Spatial dimensions of the influence of urban green-blue spaces on human health: A systematic review

Residential greenness and chronic obstructive pulmonary disease in a large cohort in southern China: Potential causal links, risk trajectories, and mediation pathways

INTRODUCTION

Residential greenness may influence COPD mortality, but the causal links, risk trajectories, and mediation pathways between them remain poorly understood.

OBJECTIVES

We aim to comprehensively identify the potential causal links, characterize the dynamic progression of hospitalization or posthospital risk, and quantify mediation effects between greenness and COPD.

METHODS

This study was conducted using a community-based cohort enrolling individuals aged ≥ 18 years in southern China from January 1, 2009 to December 31, 2015. Greenness was characterized by normalized difference vegetation index (NDVI) around participants' residential addresses. We applied doubly robust Cox proportional hazards model, multi-state model, and multiple mediation method, to investigate the potential causal links, risk trajectories among baseline, COPD hospitalization, first readmission due to COPD or COPD-related complications, and all-cause death, as well as the multiple mediation pathways (particulate matter [PM], temperature, body mass index [BMI] and physical activity) connecting greenness exposure to COPD mortality.

RESULTS

Our final analysis included 581,785 participants (52.52% female; average age: 48.36 [Standard Deviation (SD): 17.56]). Each interquartile range (IQR: 0.06) increase in NDVI was associated with a reduced COPD mortality risk, yielding a hazard ratio (HR) of 0.88 (95 % CI: 0.81, 0.96). Furthermore, we observed per IQR (0.04) increase in NDVI was inversely associated with the risk of multiple transitions (baseline - COPD hospitalization, baseline - death, and readmission - death risks), especially a declined risk of all-cause death after readmission (HR = 0.66 [95 %CI: 0.44, 0.99]). Within the observed association between greenness and COPD mortality, three mediators were identified, namely PM, temperature, and BMI (HR for the total indirect effect: 0.773 [95 % CI: 0.703, 0.851]), with PM showing the highest mediating effect.

CONCLUSIONS

Our findings revealed greenness may be a beneficial factor for COPD morbidity, prognosis, and mortality. This protective effect is primarily attributed to the reduction in PM concentration.

Association of greenness exposure with serum vitamin D status and effects of ambient particulate matter among pregnant women in early pregnancy

Adequate vitamin D is essential for the health of both the mother and fetus, and it can be influenced by environmental factors. However, research on the associations between greenness exposure and vitamin D concentrations during pregnancy is limited. This retrospective birth cohort study, conducted from 2014 to 2018, assessed the greenness of residences using the satellite-derived normalised difference vegetation index (NDVI). Serum 25-hydroxyvitamin D [25(OH)D] concentrations were categorised as non-deficient (≥50 nmol/L) or deficient (<50 nmol/L). Multiple log-binomial regression models were used to estimate the association of NDVI with serum 25(OH)D concentrations and vitamin D deficiency (VDD). Subgroup and mediation analyses were conducted to estimate the association of ambient particulate matter (PM) on the association between NDVI and VDD. A total of 64,663 pregnant women with a mean maternal age of 30.6 (standard deviation: 3.86) years were included. 250-m NDVI was negatively associated with the risk of VDD (per 0.1-unit increase, relative risk [RR]: 0.98, 95 % CI: 0.97-0.99). With the highest quartile of NDVI exposure as the reference group, the upper-middle quartile (RR: 1.02, 95 % CI: 1.00-1.03), and lowest quartile (RR: 1.03, 95 % CI: 1.01-1.06) had an increased risk of VDD. At higher PM2.5 exposure concentrations, 250-m NDVI exposure was negatively associated with the risk of VDD (RR: 0.98, 95 %CI: 0.97-0.99, per 0.1-unit increase), but not at lower PM2.5 exposure concentrations. Among pregnant women with higher PM2.5, the mediation of PM2.5 exposure on the association between 250-m NDVI and VDD was 44.70 % (P = 0.0116). Among pregnant women with higher PM10 exposure, the mediation of PM10 exposure on the association between 250-m NDVI and VDD was 17.98 % (P = 0.002). These findings suggest that higher residential greenery significantly reduces the risk of VDD in pregnant women, particularly in those exposed to increased PM concentrations.

Residential environment and risk of chronic diseases: A prospective study

The impact of green-blue spaces on human health remains inconclusive, and the current understanding of disease spectrum associated with these spaces is still incomplete. We aimed to comprehensively investigate the relationship between residential environment and chronic diseases, while also examining the potential mediating role of air pollutants in these relationships. Using data from the UK Biobank, we created a residential environment score (RES) based on four types of green-blue spaces: natural environment, green space, domestic garden, and water area, with scores assigned according to the percentage of each space within a 300 m buffer. We also calculated an air pollution score derived from concentrations of NO2, NOx, PM2.5, PM2.5-10, and PM10. Employing logistic regression and Cox regression models, we analyzed the associations between RES and multisystem health outcomes among 502,490 participants at baseline. Our assessment identified 41 chronic diseases across 12 categories significantly related to RES increases (false-discovery-rate adjusted P-values < 0.01). Cox regression indicated that higher RES was associated with reduced risks for 18 diseases, excluding melanoma and bladder cancer. For the 21 unreported outcomes such as iron deficiency anemia and purpura, we observed hazard ratios (95 %CI) indicating lower risks for various conditions in the highest quartile of RES compared to the lowest. Furthermore, air pollution significantly mediated the relationship between RES and over 90 % of these chronic diseases. Residential environment with abundant green-blue spaces is linked to lower risks of most chronic diseases, which is partially mediated by diminished air pollutants and largely underestimated.

Restoring nature, enhancing active mobility: The role of street greenery in the EU's 2024 restoration law

This article argues for the importance of integrating a mobility perspective into urban greenspace planning and practice related to the 2024 EU Nature Restoration Law. Street greenery can play an important multifunctional role in promoting ecosystem services and functions, sustainable mobility, and human health and well-being. However, planners need more evidence on how street vegetation affects health and well-being during everyday active mobility, as well as what type, where and for whom to enhance vegetation. We discuss current advancements and gaps in literature related to these topics, and identify key research priorities to support restoration policy and practice. These include: moving beyond dominant scientific thinking of being in place to moving through space in understanding greenery exposure and experience; use of multiple exposure metrics with attention to temporal dynamics; integration of objective and subjective assessments; and investigating further the role of street greenery in reducing environmental injustices.

Impact of Different Greenspace Metrics on Cardiovascular Disease Incidence in Urban Settings: A Comparative Analysis

Cardiovascular diseases (CVDs) are the leading cause of global mortality, and urban greenspace can reduce CVDs risk. However, the evidence relating various greenspace metrics to CVDs risk is inconclusive. To enhance the understanding of the correlation between greenspace and CVDs, we compared three greenspace indicators-street view-based greenspace (SVG), normalized difference vegetation index (NDVI), and green cover rate (GCR). We used a large sample of 36,504 CVDs hospitalization records with precise residential addresses from 2017 to 2022 in Jingzhou, China. Employing the geographically weighted regression (GWR) model, we investigated the association between greenspace and CVDs incidence at the population level. We found significant negative associations between NDVI/SVG and CVDs incidence (SVG: β = - 1.64; 95% CI, [- 2.12, - 1.15]; NDVI: β = - 8.57; 95% CI, [- 9.81, - 7.33]), with NDVI exhibiting a more substantial protective effect. However, no significant relationship was found in GCR (p = 0.161). The impacts varied by age, but not by gender, with younger individuals benefiting more than the elderly, and SVG showed no significant relationship with CVDs incidence in individuals over 65 years. Our findings suggested the importance of the presence of greenspace in CVDs prevention. Consequently, in urban greenspace planning, priority should be given to the vegetation quantity in residential areas over the size of greenspace facilities located distant from residences.

