Understanding Critical Windows of Exposure in Longitudinal Analysis of Air Pollution and Cognitive Function

Background: Current research suggests adverse health effects of exposure to PM2.5 on cognitive decline and dementia-related outcomes. However, the critical windows of exposure related to exposure to air pollution remain unclear. This research aims to investigate these critical windows to better address the knowledge gap. Methods: We evaluated various longitudinal relationships between air pollution exposures and cognitive decline using cognitive measures in the ARIC cohort. Specifically, we evaluated the immediate effects of air pollution exposures over one year prior to each cognitive assessment using a time-varying effect model (TVEM), potential long-lasting health effects of air pollution exposure over one year prior to Visit 2 on all subsequent cognitive assessments using structural equation models (SEM), and cumulative and combined health effects of air pollution exposures including criteria air pollutants, components of PM2.5, and airborne trace metals in all defined time intervals on cognitive function using generalized linear mixed models (GLMM). Results: Air pollution exposures including PM2.5 over one year prior to each cognitive assessment have immediate deteriorating effects on subsequent cognitive measures of Digital Symbol Substitution (DSS) (estimate = -0.13, 95% CI = [-0.10, -0.02]) and Word Fluency Test (WFT)(estimate = -0.07, 95% CI = [-0.06, -0.09]). Similarly, air pollution exposures also have significant direct negative effects on the subsequent Delayed Word Recall (DWR), DSS, and WFT measurements (p-value < 0.001). Lastly, cumulative exposure to airborne trace metals negatively impacts cognitive measures including global cognition factor, executive function, language, and memory. Conclusions and Discussions: The findings of this research can help to define the underlying mechanisms of exposure windows and develop effective interventions to mitigate the adverse health effects of environmental exposures.

Name thesis:degree_name

Doctor of Public Health

Discipline thesis:degree_discipline

Public Health Sciences

Grantor

Texas A&M University

Year dc:date.issued

2025

Author dc:creator

• Fang, Vixey

Advisor dc:contributor.advisor

• Xu, Xiaohui

Committee members dc:contributor.committeemember

• Ni, Yang
• Gorman, Dennis
• Zheng, Qi

• Environmental Sciences
• Health Sciences, Epidemiology

Language dc:language.iso

English

Handle dc:identifier.uri

https://hdl.handle.net/1969.1/1600028

OAI record oai:identifier

https://oaktrust.library.tamu.edu/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Aoaktrust.library.tamu.edu%3A1969.1%2F1600028