Neighborhood Greenness Research Articles

Older Adults' Outdoor Walking and Inequalities in Neighbourhood Green Spaces Characteristics.

Outdoor walking has considerable benefits for healthy ageing and older adults are recommended to walk regularly. However, older adults living in high-deprivation areas walk less than those living in low-deprivation areas. Previous research has shown that the characteristics of neighbourhood green spaces (i.e., proximity, attractiveness, size, and number) may influence outdoor walking. This study examines spatial inequalities in the characteristics of neighbourhood green spaces in high- versus low-deprivation areas and their possible influences on disparities in older adults’ outdoor walking levels. For this purpose, it included a sample of 173 participants (≥65 years) and used secondary data and a geographic information system (GIS) to objectively measure neighbourhood green spaces characteristics. Geographic positioning system (GPS) technology was used to objectively measure outdoor walking levels. Data on participants’ personal characteristics were collected by questionnaire. The results indicate that one characteristic of neighbourhood green spaces (i.e., size) is positively related to outdoor walking levels. They show that inequalities in neighbourhood green spaces’ size in high- versus low-deprivation areas may influence disparities in older adults’ outdoor walking levels. Despite inequalities in other neighbourhood green space characteristics (e.g., proximity, attractiveness, and number) in high- versus low-deprivation areas, no relationship was found between these neighbourhood green space characteristics and participants’ outdoor walking levels. Enhancing the distribution or creation of large neighbourhood green spaces (e.g., through creating green space networks) may enhance outdoor walking among older residents, especially in high-deprivation areas.

Mapping three decades of annual irrigation across the US High Plains Aquifer using Landsat and Google Earth Engine

Understanding how irrigated areas change over time is vital to effectively manage limited agricultural water resources, but long-term, high-resolution, and spatially explicit datasets are rare. The High Plains Aquifer (HPA) in the central United States is one of the largest and most stressed aquifer systems in the world. It supports a $20 billion economy, but groundwater use is unsustainable over much of the aquifer. Emerging cloud computing tools like Google Earth Engine (GEE) make it possible to use the full Landsat record to monitor regional systems like the HPA with high spatial and temporal resolution over multiple decades. However, challenges remain to develop irrigation classification methods that are robust to a wide range of climate conditions and crop types, evolving management, and missing data. Here, we addressed these challenges to produce an annual, moderately high resolution (30 m) irrigation map time series from 1984 to 2017 over the aquifer. Leveraging GEE's extensive data catalog, we combined Landsat imagery, environmental covariables, and a large heterogeneous ground truth dataset to create a single random forest classifier applied annually to the entire region. Following classification, we applied the Bayesian Updating of Land-Cover (BULC) algorithm to fill imagery gaps and reduce commission errors in the provisional irrigation time series. Novel neighborhood greenness indices contributed to an overall 91.4% map accuracy across years; county statistics (r2 = 0.86) were similarly well-matched. Trend analysis of irrigated area through time identified regions of stable, expanding, and declining irrigated area. Given declining aquifer storage, we estimate that up to 24% of currently irrigated area may be lost this century. To date, the map dataset is the longest, highest resolution large-scale record of where and when irrigation occurs. It is freely available for stakeholders, managers, and researchers to inform policies and management decisions, as well as for use in hydrology, agronomy, and climate models.

Exploring the Quality of Urban Green Spaces Based on Urban Neighborhood Green Index—A Case Study of Guangzhou City

