Is tree loss associated with cardiovascular-disease risk in the Women's Health Initiative? A natural experiment

A scoping review of human health co-benefits of forest-based climate change mitigation in Europe

Climate change is a pressing global challenge with profound implications for human health. Forest-based climate change mitigation strategies, such as afforestation, reforestation, and sustainable forest management, offer promising solutions to mitigate climate change and simultaneously yield substantial co-benefits for human health. The objective of this scoping review was to examine research trends related to the interdisciplinary nexus between forests as carbon sinks and human health co-benefits. We developed a conceptual framework model, supporting the inclusion of exposure pathways, such as recreational opportunities or aesthetic experiences, in the co-benefit context. We used a scoping review methodology to identify the proportion of European research on forest-based mitigation strategies that acknowledge the interconnection between mitigation strategies and human impacts. We also aimed to assess whether synergies and trade-offs between forest-based carbon sink capacity and human co-benefits has been analysed and quantified. From the initial 4,062 records retrieved, 349 reports analysed European forest management principles and factors related to climate change mitigation capacity. Of those, 97 studies acknowledged human co-benefits and 13 studies quantified the impacts on exposure pathways or health co-benefits and were included for full review. Our analysis demonstrates that there is potential for synergies related to optimising carbon sink capacity together with human co-benefits, but there is currently a lack of holistic research approaches assessing these interrelationships. We suggest enhanced interdisciplinary efforts, using for example multideterminant modelling approaches, to advance evidence and understanding of the forest and health nexus in the context of climate change mitigation.

Why might urban tree canopy reduce dementia risk? A causal mediation analysis of 109,688 adults with 11 years of hospital and mortality records

Urban tree canopy is associated with lower dementia risk, but no mediation analysis has been attempted to reveal potential mechanisms. We examined 3,639 dementia diagnoses in 109,688 participants of the Sax Institute's 45 and Up Study. Adjusted models indicated ≥20% tree canopy lowered the odds of developing dementia by 14% over 11 years (Odds Ratio = 0.86, 95%CI = 0.79-0.93). Association between tree canopy and dementia was partially mediated by physical activity (4.5%) and absences of psychological distress (5.7%), social support (2.9%), sleep duration (2.3%) and diabetes (1.8%). Social loneliness and absence of heart disease or hypertension did not mediate the tree canopy-dementia association.

How do territorial characteristics affect spatial inequalities in the risk of coronary heart disease?

BACKGROUND

Cardiovascular diseases remain the leading cause of death and disabilities worldwide, with coronary heart diseases being the most frequently diagnosed. Their multifactorial etiology involves individual, behavioral and territorial determinants, and thus requires the implementation of multidimensional approaches to assess links between territorial characteristics and the incidence of coronary heart diseases.

CONTEXT AND OBJECTIVES

This study was carried out in a densely populated area located in the north of France with multiple sources of pollutants. The aim of this research was therefore to establish complex territorial profiles that have been characterized by the standardized incidence, thereby identifying the influences of determinants that can be related to a beneficial or a deleterious effect on cardiovascular health.

METHODS

Forty-four variables related to economic, social, health, environment and services dimensions with an established or suspected impact on cardiovascular health were used to describe the multidimensional characteristics involved in cardiovascular health.

RESULTS

Three complex territorial profiles have been highlighted and characterized by the standardized incidence rate (SIR) of coronary heart diseases after adjustment for age and gender. Profile 1 was characterized by an SIR of 0.895 (sd: 0.143) and a higher number of determinants that revealed favorable territorial conditions. Profiles 2 and 3 were characterized by SIRs of respectively 1.225 (sd: 0.242) and 1.119 (sd: 0.273). Territorial characteristics among these profiles of over-incidence were nevertheless dissimilar. Profile 2 revealed higher deprivation, lower vegetation and lower atmospheric pollution, while profile 3 displayed a rather privileged population with contrasted territorial conditions.

CONCLUSION

This methodology permitted the characterization of the multidimensional determinants involved in cardiovascular health, whether they have a negative or a positive impact, and could provide stakeholders with a diagnostic tool to implement contextualized public health policies to prevent coronary heart diseases.

Modifying Effect of Outdoor Recreational Activity on the Association Between Anger Expression and Cardiovascular Disease Risk: The Circulatory Risk in Communities Study

OBJECTIVE

Outdoor recreational activity (ORA) has been suggested as a practical strategy for anger management to moderate the risk of cardiovascular disease (CVD). However, there is a lack of evidence pertaining to this topic. Our aim was to examine whether ORA modified the association between anger expression and the risk of CVD.

METHODS

A community-based cohort study was conducted among 1877 Japanese individuals aged 40 to 79 years at baseline in 1997. The anger expression was measured using the Spielberger Anger Expression Scale. Stratified into low and high ORA (0 and ≥1 of the four behaviors), a Cox proportional hazards model was used to assess the anger expression-related risk of incident CVD (ischemic heart disease and stroke).

RESULTS

We identified 76 incident CVDs during a median follow-up of 18.8 years. Among participants with low ORA, anger expression was associated with an increased risk of CVD, whereas no association was identified among those with high ORA. The standardized hazard ratios were 1.53 (95% confidence interval, 1.23-1.91) and 0.77 (0.51-1.15) among those with low and high ORA, respectively ( p for interaction = .004). Similar associations were observed regarding the risk of total and ischemic stroke, and ischemic CVD.

CONCLUSIONS

We found an elevated risk of CVD associated with anger expression among participants with low ORA but not among those with high ORA, suggesting that ORA use may mitigate the association between anger expression and CVD risk.

Neighborhood greenspace and cognition: The cardiovascular health study

OBJECTIVES

We examined whether greenspace measures (overall percent greenspace and forest, and number of greenspace types) were associated with clinically adjudicated dementia status.

METHODS

In a sample of non-demented older adults (n = 2141, average age = 75.3 years) from the Cardiovascular Health and Cognition Study, Cox proportional hazard and logistic regression analyses were used to estimate associations of baseline greenspace with risks of incident dementia and MCI, respectively, while adjusting for demographics, co-morbidities, and other neighborhood factors. We derived quartiles of percent greenness (greenspace), forest (percent tree canopy cover), and tertiles of greenspace diversity (number of greenspace types) for 5-km radial buffers around participant's residences at study entry (1989-1990) from the 1992 National Land Cover Dataset. Dementia status and mild cognitive impairment (MCI) over 10 years was clinically adjudicated.

RESULTS

We observed no significant association between overall percent greenspace and risk of mild cognitive impairment or dementia and mostly null results for forest and greenspace diversity. Forest greenspace was associated with lower odds of MCI (OR quartile 4 versus 1: 0.54, 95% CI: 0.29-0.98) and greenspace diversity was associated with lower hazard of incident dementia (HR tertile 2 versus 1: 0.70, 95% CI = 0.50-0.99).

DISCUSSION

We found divergent results for different types of greenspace and mild cognitive impairment or dementia. Improved greenspace type and diversity measurement could better characterize the association between greenspace and cognition.

The association between tree planting and mortality: A natural experiment and cost-benefit analysis

Several recent longitudinal studies have found that exposure to the natural environment is associated with lower non-accidental mortality. However, most of these studies used the normalized difference vegetation index (NDVI) as an exposure metric; and because NDVI might not be sensitive enough to adequately capture changes in urban vegetation, these studies might lack true longitudinal variation in exposure. Therefore, we used a natural experiment to assess the impact of 30 years of tree planting by the nonprofit Friends of Trees on non-accidental, cardiovascular, lower-respiratory, and accidental mortality in Portland, Oregon (mortality data were provided by the Oregon Health Authority). We estimated autoregressive mixed models of Census-tract level mortality rate (deaths per 100,000 population) associated with trees planted, including a tract-level random effect. All models used data from the American Community Survey to control for year, race, education, income, and age. Each tree planted in the preceding 15 years was associated with significant reductions in non-accidental (-0.21, 95 % CI: -0.30, -0.12) and cardiovascular mortality (-0.066, 95 % CI: -0.11, -0.027). Furthermore, the dose-response association between tree planting and non-accidental mortality increased in magnitude as trees aged and grew. Each tree planted in the preceding 1-5 years was associated with a reduction in mortality rate of -0.154 (95 % CI: -0.323, 0.0146), whereas each tree planted in the last 6-10 and 11-15 years was associated with a reduction in mortality rate of -0.262 (95 % CI: -0.413, -0.110) and -0.306 (95 % CI: -0.527, -0.0841) respectively. Using US EPA estimates of a value of a statistical life, we estimated that planting a tree in each of Portland's 140 Census tracts would generate $14.2 million in annual benefits (95 % CI: $8.0 million to $20.4 million). In contrast, the annual cost of maintaining 140 trees would be $2,716-$13,720.

