Long-term ambient PM2.5 and O3 reduced cognitive function in young adults as measured through the Lumosity brain training platform

Abstract

BACKGROUND AND AIM: A growing body of evidence indicates that exposure to air pollution affects cognitive performance; however, few studies have assessed this in the context of repeated measures within a large group of individuals. To evaluate the association between long-term exposure to ambient air pollution and aspects of cognitive function we used cognitive performance data from the mobile Lumosity brain training platform. METHODS: The study cohort included 29,091 Lumosity users in the contiguous US who completed 20 repetitions of the Lost in Migration game between 2017 and 2018. Game scores reflect focus and ability to filter information and avoid distracting information. Air pollution data included ambient PM2.5 and O3 averaged for the 365-day period before each gameplay date. Air pollution data from Federal Reference Method monitors was aggregated to the ZIP code (three-digit) level to match the geography included in the game data set. Generalized linear models were used to examine the association between long-term ambient PM2.5 and O3 and game score. Co-pollutant models were adjusted for meteorology, time trend, age, gender, device, education, local socioeconomic factors, and urbanicity. RESULTS:A 5 μg/m3 increase in PM2.5 was associated with lower user focus scores (-0.50% 95% CI: -0.80, -0.15). No association was observed with O3. Associations with scores were stronger among young adults (18-29 years old) for both PM2.5 (-1.25%; 95% CI: -2.25, -0.25) and O3 (-2.93% per 0.01 ppm; 95% CI: -4.64, -1.20). In the oldest age group (60-90 years old), PM2.5 was associated with decreased scores (-0.33%; 95% CI: -0.75, 0.09) and O3 associated with increased scores (1.22%; 95% CI: 0.54, 1.88). CONCLUSIONS:We observed that elevated long-term PM2.5 and O3 were associated with decreased focus score in young adults. This abstract does not reflect EPA policy. KEYWORDS: Air pollution, Particulate matter, Long-term exposure