Urban green space (UGS), as a form of green infrastructure, has been given increasing attention in urban planning and its policies. The quality of a UGS is fundamental for the sustainable development of the urban economy, society, environment, and quality of human life, although UGS is unevenly distributed within cities. Aiming to analyze the quality of UGS at the scale of Jiedaos in China, this paper took Haizhu district in Guangzhou as a case study based on collected data from 2010 and aerial imagery from 2012. The Urban Neighborhood Green Index (UNGI) was established by combining four weighted parameters: the green index (P1), the density of buildings (P2), proximity to green areas (P3) and building height (P4). Results from comparing with green index show that (1) the UNGI performed better for UGS planning due to its ability of uncovering impact of the built environment and its accessibility on quality of UGS; (2) the UGS has significant effects on neighbors, which underlies social inequity of UGS supply and presents rich information for urban planning and decision making; (3) a small green field attaching to a community plays a key role in fulfilling the need of neighbors for green space, fitness, and leisure in China, which is usually ignored due to the ownership of private property. It suggests recognizing UGS and improving its quality in old towns as well as improving urban villages characterized by poor quality of green space with green infrastructures. The UNGI can inform city planners regarding their consideration of UGS, and it can contribute to measurements of sustainability and the development of green infrastructure.

What Is the Relationship between the Neighbourhood Built Environment and Time Spent in Outdoor Play? A Systematic Review

Outdoor play has been associated with children’s and adolescents’ healthy development and physical activity. Attributes of the neighbourhood built environment can influence play behaviours. This systematic review examined the relationship between attributes of the neighbourhood built environment and the time children and adolescents (0–18 years) spend in self-directed outdoor play. We identified and evaluated 18 relevant papers using the Mixed Methods Appraisal Tool and developed a narrative synthesis of study results. We found moderate evidence that lower traffic volumes (ages 6–11), yard access (ages 3–10), and increased neighbourhood greenness (ages 2–15) were positively associated with time spent in outdoor play, as well as limited evidence that specific traffic-calming street features such as fewer intersections, low traffic speeds, neighbourhood disorder, and low residential density were positively associated with time spent in outdoor play. To our knowledge, this is the first systematic review on this topic. The limited number of “good quality” studies identified highlights the need for additional research on the topic.

Association between neighborhood greenspace and fasting plasma glucose from a large cohort study in Taiwan

Growing evidence suggests that greenness exposure improves health status, but few studies address diabetes, and research mainly comes from Western countries. This study hypothesizes that higher greenness exposure benefits glucose control with increased intensity of physical activity. We used data from a longitudinal health examination database in Taiwan during 2000–2014. The normalized difference vegetation index (NDVI) was used as an objective indicator of greenness in the neighborhood. Fasting plasma glucose served as an indicator of early diabetes diagnosis. A metabolic equivalent value (MET) based on a compendium of physical activities was used to estimate the intensity of physical activity. We applied a linear mixed-effect model with an individual-level random effect to investigate the relationship between neighborhood greenness and the fasting plasma glucose value stratified by four levels of physical activity. There are 341,211 participants with no diabetes, and 773,602 check-up visits included here. The fasting glucose among participants living in areas with higher green space was lower than that of those living in less green areas. The beneficial effects of greenspace on glucose were stronger for those with more physical activity, especially in the 500-m buffer. In the physically inactive group, compared with the lowest quantile (Q1) of cumulative average greenness, people living in the highest quantile (Q4) of greenness had 0.35 mg less glucose in each dl of plasma [95% confidence interval: −0.50, −0.20]. In the physically active group, people residing in the highest quantile (Q4) of greenness had 0.48 mg less glucose in each dl of plasma [95% confidence interval: −0.73, −0.23]. Higher residential greenness appears to be associated with lower glucose. Higher physical activity can mediate this association. Our results provide evidence that ensuring access to greenspace in residential neighborhoods may provide positive health outcomes and improve public health, and should be implemented in urban planning.

The greener the better? Does neighborhood greenness buffer the effects of stressful life events on externalizing behavior in late adolescence?

We tested whether neighborhood greenness is a promotive and/or a protective factor in the development of adolescent externalizing behavior problems and explored a possible mechanism of its effects via respiratory sinus arrhythmia (RSA) recovery after stress. Data from a longitudinal multi-method study on adolescents (N = 715) was used. Result showed that neighborhood greenness was neither a promotive nor a protective factor. However, adolescents who reported more stressful life events showed more externalizing behavior and -contrary to our expectation- this effect was stronger for adolescents who grew up in greener neighborhoods (vs. less green neighborhoods).

Neighbourhood greenness and mental wellbeing in Guangzhou, China: What are the pathways?

