The Lancet Planetary Health has published a systematic review and meta-analysis of studies examining the association between air pollution and incident dementia. This review was intended to summarize all previous reviews, identify specific gaps in data, and incorporate new primary research. It included data from 32 studies and a pooled population of over 26 million people, evaluating the effect of long-term exposure (defined as one or more years) to single outdoor air pollutants on a subseque...