A long term study including over 63 million elder U.S. led by the researchers of Harvard T.H. Chan School of Public Health have suggested that air pollution significantly increased risk of hospital admissions for various neurological disorders such as Alzheimer's disease, Parkinson's disease, and other dementias. The study collaborated with the researchers of Columbia University's Mailman School of Public Health and Emory University's Rollins School of Public Health. This is the first long term nationwide study that focused on the link between neurodegenerative diseases and fine particulate (PM2.5) pollution in the U.S.
Xiao Wu, co-lead author from Harvard Chan School stated, “The 2020 report of the Lancet Commission on dementia prevention, intervention, and care has added air pollution as one of the modifiable risk factors for these outcomes. Our study builds on the small but emerging evidence base indicating that long-term PM2.5 exposures are linked to an increased risk of neurological health deterioration, even at PM2.5 concentrations well below the current national standards.”
In the study, researchers considered 17 years' hospital admissions data of over 63 million Medicare recipients in the U.S. and were associated with estimated PM2.5 concentrations by zip code. Moreover, researchers considered potential confounding factors such as socioeconomic status, and observed that for each 5 microgram per cubic meter of air (μg/m3) upsurge in annual PM2.5 concentrations, risk for first-time hospital admissions for Parkinson's disease and for Alzheimer's disease, related dementias increased by 13%.
Researchers also highlighted that urban populations, women, and white people, were vulnerable especially. Geriatric populace of northeastern U.S were at higher risk for first-time Parkinson's disease hospital admissions and older adults in the Midwest faced were at highest risk for first-time Alzheimer's disease and related dementias hospital admissions.