Nature's impact on human health and wellbeing: the scale matters

Contact with nature can have a significant influence on human physical and mental health and wellbeing. As such, various concepts and theories as well as therapeutic approaches have been developed. The term "nature," however, covers a broad range of size and scales, ranging from individuals or small groups of animals or plants, certain ecosystems toward landscapes. The purpose of this paper is to differentiate concepts, theories, and therapy forms according to the scales of nature. We base our conceptional approach on the biological/ecological scales of species/individuals, ecosystems/land-use types, and landscapes. Based on a review, we differentiate the current state of the utilization of greenspace exposure measurements and measures assessing mental health according to these scales. We argue that a clear differentiation of biological and ecological scales provides a better understanding of the impact of nature with its components, characteristics, and dynamics on human health and wellbeing. Our paper also supports further inter- and transdisciplinary research as well as methodological approaches with regard to environment and health, such as environmental public health.

Associations of green and blue spaces with visual acuity in youths from Shandong Province, China: A large population-based study

While growing evidence highlights the benefits of green and blue spaces for physical and mental health, their combined effects on youth visual acuity remain unclear. This study aimed to evaluate the associations of green and blue spaces with visual acuity in youths. We analyzed data from the 2023 Common Disease and Health Risk Factors Surveillance and Intervention Program among students in Shandong Province, China. Generalized linear mixed-effects models were employed to investigate the independent associations of green and blue spaces with visual acuity in youths. To explore potential interactions, an interaction term for green and blue spaces was incorporated. Quantile g-computation (Qgcomp) models were applied to evaluate their combined effects. Compared to the lowest quartile, higher quartiles (Q2, Q3, and Q4) of the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), normalized difference water index (NDWI), and modified normalized difference water index (MNDWI) were significantly associated with improved visual acuity in both eyes. Additionally, each 0.1 unit increase in NDVI500, EVI500, NDWI500, and MNDWI500 was associated with 0.008 (95 % confidence interval [CI]: 0.007, 0.010), 0.003 (0.002, 0.004), 0.054 (0.028, 0.080), and 0.010 (0.002, 0.018) improvements in right-eye visual acuity, with similar findings for the left eye. A significant interaction was observed between NDVI and NDWI (all P for interaction < 0.001), and combined exposure to green and blue spaces was positively associated with visual acuity (all P < 0.001). Furthermore, demographic and lifestyle factors modified the associations of blue and green spaces with visual acuity levels in youths. Greater exposure to green and blue spaces may benefit visual health in youths, with potential interactive and combined effects. Implementing policies to enhance the availability of green and blue spaces around schools may offer opportunities to alleviate visual impairment in youths.

Maternal green space exposure and congenital heart defects: A population-based study

BACKGROUND

Beneficial effects of maternal green space exposure on preterm birth and low birth weight have been documented, but few studies have investigated its protective effect on fetal congenital heart defects (CHDs). Our study aimed to investigate the association between maternal green space exposure and CHDs, and quantify the potential benefits of reducing the risk of fetal CHDs by achieving the target of green space coverage.

METHODS

The study included 4160 births with CHDs and 567,483 births without birth defects born from 2014 to 2019 in 14 cities in Liaoning Province, China. Maternal green space exposure, including periconception period (3 months before conception to 3 months into pregnancy), preconception period (3 months before conception), and the first trimester (3 months into pregnancy), was assessed using satellite-based normalized difference vegetation index (NDVI). Logistic regression models were used to estimate the associations between maternal green space exposure and the risk of fetal CHDs.

RESULTS

A 0.1-unit increase in maternal green space exposure during the periconception was significantly associated with 5% declines in the risk of CHDs (OR: 0.95, 95% CI: 0.92, 0.98). Exposure-response association suggested that continuous improvements in maternal green space exposure during the periconception had a greater protective impact on the risk of total CHDs, while attenuated benefits were identified in the area where NDVI is around 0.23. Assuming causality, 5.06% (95% CI: 1.72%, 8.28%) of the annual rate of CHDs could be avoided by increasing NDVI exposure to 0.23 during periconception period in the areas where NDVI is below 0.23. In addition, rural residents, and mothers who have parity twice or more, were more prone to the protective effect of green space exposure.

CONCLUSIONS

Our study provides evidence that maternal green space exposure is a protective factor against the risk of fetal CHDs. The findings suggest that prioritizing green space in public policy can be an effective health-promoting measure.

Factors influencing the effectiveness of nature-based interventions (NBIs) aimed at improving mental health and wellbeing: An umbrella review

Several systematic reviews support nature-based interventions (NBIs) as a mechanism of enhancing mental health and wellbeing. However, the available evidence for the effectiveness of these interventions is fragmentary and mixed. The heterogeneity of existing evidence and significant fragmentation of knowledge within the field make it difficult to draw firm conclusions regarding the effectiveness of NBIs. This can only limit the development of interventions to support personal and planetary wellbeing, potentially resulting in ineffective and ill-targeted investment decisions. These concerns have hindered the translation of research evidence into practice and guidelines are urgently required to assist researchers, practitioners and policymakers in developing interventions to promote environmental stewardship and meet the health needs of diverse communities. A higher-order or meta-level synthesis is required to make sense of this evidence. This umbrella review synthesises evidence on the barriers and enablers to nature-based interventions through a summative review of existing published systematic reviews and meta-analyses. A systematic search in PsycINFO, PubMed, Greenfile, Web of Science, Embase, Scopus, Academic Search Complete (EBSCO), Environment Complete (EBSCO), Cochrane Library, CINAHL, Health Policy Reference Centre and Google Scholar was performed. This is a mixed method review, and systematic reviews with both quantitative and qualitative data synthesis were included. 64 systematic reviews were included in the synthesis. The descriptive data, extracted from each study, forms an overview of the characteristics of available evidence on nature-based interventions. A narrative synthesis is used to present the potential factors influencing the outcomes of NBIs. The risk of bias of the systematic reviews was assessed using a 16-item Assessment of Multiple Systematic Reviews 2 (AMSTAR2) checklist. Directions for future research, potential quality needs and recommendations for future research, policymaking, and practice are discusssed.

A systematic review of the associations between biodiversity and children's mental health and wellbeing

There is a growing interest in how exposure to biodiversity influences mental health and wellbeing; however, few studies have focused on children. The aim of this review was to identify studies that used components of biodiversity and children's health outcomes to assess if there were any themes that could be used to inform urban design and understand the mechanisms behind associations. We used a PROSPERO registered protocol to identify eligible studies following pre-defined inclusion criteria. After searching five databases, 25 studies were included in the review. From these articles we extracted data on the biodiversity exposure and mental health and wellbeing outcomes. Five categories of biodiversity exposure were identified, including species diversity (n = 1; 4%), functional diversity (n = 6; 26%), ecological community (n = 9; 36%), green space metrics (n = 4; 16%), and high-level classifications (n = 6; 24%). Children's health and wellbeing were tabulated into seven categories: play (n = 10; 40%), wellbeing (n = 6; 24%), mental health and cognitive functioning (n = 5; 20%), attention deficit hyperactivity disorder (ADHD)-related behaviours (n = 4; 16%), preferences for nature (n = 3; 12%), academic achievement (n = 2; 8%), and restoration (n = 2; 8%). The high heterogeneity of biodiversity and health measures reduced our ability to identify relationships across studies and formally test for an exposure-dose response. Future research that uses standardised and transferable biodiversity measurements at multiple scales, has stronger reporting rigour, greater consideration of potential modifiers, and increased representation of studies from the Majority World are essential for building a stronger evidence base to deliver child-centred biodiverse landscapes.