Exploring the impacts of street-level greenspace on stroke and cardiovascular diseases in Chinese adults

In recent years, cardiovascular diseases (CVDs) have become the primary cause of death in the world. Existing studies have found that greenspace is important for the prevention of CVDs and stroke. However, since they only focus on large green infrastructure (e.g., urban parks) or the general greenspace (usually being evaluated through normalized difference vegetation index), little information exists regarding the association between street-level greenspace and CVDs (stroke). In this study, the CVDs and stroke data of participants were retrieved from the 33 Chinese Community Health Study. We measured participants' exposure to street-level greenspace exposure using street view images and machine learning technique. Multilevel logistic regressions were applied. While controlling for confounders, we found that higher level of street-level greenspace exposure was associated with lower CVDs prevalence. However, street-level greenspace exposure was associated with stroke prevalence only for females. The associations were stronger among females, younger adults, participants with educational attainment above high school, physically active participants and participants who were not overweight. None of the mediators (air pollution, physical exercise, and BMI) can explain the associations between street-level greenspace exposure and CVDs (stroke) prevalence. Our findings suggest that street-level vegetation should be increased to cope with the rapid growth of the CVDs burdens. Also, the differences between the effect of street-level trees and grasses should be noted before formulating specific urban planning policies.

Green space and cardiovascular disease: A systematic review with meta-analysis

Exposure to green space has been proposed to be beneficially associated with cardiovascular morbidity and mortality. Many studies have explored this topic, but the results remain conflicting. We aimed to evaluate the epidemiological evidence on this topic by performing a systematic review with meta-analysis. We searched PubMed, Web of Science and Embase for studies on the association between green space and cardiovascular disease (CVD) that were published till January 2022. Two authors independently performed study selection, data extraction, quality assessment, and risk of bias assessment. For studies providing detailed numeric data, we also conducted quantitative meta-analyses and calculated the pooled odd ratios (ORs) for associations between the most commonly used exposure estimate (normalized difference vegetative index [NDVI]) and five CVD events: CVD mortality, ischemic heart disease (IHD) mortality, cerebrovascular disease (CBVD) mortality, and stroke incidence/prevalence. Additional analyses were conducted to explore the geographical scale effects of NDVI. Publication bias tests were also conducted. Of the 6787 records identified, 53 studies were eligible for inclusion. These studies covered 18 countries and included data from more than 100 million persons. Meta-analyses showed that a 0.1 increase in NDVI was significantly associated with 2-3% lower odds of CVD mortality (OR: 0.97, 95% CI: 0.96-0.99), IHD mortality (OR: 0.98, 95% CI: 0.96-1.00), CBVD mortality (OR: 0.98, 95% CI: 0.97-1.00), and stroke incidence/prevalence (OR: 0.98, 95% CI: 0.96-0.99). There was no significant difference between the pooled estimates for different buffer sizes. No evidence of publication bias was detected. We provide strong and robust evidence for the beneficial effects of green space exposure on cardiovascular health. More prospective studies and mechanistic studies, especially that conducted in low- and middle-income countries, are merited to strengthen our conclusions.

Residential Exposure to Urban Trees and Medication Sales for Mood Disorders and Cardiovascular Disease in Brussels, Belgium: An Ecological Study

BACKGROUND

The available evidence for positive associations between urban trees and human health is mixed, partly because the assessment of exposure to trees is often imprecise because of, for instance, exclusion of trees in private areas and the lack of three-dimensional (3D) exposure indicators (e.g., crown volume).

OBJECTIVES

We aimed to quantify all trees and relevant 3D structural traits in Brussels (Belgium) and to investigate associations between the number of trees, tree traits, and sales of medication commonly prescribed for mood disorders and cardiovascular disease.

METHODS

We developed a workflow to automatically isolate all individual trees from airborne light detection and ranging (LiDAR) data collected in 2012. Trait data were subsequently extracted for 309,757 trees in 604 census tracts. We used the average annual age-standardized rate of medication sales in Brussels for the period 2006 to 2014, calculated from reimbursement information on medication prescribed to adults (19-64 years of age). The medication sales data were provided by sex at the census tract level. Generalized log-linear models were used to investigate associations between the number of trees, the crown volume, tree structural variation, and medication sales. Models were run separately for mood disorder and cardiovascular medication and for men and women. All models were adjusted for indicators of area-level socioeconomic status.

RESULTS

Single-factor models showed that higher stem densities and higher crown volumes are both associated with lower medication sales, but opposing associations emerged in multifactor models. Higher crown volume [an increase by one interquartile range (IQR) of 1.4×104 m³/ha] was associated with 34% lower mood disorder medication sales [women, β=-0.341 (95% CI: -0.379, -0.303); men, β=-0.340 (95% CI: -0.378, -0.303)] and with 21-25% lower cardiovascular medication sales [women, β=-0.214 (95% CI: -0.246, -0.182); men, β=-0.252 (95% CI: -0.285, -0.219)]. Conversely, a higher stem density (an increase by one IQR of 21.8 trees/ha) was associated with 28-32% higher mood disorder medication sales [women, β=0.322 (95% CI: 0.284, 0.361); men, β=0.281 (95% CI: 0.243, 0.319)] and with 20-24% higher cardiovascular medication sales [women, β=0.202 (95% CI: 0.169, 0.236); men, β=0.240 (95% CI: 0.206, 0.273)].

DISCUSSION

We found a trade-off between the number of trees and the crown volumes of those trees for human health benefits in an urban environment. Our results demonstrate that conserving large trees in urban environments may not only support conservation of biodiversity but also human health. https://doi.org/10.1289/EHP9924.

Greenspace, Inflammation, Cardiovascular Health, and Cancer: A Review and Conceptual Framework for Greenspace in Cardio-Oncology Research

Cardiovascular disease (CVD) is a leading cause of global morbidity and mortality. Cancer survivors have significantly elevated risk of poor cardiovascular (CV) health outcomes due to close co-morbid linkages and shared risk factors between CVD and cancer, as well as adverse effects of cancer treatment-related cardiotoxicity. CVD and cancer-related outcomes are exacerbated by increased risk of inflammation. Results from different pharmacological interventions aimed at reducing inflammation and risk of major adverse cardiovascular events (MACEs) have been largely mixed to date. Greenspaces have been shown to reduce inflammation and have been associated with CV health benefits, including reduced CVD behavioral risk factors and overall improvement in CV outcomes. Greenspace may, thus, serve to alleviate the CVD burden among cancer survivors. To understand pathways through which greenspace can prevent or reduce adverse CV outcomes among cancer survivors, we review the state of knowledge on associations among inflammation, CVD, cancer, and existing pharmacological interventions. We then discuss greenspace benefits for CV health from ecological to multilevel studies and a few existing experimental studies. Furthermore, we review the relationship between greenspace and inflammation, and we highlight forest bathing in Asian-based studies while presenting existing research gaps in the US literature. Then, we use the socioecological model of health to present an expanded conceptual framework to help fill this US literature gap. Lastly, we present a way forward, including implications for translational science and a brief discussion on necessities for virtual nature and/or exposure to nature images due to the increasing human-nature disconnect; we also offer guidance for greenspace research in cardio-oncology to improve CV health outcomes among cancer survivors.

