title: Cognitive impacts of ambient air pollution in the National Social Health and Aging Project (NSHAP) cohort.
abstract: Pathways through which air pollution may impact cognitive function are poorly understood, particularly with regard to whether and how air pollution interacts with social and emotional factors to influence cognitive health.
  
  
  
  To examine the association between air pollutant exposures and cognitive outcomes among older adults participating in the National Social Life, Health, and Aging Project (NSHAP) cohort study.
  
  
  
  Measures of cognitive function, social connectedness, and physical and mental health were obtained for each NSHAP participant starting with Wave 1 of the study in 2005. Cognitive function was assessed using the Chicago Cognitive Function Measure (CCFM) for 3377 participants. Exposures to fine particles (PM2.5) were estimated for each participant using GIS-based spatio-temporal models, and exposures to nitrogen dioxide (NO2) were obtained from the nearest EPA monitors.
  
  
  
  In adjusted linear regression models, IQR increases in 1 to 7year PM2.5exposures were associated with a 0.22 (95% CI: -0.44, -0.01) to a 0.25 (95% CI: -0.43, -0.06) point decrease in CCFM scores, equivalent to aging 1.6years, while exposures to NO2were equivalent to aging 1.9years. The impacts of PM2.5on cognition were modified by stroke, anxiety, and stress, and were mediated by depression. The impacts of NO2were mediated by stress and effect modification by impaired activities of daily living for NO2was found.
  
  
  
  Exposures to long-term PM2.5and NO2were associated with decreased cognitive function in our cohort of older Americans, and individuals who experienced a stroke or elevated anxiety were more susceptible to the effects of PM2.5on cognition. Additionally, mediation results suggest that PM2.5may impact cognition through pathways related to mood disorders.
authors.affiliation: Department of Health Sciences,360 Huntington Avenue, Northeastern University, Boston, MA 02115, USA; MCPHS University, 179 Longwood Avenue, Boston, MA 02115, USA. Electronic address: tallon.l@husky.neu.edu.
authors.forename: Lindsay A
authors.initials: LA
authors.lastname: Tallon
authors.affiliation: Department of Health Sciences,360 Huntington Avenue, Northeastern University, Boston, MA 02115, USA. Electronic address: J.Manjourides@neu.edu.
authors.forename: Justin
authors.initials: J
authors.lastname: Manjourides
authors.affiliation: Department of Health Sciences,360 Huntington Avenue, Northeastern University, Boston, MA 02115, USA. Electronic address: C.Pun@neu.edu.
authors.forename: Vivian C
authors.initials: VC
authors.lastname: Pun
authors.affiliation: Department of Health Sciences,360 Huntington Avenue, Northeastern University, Boston, MA 02115, USA. Electronic address: C.Salhi@neu.edu.
authors.forename: Carmel
authors.initials: C
authors.lastname: Salhi
authors.affiliation: Department of Civil and Environmental Engineering, Tufts University, Medford, MA 02155, USA. Electronic address: helen.suh@tufts.edu.
authors.forename: Helen
authors.initials: H
authors.lastname: Suh
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000032:analysis*; D001007:Anxiety / Q000453:epidemiology; D003071:Cognition; D015331:Cohort Studies; D003863:Depression / Q000453:epidemiology; D005260:Female; D006304:Health Status; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009585:Nitrogen Dioxide / Q000032:analysis*; D052638:Particulate Matter / Q000032:analysis*; D012944:Social Support; D013315:Stress, Psychological / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D009585:Nitrogen Dioxide
keywords: Air pollution; Cognitive function; Epidemiology; Mental health; Older adults