Neighborhood socioeconomic disparities in cancer incidence following a hypothetical intervention to increase residential greenspace cover in the UK Biobank cohort

BACKGROUND

Higher greenspace exposure has been associated with lower risk of certain cancers. However, few studies have evaluated potential benefits of increasing population-level exposure to greenspace on cancer disparities. We estimated the impact of a hypothetical intervention to increase residential greenspace cover on neighborhood socioeconomic disparities in total, breast, colorectal, lung, and prostate cancer incidence.

METHODS

Our study included 411,787 cancer-free UK Biobank participants. Percentage of greenspace around baseline residential addresses (300m, 1000m distance buffers) was derived by combining domestic gardens and greenspace cover from the Generalized Land Use Database. We categorized neighborhood socioeconomic deprivation using the Index of Multiple Deprivation (2010). We estimated hazard ratios (HR) and 95% confidence intervals (CI) of each cancer associated with greenspace, adjusting for sociodemographic and lifestyle factors. We additionally adjusted for air pollution in supplementary analyses as we a-priori hypothesized that it was on the causal pathway between greenspace and cancer. Further, we used parametric g-computation to calculate the standardized 10-year risk of each cancer, comparing the least to most socioeconomically disadvantaged participants, both without any hypothetical greenspace intervention and under a hypothetical intervention to increase residential greenspace cover to a favorable threshold (75th percentile amongst the least socioeconomically deprived participants).

RESULTS

We documented 40,519 incident cases of cancer over 4,210,008 person-years follow-up. An interquartile range increase in greenspace cover within 300m was associated with lower incidence of total (HR 0.98; 95% CI 0.97, 1.00) and lung (HR 0.96; 95% CI 0.92, 0.99) cancer, and was suggestively associated with lower prostate and breast cancer incidence, but not colorectal cancer. Additional adjustment for fine particulate matter air pollution (PM2.5) weakened lung cancer associations but strengthened breast and prostate cancer associations (e.g., greenspace 1000m breast cancer HR 0.94; 95% CI 0.89 0.99; 1000m prostate cancer HR 0.91; 95% CI 0.86, 0.95). The hypothetical intervention to increase greenspace (300m) resulted in 1.3 fewer total cancer cases per 1000 (95% CI 1.0, 1.6) in the most compared to least deprived group, a 23% reduction in the socioeconomic disparity gap.

DISCUSSION

Higher residential greenspace cover was associated with lower total and lung cancer incidence, and suggestively associated with lower breast and prostate cancer incidence. Policies to increase residential greenspace cover may reduce the risk of certain cancers, particularly among socioeconomically disadvantaged groups.

Challenges in nature-based health and therapy research and critical considerations for application in musculoskeletal health

Nature-based health and therapy (NBHT) is a term incorporating a broad suite of practices that focus on engagement with the natural world and nature-rich spaces for potential physical and mental health benefits. As healthcare professions such as physiotherapy and osteopathy move away from biomedical/reductionist models of care for complex conditions towards approaches which take into account social and environmental determinants of health, NBHT may become part of clinical interventions and public health messaging. However, there are multiple challenges in aspects of NBHT research and application, from methodological issues in the primary research base, to questions of environmental injustice and access inequalities in many areas. In addition, engaging with natural environments which are vulnerable to the entwinned threats of climate change and biodiversity collapse requires consideration of the effects of ecological disturbance and the underlying anthropocentric/utilitarian view of the natural world. In this perspective, we outline a critique of NBHT literature and offer positive suggestions for how better-quality research can be conducted and implemented by focusing on local environmental, social, and political factors. We conclude by outlining a set of critical considerations that healthcare professionals might use to develop and implement NBHT programmes in their specific regional contexts.

Exploring the pathways linking prenatal and early childhood greenness exposure to attention-deficit/hyperactivity disorder symptoms during childhood: An approach based on robust causal inference

BACKGROUND

Epidemiological studies suggest that exposure to greenness during childhood may protect children from developing attention-deficit hyperactivity disorder (ADHD).

OBJECTIVE

We analyzed the effect of both prenatal (pregnancy) and early childhood (4-5-year follow-up) residential greenness exposure and green space availability on ADHD symptoms during childhood (up to the age of 12 years) and further explored the potential mediating role of PM2.5 and physical activity in the association.

METHODS

The study population included participants from the INfancia y Medio Ambiente (INMA) prospective birth cohort (Gipuzkoa, Sabadell, and Valencia). Average Normalized Difference Vegetation Index (NDVI) in buffers of 100-, 300- and 500-m around the residential addresses was used as an indicator of greenness, while green space availability was determined based on the presence of a major green space within 150-m from the residence. Childhood ADHD symptoms were assessed at the 6-8- and 10-12-year follow-ups using Conners Parents Rating Scale-Revised: Short Form.

RESULTS

Although no association was found for the prenatal exposure period, increased early childhood NDVI inversely associated with the OR of clinically significant ADHD symptoms during the 6-8-year follow-up at the 100-m (OR 0.03, 95% CI: 0.003 to 0.44), 300-m (OR 0.04, 95% CI: 0.003 to 0.42) and 500-m (OR 0.08, 95% CI: 0.01 to 0.76) buffers, but exclusively in the context of direct effects. Additionally, the 10-12-year follow-up analysis found moderate to weak evidence of potential total and direct effects of NDVI at both 100- and 300-m buffers on inattention scores, as well as for NDVI at the 300-m buffer on ADHD index scores. The analysis did not reveal evidence of mediation through PM2.5 or physical activity.

CONCLUSIONS

The evidence suggests that early childhood greenness exposure may reduce the risk of developing ADHD symptoms later in childhood, and that this association is not mediated through PM2.5 and physical activity.

The influence of freshwater blue spaces on human health and well-being:A systematic review based on assessment method

An increasing number of studies have explored the positive effects of blue spaces on human health, much of which involves the impacts of various blue space exposures on human health indicators, recognizing that the diversity in assessment methods may influence the final results. However, there are currently few systematic reviews that comprehensively synthesize this evidence. Additionally, current reviews in this field predominantly focus on coastal environments, while Freshwater Blue Spaces(FBS)receive less attention. Given that more than 50% of the global population lives within 3 km of freshwater bodies, it is crucial to understand the health impacts of these unique environments. Therefore, this study aims to systematically review the existing literature on the effects of FBS on human health and identify knowledge gaps. We systematically reviewed 34 articles following the PRISMA protocol. The results showed six main FBS exposure assessment methods and ten related health indicators. Additionally, we identified 74 health indicators and their relation to FBS exposure assessments. Our findings revealed: (i) FBS exposure assessment methods are becoming more diverse and refined, but challenges and limitations persist in their application; (ii) the studies employed a range of health indicators to explore different dimensions of human health, yet significant differences exist in their focus and methodologies; (iii) The results on the association between FBS and health exhibit heterogeneity, which not only depends on the health focus and indicators of each study but is also related to the exposure assessment methods used, the characteristics of FBS, sample differences, and the rigor of bias evaluation and control of confounding factors. Based on our findings, we propose a series of recommendations to further investigate the intrinsic connections between FBS and human health, providing opportunities to enhance human health and well-being.

