Neurology: Beware of air pollution, the risk of dementia after exposure to PM2.5 increases significantly in old age

More and more evidences show that ambient air pollution is an environmental risk factor for brain aging.

In this way, Diana Younan and others of the University of Southern California, based on a community cohort of women (aged 70-89) and brain MRI scans, explored whether exposure to PM2.
5 in later life can lead to predicting Alzheimer's disease (AD) Progressive brain atrophy (progressive brain atrophy),

They used an AD pattern similarity (AD-PS) score, developed by supervised machine learning, and verified with the MRI data of the Alzheimer’s Disease Neuroimaging Initiative to capture brain areas that are susceptible to AD (such as Amygdala, hippocampus, parahippocampal gyrus, thalamus, inferior temporal lobe area and midbrain) atrophy of high-dimensional gray matter.

They also used the participant’s address and air monitoring data to estimate the average level of PM2.

They found that for 1,365 women 77.
9±3.
7 years old from 2005 to 2006, there was no correlation between PM2.
5 and baseline AD-PS scores in a cross-sectional analysis.

Longitudinal, during the follow-up period, every quartile increase in PM2.
5 (2.
82 micrograms/m3) was associated with an increase in AD-PS score, which was equivalent to a 24% increase in AD risk within 5 years (n = 712, age 77.
4) ± 3.
5 years old) .
After adjusting for sociodemographics, intracranial volume, lifestyle, clinical characteristics, and white matter lesions, this association still exists and is lower than the US regulatory standard (<12 µg/m3).

The important significance of this study is that exposure to PM2.
5 in later life is associated with an increased risk of AD neuroanatomical lesions, which may not be explained by indicators of cerebrovascular damage.

Original source:

neurology.