Green Spaces nationwide and communicable/non-communicable diseases
Journal Artical

Thinking beyond general greenness: The nuanced associations between a variety of greenspaces and cardiovascular diseases across urbanicity
Landscape and Urban Planning, 2024, IF= 7.9
Cardiovascular diseases (CVDs) are the leading causes of death globally. Exposure to greenspaces has been proposed to be beneficial for CVDs. However, past studies have often overlooked how varying levels of urbanicity may differently impact the relationships between greenspaces and cardiovascular health. Moreover, different types of greenspaces uniquely affect people’s behaviors and psychological wellbeing, potentially yielding distinct effects on CVDs.
This study investigates the associations between population-weighted exposure to various types of greenspaces and prevalence of coronary heart disease (CHD) and stroke in the US at tract level, and whether these associations are modified by urbanicity.
We identified a contrasting difference in health effects between greenspaces inside and outside park. Neighbourhoods with more forest (CHD β = −2.99, 95 % CI: −4.25, −1.73; stroke β = −1.85, 95 % CI: −2.56, −1.13) and open space (CHD β = −4.31, 95 % CI: −5.49, −3.14; stroke β = −2.33, 95 % CI: −3.00, −1.66) inside park were associated with a lower prevalence of CVDs, whereas more forest (CHD β = 7.67, 95 % CI: 5.81, 9.54; stroke β = 3.01, 95 % CI: 1.95, 4.07) and open space (CHD β = 11.52, 95 % CI: 9.99, 13.05; stroke β = 5.77, 95 % CI:4.90, 6.64) outside park were associated with a higher prevalence of CVDs. We observed a reversal pattern across urbanicity: the significant beneficial associations only held in highly urbanized tracts but attenuated or reversed in the three less urbanized tracts.
These findings highlight a need to prioritize investment in parks within walking distance to urban residents and improve the accessibility and design of rural greenspaces. We propose the Landscape Compensation Effect, which may serve as a new theoretical framework to guide future research and design practices of greenspaces to promote the cardiovascular health of both urban and rural residents.

Racial disparities in environmental exposures and SARS-CoV-2 infection rates: A detailed population-weighted analysis
Sustainable Cities and Society, 2024, IF= 11.7
The COVID-19 pandemic has cast a spotlight on the intersection of socio-economic, demographic, and environmental factors with public health, particularly in the context of SARS-CoV-2 infection rates. A gap remains in understanding how racial disparities in environmental exposure correlate with racial disparities in infection rates. This study bridges this gap by analyzing infection data for black and white populations across 1,416 counties in the contiguous United States, utilizing high-resolution land cover data and racial population maps to assess environmental exposure disparities. We found significant connections between racial disparities in environmental exposure and SARS-CoV-2 infection rates, even after accounting for population density, socio-economic status, and demographic factors. Disparities among black and white population’s access to green spaces, such as non-park forests and pasture/hay areas, as well as to developed areas of varying intensities, closely mirror racial disparities in infection rates. Crucially, we found that smaller differences in environmental exposure between races are associated with smaller differences in infection rates. This relationship is most pronounced within a 400-meter radius, underscoring the critical role of proximity in the design of urban and landscape environments to promote public health equity.

Green spaces in highly urbanized tracts tied to lower prevalence of chronic respiratory diseases: A nationwide study across levels of urbanicity
Urban Forestry & Urban Greening, 2023, IF= 6.4

Population-weighted Exposure to Green Spaces Tied to Lower COVID-19 Mortality Rates: A Nationwide Dose-Response Study in the USA
Science of the Total Environment, 2022, IF= 10.75
The COVID-19 pandemic has caused a huge loss of human life globally. However, few studies investigated the link between exposure to green space and risk of COVID-19 mortality rate, while also distinguishing the effects of various types of green space, considering the spatial distribution of human population and green space, and identifying the optimal buffer distances of nearby green space. It is critical and pressing to fill these significant knowledge gaps to protect and promote billions of people’s health and life across the world.
This study adopted a negative binomial generalized linear mixed-effects model to examine the association between the ratios of various types of green space, population-weighted exposure to those various types of green space, and COVID-19 mortality rates across 3025 counties in the USA, adjusted for sociodemographic, pre-existing chronic disease, policy and regulation, behavioral, and environmental factors.
The findings show that greater exposure to forest was associated with lower COVID-19 mortality rates, while developed open space had mixed associations with COVID-19 mortality rates. Forest outside park had the largest effect size across all buffer distances, followed by forest inside park. The optimal exposure buffer distance was 1 km for forest outside park, with per one-unit of increase in exposure associated with a 9.9 % decrease in COVID-19 mortality rates (95 % confidence interval (CI): 6.9 %–12.8 %). The optimal exposure buffer distance of forest inside park was 400 m, with per one-unit of increase in exposure associated with a 4.7 % decrease in mortality rates (95 % CI: 2.4 %–6.9 %).
The results suggest that greater exposure to green spaces, especially to nearby forests, may mitigate the risk of COVID-19 mortality. Although findings of an ecological study cannot be directly used to guide medical interventions, this study may pave a critical new way for future research and practice across multiple disciplines.

