• DOI:10.1212/WNL.0000000000011149
• Corpus ID: 227065262

PM2.5 Associated With Gray Matter Atrophy Reflecting Increased Alzheimer Risk in Older Women

@article{Younan2020PM25AW,
  title={PM2.5 Associated With Gray Matter Atrophy Reflecting Increased Alzheimer Risk in Older Women},
  author={Diana Younan and Xinhui Wang and Ramon Casanova and Ryan T. Barnard and Sarah A. Gaussoin and Santiago Saldana and Andrew J. Petkus and Daniel P. Beavers and Susan M. Resnick and JoAnn E. Manson and Marc L. Serre and William Vizuete and Victor W. Henderson and Bonnie C. Sachs and Joel Salinas and Margaret Gatz and Mark A. Espeland and Helena Chui and Sally A. Shumaker and Stephen R. Rapp and Jiu Chiuan Chen},
  journal={Neurology},
  year={2020},
  volume={96},
  pages={e1190 - e1201}
}

• D. Younan, Xinhui Wang, +18 authors J. Chen
• Published 18 November 2020
• Medicine, Psychology
• Neurology

Objective To examine whether late-life exposure to PM2.5 (particulate matter with aerodynamic diameters <2.5 µm) contributes to progressive brain atrophy predictive of Alzheimer disease (AD) using a community-dwelling cohort of women (age 70–89 years) with up to 2 brain MRI scans (MRI-1, 2005–2006; MRI-2, 2010–2011). Methods AD pattern similarity (AD-PS) scores, developed by supervised machine learning and validated with MRI data from the Alzheimer’s Disease Neuroimaging Initiative, were used to capture high-dimensional gray matter atrophy in brain areas vulnerable to AD (e.g., amygdala, hippocampus, parahippocampal gyrus, thalamus, inferior temporal lobe areas, and midbrain). Using participants' addresses and air monitoring data, we implemented a spatiotemporal model to estimate 3-year average exposure to PM2.5 preceding MRI-1. General linear models were used to examine the association between PM2.5 and AD-PS scores (baseline and 5-year standardized change), accounting for potential confounders and white matter lesion volumes. Results For 1,365 women 77.9 ± 3.7 years of age in 2005 to 2006, there was no association between PM2.5 and baseline AD-PS score in cross-sectional analyses (β = −0.004; 95% confidence interval [CI] −0.019 to 0.011). Longitudinally, each interquartile range increase of PM2.5 (2.82 µg/m3) was associated with increased AD-PS scores during the follow-up, equivalent to a 24% (hazard ratio 1.24, 95% CI 1.14–1.34) increase in AD risk over 5 years (n = 712, age 77.4 ± 3.5 years). This association remained after adjustment for sociodemographics, intracranial volume, lifestyle, clinical characteristics, and white matter lesions and was present with levels below US regulatory standards (<12 µg/m3). Conclusions Late-life exposure to PM2.5 is associated with increased neuroanatomic risk of AD, which may not be explained by available indicators of cerebrovascular damage.