Rapid urbanization in China has diminished urban residents’ opportunities to connect with nature and thereby posed a great threat to their mental wellbeing. While a plethora of studies have disentangled the positive relationship between neighbourhood greenness and mental wellbeing in developed countries, scant attention has been paid to pathways through which neighbourhood greenness affects mental wellbeing among Chinese urban residents. This study aims to systematically explore biopsychosocial pathways linking exposure to neighbourhood greenness to mental wellbeing using survey data collected from 35 neighbourhoods of Guangzhou, China. It uses the Normalized Difference Vegetation Index (NDVI) as the surrogate for residential exposure to greenness, thereby enabling the comparison between China and other countries. Results from Structural Equation Modelling show that exposure to neighbourhood greenness is positively associated with mental wellbeing. Results also suggest that, consistent with what is known, promotion of walking, facilitation of social cohesion and satisfaction with neighbourhood greenspace play separate roles in mediating the protective effect of neighbourhood greenness. However, in contrast to previous findings from developed countries, this study finds no evidence to indicate that reduction in stress and mitigation of air/noise pollution are pathways linking exposure to greenness to mental wellbeing. Our findings suggest the necessity of building sufficient green infrastructure at the neighbourhood scale in promoting mental wellbeing in Chinese urban settings.

Neighbourhood greenness and depression among older adults.

Neighbourhood greenness or vegetative presence has been associated with indicators of health and well-being, but its relationship to depression in older adults has been less studied. Understanding the role of environmental factors in depression may inform and complement traditional depression interventions, including both prevention and treatment.AimsThis study examines the relationship between neighbourhood greenness and depression diagnoses among older adults in Miami-Dade County, Florida, USA. Analyses examined 249 405 beneficiaries enrolled in Medicare, a USA federal health insurance programme for older adults. Participants were 65 years and older, living in the same Miami location across 2 years (2010-2011). Multilevel analyses assessed the relationship between neighbourhood greenness, assessed by average block-level normalised difference vegetative index via satellite imagery, and depression diagnosis using USA Medicare claims data. Covariates were individual age, gender, race/ethnicity, number of comorbid health conditions and neighbourhood median household income. Over 9% of beneficiaries had a depression diagnosis. Higher levels of greenness were associated with lower odds of depression, even after adjusting for demographics and health comorbidities. When compared with individuals residing in the lowest tertile of greenness, individuals from the middle tertile (medium greenness) had 8% lower odds of depression (odds ratio 0.92; 95% CI 0.88, 0.96; P = 0.0004) and those from the high tertile (high greenness) had 16% lower odds of depression (odds ratio 0.84; 95% CI 0.79, 0.88; P < 0.0001). Higher levels of greenness may reduce depression odds among older adults. Increasing greenery - even to moderate levels - may enhance individual-level approaches to promoting wellness.Declaration of interestNone.

Neighbourhood greenness and birth outcomes in a Swedish birth cohort - A short communication.

The present study investigated whether associations between greenness and birth outcomes can be detected in children belonging to a Swedish birth cohort (BAMSE). Normalized difference vegetation index (NDVI) within a 500 m buffer zone around maternal address was used as estimate of greenness. Ordinary least squares and quantile regression models were performed to investigate associations between neighbourhood NDVI and birthweight (n = 2619), birth length (n = 2490) and head circumference (n = 2243). Logistic regression analyses were used to detect the association between NDVI and odds of being born as "small-" or "large-for-gestational-age". There were no clear associations between NDVI and birth weight in the total sample. However, in a suburban sub-sample, increased NDVI levels were significantly associated with elevated birthweight of small new-borns (β2nd percentile = 276 g, 95% CI 61 to 492, p = 0.012), and significantly reduced the odds ratio (OR) for children being born as small-for-gestational-age (OR = 0.31 95% CI 0.1 to 1, p = 0.049). No significant associations were found between NDVI and birth length or head circumference. In conclusion, neighbourhood greenness appears not to be associated with birthweight as such, but rather decrease the odds of being born underweight, in particular in suburban areas.