Green space quantity and exposure in relation to the risk of immune-mediated diseases: a scoping review

The growing global incidence of immune-mediated and inflammatory diseases (IMIDs) is worrisome, with evidence suggesting that environmental factors, notably urbanization and the reduction of green spaces, may act as potential instigators. However, conflicting findings in studies necessitate a closer examination of recent research (January 2020 - February 2024) to elucidate the factors contributing to these inconsistencies. This review explores study protocols to avoid erroneously endorsing the null hypothesis of no association between green space coverage and IMID risks. A literature search adhering to PRISMA-ScR guidelines yielded 46 relevant papers from Google Scolar and Pub Meb. The studies varied in design, with 17 being longitudinal, 24 cross-sectional, and five focusing on longitudinal parent-offspring connections. Geographic scope differed, with 21 multi-location and 25 single-location studies. Participant numbers ranged from 144 to 982,131 across diverse demographics. Additionally, some studies examined disease frequencies in large groups (several million people) residing in specific regions. Green space metrics encompassed NDVI, land cover data, plant biodiversity, and novel indexes, measured within 7.5-5000 m diameter buffers around residences or schools. The review advises against making definitive statements regarding the relationship between urban green spaces and the prevalence of IMIDs. It suggests that inconsistencies in study results may stem from variations in study designs and methodologies, as well as the complex, interacting mechanisms through which green spaces affect immune health. Future research recommendations include larger cohorts, early-life exposure data, and testing specific hypotheses related to vegetation types and participants' genetic predispositions.

Aggregated hedonic dataset with a green index: Busan, South Korea

We provide an aggregated dataset for investigating the association between hedonic variables and property prices in the Busan Metropolitan City of South Korea. This hedonic dataset includes various factors that influence property prices such as property characteristics, environmental amenities, local built environments, local demographic characteristics, and seasonal controls. In this dataset, we introduce the green index, which quantifies the degree of urban street greenness exposed to residents and pedestrians using images from Google Street View. In addition, the spatial interpolation method is employed to resolve the nonuniform distribution issue of the source images. To encourage the reusability of the dataset, we provide data and code files in a convenient manner. Therefore, the aggregated hedonic dataset can be readily benchmarked in property appraisal and urban studies and utilized in geographic information system fields.

Urban green vitalization and its impact on green exposure equity: A case study of Shanghai city, China

Urban green space (UGS) provides multiple ecosystem services to enhance the residents' well-being in the cities. As a characterization of differences in the degree of interaction between residents and UGS, Green exposure equity, has been recognized as an environmental justice issue. In this study, we propose the concept of urban green space' vitalization (UGV) as a primary criterion for assessing whether the UGS' functions or services are realized. Taking Shanghai, China as a case study, we developed an assessment system for UGV, and quantified UGV's availability to examine the impact on green exposure equity. Our research shows that 1000 m is the optimal service radius to determine whether UGS vitality is realized. All UGS in the central regions of Shanghai have realized their vitality, while areas devoid of vitality are mainly located in the non-central. Compared to UGS, the availability of UGV in Shanghai was cumulatively reduced by 321.07 km2, 10,812.61 km2, and 197,496.54 km2 for walking, public transport, and driving modes, respectively. In the non-central regions, the minimum green availability per capita for walking and public transport modes was reduced to 0 ha. The influence of UGV on green exposure equity varies depending on research scales and travel modes, as it is affected by heterogeneity in the distribution of UGS and population. Our research confirmed that UGV significantly reduces green availability and influences green exposure equity. Green exposure equity could be significantly improved by UGV under public transport mode and the district scale. Therefore, UGV is an essential factor in quantifying the equity of green exposure. Our research can serve as a basis for more realistic measurements of green exposure equity, providing insights for improving environmental justice in sustainable cities.

Early-life exposure to residential greenness and risk of asthma in a U.S. bronchiolitis cohort

INTRODUCTION

Severe bronchiolitis (i.e., bronchiolitis requiring hospitalization) is linked to childhood asthma development. Despite a growing understanding of risk factors for developing post-bronchiolitis asthma, protective factors remain unclear. In this study, we aimed to investigate whether exposure to residential greenness between birth and bronchiolitis hospitalization is associated with asthma and atopic asthma development by age 6 years.

METHODS

We analyzed a US severe bronchiolitis cohort from hospitalization to age 6 years, investigating how the normalized difference vegetation index (NDVI) and chlorophyll index green (CI green), measured in small (100 m) and large (500 m) radiuses around homes, relate to asthma and atopic asthma by age 6 years. We also explored whether maternal antibiotic use, daycare attendance, and respiratory virus type during hospitalization act as effect modifiers.

RESULTS

The study cohort included 861 infants, with 239 (28%) developing asthma by age 6 years-152 atopic, 17 nonatopic, and 70 unclassified. Early life residential exposure to high NDVI and CI green levels was associated with lower odds of asthma (ORAdj for NDVI within a 100 m radius, 0.18; 95% CI, 0.05-0.78; and ORAdj for CI green levels within a 100 m radius, 0.53; 95% CI, 0.31-0.90). Associations also were significant for the development of atopic asthma (ORAdj 0.16; 95% CI, 0.03-0.96; and ORAdj 0.46; 95% CI, 0.25-0.92; respectively). Results were similar for the 500 m radius exposures. No effect modification was noted.

CONCLUSION

In a U.S. bronchiolitis cohort, exposure to residential greenness between birth and bronchiolitis hospitalization is linked to lower asthma and atopic asthma risk by age 6 years.

Exposure to residential greenness, perceived stress, and depressive symptoms in a North American preconception cohort

BACKGROUND

Studies suggest that greater exposure to natural vegetation (i.e., greenness) is associated with better mental health. However, there is limited research on greenness and mental health in the preconception period, a critical window of exposure in the life course. We investigated the associations of residential greenness with perceived stress and depressive symptoms using cross-sectional data from a cohort of pregnancy planners.

METHODS

From 2013 to 2019, we enrolled female-identified participants aged 21-45 years who were trying to conceive without the use of fertility treatment into a North American preconception cohort study (Pregnancy Study Online [PRESTO]). On the baseline questionnaire, participants completed the 10-item Perceived Stress Scale (PSS) and the Major Depression Inventory (MDI). Using geocoded addresses, we estimated residential greenness exposure via satellite imagery (Normalized Difference Vegetation Index [NDVI]) in a 100m buffer. We estimated mean differences and 95% confidence intervals for the association of greenness with perceived stress and depression scores using linear regression models, adjusting for individual and neighborhood sociodemographic characteristics. We also evaluated the extent to which associations were modified by urbanicity and neighborhood socioeconomic status (SES).

RESULTS

Among 9718 participants, mean age was 29.9 years, 81.5% identified as non-Hispanic White, 25% had household incomes <$50,000, and mean neighborhood income was $61,932. In adjusted models, higher greenness was associated with lower stress and depression scores (mean difference per interquartile range in greenness: -0.20, 95% CI: -0.39, -0.01; and -0.19, 95% CI: -0.48, 0.10, respectively). The association was stronger among residents of lower SES neighborhoods in urban areas (PSS: -0.57, 95% CI: -1.00, -0.15; MDI: -0.72, 95% CI: -1.40, -0.04).

CONCLUSIONS

Higher greenness exposure was associated with lower stress and depressive symptoms among pregnancy planners, particularly in lower-SES neighborhoods.

