Residential aircraft and road noise exposure, cognition, and Alzheimer’s dementia in a US cohort of older adults
Stephanie T. Grady, Ryan M. Andrews, Junenette L. Peters, Sara D. Adar, Jonathan I. Levy, Todd Beck, Klodian Dhana, Pankaja Desai, Bernd J. Haupt, Joel D. Kaufman, Adam A. Szpiro, Robert S. Wilson, Kumar B. Rajan, Jennifer WeuveBackground:
There is limited evidence of the associations between transportation noise and dementia risk. We examined associations of road and aircraft noise with cognitive function, cognitive decline, and Alzheimer’s dementia (AD) in a cohort of older adults.
Methods:
We set our study in the Chicago Health and Aging Project, a longitudinal cohort of community-dwelling older adults from four Chicago, Illinois, neighborhoods, followed from 1993 to 2012. Every 3 years, participants underwent in-home cognitive assessments (episodic memory, perceptual speed, global cognition). A stratified random sample underwent clinical evaluation for AD diagnosis. We estimated 5-year time-weighted day–night average sound levels before baseline for road and, in analyses, we considered exploratory because of a limited exposure range, aircraft noise. We fit covariate-adjusted linear mixed models to estimate associations with cognitive performance and decline, and a multiple logistic regression model weighted by the sampling design to estimate incident AD odds ratios.
Results:
Of the 10,681 participants, an interquartile range increment in road noise (8.5 dBA) corresponded to a 0.06-SD unit lower baseline global cognitive score (95% confidence interval: −0.08, −0.03); there were no differences in cognitive decline. In exploratory analyses limited by power, higher aircraft noise was associated with a higher baseline score yet a faster rate of cognitive decline. Among 2147 participants evaluated for dementia (460 cases), road noise was not noticeably associated with greater AD risk, as there was substantial uncertainty (odds ratio per interquartile range = 1.17 [95% confidence interval: 0.86, 1.59]).
Conclusion:
We observed mixed associations of transportation noise with cognitive functioning and dementia across noise sources. These findings underscore the need to better characterize noise sources relevant to the cognitive health of older adults.