annalan M D Navaratnam, Haneen Khreis
Abstract
BACKGROUND: A rapidly evolving evidence base suggests that exposure to outdoor air pollution is a risk factor for the onset of dementia, with an upturn in publications since 2022. We sought to synthesise and critically assess this evidence base accounting for the latest studies. METHODS: statistic and the Cochran Q test. Study-level risk of bias and confidence in the overall body of evidence were assessed with the Office of Health Assessment and Translation tool, and publication bias was examined. The protocol for this review was registered with PROSPERO, CRD42023414413. FINDINGS: =69%), with moderate to considerable heterogeneity between studies in these pooled analyses. Of the 32 studies overall, three (9%) had a probably high risk of bias in one of seven domains; all other studies had ratings of probably to definitely low risk of bias. The overall certainty of evidence of studies in the systematic review was moderate. INTERPRETATION: This analysis adds to the body of evidence that outdoor air pollutants are risk factors for dementia, indicating that reduced exposure to pollution could reduce dementia rates and stricter air quality standards would likely provide substantial health, social, and economic benefits. FUNDING: European Research Council under the Horizon 2020 research and innovation programme and the EU's Horizon Europe Framework Programme.