Local environment perceived in daily life and urban green and blue space visits: Uncovering key factors for different age groups to access ecosystem services

Inequality in access to green and blue spaces is a major issue in the field of environmental justice. Various factors significantly influence visitations to these spaces, including residential, commuting, and shopping areas. However, studies have mainly focused on residential environments. Analyzing the coupling of environmental and socioeconomic factors, including age, income, and childhood experience, and examining the direct and indirect effects of these factors for different age groups are needed to better understand the detailed context of inequalities in access to ecosystem services. We conducted a questionnaire survey and analysis to address these needs in an urban setting. The results demonstrate that several land use categories (i.e., agricultural lands in residential areas, grasslands near shopping areas, and deciduous forests near commuting destinations) positively correlated with visitation frequency, suggesting the lack thereof may be the cause of access inequalities. In particular, the perimeter per unit area of some land cover types, which shows the complexity of the form of each land cover category, was found to be a significant factor. We identified inequality in nature experience to be the key factor correlated with inequality in nature visits among the young age group. For the middle-aged and old age groups, nature-relatedness was positively correlated with visitation frequency. Proper design of the local environment, such as through land use planning, can be an effective measure for all age groups. For instance, long-bordered green areas in the Monsoon Asian region are an attractive traditional landscape, with high accessibility and a comfortable thermal environment. The key factors for each age group should be considered in spatial design and inclusive information-sharing to reduce inequality in access to ecosystem services.

ECO-MIND: enhancing pro-environmental behaviours and mental health through nature contact for urban youth - a research protocol for a multi-country study using geographic ecological momentary assessment and mental models

INTRODUCTION

Urban youth are experiencing increasing mental health problems due to diverse personal, social and environmental concerns. Youths' detachment from natural environments, including green and blue spaces, may intensify such issues further. Contact with nature can benefit mental health and promote pro-environmental behaviour (PEB). Yet, only a few studies assess these relationships among the youth usually ignoring effects of living in diverse urban contexts, and everyday nature experiences. ECO-MIND will investigate whether urban youth's dynamic greenspace exposure and their mental models about nature connectedness explain the associations between greenspace exposure, mental health and PEB in multiple urban contexts.

METHODS AND ANALYSIS

We will collect data from university students from the Global South (ie, Dhaka, Kampala) and Global North cities (ie, Utrecht). Participants aged 18-24 will be recruited through stratified random sampling. We will use geographic ecological momentary assessment to assess respondents' everyday experiences and exposure to greenspaces. Our definition of greenspace exposure will be based on the availability, accessibility and visibility of greenspaces extracted from satellite and street view images. We will administer a baseline questionnaire to participants about mental health, nature connectedness and PEB characteristics. Further, we will ask participants to build mental models to show their perception of nature connectedness. Finally, we will fit partial least square structural equation models and multi-level models to our longitudinal geographic momentary assessment data.

ETHICS AND DISSEMINATION

The study was approved by the Ethical Review Board of the Utrecht University (Geo S-23221). Informed consent must be given freely, without coercion and based on a clear understanding of the participation in the study. Findings will be disseminated in peer-reviewed journals and at conferences. Furthermore, we will implement public engagement activities (eg, panel discussion) to share results among local stakeholders and policymakers and cocreate policy briefs.

How Green Space Justice in urban built-up areas affects public mental health: a moderated chain mediation model

Background

Green and blue spaces, as crucial components of urban ecosystems, significantly impact the physical and mental health of residents. However, the mechanisms through which Green/Blue Space Justice influence residents' health remain unclear.

Methods

This study aims to explore the impact of green spaces on public psychological responses, physical activity, and mental health from a justice perspective, and to examine the moderating role of blue spaces in this relationship. The research was conducted in selected communities within the Chang-Zhu-Tan urban agglomeration in Hunan Province, China. A total of 801 valid questionnaires were collected through field visits and online surveys. The study uses an improved Gaussian-based two-step floating catchment area (2SFCA) method to assess green space accessibility. Data were analyzed using structural equation modeling (SEM) and moderation effect analysis to reveal the relationships between variables.

Results

The findings indicate that Green Space Justice has a significant positive impact on psychological responses, physical activity, and mental health; psychological responses and physical activity play crucial mediating roles between Green Space Justice and mental health; and Green Space Justice significantly affects mental health through a chain mediation path involving psychological responses and physical activity. Moreover, Blue Space Justice significantly moderates the impact of Green Space Justice on psychological responses and physical activity, but does not have a significant direct impact on mental health.

Conclusion

This study enriches the theory of Green Space Justice by revealing the mechanisms through which it influences mental health via psychological responses and physical activity. It provides a scientific basis for the development of healthy cities. Additionally, it recommends that urban planning should prioritize the equitable distribution and high accessibility of both green and blue spaces to comprehensively enhance residents' physical and mental well-being. Policymakers should consider prioritizing the accessibility of high-quality green spaces for vulnerable communities during urban renewal and expansion processes to reduce social health inequalities and promote broader public health outcomes.

Spatiotemporal variability of the association between greenspace exposure and depression in older adults in South Korea

BACKGROUND

A number of studies based on young to middle aged adult and child samples have found that exposure to greenspace and bluespace can have a positive impact on mental health and well-being. However, there is limited research among older adults and the extant studies have provided mixed results. The present study was designed to examine how the association between these forms of exposure and depressive symptoms among older adults varies as a function of different spatially and temporally resolved exposure metrics.

METHODS

The sample consisted of 617 individuals (46.19% female) aged ≥ 60 years of age. Depressive symptoms were measured using the 10-item Center for Epidemiological Studies Depression Scale (CES-D). Individuals' greenspace exposure was quantified using spatially and temporally resolved metrics, including monthly and annual averaged satellite-derived normalized difference vegetation index (NDVI) across multiple buffer distances (250 m to 2,000 m) centered at participants' home address. We also quantified exposure to blue-greenspace from a highly detailed land use and land cover dataset. A multivariable logistic regression model assessed the association between greenspace and blue-greenspace exposure and depressive symptoms, adjusting for age, sex, income, education, marital status, current smoking, alcohol status, medical conditions, temperature, crime rate, population density, and per capita park area.

RESULTS

We found a significant association between exposures to greenspace and blue-greenspace and depressive symptoms (CES-D cutoff ≥ 4) among older adults. After adjusting for confounding variables, the odds of depressive symptoms were significantly decreased by an IQR increment in residential exposure to greenspace [odds ratio (OR) = 0.67; 95% confidence interval (95% CI), 0.49 ~ 0.91] and blue-greenspace (OR = 0.59; 95% CI, 0.41 ~ 0.84) measured nearby their home address (i.e., as close as 250 m). When stratified by household income level, the association was only significant among low-income individuals. We also found temporal variation in the association between depressive symptoms and monthly NDVI-based greenspace exposure, in which the odds of depressive symptoms were the lowest for greenspace in cold months (i.e., January, February, and March).

CONCLUSIONS

Our findings suggest that neighborhood greenspace may serve as a protective factor against depression among older adults, but the benefits may depend on the spatial and temporal context. More investigation is needed to replicate our findings on the spatial and temporal variations of greenspace exposure metrics and their effects on depressive symptoms.