Community greenness and neurobehavioral health in children and adolescents

BackgroundNeighborhood greenness appears to be beneficial to human health. However, there are few studies on the relationship between greenness of children's residential communities and their neurobehavioral health. ObjectiveIn this cross-sectional study, we examined the association between neighborhood greenness of children's residential area and their neurobehavioral health. MethodsWe used a population-representative sample of school children (n = 1817) from 2012 and 2013 in South Korea. Parents or guardians of children completed the Child Behavior Checklist (CBCL) to assess their children's neurobehavioral health. As a measurement for greenness, the modified soil-adjusted vegetation index (MSAVI) at a 30-m resolution was retrieved from the Landsat satellite data operated by NASA. The MSAVI values were categorized into tertiles (low, moderate, high greenness) and each child was assigned the mean MSAVI within a 1.6-km radius of residence. We applied survey regressions of the CBCL transformed scores on the 3 levels of greenness, controlling for age, sex, physical activity, monthly family income, exposure to second-hand smoke, exposure to NO2, and blood lead level. ResultsHigh greenness was associated with a lower Total CBCL score compared to low greenness (−2.33, 95% CI, −4.10 to −0.56). Externalizing Behavior showed a slightly stronger association with greenness than did Internalizing Behavior. The inverse relationship with greenness was strongest for Attention Problems (−1.32; 95% CI: -2.58, −0.06). The magnitudes of the association were strongest when the buffer distance was 1600 m. ConclusionsGreenness of residential neighborhood was associated with lower problematic behavior scores in children, especially aggressive behaviors and attention problems.

Abstract P098: The Relationship of Neighborhood Greenness to Heart Disease in 249,405 US Medicare Beneficiaries

Background: Nature exposures may be associated with reduced risk for heart disease. The present study examines the relationship between objective measures of neighborhood greenness (vegetative presence) and diagnoses of four forms of heart disease (acute myocardial infarction [AMI], ischemic heart disease, heart failure, and atrial fibrillation), in a large population-based sample of Medicare beneficiaries in Miami-Dade County, Florida. Methods: The sample included 249,405 Medicare beneficiaries ages 65 years and older whose location (ZIP+4) in Miami-Dade County, Florida, did not change from 2010 to 2011. Analyses examined relationships between greenness, measured by mean Normalized Difference Vegetation Index (NDVI) from satellite imagery at the Census block level, and four forms of heart disease in 2011. A series of hierarchical regression analyses, in a multi-level framework, assessed the relationship of greenness to each heart disease diagnosis, adjusting successively for individual sociodemographics and neighborhood median household income. A further final model adjusted for biological risk factors (diabetes, hypertension, and hyperlipidemia). Results: Higher greenness was generally associated with reduced risk of heart disease, in models adjusting for individual sociodemographics and neighborhood income: When compared to the lowest tertile of greenness, the highest tertile of greenness was associated with statistically significant (ps<.01) reduced odds of AMI by 25% (OR=0.75; 95% CI: 0.63, 0.90), ischemic heart disease by 20% (OR=0.80; 95% CI: 0.77, 0.83), heart failure by 16% (OR=0.84; 95% CI: 0.80, 0.88), and a marginally significant reduced odds of atrial fibrillation by 6% (OR=0.94; 95% CI: 0.87, 1.00, p=.067). In addition, the highest tertile of greenness was associated with 19% reduced odds of any of the four forms of heart disease (OR=0.81; 95% CI: 0.78, 0.84) when compared to the lowest tertile of greenness, adjusting for individual sociodemographics and neighborhood income. These associations were attenuated in a final model which added biological risk factors, suggesting that cardiometabolic risk factors may at least partly mediate the observed relationships between greenness and heart disease. Conclusions: Even after adjusting for individual sociodemographics and neighborhood income, neighborhood greenness may be associated with reduced odds of heart disease, possibly as a result of increased time spent outdoors, physical activity, stress mitigation, and/or air pollution. Results suggest that strategies to reduce inequities in area greenness and improve public access to these areas may be a future means of reducing heart disease at the population level.

