Greenness modifies the association between ambient air pollution and cognitive function in Australian adolescents, but not in mid-life adults

Yichao Wang; Mallery Crowe; Luke D Knibbs; Matthew Fuller-Tyszkiewicz; Lærke Mygind; Jessica A Kerr; Melissa Wake; Craig A Olsson; Peter G Enticott; Rachel L Peters; Galina Daraganova; Suzanne Mavoa; Kate Lycett

doi:10.1016/j.envpol.2023.121329

Greenness modifies the association between ambient air pollution and cognitive function in Australian adolescents, but not in mid-life adults

Environ Pollut. 2023 May 1:324:121329. doi: 10.1016/j.envpol.2023.121329. Epub 2023 Feb 21.

Authors

Affiliations

¹ Centre for Social and Early Emotional Development, School of Psychology, Deakin University, Geelong, VIC, 3220, Australia; Department of Paediatrics, University of Melbourne, Parkville, VIC, 3010, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia. Electronic address: yichao.wang1@deakin.edu.au.
² Centre for Social and Early Emotional Development, School of Psychology, Deakin University, Geelong, VIC, 3220, Australia.
³ School of Public Health, University of Sydney, Sydney, NSW, 2006, Australia; Public Health Unit, Sydney Local Health District, Camperdown, NSW, 2050, Australia.
⁴ Cognitive Neuroscience Unit, School of Psychology, Deakin University, Burwood, VIC, 3125, Australia; Unit of Medical Psychology, University of Copenhagen, Copenhagen, 1353, Denmark; Center for Clinical Research and Prevention, Copenhagen University Hospital - Bispebjerg and Frederiksberg, The Capital Region of Denmark, Copenhagen, 2000, Denmark.
⁵ Department of Paediatrics, University of Melbourne, Parkville, VIC, 3010, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia; Department of Psychological Medicine, University of Otago Christchurch, New Zealand.
⁶ Department of Paediatrics, University of Melbourne, Parkville, VIC, 3010, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia; Liggins Institute, University of Auckland, New Zealand.
⁷ Centre for Social and Early Emotional Development, School of Psychology, Deakin University, Geelong, VIC, 3220, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia; Psychological Sciences, University of Melbourne, Parkville, VIC, 3010, Australia.
⁸ Cognitive Neuroscience Unit, School of Psychology, Deakin University, Burwood, VIC, 3125, Australia.
⁹ Department of Paediatrics, University of Melbourne, Parkville, VIC, 3010, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia.
¹⁰ Psychological Sciences, University of Melbourne, Parkville, VIC, 3010, Australia; Business Intelligence, South Eastern Melbourne Primary Health Network, Melbourne, VIC, 3202, Australia.
¹¹ Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia; Environmental Public Health Branch, Environment Protection Authority Victoria, Melbourne, VIC, 3001, Australia; Melbourne School of Population and Global Health, University of Melbourne, Parkville, VIC, 3010, Australia.
¹² Centre for Social and Early Emotional Development, School of Psychology, Deakin University, Geelong, VIC, 3220, Australia; Population Health Theme, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia.

PMID: 36822308
DOI: 10.1016/j.envpol.2023.121329

Abstract

Exposure to ambient air pollution has been associated with reduced cognitive function in childhood and later life, with too few mid-life studies to draw conclusions. In contrast, residential greenness has been associated with enhanced cognitive function throughout the lifecourse. Here we examine the extent to which (1) ambient air pollution and residential greenness predict later cognitive function in adolescence and mid-life, and (2) greenness modifies air pollution-cognitive function associations.

Participants: 6220 adolescents (51% male) and 2623 mid-life adults (96% mothers) from the Longitudinal Study of Australian Children.

Measures: Exposures: Annual average particulate matter <2.5 μm (PM_2.5), nitrogen dioxide (NO₂) and greenness (Normalised Difference Vegetation Index) for residential addresses from validated land-use regression models over a 10-13-year period.

Outcomes: Cognitive function from CogState tests of attention, working memory and executive function, dichotomised into poorer (worst quartile) versus not poor.

Analyses: Adjusted mixed-effects generalised linear models with residential greenness assessed as an effect modifier (high vs. low divided at median). The annual mean for PM_2.5 and NO₂ across exposure windows was 6.3-6.8 μg/m³, and 5.5-7.1 ppb, respectively. For adolescents, an IQR increment of NO₂ was associated with 19-24% increased odds of having poorer executive function across all time windows, while associations weren't observed between air pollution and other outcomes. For adults, high NO₂ predicted poorer cognitive function across all outcomes, while high PM_2.5 predicted poorer attention only. There was little evidence of associations between greenness and cognitive function in adjusted models for both generations. Interactions were found between residential greenness, air pollutants and cognitive function in adolescents, but not adults. The magnitude of effects was similar across generations and exposure windows. Findings highlight the potential benefits of cognitive health associated with the regulation of air pollution and urban planning strategies for increasing green spaces and vegetation.

Keywords: Adolescence; Air pollution; Cognitive function; Greenness; Longitudinal; Mid-life.

MeSH terms

Adolescent
Air Pollutants* / adverse effects
Air Pollutants* / analysis
Air Pollution* / adverse effects
Air Pollution* / analysis
Australia / epidemiology
Child
Cognition
Environmental Exposure / adverse effects
Environmental Exposure / analysis
Female
Humans
Longitudinal Studies
Male
Nitrogen Dioxide / analysis
Particulate Matter / analysis

Substances

Nitrogen Dioxide
Air Pollutants
Particulate Matter