Greenspace exposure and COVID-19 mortality in the United States: January-July 2020

Helen Russette; Jon Graham; Zachary Holden; Erin O Semmens; Elizabeth Williams; Erin L Landguth

doi:10.1016/j.envres.2021.111195

Greenspace exposure and COVID-19 mortality in the United States: January-July 2020

Environ Res. 2021 Jul:198:111195. doi: 10.1016/j.envres.2021.111195. Epub 2021 Apr 28.

Authors

Helen Russette¹, Jon Graham², Zachary Holden³, Erin O Semmens⁴, Elizabeth Williams⁵, Erin L Landguth⁴

Affiliations

¹ Center for Population Health Research, School of Public and Community Health Sciences, University of Montana, 32 Campus Drive, Missoula, MT, 59812, USA. Electronic address: helen.russette@mso.umt.edu.
² Center for Population Health Research, School of Public and Community Health Sciences, University of Montana, 32 Campus Drive, Missoula, MT, 59812, USA; Mathematical Sciences, University of Montana, 32 Campus Drive, Missoula, MT, 59812, USA.
³ US Forest Service, Missoula, MT, 59807, USA.
⁴ Center for Population Health Research, School of Public and Community Health Sciences, University of Montana, 32 Campus Drive, Missoula, MT, 59812, USA.
⁵ Center for Population Health Research, School of Public and Community Health Sciences, University of Montana, 32 Campus Drive, Missoula, MT, 59812, USA; All Nations Health Center, Missoula, MT, 59801, USA.

Abstract

Background: Mortality from the novel coronavirus disease-2019 (COVID-19) continues to rise across the United States. Evidence is emerging that environmental factors may contribute to susceptibility to disease and mortality. Greenspace exposure promotes enhanced immunity and may protect against risk of mortality among those with COVID-19.

Objectives: Our objective was to determine if high county level greenspace exposure is associated with reduced risk of COVID-19 mortality.

Methods: Greenspace exposure was characterized in 3049 counties across the conterminous United States using Leaf Area Index (LAI) deciles that were derived from satellite imagery via Moderate Resolution Imaging Spectroradiometer from 2011 to 2015. COVID-19 mortality data were obtained from the Center for Systems Science and Engineering at Johns Hopkins University. We used a generalized linear mixed model to evaluate the association between county level LAI and COVID-19 mortality rate in analyses adjusted for 2015-2019 county level average total county population, older population, race, overcrowding in home, Medicaid, education, and physical inactivity.

Results: A dose-response association was found between greenness and reduced risk of COVID-19 mortality. COVID-19 mortality was negatively associated with LAI deciles 8 [MRR = 0.82 (95% CI: 0.72, 0.93)], 9 [MRR = 0.78 (95% CI: 0.68, 0.89)], and 10 [MRR = 0.59 (95% CI: 0.50, 0.69)]. Aside from LAI decile 5, no associations were found between the remaining LAI deciles and COVID-19 mortality. Increasing prevalence of counties with older age residents, low education attainment, Native Americans, Black Americans, and housing overcrowding were significantly associated with increased risk of COVID-19 mortality, whereas Medicaid prevalence was associated with a reduced risk.

Discussion: Counties with a higher amount of greenspace may be at a reduced risk of experiencing mortality due to COVID-19.

Keywords: LAI; MODIS; Respiratory health; SARS-CoV-2.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Aged
Black or African American
COVID-19*
Educational Status
Humans
Parks, Recreational*
SARS-CoV-2
United States / epidemiology

Grants and funding

P20 GM130418/GM/NIGMS NIH HHS/United States