Relationship of Neighborhood Greenness to Heart Disease in 249405 US Medicare Beneficiaries.

BackgroundNature exposures may be associated with reduced risk of heart disease. The present study examines the relationship between objective measures of neighborhood greenness (vegetative presence) and 4 heart disease diagnoses (acute myocardial infarction, ischemic heart disease, heart failure, and atrial fibrillation) in a population‐based sample of Medicare beneficiaries.Methods and ResultsThe sample included 249 405 Medicare beneficiaries aged 65 years and older whose location (ZIP+4) in Miami‐Dade County, Florida, did not change from 2010 to 2011. Analyses examined relationships between greenness, measured by mean block‐level normalized difference vegetation index from satellite imagery, and 4 heart disease diagnoses. Hierarchical regression analyses, in a multilevel framework, assessed the relationship of greenness to each heart disease diagnosis, adjusting successively for individual sociodemographics, neighborhood income, and biological risk factors (diabetes mellitus, hypertension, and hyperlipidemia). Higher greenness was associated with reduced heart disease risk, adjusting for individual sociodemographics and neighborhood income. Compared with the lowest tertile of greenness, the highest tertile of greenness was associated with reduced odds of acute myocardial infarction by 25% (odds ratio, 0.75; 95% CI, 0.63–0.90), ischemic heart disease by 20% (odds ratio, 0.80; 95% CI, 0.77–0.83), heart failure by 16% (odds ratio, 0.84; 95% CI, 0.80–0.88), and atrial fibrillation by 6% (odds ratio, 0.94; 95% CI, 0.87–1.00). Associations were attenuated after adjusting for biological risk factors, suggesting that cardiometabolic risk factors may partly mediate the greenness to heart disease relationships.ConclusionsNeighborhood greenness may be associated with reduced heart disease risk. Strategies to increase area greenness may be a future means of reducing heart disease at the population level.

Neighborhood Greenness Attenuates the Adverse Effect of PM2.5 on Cardiovascular Mortality in Neighborhoods of Lower Socioeconomic Status.

Features of the environment may modify the effect of particulate matter ≤2.5 µm in aerodynamic diameter (PM2.5) on health. Therefore, we investigated how neighborhood sociodemographic and land-use characteristics may modify the association between PM2.5 and cardiovascular mortality. We obtained residence-level geocoded cardiovascular mortality cases from the Massachusetts Department of Public Health (n = 179,986), and PM2.5 predictions from a satellite-based model (2001–2011). We appended census block group-level information on sociodemographic factors and walkability, and calculated neighborhood greenness within a 250 m buffer surrounding each residence. We found a 2.54% (1.34%; 3.74%) increase in cardiovascular mortality associated with a 10 µg/m3 increase in two-day average PM2.5. Walkability or greenness did not modify the association. However, when stratifying by neighborhood sociodemographic characteristics, smaller PM2.5 effects were observed in greener areas only among cases who resided in neighborhoods with a higher population density and lower percentages of white residents or residents with a high school diploma. In conclusion, the PM2.5 effects on cardiovascular mortality were attenuated by higher greenness only in areas with sociodemographic features that are highly correlated with lower socioeconomic status. Previous evidence suggests health benefits linked to neighborhood greenness may be stronger among lower socioeconomic groups. Attenuation of the PM2.5–mortality relationship due to greenness may explain some of this evidence.

Does genetic risk of obesity modify associations between the neighbourhood environment and body-mass index? A cross-sectional analysis of the UK Biobank dataset