Assessing the impact of urban road transport development on haze pollution in the Yangtze River Delta region

The aim of this paper is to explore whether and how urban road transport (URT) development affects haze pollution. One of the innovations of this paper is that URT development is measured by road accessibility with novel digital elevation model datasets, which have been used by few scholars. The endogenous problem caused by revere causality issue in the relationship between URT development and haze pollution is also considered. Based on the panel data of prefecture-level cities of Yangtze River Delta (YRD) region in China from 2011 to 2018, this paper uses long-lagged values of URT development as the instrumental variable, employing the two-stage least squares (2SLS) method. The study shows that URT development leads to an increase of haze pollution. Moreover, mechanism tests based on moderating and mediating models support the finding that decreasing haze pollution resulted from better connection effects, while rising agglomeration effects tend to bring about increasing haze pollution, and the latter effect is larger in magnitude than the former. Current URT development may have long-term negative consequences for livability of YRD cities, and urban decision makers should reconsider the effectiveness of the current road transport investment and construction.

The use of Enhanced Vegetation Index for assessing access to different types of green space in epidemiological studies

BACKGROUND

Exposure to green space can protect against poor health through a variety of mechanisms. However, there is heterogeneity in methodological approaches to exposure assessments which makes creating effective policy recommendations challenging.

OBJECTIVE

Critically evaluate the use of a satellite-derived exposure metric, the Enhanced Vegetation Index (EVI), for assessing access to different types of green space in epidemiological studies.

METHODS

We used Landsat 5-8 (30 m resolution) to calculate average EVI for a 300 m radius surrounding 1.4 million households in Wales, UK for 2018. We calculated two additional measures using topographic vector data to represent access to green spaces within 300 m of household locations. The two topographic vector-based measures were total green space area stratified by type and average private garden size. We used linear regression models to test whether EVI could discriminate between publicly accessible and private green space and Pearson correlation to test associations between EVI and green space types.

RESULTS

Mean EVI for a 300 m radius surrounding households in Wales was 0.28 (IQR = 0.12). Total green space area and average private garden size were significantly positively associated with corresponding EVI measures (β = < 0.0001, 95% CI: 0.0000, 0.0000; β = 0.0001, 95% CI: 0.0001, 0.0001 respectively). In urban areas, as average garden size increases by 1 m2, EVI increases by 0.0002. Therefore, in urban areas, to see a 0.1 unit increase in EVI index score, garden size would need to increase by 500 m2. The very small β values represent no 'measurable real-world' associations. When stratified by type, we observed no strong associations between greenspace and EVI.

IMPACT

It is a widely implemented assumption in epidiological studies that an increase in EVI is equivalent to an increase in greenness and/or green space. We used linear regression models to test associations between EVI and potential sources of green reflectance at a neighbourhood level using satellite imagery from 2018. We compared EVI measures with a 'gold standard' vector-based dataset that defines publicly accessible and private green spaces. We found that EVI should be interpreted with care as a greater EVI score does not necessarily mean greater access to publicly available green spaces in the hyperlocal environment.

Do environmental attitudes and personal characteristics influence how people perceive their exposure to green spaces?

Background

This study explores the relationship between perceived and objective greenspace exposure, and how sociodemographic traits and environmental attitudes influence peoples' perceptions of greenspace.

Methods

We leveraged a cross-sectional survey on greenspace exposure among residents of Denver, CO that ran from November 2019 through April 2021. We measured objective greenspace using the average NDVI (normalized difference vegetation index), average percent vegetation, and median GVI (green view index) within 300, 500, and 1,000 m of participants' residences, and in participant-drawn polygons representing their neighborhoods. We measured perceived greenspace exposure using survey responses from questions about greenspace abundance, visibility, access, usage, and quality near participants' homes. We assessed relationships between perceived and objective greenspace measures using linear models. Then, we used latent class analysis to create perceived greenspace exposure classes, and used linear models to evaluate the relationship between these classes and sociodemographic and environmental attitude variables.

Results

We found that the relationship between perceived and objective measures (NDVI in the 300-meter buffer) was strongest for abundance (OR: 5.14, [4.0, 6.28]) and visibility (OR: 3.71, [2.58, 4.84]) compared to perceived access (OR: 2.17, [1.02, 3.32]), usage (OR: 2.28, [1.19, 3.37]), and quality (OR: 2.33, [1.25, 3.41]). In fully adjusted models, objective greenspace exposure and environmental attitudes predicted perceived greenspace exposure classes, but sociodemographic variables-other than age-did not.

Conclusion

Our work suggests that objective greenspace exposure is only one factor influencing peoples' perceived greenspace exposure, and that environmental attitude variables may play an additional role in shaping peoples' perceptions.

Green spaces and respiratory, cardiometabolic, and neurodevelopmental outcomes: An individual-participant data meta-analysis of >35.000 European children

Studies evaluating the benefits and risks of green spaces on children's health are scarce. The present study aimed to examine the associations between exposure to green spaces during pregnancy and early childhood with respiratory, cardiometabolic, and neurodevelopmental outcomes in school-age children. We performed an Individual-Participant Data (IPD) meta-analysis involving 35,000 children from ten European birth cohorts across eight countries. For each participant, we calculated residential Normalized Difference Vegetation Index (NDVI) within a 300 m buffer and the linear distance to green spaces (meters) during prenatal life and childhood. Multiple harmonized health outcomes were selected: asthma and wheezing, lung function, body mass index, diastolic and systolic blood pressure, non-verbal intelligence, internalizing and externalizing problems, and ADHD symptoms. We conducted a two-stage IPD meta-analysis and evaluated effect modification by socioeconomic status (SES) and sex. Between-study heterogeneity was assessed via random-effects meta-regression. Residential surrounding green spaces in childhood, not pregnancy, was associated with improved lung function, particularly higher FEV1 (β = 0.06; 95 %CI: 0.03, 0.09 I2 = 4.03 %, p < 0.001) and FVC (β = 0.07; 95 %CI: 0.04, 0.09 I2 = 0 %, p < 0.001) with a stronger association observed in females (p < 0.001). This association remained robust after multiple testing correction and did not change notably after adjusting for ambient air pollution. Increased distance to green spaces showed an association with lower FVC (β = -0.04; 95 %CI: -0.07, -0.02, I2 = 4.8, p = 0.001), with a stronger effect in children from higher SES backgrounds (p < 0.001). No consistent associations were found between green spaces and asthma, wheezing, cardiometabolic, or neurodevelopmental outcomes, with direction of effect varying across cohorts. Wheezing and neurodevelopmental outcomes showed high between-study heterogeneity, and the age at outcome assessment was only associated with heterogeneity in internalizing problems.. This large European meta-analysis suggests that childhood exposure to green spaces may lead to better lung function. Associations with other respiratory outcomes and selected cardiometabolic and neurodevelopmental outcomes remain inconclusive.

Multiple Environmental Exposures and the Development of Hypertension in a Prospective US-Based Cohort of Female Nurses: A Mixture Analysis

We investigated the independent and joint associations between multiple environmental exposures and incident hypertension in a US nationwide prospective cohort of women: the Nurses' Health Study II. We followed 107,532 nonhypertensive participants from 1989 to diagnosis of hypertension, loss to follow-up, death, or end of follow-up in June 2019. We applied Cox proportional hazards models to assess associations of incident hypertension with time-varying residential exposure to air pollution, noise, surrounding greenness, temperature, and neighborhood socioeconomic status (nSES), adjusting for potential confounders and coexposures. We evaluated the joint association of simultaneous exposure using quantile g-computation. We observed 38,175 hypertension cases over 2,062,109 person-years. Increased hypertension incidence was consistently associated with lower nSES and higher levels of fine particles (PM2.5) and nighttime noise exposures: hazard ratio (HRs) and 95% confidence intervals (CIs) of 1.06 (1.04, 1.08), 1.04 (1.01, 1.07), and 1.01 (1.00, 1.03), respectively, per interquartile range change. Joint HR for a one-quartile change in simultaneous exposure to the mixture was 1.05 (95% CI: 1.02, 1.09), assuming additivity, or 1.13 (95% CI: 1.06, 1.20), considering potential interactions within the mixture. Hypertension prevention should focus on enhancing nSES and reducing PM2.5 and noise levels, recognizing that reducing the overall exposures may yield additional benefits.