Urban forest biodiversity and cardiovascular disease: Potential health benefits from California's street trees

Enhanced immune functioning in response to biodiversity may explain potential health benefits from exposure to green space. Using unique data on urban forest biodiversity at the zip code level for California measured from 2014 to 2019 we test whether greater diversity of street trees is associated with reduced death from cardiovascular disease. We find that urban forests with greater biodiversity measured via the Shannon Index at the genus level are associated with a lower mortality rate for heart disease and stroke. Our estimates imply that increasing the Shannon Index by one standard deviation (0.64) is associated with a decrease in the mortality rate of 21.4 per 100,000 individuals for heart disease or 13% and 7.7 per 100,000 individuals for stroke or 16%. Our estimates remain robust across several sensitivity checks. A policy simulation for tree planting in Los Angeles based on our estimates suggests that if these relationships were causal, investment in planting for a more biodiverse set of street trees would be a cost-effective way to reduce mortality related to cardiovascular disease in urban areas.

Green space exposure on mortality and cardiovascular outcomes in older adults: a systematic review and meta-analysis of observational studies

BACKGROUND

With the launch of the "Global Age-Friendly Cities project", increasing emphasis has been placed on the effects of green spaces on health in the elderly. The previous literature has shown that green spaces are beneficial to a range of health-related outcomes in adults. However, associations of greenness with mortality and cardiovascular outcomes are less certain, which may differ depending on the age class. This review aimed to synthesize current evidence from observational studies to assess relationships of green space exposure with mortality and cardiovascular outcomes in older individuals.

METHODS

Five databases were searched. Qualitative evaluation and meta-analyses of included studies were conducted. This review is registered with PROSPERO, CRD42020160366.

RESULTS

Of the 8,143 records identified, we finally included 22 studies. In a narrative systematic review, we observed that the majority of studies showed reductions in the risk of all-cause mortality and total cardiovascular disease. Further meta-analyses which included eight cohort studies, indicated that greater greenness exposure (per 0.1 unit increase of normalized difference vegetation index (NDVI)) was associated with a reduced risk of all-cause mortality (pooled hazard ratios (HR) (95% confidence interval (CI) = 0.99 (0.97, 1.00)) and stroke mortality (pooled HR (95% CI) = 0.77 (0.59, 1.00)) in older individuals.

CONCLUSIONS

This review supports increasing green space exposure in terms of the prevention of death and cardiovascular outcomes in older individuals. Effective measures to increase or preserve greenspaces should therefore be considered as important public health interventions.

The association between natural environments and childhood mental health and development: A systematic review and assessment of different exposure measurements

BACKGROUND

Several studies have assessed the relationship between exposure to natural environments (NEs) and childhood mental health and development. In most cases, a positive association has been found, but results are inconsistent, and the strength of association is unclear. This inconsistency may reflect the heterogeneity in measurements used to assess NE.

OBJECTIVES

This systematic review aims to identify the most common NE metrics used in childhood mental health and development research. Our second aim is to identify the metrics that are most consistently associated with health and assess the relative strength of association depending on type of NE exposure measurement, in terms of metric used (i.e., measurement technique, such as remote sensing), but also rate (i.e., spatial and temporal exposure).

METHODS

We used the PRISMA protocol to identify eligible studies, following a set of pre-defined inclusion criteria based on the PECOS strategy. A number of keywords were used for retrieving relevant articles from Medline, Embase, PsychINFO, and Web of Science databases between January 2000-November 2020. From these, we extracted data on type of NE measurement and relative association to a number of indicators of childhood mental health and development. We conducted a systematic assessment of quality and risk of bias in the included articles to evaluate the level of evidence. Case studies and qualitative studies were excluded.

RESULTS

After screening of title (283 studies included), abstract, and full article, 45 studies were included in our review. A majority of which were conducted in North America and Europe (n = 36; 80%). The majority of studies used land use or land covers (LULC, n = 24; 35%) to determine exposures to NEs. Other metrics included the normalized difference vegetation index (NDVI), expert measures (e.g., surveys of data collection done by experts), surveys (e.g., self-reported assessments), and use of NE (e.g., measures of a participant's use of NE such as through GPS tracts or parent reports). Rate was most commonly determined by buffer zones around residential addresses or postal codes. The most consistent association to health outcomes was found for buffers of 100 m, 250 m, 500 m, and within polygons boundaries (e.g., census tracts). Six health categories, academic achievement, prevalence of doctor diagnosed disorders, emotional and behavioral functioning, well-being, social functioning, and cognitive skills, were created post hoc. We found sufficient evidence between NDVI (Landsat) and emotional and behavioral well-being. Additionally, we found limited evidence between LULC datasets and academic achievement; use of NE, parent/guardian reported greenness, and expert measures of greenness and emotional and behavioral functioning; and use of NE and social functioning.

DISCUSSION

This review demonstrates that several NE measurements must be evaluated further before sufficient evidence for a potential association between distinct NE exposure metrics and childhood mental health and development can be established. Further, we suggest increased coordination between research efforts, for example, by replication of studies and comparing different NE measurements systematically, so that effect sizes can be confirmed for various health outcomes. Finally, we recommend implementing research designs that assess underlying pathways of nature-health relations and utilize measurement techniques that adequately assess exposure, access, use, and perception of NEs in order to contribute to a better understanding of health impacts of surrounding natural environments.

Associations between Nature Exposure and Health: A Review of the Evidence

There is extensive empirical literature on the association between exposure to nature and health. In this narrative review, we discuss the strength of evidence from recent (i.e., the last decade) experimental and observational studies on nature exposure and health, highlighting research on children and youth where possible. We found evidence for associations between nature exposure and improved cognitive function, brain activity, blood pressure, mental health, physical activity, and sleep. Results from experimental studies provide evidence of protective effects of exposure to natural environments on mental health outcomes and cognitive function. Cross-sectional observational studies provide evidence of positive associations between nature exposure and increased levels of physical activity and decreased risk of cardiovascular disease, and longitudinal observational studies are beginning to assess long-term effects of nature exposure on depression, anxiety, cognitive function, and chronic disease. Limitations of current knowledge include inconsistent measures of exposure to nature, the impacts of the type and quality of green space, and health effects of duration and frequency of exposure. Future directions include incorporation of more rigorous study designs, investigation of the underlying mechanisms of the association between green space and health, advancement of exposure assessment, and evaluation of sensitive periods in the early life-course.

Neighborhood Characteristics and Cardiovascular Biomarkers in Middle-Aged and Older Adults: the Baltimore Memory Study

Neighborhood greenness has been linked to better cardiovascular health, but little is known about its association with biomarkers related to cardiovascular risk. Adverse neighborhood conditions, such as disorder and socioeconomic disadvantage, are associated with higher cardiovascular biomarker levels, but these relationships may differ in neighborhoods with more greenness. This study evaluated cross-sectional associations of validated measures of neighborhood greenness, disorder, and socioeconomic disadvantage with cardiovascular biomarkers in middle-aged and older adults living in Baltimore City. The sample included 500 adults, aged 57-79 years, enrolled in the Baltimore Memory Study and living in Baltimore City during 2009-2010. Multi-level log-gamma regressions examined associations between the three neighborhood characteristics and seven cardiovascular biomarkers. Models additionally evaluated the effect modification by neighborhood greenness on associations of neighborhood disorder and socioeconomic disadvantage with the biomarkers. Adjusting for covariates and neighborhood greenness, greater neighborhood disorder was associated with higher C-reactive protein (exp β = 1.21, SE = 0.11, p = 0.035) and serum amyloid A (exp β = 1.28, SE = 0.12, p = 0.008), while greater neighborhood socioeconomic disadvantage was associated with higher tumor necrosis factor alpha (exp β = 1.24, SE = 0.12, p = 0.019). Higher neighborhood greenness was associated with lower soluble vascular cell adhesion molecule-1, accounting for disorder (exp β = 0.70, SE = 0.10, p = 0.010) and socioeconomic disadvantage (exp β = 0.73, SE = 0.10, p = 0.025). There was no evidence of effect modification among neighborhood characteristics. The findings suggest that neighborhood effects on cardiovascular health may be mediated through cardiovascular biomarker levels, and that socioeconomic disadvantage, disorder, and greenness may each be important features of neighborhoods.