BackgroundIn studies of gene–environment interactions and obesity, the term environment usually refers to individual behavioural factors that influence energy balance. However, evidence suggests that the built environments in which individuals live, work, and play are associated with obesity and may therefore be environmental triggers of genetic risk. No studies have explored whether individual response to such environmental determinants of obesity varies with genetic risk. We aimed to examine whether genetic risk of obesity modifies associations between various neighbourhood characteristics and body-mass index (BMI). MethodsOur sample included 245 532 adults aged 40–69 years from UK Biobank with cross-sectional data on neighbourhood exposures, BMI, potential confounders, and BMI-linked single nucleotide polymorphisms (SNPs). We derived a composite measure of residential neighbourhood environment based on proximity of fast-food stores, availability of physical activity facilities, and neighbourhood green-ness. We also examined each component separately. We constructed a genetic risk score (GRS) as the weighted average of 70 SNPs, where weights were published estimates of genetic effect sizes, scaled to account for the number of available SNPs. In adjusted mixed-effects regression models of neighbourhood environment–BMI associations we examined possible effect modification by genetic risk by testing GRS-by-neighbourhood measure interaction terms and estimating GRS-stratified associations. FindingsSome evidence of an interaction with genetic risk was observed for the composite measure (pinteraction=0·040); the magnitude of the main association with BMI was somewhat larger among people in the highest genetic risk quintile (0·12 lower BMI for each unit increase in composite score [95% CI −0·15 to −0·08]) compared with those in the lowest GRS quintile (β=–0·07; 95% CI −0·11 to −0·03). Less evidence of interaction was observed for the component neighbourhood exposures (fast-food proximity, availability of PA facilities, and neighbourhood greenness), but some results were sensitive (particularly fast-food proximity findings) to alternative model specification and GRS definitions. InterpretationThis preliminary analysis suggests that any gene–environment interaction is fairly weak. People at some levels of genetic risk of obesity might be more sensitive to some neighbourhood characteristics in combination. It is possible that obesogenic environments are so pervasive that low genetic risk affords limited protection. Results were sensitive to analytical decisions, and further examination of this possible gene–environment interaction is necessary. Measurement error in the neighbourhood exposures and UK Biobank's low response fraction remain potential sources of bias. FundingCommonwealth Scholarship Commission.

Might School Performance Grow on Trees? Examining the Link Between "Greenness" and Academic Achievement in Urban, High-Poverty Schools.

In the United States, schools serving urban, low-income students are among the lowest-performing academically. Previous research in relatively well-off populations has linked vegetation in schoolyards and surrounding neighborhoods to better school performance even after controlling for important confounding factors, raising the tantalizing possibility that greening might boost academic achievement. This study extended previous cross-sectional research on the “greenness”-academic achievement link to a public school district in which nine out of ten children were eligible for free lunch. In generalized linear mixed models, Light Detection and Ranging (LiDAR)-based measurements of green cover for 318 Chicago public schools predicted statistically significantly better school performance on standardized tests of math, with marginally statistically significant results for reading—even after controlling for disadvantage, an index combining poverty and minority status. Pupil/teacher ratio %bilingual, school size, and %female could not account for the greenness-performance link. Interactions between greenness and Disadvantage suggest that the greenness-academic achievement link is different for student bodies with different levels of disadvantage. To determine what forms of green cover were most strongly tied to academic achievement, tree cover was examined separately from grass and shrub cover; only tree cover predicted school performance. Further analyses examined the unique contributions of “school tree cover” (tree cover for the schoolyard and a 25 m buffer) and “neighborhood tree cover” (tree cover for the remainder of a school’s attendance catchment area). School greenness predicted math achievement when neighborhood greenness was controlled for, but neighborhood greenness did not significantly predict either reading or math achievement when school greenness was taken into account. Future research should assess whether greening schoolyards boost school performance.

The Association between Long-term Neighborhood Greenness and Lethal Prostate Cancer in a Prospective Cohort Study of Male Health Professionals in the United States

