Urban green space and the risks of dementia and stroke

Lauren A Paul; Perry Hystad; Richard T Burnett; Jeffrey C Kwong; Dan L Crouse; Aaron van Donkelaar; Karen Tu; Eric Lavigne; Ray Copes; Randall V Martin; Hong Chen

doi:10.1016/j.envres.2020.109520

Urban green space and the risks of dementia and stroke

Environ Res. 2020 Jul:186:109520. doi: 10.1016/j.envres.2020.109520. Epub 2020 Apr 17.

Authors

Lauren A Paul¹, Perry Hystad², Richard T Burnett³, Jeffrey C Kwong⁴, Dan L Crouse⁵, Aaron van Donkelaar⁶, Karen Tu⁷, Eric Lavigne⁸, Ray Copes⁹, Randall V Martin¹⁰, Hong Chen¹¹

Affiliations

¹ Department of Environmental and Occupational Health, Public Health Ontario, 480 University Ave. Suite 300, Toronto, ON, M5G 1V2, Canada. Electronic address: lauren.paul@oahpp.ca.
² College of Public Health and Human Sciences, Oregon State University, Women's Bldg, 160 SW 26th St., Corvallis, OR, 97331, USA. Electronic address: perry.hystad@oregonstate.edu.
³ Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, Finance Bldg, 101 Tunney's Pasture Drwy, Ottawa, ON, K1A 0K9, Canada. Electronic address: rick.burnett@canada.ca.
⁴ Public Health Ontario Laboratories, Public Health Ontario, 661 University Ave. Suite 1701, Toronto, ON, M5G 1M1, Canada; ICES, 2075 Bayview Ave. G1 06, Toronto, ON, M4N 3M5, Canada; Dalla Lana School of Public Health, University of Toronto, 155 College St. Room 500, Toronto, ON, M5T 3M7, Canada; Department of Family and Community Medicine, University of Toronto, 500 University Ave. 5th Floor, Toronto, ON, M5G 1V7, Canada. Electronic address: jeff.kwong@utoronto.ca.
⁵ Health Effects Institute, 75 Federal St. Suite 1400, Boston, MA, 02110-1817, USA. Electronic address: dcrouse@healtheffects.org.
⁶ Department of Physics and Atmospheric Science, Dalhousie University, Sir James Dunn Bldg, 6310 Coburg Rd., Halifax, NS, B3H 4J5, Canada. Electronic address: aaron.van.donkelaar@dal.ca.
⁷ Dalla Lana School of Public Health, University of Toronto, 155 College St. Room 500, Toronto, ON, M5T 3M7, Canada; Department of Family and Community Medicine, University of Toronto, 500 University Ave. 5th Floor, Toronto, ON, M5G 1V7, Canada. Electronic address: k.tu@utoronto.ca.
⁸ Air Health Science Division, Health Canada, 269 Laurier Ave. W A.L. 4903B, Ottawa, ON, K1A 0K9, Canada; School of Epidemiology and Public Health, University of Ottawa, Alta Vista Campus, 600 Peter Morand Cres. Room 101, Ottawa, ON, K1G 5Z3, Canada. Electronic address: eric.lavigne@canada.ca.
⁹ Department of Environmental and Occupational Health, Public Health Ontario, 480 University Ave. Suite 300, Toronto, ON, M5G 1V2, Canada; Dalla Lana School of Public Health, University of Toronto, 155 College St. Room 500, Toronto, ON, M5T 3M7, Canada. Electronic address: ray.copes@oahpp.ca.
¹⁰ Department of Physics and Atmospheric Science, Dalhousie University, Sir James Dunn Bldg, 6310 Coburg Rd., Halifax, NS, B3H 4J5, Canada. Electronic address: randall.martin@dal.ca.
¹¹ Department of Environmental and Occupational Health, Public Health Ontario, 480 University Ave. Suite 300, Toronto, ON, M5G 1V2, Canada; ICES, 2075 Bayview Ave. G1 06, Toronto, ON, M4N 3M5, Canada; Dalla Lana School of Public Health, University of Toronto, 155 College St. Room 500, Toronto, ON, M5T 3M7, Canada. Electronic address: hong.chen@oahpp.ca.

PMID: 32344208
DOI: 10.1016/j.envres.2020.109520

Abstract

Introduction: It is unknown whether urban green space is associated with reduced risk of major neurological conditions, especially dementia and stroke.

Methods: Retrospective, population-based cohorts were created for each study outcome, including 1.7 and 4.3 million adults in Ontario, Canada for dementia and stroke, respectively. Residential green space was quantified using the satellite-derived Normalized Difference Vegetation Index. Incidence was ascertained using health administrative data with validated algorithms. Mixed-effects Cox models were used to estimate hazard ratios per interquartile range increase in green space exposure.

Results: Between 2001 and 2013, 219,013 individuals were diagnosed with dementia and 89,958 had a stroke. The hazard ratio per interquartile range increase in green space was 0.97 (95% CI: 0.96-0.98) for dementia and 0.96 (0.95-0.98) for stroke. Estimates remained generally consistent in sensitivity analyses.

Discussion: Increased exposure to urban green space was associated with reduced incidence of dementia and stroke. To our knowledge, this is the first population-based cohort study to assess these relationships.

Keywords: Dementia; Neurological health; Residential green space; Stroke.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Cohort Studies
Dementia* / epidemiology
Humans
Ontario / epidemiology
Retrospective Studies
Stroke* / epidemiology

Grants and funding

MOP-133463/CAPMC/ CIHR/Canada