Identification and Estimation of Causal Effects Using a Negative-Control Exposure in Time-Series Studies With Applications to Environmental Epidemiology

The initial aim of environmental epidemiology is to estimate the causal effects of environmental exposures on health outcomes. However, due to lack of enough covariates in most environmental data sets, current methods without enough adjustments for confounders inevitably lead to residual confounding. We propose a negative-control exposure based on a time-series studies (NCE-TS) model to effectively eliminate unobserved confounders using an after-outcome exposure as a negative-control exposure. We show that the causal effect is identifiable and can be estimated by the NCE-TS for continuous and categorical outcomes. Simulation studies indicate unbiased estimation by the NCE-TS model. The potential of NCE-TS is illustrated by 2 challenging applications: We found that living in areas with higher levels of surrounding greenness over 6 months was associated with less risk of stroke-specific mortality, based on the Shandong Ecological Health Cohort during January 1, 2010, to December 31, 2018. In addition, we found that the widely established negative association between temperature and cancer risks was actually caused by numbers of unobserved confounders, according to the Global Open Database from 2003-2012. The proposed NCE-TS model is implemented in an R package (R Foundation for Statistical Computing, Vienna, Austria) called NCETS, freely available on GitHub.

Remote sensing metrics to assess exposure to residential greenness in epidemiological studies: A population case study from the Eastern Mediterranean

INTRODUCTION/AIMS

Application of remote sensing-based metrics of exposure to vegetation in epidemiological studies of residential greenness is typically limited to several standard products. The Normalized Difference Vegetation Index (NDVI) is the most widely used, but its precision varies with vegetation density and soil color/moisture. In areas with heterogeneous vegetation cover, the Soil-adjusted Vegetation Index (SAVI) corrects for soil brightness. Linear Spectral Unmixing (LSU), measures the relative contribution of different land covers, and estimates percent of each over a unit area. We compared the precision of NDVI, SAVI and LSU for quantifying residential greenness in areas with high spatial heterogeneity in vegetation cover.

METHODS

NDVI, SAVI, and LSU in a 300 m radius surrounding homes of 3,188 cardiac patients living in Israel (Eastern Mediterranean) were derived from Landsat 30 m spatial resolution imagery. Metrics were compared to assess shifts in exposure quartiles and differences in vegetation detection as a function of overall greenness, climatic zones, and population density, using NDVI as the reference method.

RESULTS

For the entire population, the dispersion (SD) of the vegetation values detected was 60% higher when greenness was measured using LSU compared to NDVI: mean (SD) NDVI: 0.17 (0.05), LSU (%): 0.23 (0.08), SAVI: 0.12 (0.03). Importantly, with an increase in population density, the sensitivity of LSU, compared to NDVI, doubled: There was a 95% difference between the LSU and NDVI interquartile range in the highest population density quartile vs 47% in the lowest quartile. Compared to NDVI, exposures estimated by LSU resulted in 21% of patients changing exposure quartiles. In urban areas, the shift in exposure quartile depended on land cover characteristics. An upward shift occurred in dense urban areas, while no shift occurred in high and low vegetated urban areas.

CONCLUSIONS

LSU was shown to outperform the commonly used NDVI in terms of accuracy and variability, especially in dense urban areas. Therefore, LSU potentially improves exposure assessment precision, implying reduced exposure misclassification.

Association Between Residential Greenness, Cardiometabolic Disorders, and Cardiovascular Disease Among Adults in China

IMPORTANCE

Living in areas with more vegetation (referred to as residential greenness) may be associated with cardiovascular disease (CVD), but little data are available from low- and middle-income countries. In addition, it remains unclear whether the presence of cardiometabolic disorders modifies or mediates the association between residential greenness and CVD.

OBJECTIVE

To evaluate the associations between residential greenness, cardiometabolic disorders, and CVD prevalence among adults in China.

DESIGN, SETTING, AND PARTICIPANTS

This analysis was performed as part of the 33 Communities Chinese Health Study, a large population-based cross-sectional study that was conducted in 33 communities (ranging from 0.25-0.64 km2) in 3 cities within the Liaoning province of northeastern China between April 1 and December 31, 2009. Participants included adults aged 18 to 74 years who had resided in the study area for 5 years or more. Greenness levels surrounding each participant's residential community were assessed using the normalized difference vegetation index and the soil-adjusted vegetation index from 2010. Lifetime CVD status (including myocardial infarction, heart failure, coronary heart disease, cerebral thrombosis, cerebral hemorrhage, cerebral embolism, and subarachnoid hemorrhage) was defined as a self-report of a physician diagnosis of CVD at the time of the survey. Cardiometabolic disorders, including hypertension, diabetes, dyslipidemia, and overweight or obese status, were measured and defined clinically. Generalized linear mixed models were used to evaluate the association between residential greenness levels and CVD prevalence. A 3-way decomposition method was used to explore whether the presence of cardiometabolic disorders mediated or modified the association between residential greenness and CVD. Data were analyzed from October 10 to May 30, 2020.

MAIN OUTCOMES AND MEASURES

Lifetime CVD status, the presence of cardiometabolic disorders, and residential greenness level.

RESULTS

Among 24 845 participants, the mean (SD) age was 45.6 (13.3) years, and 12 661 participants (51.0%) were men. A total of 1006 participants (4.1%) reported having a diagnosis of CVD. An interquartile range (1-IQR) increase in the normalized difference vegetation index within 500 m of a community was associated with a 27% lower likelihood (odds ratio [OR], 0.73; 95% CI, 0.65-0.83; P < .001) of CVD prevalence, and an IQR increase in the soil-adjusted vegetation index within 500 m of a community was associated with a 26% lower likelihood (OR, 0.74; 95% CI, 0.66-0.84; P < .001) of CVD prevalence. The presence of cardiometabolic disorders was found to mediate the association between residential greenness and CVD, with mediation effects of 4.5% for hypertension, 4.1% for type 2 diabetes, 3.1% for overweight or obese status, 12.7% for hypercholesterolemia, 8.7% for hypertriglyceridemia, and 11.1% for high low-density lipoprotein cholesterol levels.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, higher residential greenness levels were associated with lower CVD prevalence, and this association may be partially mediated by the presence of cardiometabolic disorders. Further studies, preferably longitudinal, are warranted to confirm these findings.

Planning for Supportive Green Spaces in the Winter City of China: Linking Exercise of Elderly Residents and Exercise Prescription for Cardiovascular Health

The elderly population have a high incidence of cardiovascular disease and are the main users of green spaces, such as city parks. Creating supportive green spaces for exercise for the elderly is of great significance to promote their cardiovascular health. The winter cities have a severely cold climate and high incidence of cardiovascular disease, while the elderly, especially those with cardiovascular disease, face more challenges when participating in exercise in the green spaces. In the context of the winter cities, the kinds of exercise the elderly participate in are more conducive to their cardiovascular health, and determining the factors of the green spaces that are supportive for exercise for cardiovascular health in the winter are of particular interest. Taking Harbin, a typical winter city in China, as an example, this study aims to identify the exercise characteristics of elderly residents in the green spaces in winter, to link them with the principles and contents of exercise prescription for cardiovascular health, to identify the deficient factors of the green spaces in supporting exercise for cardiovascular health, and to put forward optimization design implications. Mixed qualitative methods including interviews, a questionnaire, and field observation were used to identify special behavioral characteristics and spatial factors involving winter exercise in the green spaces among the elderly. The results showed that: (1) about 42.4% of the participants had a gap with the principles of exercise prescription for cardiovascular health. Their exercise items were generally consistent with the principle of low-intensity exercise, but some of them had the problems regarding early exercise time and insufficient exercise duration and frequency. (2) Insufficient supportive factors of the green spaces mainly included facilities allocation, comfort, safety, accessibility, and air quality. Facilities allocation involved walking paths, rehabilitation facilities, auxiliary facilities, and guidance facilities; comfort involved sunlight conditions of the exercise areas; safety involved slippery roads and sites with ice and snow and medical accidents; accessibility involved the proximity, the safety of connecting roads, and the movement of the elderly; air quality involved the planting of evergreen trees. Accordingly, the design implications were given in order to bridge the supportive gap of the green spaces for exercise for cardiovascular health in the elderly population.