BackgroundEmerging literature documents health benefits of natural environments. We studied the association between neighborhood greenness and 26-year incidence of lethal prostate cancer (CaP), effect modification by address type (home or workplace), and mediation by vigorous physical activity.MethodsParticipants in the Health Professionals Follow-up Study, a nationwide prospective cohort, were followed from 1986 to 2012. We excluded those with history of CaP or missing address. Lethal CaP was defined by metastasis or CaP death. Neighborhood greenness was measured using normalized difference vegetation index (NDVI) with 1km2 resolution. Participants were assigned NDVI corresponding to their address at start of follow-up, taking averages over four seasonal measures. NDVI was modeled using quintiles. Data were analyzed using sequentially adjusted Cox regression models: 1) age, calendar year, race, family history, smoking, BMI at 21, PSA screening, census median income and home value, walkability index; 2) vigorous and non-vigorous physical activity, current BMI.Results46,494 participants met eligibility criteria. Men in greener neighborhoods at baseline experienced lower rates of lethal CaP (model 1: Q2 v Q1, aHR: 0.84, 95% CI: 0.67-1.05; Q3 aHR: 0.86, 95% CI: 0.69-1.07; Q4 aHR: 0.77, 95% CI: 0.61-0.97; Q5 aHR: 0.86, 95% CI: 0.69-1.09, ptrend=0.11). Protective associations were strongest among men (39%) reporting work addresses (Q2 v Q1, aHR: 0.73, 95% CI: 0.51-1.02; Q3 aHR: 0.61, 95% CI: 0.42-0.89; Q4 aHR: 0.55, 95% CI: 0.37-0.83; Q5 aHR: 0.65, 95% CI: 0.42-1.00, ptrend=0.0005). Further adjustment for mediators (model 2) did not change effect estimates.ConclusionsOur findings suggest a protective association between neighborhood greenness and lethal CaP independent of physical activity, though overall results were not statistically significant. Stronger associations at work suggest benefits may arise from passive rather than active engagement with nature.

Cardiovascular Diseases in Middle Aged and Older Adults in China: The Joint Effects and Mediation of Different Types of Physical Exercise and Neighborhood Greenness and Walkability

Both physical exercise and built environment have been associated with cardiovascular diseases (CVDs). Yet, few studies examined the influence of different types of physical exercise and multiple dimensions of built environment, their joint effects, and whether physical exercise mediates the effect of built environment on the risk of CVDs. We investigated different types of physical exercise and two important dimensions of built environment, namely greenness and walkability, on the risk of three common CVD outcomes (i.e. hypertension, coronary heart disease, and stroke) in a Chinese population aged 40 years or older. Data were collected for 1,944 residents from 32 communities across urban, suburban, and rural areas in Longzihu district of Bengbu, a typical second-tier city in China. Physical exercise was obtained from questionnaire surveys. Built environment factors included satellite-based Normalized Difference Vegetation Index (NDVI), Walk Score index, and questionnaire-based Neighborhood Environment Walkability Scale (NEWS). Multilevel logistic regression was used to estimate the associations of physical exercise and built environment with CVDs while accounting for within-community and within-subdistrict correlations and potential confounders. Significant associations were found for reduced risk of hypertension and coronary heart disease with walking/square dancing and Tai Chi, and reduced risk of stroke with walking/square dancing. Significant associations were also identified for reduced risk of hypertension, coronary heart disease and stroke with NDVI. Lower risk of hypertension and coronary heart disease was associated with higher Walk score; and lower risk of hypertension and stroke was associated with higher NEWS-based walkability score. We observed no interactions between physical exercise and the built environment, but physical exercise partially mediated the effects of greenness and walkability on the risk of CVDs.

How Green Is Green? Modeling Urban Greenness Exposure in Environmental Health Research

