Living in locations with greater improvements in air quality in late life was associated with slower rates of cognitive decline, reveals a recent study by researchers led by Dr Diana Younan, former Senior Research Associate at USC Keck School of Medicine, Los Angeles. The study, published in PLOS Medicine, focused on women aged 74 to 92 years and observed that the reduction in cognitive decline was equivalent to 1 or 1.5 years younger. It estimated the participant’s exposure to nitrogen dioxide and fine particulate matter or PM2.5 and found a reduction in nitrogen dioxide and PM2.5 levels in the 10-year period before enrollment in the study.