Residential Greenness and Cardiovascular Disease Incidence, Readmission, and Mortality

BACKGROUND

Living in greener areas of cities was linked to increased physical activity levels, improved mental well-being, and lowered harmful environmental exposures, all of which may affect human health. However, whether living in greener areas may be associated with lower risk of cardiovascular disease incidence, progression, and premature mortality is unclear.

OBJECTIVES

We conducted a cohort study to examine the associations between residential green spaces and the incidence of acute myocardial infarction (AMI) and heart failure (HF), post-AMI and HF hospital readmissions, and mortality.

METHODS

We simultaneously followed four large population-based cohorts in Ontario, Canada, including the entire adult population, adults free of AMI and HF, and survivors of AMI or HF from 2000 to 2014. We estimated residential exposure to green spaces using satellite-derived observations and ascertained health outcomes using validated disease registries. We estimated the associations using spatial random-effects Cox proportional hazards models. We conducted various sensitivity analyses, including further adjusting for property values and performing exploratory mediation analysis.

RESULTS

Each interquartile range increase in residential greenness was associated with a 7% [95% confidence interval (CI): 4%, 9%] decrease in incident AMI and a 6% (95% CI: 4%, 7%) decrease in incident HF. Residential greenness was linked to a ∼10% decrease in cardiovascular mortality in both adults free of AMI and HF and the entire adult population. These associations remained consistent in sensitivity analyses and were accentuated among younger adults. Additionally, we estimated that the decreases in AMI and HF incidence associated with residential greenness explained ∼53% of the protective association between residential greenness and cardiovascular mortality. Conversely, residential greenness was not associated with any delay in readmission or mortality among AMI and HF patients.

CONCLUSIONS

Living in urban areas with more green spaces was associated with improved cardiovascular health in people free of AMI and HF but not among individuals who have already developed these conditions. https://doi.org/10.1289/EHP6161.

Different types of urban natural environments influence various dimensions of self-reported health

BACKGROUND

Growing evidence suggests health benefits of natural environments. Yet, the effects of different types of natural environments (vegetation and water features) and forms of human-nature contact (access versus exposure) remain relatively unexplored.

METHODS

A cross-sectional observational survey was used to analyse the relationship between both access and exposure to different types of urban natural environments and health outcomes in Metro Vancouver, Canada. Data for health outcomes (self-reported general health, mental health, and common mental disorders) and key confounders were obtained from the 2013-2014 Canadian Community Health Survey. Natural environments were quantified using local land use and land cover data, and linked to survey respondents by six-digit postal code. Access was defined as living within 300 m of a public greenspace (≥ 1 hectare) and exposure as the percentage of different land cover types within multiple buffer distances of postal code centroids. Separate logistic regression models were used to estimate the associations of the access and exposure metrics with the three health outcomes.

RESULTS

Exposure to water within 1,000 m buffers was associated with a reduced odds of reporting poor general health (OR = 0.982, 95% CI = 0.965, 0.999). A similar association was found for exposure to shrub and grass-herb vegetation types for reported mental health and common mental disorder, respectively (OR = 0.741, 95% CI = 0.576, 0.953 for shrubs in 250 m; OR = 0.737, 95% CI = 0.577, 0.942 for shrubs in 500 m; OR = 0.731, 95% CI = 0.570, 0.938 for shrubs in 1,000 m; OR = 0.980, 95% CI = 0.965, 0.995 for grass-herbs in 250 m). Neither access to public greenspace nor aggregated greenspace exposure were associated with self-reported health. Results from stratified analyses suggest that observed associations between human-nature contact and self-reported health differ according to gender.

CONCLUSIONS

Results suggest that type of natural environment should be considered in future research studying the health-promoting aspects of natural environments, and that positive health effects may be more consistent for daily life exposure than for access to public greenspace.

Urban Trees and Human Health: A Scoping Review

The urban forest is a green infrastructure system that delivers multiple environmental, economic, social and health services, and functions in cities. Environmental benefits of urban trees are well understood, but no review to date has examined how urban trees affect human health. This review provides a comprehensive summary of existing literature on the health impacts of urban trees that can inform future research, policy, and nature-based public health interventions. A systematic search used keywords representing human health, environmental health, and urban forestry. Following screening and appraisal of several thousand articles, 201 studies were conceptually sorted into a three-part framework. Reducing Harm, representing 41% of studies, includes topics such as air pollution, ultraviolet radiation, heat exposure, and pollen. Restoring Capacities, at 31%, includes attention restoration, mental health, stress reduction, and clinical outcomes. Building Capacities, at 28%, includes topics such as birth outcomes, active living, and weight status. The studies that were reviewed show substantial heterogeneity in purpose and method yet indicate important health outcomes associated with people’s exposure to trees. This review will help inform future research and practice, and demonstrates why urban forest planning and management should strategically promote trees as a social determinant of public health.

Landscape Planning for an Agricultural Research Center: A Research-by-Design Case Study in Chiang Mai, Thailand

Effective planning at the landscape scale is a difficult but crucial task. Modern landscape planning requires economic success, ecological resilience, and environmental justice. Thus, planners and designers must learn to use a deliberative approach in planning: an approach in which decisions are made with the common understanding of stakeholders. This notwithstanding, there is a lack of localized and site-specific design examples for deliberative planning. One of the lacking examples is agricultural research station, which is unique because it balances economic, academic, and public uses. This study used a Research-by-Design Method to explore deliberative planning for an agricultural research station in Chiang Mai, Thailand. Field surveys, interviews, and archival search were conducted for database. Design decisions were delivered via linear-combination suitability analysis. We found that the site was viewed differently by different sets of users. The basic and safety infrastructure was the top priority, and clear direction of governance was crucial to move the site forward in the future. This study was one of the first recorded attempts to design an agricultural research center via the Research-by-Design process. The method and results of the research contribute to the growing body of evidence to support the need of evidence-based design and planning for all sites.

Greenness, mortality and mental health prescription rates in urban Scotland - a population level, observational study

BACKGROUND: Recent studies have shown an association between vegetation around dwellings and mortality, with mental health as a possible mediator.

OBJECTIVES: Examine whether there is an association between greenness and mortality or greenness and the proportion of the population being prescribed drugs for anxiety, depression or psychosis in urban areas of Scotland.

METHODS: Two greenness maps were prepared based on Landsat 8 Normalised Difference Vegetation Index data from 2013 to 2016, one for summer and one for winter. Greenness was sampled from these maps around each of 91,357 urban postcodes. The greenness data was averaged by 4,883 urban Data Zones covering 71% of the Scottish population and compared with mortality and prescription rate data from the Scottish Index of Multiple Deprivation.

RESULTS: The areas least green in the summer were found to have higher mortality rates but no association was found between mortality and winter-greenness. The largest relative differences of mortality were around 9%. High levels of summer-greenness were associated with an increase in mental health prescription rates but areas with the highest differences between summer and winter-greenness had lower prescription rates than other areas. The largest relative difference in prescription rate was 17%. All models controlled for overall deprivation. It is hypothesised that the year round greenness of mown grass is associated with increased mental health prescriptions and obscures the benefits of other kinds of vegetation on both mortality and mental health.