Urban heatwave, green spaces, and mental health: A review based on environmental health risk assessment framework

Utilizing the framework of environmental health risk assessment and healing, the article reviews the effectiveness and potential of green space systems in mitigating the impact of high temperatures, promoting mental health, and improving the risk characteristics of high-temperature heat waves. We utilized CiteSpace software to conduct a time-zone analysis of the relationship between heatwaves, green spaces, and health using clustered data from 2001 to 2023. This study evaluates the role of green space systems in mitigating high temperatures and enhancing mental health within the environmental health risk assessment framework. Using CiteSpace software, we analyzed literature from 2001 to 2023, focusing on the interactions among heatwaves, green spaces, and health. Our results indicate that most existing research concentrates on hazard identification, with insufficient exploration of the dose-response relationships between green spaces and temperature reduction. Quantitative studies on green space design and spatial optimization are scarce, and guidance on effective configurations remains limited. Additionally, the health impacts of heatwaves vary by region, with a noticeable imbalance in research focus; Asia and Africa, in particular, are underrepresented in studies addressing heatwave effects. We conclude that effective mitigation strategies require: (1) a comprehensive environmental health risk assessment framework that integrates advanced methods like big data analysis and geospatial simulations to improve green space planning and design; (2) further theoretical exploration into the mechanisms by which green spaces regulate temperature and mental health, including detailed analysis of spatiotemporal patterns and the functional optimization of green space structures; and (3) the development of robust parameterized design guidance based on specific therapeutic dosages (green space stimulus) to optimize configurations and enhance the effectiveness of green spaces in mitigating adverse mental health impacts from deteriorating thermal environments. Future research should prioritize underrepresented regions, focusing on exposure levels, dose-response relationships, and high-temperature warning systems while fostering multidisciplinary collaboration to develop effective urban planning and climate adaptation strategies.

Socioeconomic disparities and green space associated with myopia among Chinese school-aged students: A population-based cohort study

Background

There is increasing evidence on the link between environmental factors and myopia in children and adolescents, yet with inconsistent conclusions. We investigated the associations between socioeconomic inequalities and green space with myopia in school-aged students participating in the Tianjin Child and Adolescent Research of Eye (TCARE) study.

Methods

We obtained data from a population-based dynamic cohort study conducted in Tianjin, China, in 2021 and followed up in 2022. We included 1 245 271 participants from 16 districts with an average age of 11.6 years (standard deviation = 3.3) in our analysis. We synthesized their area-level SES through a prediction model that combined economic, educational, and health care variables and assessed the greenness levels surrounding the school using the Normalized Difference Vegetation Index (NDVI) based on data obtained through satellite remote sensing. We performed generalised linear mixed effects analyses for each myopia outcome separately, with adjustments for students' sex, years of education completed, and the school's geographical location.

Results

We observed that students living in low SES areas had the highest prevalence of myopia (60.7%) in the last screening in 2022, as well as a higher incidence of one-year myopia (26.4%) compared to those residing in middle SES areas (22.7%). With a 0.1 increase in the 250, 500, and 1000 m buffer NDVI, the prevalence of myopia dropped by 6.3% (odds ratio (OR) = 0.937; 95% confidence interval (CI) = 0.915, 0.960), 7.7% (OR = 0.923; 95% CI = 0.900, 0.946), and 8.7% (OR = 0.913; 95% CI = 0.889, 0.937), respectively. The interaction analysis showed that low SES and low greenness exacerbate the prevalence of myopia. Findings from longitudinal analyses consistently demonstrated a correlation between higher values of NDVI and a slower progression of myopia. These findings remained robust across sensitivity analyses, including for variables on parental myopia and students' behaviors.

Conclusions

Exposure to green spaces could play a crucial role in slowing the progression of myopia among school-aged students. Myopia control policies should prioritise young populations residing in low SES areas with limited access to green spaces, as they face the highest potential risks.

Greenness, air pollution, and temperature exposure effects in predicting premature mortality and morbidity: A small-area study using spatial random forest model

BACKGROUND

Although studies have provided negative impacts of air pollution, heat or cold exposure on mortality and morbidity, and positive effects of increased greenness on reducing them, a few studies have focused on exploring combined and synergetic effects of these exposures in predicting these health outcomes, and most had ignored the spatial autocorrelation in analyzing their health effects. This study aims to investigate the health effects of air pollution, greenness, and temperature exposure on premature mortality and morbidity within a spatial machine-learning modeling framework.

METHODS

Years of potential life lost reflecting premature mortality and comparative illness and disability ratio reflecting chronic morbidity from 1673 small areas covering Greater Manchester for the year 2008-2013 obtained. Average annual levels of NO2 concentration, normalized difference vegetation index (NDVI) representing greenness, and annual average air temperature were utilized to assess exposure in each area. These exposures were linked to health outcomes using non-spatial and spatial random forest (RF) models while accounting for spatial autocorrelation.

RESULTS

Spatial-RF models provided the best predictive accuracy when accounted for spatial autocorrelation. Among the exposures considered, air pollution emerged as the most influential in predicting mortality and morbidity, followed by NDVI and temperature exposure. Nonlinear exposure-response relations were observed, and interactions between exposures illustrated specific ranges or sweet and sour spots of exposure thresholds where combined effects either exacerbate or moderate health conditions.

CONCLUSION

Air pollution exposure had a greater negative impact on health compared to greenness and temperature exposure. Combined exposure effects may indicate the highest influence of premature mortality and morbidity burden.

Having a tree in front of one's home is associated with GREATER subjective wellbeing in adult residents in Melbourne, Australia, and Toronto, Canada

While urban trees can be important determinants of human health and wellbeing in world cities, the specific influence of nearby urban trees upon human wellbeing has not been adequately explored. While many studies have associated urban greenery abundance with wellbeing scores, many measures of urban greenery do not specify the type of vegetation or the impact of co-location. Here we fill this gap by associating self-reported measures of the presence of nearby trees (tree in front of one's home) with validated subjective wellbeing (SWB) scores. We also tested for the mediating role of what people thought about trees and nature, with a focus on the values people associate with urban trees and nature relatedness (NR). We used electronic panel survey data based on a demographic and geographical representative sample of more than 3400 residents living in Toronto, Canada, and Melbourne, Australia. We analysed these data using regression-based mediation and path analyses. We found that having a tree in front of one's home was strongly and positively associated with SWB scores in both cities with similar results (Melbourne, β = 0.17, p < 0.05; Toronto, β = 0.18, p < 0.05), while accounting for NR, values associated with urban trees, and demographics (e.g., age, education, home ownership). The mediating role of NR and values was small. The specific pathways of association between tree in front of one's home, SWB, NR, and values, varied by city, when accounting for demographics. We discuss how increasing the abundance of nearby urban trees in cities may also increase human wellbeing.