Built environment factors moderate pandemic fatigue in social distance during the COVID-19 pandemic: A nationwide longitudinal study in the United States
Landscape and Urban Planning, 2023, IF= 8.119
Non-pharmaceutical interventions (NPIs) remain some of the most effective measures for coping with the ever-changing coronavirus disease 2019 (COVID-19) pandemic. Pandemic fatigue, which manifests as the declined willingness to follow the recommended protective behaviors (e.g., keeping social distance policies, wearing masks), has commanded increasing attention from researchers and policymakers after the prolonged NPIs and COVID-19 worldwide. However, long-term changes in pandemic fatigue are not well understood, especially amidst the ever-changing pandemic landscape. Built environment factors have been shown to positively affect mental and physical health, but it is still unclear whether built environments can moderate pandemic fatigue. In this study, we used Google mobility data to investigate longitudinal trends of pandemic fatigue in social distance since the onset of NPIs enforcement in the United States. The results indicated that pandemic fatigue continuously worsened over nearly two years of NPIs implementation, and a sharp increase occurred after the vaccination program began. Additionally, we detected a significant moderation effect of greenspace and urbanicity levels on pandemic fatigue. People living in areas with high levels of greenness or urbanicity experienced lower levels of pandemic fatigue. These findings not only shed new light on the effects of greenness and urbanicity on COVID-19 pandemic fatigue, but also provide evidence for developing more tailored and effective strategies to cope with pandemic fatigue.

Green spaces, especially nearby forest, may reduce the SARS-CoV-2 infection rate: A nationwide study in the United States
Landscape and Urban Planning, 2022, IF= 8.119
The coronavirus pandemic is an ongoing global crisis that has profoundly harmed public health. Although studies found exposure to green spaces can provide multiple health benefits, the relationship between exposure to green spaces and the SARS-CoV-2 infection rate is unclear. This is a critical knowledge gap for research and practice. In this study, we examined the relationship between total green space, seven types of green space, and a year of SARS-CoV-2 infection data across 3,108 counties in the contiguous United States, after controlling for spatial autocorrelation and multiple types of covariates. First, we examined the association between total green space and SARS-CoV-2 infection rate. Next, we examined the association between different types of green space and SARS-CoV-2 infection rate. Then, we examined forest–infection rate association across five time periods and five urbanicity levels. Lastly, we examined the association between infection rate and population-weighted exposure to forest at varying buffer distances (100m to 4km). We found that total green space was negative associated with the SARS-CoV-2 infection rate. Furthermore, two forest variables (forest outside park and forest inside park) had the strongest negative association with the infection rate, while open space variables had mixed associations with the infection rate. Forest outside park was more effective than forest inside park. The optimal buffer distances associated with lowest infection rate are within 1,200m for forest outside park and within 600m for forest inside park. Altogether, the findings suggest that green spaces, especially nearby forest, may significantly mitigate risk of SARS-CoV-2 infection.

Green Spaces Mitigate Racial Disparity of Health: A Higher Ratio of Green Spaces Indicates a Lower Racial Disparity in SARS-CoV-2 Infection Rates in the USA
Environment International, 2021, IF= 13.352
There is striking racial disparity in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in the United States. We hypothesize that the disparity is significantly smaller in areas with a higher ratio of green spaces. County level data on the SARS-CoV-2 infection rates of black and white individuals in 135 of the most urbanized counties across the United States were collected. The total population in these counties is 132,350,027, comprising 40.3% of the U.S. population. The ratio of green spaces by land-cover type in each county was extracted from satellite imagery. A hierarchical regression analysis measured cross-sectional associations between racial disparity in infection rates and green spaces, after controlling for socioeconomic, demographic, pre-existing chronic disease, and built-up area factors. We found a higher ratio of green spaces at the county level is significantly associated with a lower racial disparity in infection rates. Four types of green space have significant negative associations with the racial disparity in SARS-CoV-2 infection rates. A theoretical model with five core mechanisms and one circumstantial mechanism is presented to interpret the findings.

Cardiovascular Diseases Due to Stress Arisen from Social Risk Factors: A Synopsis and Prospectiveness
Nano LIFE, 2018
This paper reviews the causes of cardiovascular diseases (CVD) from a perspective other than traditional clinical pathology. We look at social factors that could arouse stressful feelings, and could further lead to cardiovascular diseases. Major social factors including job stress, daily hassles, life events, social inequity and trauma are covered in our review. This paper also discusses potential interventions which could be taken by environmental professionals to create dynamism within the existing static structures so as to eventually eradicate the causes of mental stress and ameliorate the quality of life for urban dwellers.