DISCUSSION: There is an association between greenness and mortality and greenness and mental health. The association is both statistically significant and large enough to be of importance for policy making. Higher levels of non mown grass vegetation may be preferable for human wellbeing but more detailed understanding of the diversity of plant life in urban areas and how people related to it is required to make more specific recommendations.

Screening for Park Access during a Primary Care Social Determinants Screen

While there is evidence that access to nature and parks benefits pediatric health, it is unclear how low-income families living in an urban center acknowledge or prioritize access to parks. Methods: We conducted a study about access to parks by pediatric patients in a health system serving low-income families. Adult caregivers of pediatric patients completed a survey to identify and prioritize unmet social and economic needs, including access to parks. Univariate and multivariate analyses were conducted to explore associations between lack of access to parks and sociodemographic variables. We also explored the extent to which access to parks competed with other needs. Results: The survey was completed by 890 caregivers; 151 (17%) identified “access to green spaces/parks/playgrounds” as an unmet need, compared to 397 (45%) who endorsed “running out of food before you had money or food stamps to buy more”. Being at or below the poverty line doubled the odds (Odds ratio 1.96, 95% CI 1.16–3.31) of lacking access to a park (reference group: above the poverty line), and lacking a high school degree nearly doubled the odds. Thirty-three of the 151 (22%) caregivers who identified access to parks as an unmet need prioritized it as one of three top unmet needs. Families who faced competing needs of housing, food, and employment insecurity were less likely to prioritize park access (p < 0.001). Conclusion: Clinical interventions to increase park access would benefit from an understanding of the social and economic adversity faced by patients.

Residential green space, air pollution, socioeconomic deprivation and cardiovascular medication sales in Belgium: A nationwide ecological study

Green space may improve cardiovascular (CV) health, for example by promoting physical activity and by reducing air pollution, noise and heat. Socioeconomic and environmental factors may modify the health effects of green space. We examined the association between residential green space and reimbursed CV medication sales in Belgium between 2006 and 2014, adjusting for socioeconomic deprivation and air pollution. We analyzed data for 11,575 census tracts using structural equation models for the entire country and for the administrative regions. Latent variables for green space, air pollution and socioeconomic deprivation were used as predictors of CV medication sales and were estimated from the number of patches of forest, census tract relative forest cover and relative forest cover within a 600 m buffer around the census tract; annual mean concentrations of PM_2.5, BC and NO₂; and percentages of inhabitants that were foreign-born from lower- and mid-income countries, unemployed or had no higher education. A direct association between socioeconomic deprivation and CV medication sales [parameter estimate (95% CI): 0.26 (0.25; 0.28)] and inverse associations between CV medication sales and green space [-0.71 (-0.80; -0.61)] and air pollution [-1.62 (-1.69; -0.61)] were observed. In the regional models, the association between green space and CV medication sales was stronger in the region with relatively low green space cover (Flemish Region, standardized estimate -0.16) than in the region with high green space cover (Walloon Region, -0.10). In the highly urbanized Brussels Capital Region the association tended towards the null. In all regions, the associations between CV medication sales and socioeconomic deprivation were direct and more prominent. Our results suggest that there may be an inverse association between green space and CV medication sales, but socioeconomic deprivation was always the strongest predictor of CV medication sales.

Residential urban tree canopy is associated with decreased mortality during tuberculosis treatment in California

Trees can sequester air pollutants, and air pollution is associated with poor tuberculosis outcomes. However, the health impacts of urban trees on tuberculosis patients are unknown. To elucidate the effects of urban tree canopy on mortality during tuberculosis treatment, we evaluated patients diagnosed with active tuberculosis in California from 2000 through 2012, obtaining patient data from the California tuberculosis registry. Our primary outcome was all-cause mortality during tuberculosis treatment. We determined percent tree cover using 1 mresolution color infrared orthoimagery categorized into land cover classes, then linked tree cover to four circular buffer zones of 50-300 m radii around patient residential addresses. We used the Kaplan-Meier method to estimate survival probabilities and Cox regression models to determine mortality hazard ratios, adjusting for demographic, socioeconomic, and clinical covariates. Our cohort included 33,962 tuberculosis patients of median age 47, 59% male, 51% unemployed, and 4.9% HIV positive. Tuberculosis was microbiologically confirmed in 79%, and 1.17% were multi-drug resistant (MDR). Median tree cover was 7.9% (50 m buffer). Patients were followed for 23,280 person-years with 2370 deaths during tuberculosis treatment resulting in a crude mortality rate of 1018 deaths per 10,000 person-years. Increasing tree cover quintiles were associated with decreasing mortality risk during tuberculosis treatment in all buffers, and the magnitude of association decreased incrementally with increasing buffer radius: In the 50 m buffer, patients living in neighborhoods with the highest quintile tree cover experienced a 22% reduction in mortality (HR 0.78, 95%CI 0.68-0.90) compared to those living in lowest quintile tree cover; whereas for 100, 200, and 300 m buffers, a 21%, 13%, and 11% mortality risk reduction was evident. In conclusion, urban tree canopy was associated with decreased mortality during tuberculosis treatment even after adjusting for multiple demographic, socioeconomic, and clinical factors, suggesting that trees might play a role in improving tuberculosis outcomes.

Spaceship Earth Revisited: The Co-Benefits of Overcoming Biological Extinction of Experience at the Level of Person, Place and Planet

Extensive research underscores that we interpret the world through metaphors; moreover, common metaphors are a useful means to enhance the pursuit of personal and collective goals. In the context of planetary health—defined as the interdependent vitality of all natural and anthropogenic ecosystems (social, political and otherwise)—one enduring metaphor can be found in the concept of “Spaceship Earth”. Although not without criticism, the term “Spaceship Earth” has been useful to highlight both resource limitations and the beauty and fragility of delicate ecosystems that sustain life. Rene Dubos, who helped popularize the term, underscored the need for an exposome perspective, one that examines the total accumulated environmental exposures (both detrimental and beneficial) that predict the biological responses of the “total organism to the total environment” over time. In other words, how large-scale environmental changes affect us all personally, albeit in individualized ways. This commentary focuses the ways in which microbes, as an essential part of all ecosystems, provide a vital link between personal and planetary systems, and mediate the biopsychosocial aspects of our individualized experience—and thus health—over our life course journey. A more fine-grained understanding of these dynamics and our power to change them, personally and collectively, lies at the core of restoring “ecosystems balance” for person, place and planet. In particular, restoring human connectedness to the natural world, sense of community and shared purpose must occur in tandem with technological solutions, and will enhance individual empowerment for personal well-being, as well as our collective potential to overcome our grand challenges. Such knowledge can help shape the use of metaphor and re-imagine solutions and novel ways for restoration or rewilding of ecosystems, and the values, behaviors and attitudes to light the path toward exiting the Anthropocene.

Relationship of Neighborhood Greenness to Heart Disease in 249 405 US Medicare Beneficiaries

Background Nature 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 Results The 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. Conclusions Neighborhood 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.

Green space associations with mental health and cognitive function: Results from the Quebec CARTaGENE cohort

Supplemental Digital Content is available in the text.

Urban green space may be important to mental health, but the association between long-term green space exposures and depression, anxiety, and cognitive function in adults remains unknown.