Exposure to greenness has several health benefits, yet analyses are limited by uncertainty about accuracy of greenness metrics, often derived from different remotely-sensed data sources and using different spatial methods. This research (1) assesses the strengths and weaknesses of multiple greenness data sources and metrics for application in environmental health research, and (2) develops and tests an alternative greenness exposure metric that can be applied worldwide.Methods:We analyzed 5 data sources: Landsat time series, Landsat 8, Sentinel-2, RapidEye, and the Green View Index (GVI), derived from Google Street View. These data sets span various time series, resolutions and costs, and represent aerial and perspective views. We compared the Normalized Difference Vegetation Index (NDVI) using different imagery types and the GVI for various buffer distances around postal codes and examined sensitivity to spatial metrics and data sources. Based on these analyses, we constructed a spatially-weighted greenness metric combining data from Sentinel-2 and the GVI that incorporates neighbourhood street-level and at-home greenness.Results:NDVI showed correlations of between 0.65 and 0.85 among satellite types and demonstrated significant inter-variability. GVI showed low correlations with all other data types (0.25-0.40), suggesting an important new source of greenness data. Metrics were spatially sensitive, particularly at small distances and high resolutions, but lacked temporal sensitivity. Initial analyses suggest that the proposed metric is superior to traditional measures that overestimate neighbourhood greenness exposure and underestimate at-home exposure.Conclusions:This research is the first comparison of multiple remote sensing data sources and metrics, including both aerial and novel perspective views. It presents an alternative greenness exposure metric based on freely accessible data sources that may be applied in public health research internationally.

The Relationship between Long-term Exposure to Neighbourhood Greenness and Air Pollution and Cardiovascular Mortality in Urban Areas in Belgium

BackgroundFew large-scale studies have evaluated the association between residential green, air pollution and cause-specific mortality. Our study investigates the relationship between long-term res...

Cardiovascular diseases in middle aged and older adults in China: the joint effects and mediation of different types of physical exercise and neighborhood greenness and walkability

BackgroundBoth physical exercise and the built environment are associated with cardiovascular diseases (CVDs). Yet, the influence of the multiple dimensions of the built environment and different types of physical exercise on CVDs is not well understood. Further, little is known about the joint effects of physical exercise and the built environment, nor whether one mediates the effect of the other on the risk of CVDs. We aim to investigate the risk of CVDs on middle aged and older Chinese adult populations by analyzing the independent effects, as well as potential interactions and mediation effects of different types of physical exercise and two dimensions of the built environment; namely, greenness and walkability. MethodsData were collected from a community-based cross-sectional study (n = 1944). The study participants, aged 40 years or older, came from 32 communities across urban, suburban, and rural areas in Longzihu district of Bengbu, a typical second-tier city in eastern China. Physical exercise data were obtained from the International Physical Activity Questionnaire (IPAQ) question survey. We used a satellite-based Normalized Difference Vegetation Index (NDVI) score to assess greenness exposure. We used both the Walk Score index and the Neighborhood Environment Walkability Scale (NEWS) to assess walkability. Multilevel logistic regression, also known as mixed-effects logistic regression, was used to estimate the associations between physical exercise and the built environment (greenness and walkability) on CVD outcomes while accounting for within-community and within-subdistrict correlations. We followed Baron and Kenny's framework and used bootstrapping to quantify the mediation of physical exercise between built environment and CVD outcomes. Stratified analysis was conducted by age (middle aged and older adults) and gender. ResultsCompared to the reference group with little to low physical activities, we found a significantly reduced risk of hypertension (about 20–45% reduction) and coronary heart disease (about 35–55% reduction) among those with moderate to high activities in walking/square dancing or morning exercising/Tai Chi, and a significantly reduced risk of stroke (about 25% reduction) among those with moderate to high activities in walking/square dancing. Compared to the reference group with low NDVI-based greenness exposure, we found a significant reduction in risk of hypertension (about 55–85% reduction), coronary heart disease (about 75% reduction) and stroke (about 45% reduction) among those with moderate to high levels of exposure. Compared to the reference groups with low walkability, we observed about 30–60% lower risk of hypertension and coronary heart disease associated with moderate to high levels of Walk score, and about 20–30% lower risk of hypertension and stroke associated with moderate to high levels of NEWS-based walkability. We found no interactions between physical exercise and the built environment. The associations of greenness and walkability with CVDs were partially explained by physical exercise (up to 55% of the total effect). ConclusionsBoth physical exercise and built environment factors were associated with the risk of CVDs. Our observed association between CVDs and neighborhood greenness exposure and walkability was explained, in part, by physical exercises. Such a role, if confirmed in future studies, could have important implications for policies and programs aimed at increasing green spaces and improving walkability in both urban and rural settings as strategies to promote physical exercise in middle aged and older population.