May 5, 2024

The Invisible Enemy: Ambient Air Pollution Elevates Dementia Risk

Senior author William S. Kremen, Ph.D., teacher of psychiatry and co-director of the Center for Behavior Genetics of Aging at UC San Diego School of Medicine, and coworkers examined standard cognitive evaluations of approximately 1,100 men taking part in the ongoing Vietnam Era Twin Study of Aging. The average standard age was 56, with 12 years of follow-up.
They furthermore looked at measures of direct exposure to particular matter (PM2.5) in the air and nitrogen dioxide (NO2), which is created when nonrenewable fuel sources are burned, and assessments of episodic memory, executive function, spoken fluency, brain processing speed, and APOE genotype.
APOE is a gene that offers instructions for making a protein crucial to the transportation of cholesterol and other fats in the blood stream. One version or allele of APOE called APOE-4 has actually been identified as a strong danger factor gene for Alzheimers disease.
The researchers found that participants with higher levels of direct exposure to PM2.5 and NO2 in their 50s and 40s displayed even worse cognitive functioning in spoken fluency from age 56 to 68. And persons with the APOE-4 allele appeared even more sensitive, with those exposed to greater PM2.5 levels revealing worse results for executive function and those with higher NO2 direct exposure revealing even worse results including episodic memory.
Executive function refers to higher-level cognitive skills used to plan, control and coordinate mental habits and acts. Episodic memory is the capability to remember and re-experience unique, specific previous events.
” The 2020 Lancet report concluded that customizing 12 threat elements, that include others like education and anxiety at midlife, could decrease dementia occurrence by as much as 40%,” stated first author Carol E. Franz, Ph.D., teacher of psychiatry and co-director of the Center for Behavior Genetics of Aging.
” That report put ambient air pollution as a greater danger for Alzheimers and associated dementias than diabetes, physical activity, hypertension, alcohol usage, and obesity. Our findings underscore the importance of recognizing modifiable danger elements as early in life as possible– which the procedures by which air pollution impacts risk for later-life cognitive decrease start earlier than previous studies suggest.”
Referral: “Associations Between Ambient Air Pollution and Cognitive Abilities from Midlife to Early Old Age: Modification by APOE Genotype” by Carol E Franz, Daniel E Gustavson, Jeremy A Elman, Christine Fennema-Notestine, Donald J Hagler Jr, Aaron Baraff, Xin M Tu, Tsung-Chin Wu, Jaden De Anda, Asad Beck, Joel D Kaufman, Nathan Whitsel, Caleb E Finch, Jiu-Chiuan Chen, Michael J Lyons and William S Kremen, 2 May 2023, Journal of Alzheimers Disease.DOI: 10.3233/ jad-221054.
The study was moneyed by the National Institute on Aging.

Exposure to ambient air pollution, such as automobile exhaust, has been connected to a higher threat of establishing dementia; genes can increase the risk. Credit: IQAir
Research study reveals a link between ecological air contamination and particular dementia qualities, like impaired spoken fluency. Possession of a particular gene version seems to amplify and complicate this risk.
An international study commissioned by the Lancet three years ago laid out 12 overall modifiable threats linked to dementia. It also recognized a trio of newly recognized factors adding to dementia risk, namely, excessive alcohol consumption, head injury, and air pollution.
A current research study released in the Journal of Alzheimers Disease, a research group spearheaded by researchers from the University of California San Diego, supplied further insights into the function of air contamination– particularly ambient pollution originating from sources such as vehicular exhaust and power plant emissions– in increasing the risk of dementia throughout time. The research study verified that exposure to this kind of contamination is related to a measurably greater threat of developing dementia in time.