Preventive Medicine for Person, Place, and Planet: Revisiting the Concept of High-Level Wellness in the Planetary Health Paradigm

Experts in preventive medicine and public health have long-since recognized that health is more than the absence of disease, and that each person in the ‘waiting room’ and beyond manifests the social/political/economic ecosystems that are part of their total lived experience. The term planetary health—denoting the interconnections between the health of person and place at all scales—emerged from the environmental and preventive health movements of the 1970–1980s. Roused by the 2015 Lancet Commission on Planetary Health report, the term has more recently penetrated mainstream academic and medical discourse. Here, we discuss the relevance of planetary health in the era of personalized medicine, gross environmental concerns, and a crisis of non-communicable diseases. We frame our discourse around high-level wellness—a concept of vitality defined by Halbert L. Dunn (1896–1975); high-level wellness was defined as an integrated method of functioning which is oriented toward maximizing the potential of individuals within the total lived environment. Dunn maintained that high-level wellness is also applicable to organizations, communities, nations, and humankind as a whole—stating further that global high-level wellness is a product of the vitality and sustainability of the Earth’s natural systems. He called for a universal philosophy of living. Researchers and healthcare providers who focus on lifestyle and environmental aspects of health—and understand barriers such as authoritarianism and social dominance orientation—are fundamental to maintaining trans-generational vitality at scales of person, place, and planet.

Communicating the benefits of population health interventions: The health effects can be on par with those of medication

How can we communicate to the public that population level health interventions are effective at improving health? Perhaps the most familiar "currency" of effect is that which can be brought about via medication. Comparisons of effect sizes may be effective ways of communicating the benefits of population health interventions if they are seen and understood in the same way that medications are. We developed a series of comparisons to communicate benefits of population health interventions in terms of similar gains to be obtained from statins, metformin and antihypertensive medications for prevention of cardiovascular events, type 2 diabetes, obesity and hypertension. A purposive search identified evidence of population health intervention-related benefits. This evidence ranged from meta-analyses of RCTs to that from observational cohort studies. Population health interventions included implementation of national smoke free legislation, enhanced neighbourhood walkability, increased opportunities for active travel and protection of urban green space. In some cases, the benefits of population health interventions were found to be equivalent to, or even outweighed those of the medications to which they were compared. For example, RCT-based evidence suggested that exercise taken with a view of a green space was associated with 12 mmHg and 6 mmHg reductions in systolic and diastolic blood pressure, respectively, which was at least on par with the reductions associated with antihypertensive medications. Future work will test the effectiveness of these comparisons for increasing the familiarity, credibility and acceptability of population health interventions and, in particular, examine the importance of communicating putative mechanisms and potential co-benefits.

The importance of the exposome and allostatic load in the planetary health paradigm

In 1980, Jonas Salk (1914-1995) encouraged professionals in anthropology and related disciplines to consider the interconnections between "planetary health," sociocultural changes associated with technological advances, and the biology of human health. The concept of planetary health emphasizes that human health is intricately connected to the health of natural systems within the Earth's biosphere; experts in physiological anthropology have illuminated some of the mechanisms by which experiences in natural environments (or the built environment) can promote or detract from health. For example, shinrin-yoku and related research (which first emerged from Japan in the 1990s) helped set in motion international studies that have since examined physiological responses to time spent in natural and/or urban environments. However, in order to advance such findings into planetary health discourse, it will be necessary to further understand how these biological responses (inflammation and the collective of allostatic load) are connected to psychological constructs such as nature relatedness, and pro-social/environmental attitudes and behaviors. The exposome refers to total environmental exposures-detrimental and beneficial-that can help predict biological responses of the organism to environment over time. Advances in "omics" techniques-metagenomics, proteomics, metabolomics-and systems biology are allowing researchers to gain unprecedented insight into the physiological ramifications of human behavior. Objective markers of stress physiology and microbiome research may help illuminate the personal, public, and planetary health consequences of "extinction of experience." At the same time, planetary health as an emerging multidisciplinary concept will be strengthened by input from the perspectives of physiological anthropology.

Is All Urban Green Space the Same? A Comparison of the Health Benefits of Trees and Grass in New York City

Living near vegetation, often called “green space” or “greenness”, has been associated with numerous health benefits. We hypothesized that the two key components of urban vegetation, trees and grass, may differentially affect health. We estimated the association between near-residence trees, grass, and total vegetation (from the 2010 High Resolution Land Cover dataset for New York City (NYC)) with self-reported health from a survey of NYC adults (n = 1281). We found higher reporting of “very good” or “excellent” health for respondents with the highest, compared to the lowest, quartiles of tree (RR = 1.23, 95% CI = 1.06–1.44) but not grass density (relative risk (RR) = 1.00, 95% CI = 0.86–1.17) within 1000 m buffers, adjusting for pertinent confounders. Significant positive associations between trees and self-reported health remained after adjustment for grass, whereas associations with grass remained non-significant. Adjustment for air pollutants increased beneficial associations between trees and self-reported health; adjustment for parks only partially attenuated these effects. Results were null or negative using a 300 m buffer. Findings imply that higher exposure to vegetation, particularly trees outside of parks, may be associated with better health. If replicated, this may suggest that urban street tree planting may improve population health.

Eco-Health linkages: assessing the role of ecosystem goods and services on human health using causal criteria analysis

OBJECTIVES

In the last decade, we saw an upsurge of studies evaluating the role of ecosystem goods and services (EGS) on human health (Eco-Health). Most of this work consists of observational research of intermediate processes and few address the full pathways from ecosystem to EGS to human health, limiting our ability to assess causality.

METHODS

We conducted a causal criteria analysis of Eco-Health literature using Eco-Evidence, a software tool that helps evaluate evidence of cause-effect relationships. We focus on the context of green spaces providing "buffering" EGS that may influence disease.

RESULTS

We found support for a causal linkage between green spaces and all of the EGS tested, and sufficient evidence linking EGS to gastro intestinal disease and heat morbidities. Inconsistencies were found when assessing the link between EGS to cardiovascular and respiratory diseases. Few studies directly link green spaces to health. Those that do, support a connection to cardiovascular disease, and heat morbidities, but provide inconsistent evidence regarding respiratory illness.

CONCLUSIONS

Our results help establish an agenda to shape future Eco-Health research and define priorities for managing green spaces to provide human health benefits.

Nature Contact and Human Health: A Research Agenda

BACKGROUND

At a time of increasing disconnectedness from nature, scientific interest in the potential health benefits of nature contact has grown. Research in recent decades has yielded substantial evidence, but large gaps remain in our understanding.

OBJECTIVES

We propose a research agenda on nature contact and health, identifying principal domains of research and key questions that, if answered, would provide the basis for evidence-based public health interventions.

DISCUSSION

We identify research questions in seven domains: a) mechanistic biomedical studies; b) exposure science; c) epidemiology of health benefits; d) diversity and equity considerations; e) technological nature; f) economic and policy studies; and g) implementation science.

CONCLUSIONS

Nature contact may offer a range of human health benefits. Although much evidence is already available, much remains unknown. A robust research effort, guided by a focus on key unanswered questions, has the potential to yield high-impact, consequential public health insights. https://doi.org/10.1289/EHP1663.

Transforming Life: A Broad View of the Developmental Origins of Health and Disease Concept from an Ecological Justice Perspective

The influential scientist Rene J. Dubos (1901–1982) conducted groundbreaking studies concerning early-life environmental exposures (e.g., diet, social interactions, commensal microbiota, housing conditions) and adult disease. However, Dubos looked beyond the scientific focus on disease, arguing that “mere survival is not enough”. He defined mental health as fulfilling human potential, and expressed concerns about urbanization occurring in tandem with disappearing access to natural environments (and elements found within them); thus modernity could interfere with health via “missing exposures”. With the advantage of emerging research involving green space, the microbiome, biodiversity and positive psychology, we discuss ecological justice in the dysbiosphere and the forces—financial inequity, voids in public policy, marketing and otherwise—that interfere with the fundamental rights of children to thrive in a healthy urban ecosystem and learn respect for the natural environment. We emphasize health within the developmental origins of health and disease (DOHaD) rubric and suggest that greater focus on positive exposures might uncover mechanisms of resiliency that contribute to maximizing human potential. We will entrain our perspective to socioeconomic disadvantage in developed nations and what we have described as “grey space”; this is a mental as much as a physical environment, a space that serves to insidiously reinforce unhealthy behavior, compromise positive psychological outlook and, ultimately, trans-generational health. It is a dwelling place that cannot be fixed with encephalobiotics or the drug-class known as psychobiotics.

Residential greenness and blood lipids in children: A longitudinal analysis in GINIplus and LISAplus

INTRODUCTION

There is some evidence of decreased cardiovascular disease (CVD) mortality and morbidity among adults residing in greener places. Among others, blood lipids are well established risk factors for CVD. In our previous study, we observed the inverse association between greenness and blood pressure in 10-year-old children. In the current study, we investigated whether there is also a link between residential greenness and blood lipids in 10- and 15-year-old children.

METHODS

Complete data on blood lipids (total cholesterol, HDL, LDL and triglyceride), residential greenness (NDVI in 100-m, 300- and 500-m buffers around residences) and confounders were available for 1,552 participants at 10 and 15 years of age, residing in two study areas of two German birth cohorts - GINIplus and LISAplus. Longitudinal associations between NDVI and blood lipids were assessed by generalized estimation equations.

RESULTS

No associations were observed between residential greenness in any of the chosen buffers and blood lipids in children (e.g., change in blood lipids per interquartile increase in NDVI in 100-m buffer for total cholesterol and LDL: means ratio=1.00 (95% confidence interval: 0.99-1.01), for triglyceride: 0.98 (0.96-1.00)). No area- or sex-varying effects were evident. Change of the residence between 10 and 15 years also did not yield any consistent associations.

CONCLUSIONS

There is no evidence of an association between greenness and blood lipids in 10- and 15-years old children.

Biodiversity, the Human Microbiome and Mental Health: Moving toward a New Clinical Ecology for the 21st Century?

Advances in research concerning the brain-related influences of the microbiome have been paradigm shifting, although at an early stage, clinical research involving beneficial microbes lends credence to the notion that the microbiome may be an important target in supporting mental health (defined here along the continuum between quality of life and the criteria for specific disorders). Through metagenomics, proteomics, metabolomics, and systems biology, a new emphasis to personalized medicine is on the horizon. Humans can now be viewed as multispecies organisms operating within an ecological theatre; it is important that clinicians increasingly see their patients in this context. Historically marginalized ecological aspects of health are destined to become an important consideration in the new frontiers of practicing medicine with the microbiome in mind. Emerging evidence indicates that macrobiodiversity in the external environment can influence mental well-being. Local biodiversity may also drive differences in human-associated microbiota; microbial diversity as a product of external biodiversity may have far-reaching effects on immune function and mood. With a focus on the microbiome as it pertains to mental health, we define environmental “grey space” and emphasize a new frontier involving bio-eco-psychological medicine. Within this concept the ecological terrain can link dysbiotic lifestyles and biodiversity on the grand scale to the local human-associated microbial ecosystems that might otherwise seem far removed from one another.

Nonnative forest insects and pathogens in the United States: Impacts and policy options

We review and synthesize information on invasions of nonnative forest insects and diseases in the United States, including their ecological and economic impacts, pathways of arrival, distribution within the United States, and policy options for reducing future invasions. Nonnative insects have accumulated in United States forests at a rate of ~2.5 per yr over the last 150 yr. Currently the two major pathways of introduction are importation of live plants and wood packing material such as pallets and crates. Introduced insects and diseases occur in forests and cities throughout the United States, and the problem is particularly severe in the Northeast and Upper Midwest. Nonnative forest pests are the only disturbance agent that has effectively eliminated entire tree species or genera from United States forests within decades. The resulting shift in forest structure and species composition alters ecosystem functions such as productivity, nutrient cycling, and wildlife habitat. In urban and suburban areas, loss of trees from streets, yards, and parks affects aesthetics, property values, shading, stormwater runoff, and human health. The economic damage from nonnative pests is not yet fully known, but is likely in the billions of dollars per year, with the majority of this economic burden borne by municipalities and residential property owners. Current policies for preventing introductions are having positive effects but are insufficient to reduce the influx of pests in the face of burgeoning global trade. Options are available to strengthen the defenses against pest arrival and establishment, including measures taken in the exporting country prior to shipment, measures to ensure clean shipments of plants and wood products, inspections at ports of entry, and post-entry measures such as quarantines, surveillance, and eradication programs. Improved data collection procedures for inspections, greater data accessibility, and better reporting would support better evaluation of policy effectiveness. Lack of additional action places the nation, local municipalities, and property owners at high risk of further damaging and costly invasions. Adopting stronger policies to reduce establishments of new forest insects and diseases would shift the major costs of control to the source and alleviate the economic burden now borne by homeowners and municipalities.

Neighborhood Greenness and Chronic Health Conditions in Medicare Beneficiaries

INTRODUCTION

Prior studies suggest that exposure to the natural environment may impact health. The present study examines the association between objective measures of block-level greenness (vegetative presence) and chronic medical conditions, including cardiometabolic conditions, in a large population-based sample of Medicare beneficiaries in Miami-Dade County, Florida.

METHODS

The sample included 249,405 Medicare beneficiaries aged ≥65 years whose location (ZIP+4) within Miami-Dade County, Florida, did not change, from 2010 to 2011. Data were obtained in 2013 and multilevel analyses conducted in 2014 to examine relationships between greenness, measured by mean Normalized Difference Vegetation Index from satellite imagery at the Census block level, and chronic health conditions in 2011, adjusting for neighborhood median household income, individual age, gender, race, and ethnicity.

RESULTS

Higher greenness was significantly associated with better health, adjusting for covariates: An increase in mean block-level Normalized Difference Vegetation Index from 1 SD less to 1 SD more than the mean was associated with 49 fewer chronic conditions per 1,000 individuals, which is approximately similar to a reduction in age of the overall study population by 3 years. This same level of increase in mean Normalized Difference Vegetation Index was associated with a reduced risk of diabetes by 14%, hypertension by 13%, and hyperlipidemia by 10%. Planned post-hoc analyses revealed stronger and more consistently positive relationships between greenness and health in lower- than higher-income neighborhoods.

CONCLUSIONS

Greenness or vegetative presence may be effective in promoting health in older populations, particularly in poor neighborhoods, possibly due to increased time outdoors, physical activity, or stress mitigation.

Healthy people with nature in mind

Background

The global disease burden resulting from climate change is likely to be substantial and will put further strain on public health systems that are already struggling to cope with demand. An up- stream solution, that of preventing climate change and associated adverse health effects, is a promising approach, which would create win-win-situations where both the environment and human health benefit. One such solution would be to apply methods of behaviour change to prompt pro-environmentalism, which in turn benefits health and wellbeing.

Discussion

Based on evidence from the behavioural sciences, we suggest that, like many social behaviours, pro- environmental behaviour can be automatically induced by internal or external stimuli. A potential trigger for such automatic pro-environmental behaviour would be natural environments themselves.

Previous research has demonstrated that natural environments evoke specific psychological and physiological reactions, as demonstrated by self-reports, epidemiological studies, brain imaging techniques, and various biomarkers. This suggests that exposure to natural environments could have automatic behavioural effects, potentially in a pro-environmental direction, mediated by physiological reactions.

Providing access and fostering exposure to natural environments could then serve as a public health tool, together with other measures, by mitigating climate change and achieving sustainable health in sustainable ecosystems. However, before such actions are implemented basic research is required to elucidate the mechanisms involved, and applied investigations are needed to explore real world impacts and effect magnitudes. As environmental research is still not sufficiently integrated within medical or public health studies there is an urgent need to promote interdisciplinary methods and investigations in this critical field.

Summary

Health risks posed by anthropogenic climate change are large, unevenly distributed, and unpredictable. To ameliorate negative impacts, pro-environmental behaviours should be fostered. Potentially this could be achieved automatically through exposure to favourable natural environments, with an opportunity for cost-efficient nature-based solutions that provide benefits for both the environment and public health.