Impact of "blue-green diet" on human health and wellbeing: A systematic review of potential determinants in shaping the effectiveness of blue-green infrastructure (BGI) in urban settings

Discourses concerning the potential health benefits of blue-green infrastructure (BGI) have gained momentum, highlighting its positive influence on human health and wellbeing. While studies have explored the concept of "Nature Pyramid" and the role of exposure to natural environments in promoting health, the role of water elements remains underexplored. Rooted in this concept, this study proposed a notion of "blue-green diet" as a framework to understand the intricate mechanisms and determinants of optimal blue-green exposure. Understanding the relationship between these determinants and their health-related impacts can facilitate the enhancement of BGI design, leading to greater effectiveness in promoting health and wellbeing and supporting sustainable urban development strategies. To enhance the comprehension of the "blue-green diet", this study conducted a systematic literature review to grasp the underlying mechanisms behind its beneficial effects, focusing on two key determinants of "blue-green diet", which are also derived from the concept of the "Nature Pyramid": (1) the type of BGI and (2) the mode of interaction with and within BGIs. Under the search of BGI's overall health impacts, this study selected 54 journal publications concerning BGI's type and interaction mode from Web of Science and Scopus since 2010. The review revealed significant disparities in the health benefits provided by different types of BGI (in terms of artificial extent and scale) and between active and passive interaction modes. It examines how to balance natural and artificial elements for enhancing the benefits of BGI and discusses the attributes of BGI that encourage diverse and meaningful interaction patterns. These efforts collectively aim to optimize BGI design and planning, increase its capacity to promote health, and extend its benefits to a wider range of individuals. Future research should encompass a broader spectrum of determinants, such as diverse BGI settings, visit frequency and duration, and user's social-cultural backgrounds.

Quantitative evaluation of urban green exposure and its impact on human health: A case study on the 3-30-300 green space rule

BACKGROUND AND AIMS

Urban green spaces offer various health benefits, yet the impact of comprehensive green exposure criteria on multidimensional health remains unclear. The 3-30-300 green space rule represents the green exposure indicators with specific thresholds. This study aims to quantitatively evaluate urban green exposure in cities and can support investigation of its relationship with human health.

METHODS

We conducted a cross-sectional study based on 902 investigated individuals in 261 residential locations aged 11-95 years from Xiamen City, China. 3-30-300 green exposure was calculated using field surveys, GIS, and Baidu Maps Application Programming Interface (API). Physical health data was based on Occupational Stress Indicator (OSI)-2. Mental health was from the 12-item General Health Questionnaire (GHQ-12). Social health was from a self-constructed evaluation questionnaire. Statistical analyses were conducted using Geographically Weighted Regression and Geographically Weighted Logistic Regression for global and local effects on green exposure and multidimensional health.

RESULT

Among the investigated individuals, only 3.55 % (32/902) fully meet the 3-30-300 rule in Xiamen. Global results show that individuals achieved at least 30 % vegetation coverage (Yes) is associated with better physical (β: 0.76, p < 0.01) and social (β: 0.5, p < 0.01) health. GWLR global results indicate that individuals can "see at least 3 trees from home" meeting one (OR = 0.46, 95%CI: 0.25-0.86, p < 0.05) or two (OR = 0.41, 95%CI: 0.22,0.78, p < 0.01; OR = 0.24, 95%CI: 0.07-0.77, p < 0.05) 3-30-300 rule components are significantly associated with reduced medical visits and hospitalizations refer to not met these criterias. In the GWR local analysis, achieved 30 % vegetation cover is significantly related to improved social health at all locations. Meeting any two indicators also contribute to improved social health (n = 511, β: 0.46-0.51, P < 0.05).

CONCLUSION

Green exposure indicators based on the 3-30-300 rule guiding healthy urban green space development. We observed multidimensional health benefits when 1/3 or 2/3 of the indicators were met.

Impact of green space and built environment on metabolic syndrome: A systematic review with meta-analysis

Metabolic Syndrome presents a significant public health challenge associated with an increased risk of noncommunicable diseases such as cardiovascular conditions. Evidence shows that green spaces and the built environment may influence metabolic syndrome. We conducted a systematic review and meta-analysis of observational studies published through August 30, 2023, examining the association of green space and built environment with metabolic syndrome. A quality assessment of the included studies was conducted using the Office of Health Assessment and Translation (OHAT) tool. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) assessment was used to evaluate the overall quality of evidence. Our search retrieved 18 studies that met the inclusion criteria and were included in our review. Most were from China (n = 5) and the USA (n = 5), and most used a cross-sectional study design (n = 8). Nine studies (50 %) reported only green space exposures, seven (39 %) reported only built environment exposures, and two (11 %) reported both built environment and green space exposures. Studies reported diverse definitions of green space and the built environment, such as availability, accessibility, and quality, particularly around participants' homes. The outcomes focused on metabolic syndrome; however, studies applied different definitions of metabolic syndrome. Meta-analysis results showed that an increase in normalized difference vegetation index (NDVI) within a 500-m buffer was associated with a lower risk of metabolic syndrome (odds ratio [OR] = 0.90, 95%CI = 0.87-0.93, I2 = 22.3 %, n = 4). A substantial number of studies detected bias for exposure classification and residual confounding. Overall, the extant literature shows a 'limited' strength of evidence for green space protecting against metabolic syndrome and an 'inadequate' strength of evidence for the built environment associated with metabolic syndrome. Studies with more robust study designs, better controlled confounding factors, and stronger exposure measures are needed to understand better what types of green spaces and built environment features influence metabolic syndrome.

Impacts of social deprivation on mortality and protective effects of greenness exposure in Hong Kong, 1999-2018: A spatiotemporal perspective

Addressing health inequality is crucial for fostering healthy city development. However, there is a dearth of literature simultaneously investigating the effects of social deprivation and greenness exposure on mortality risks, as well as how greenness exposure may mitigate the adverse effect of social deprivation on mortality risks from a spatiotemporal perspective. Drawing on socioeconomic, remote sensing, and mortality record data, this study presents spatiotemporal patterns of social deprivation, population weighted greenness exposure, and all-cause and cause-specific mortality in Hong Kong. A Bayesian regression model was applied to investigate the impacts of social deprivation and greenness exposure on mortality and examine how socioeconomic inequalities in mortality may vary across areas with different greenness levels in Hong Kong from 1999 to 2018. We observed a decline in social deprivation (0.67-0.56), and an increase in greenness exposure (0.34-0.41) in Hong Kong during 1999-2018. Areas with high mortality gradually clustered in the Kowloon Peninsula and the northern regions of Hong Kong Island. Adverse impacts of social deprivation on all-cause mortality weakened in recent years (RR from 2009 to 2013: 1.103, 95%CI: 1.051-1.159, RR from 2014 to 2018: 1.041 95%CI: 0.950-1.139), while the protective impacts of greenness exposure consistently strengthened (RR from 1999 to 2003: 0.903, 95%CI: 0.827-0.984, RR from 2014 to 2018: 0.859, 95%CI: 0.763-0.965). Moreover, the adverse effects of social deprivation on mortality risks were found to be higher in areas with lower greenness exposure. These findings provide evidence of associations between social deprivation, greenness exposure, and mortality risks in Hong Kong over the past decades, and highlight the potential of greenness exposure to mitigate health inequalities. Our study provides valuable implications for policymakers to develop a healthy city.

Individual and Neighborhood Level Predictors of Children's Exposure to Residential Greenspace

Inequities in urban greenspace have been identified, though patterns by race and socioeconomic status vary across US settings. We estimated the magnitude of the relationship between a broad mixture of neighborhood-level factors and residential greenspace using weighted quantile sum (WQS) regression, and compared predictive models of greenspace using only neighborhood-level, only individual-level, or multi-level predictors. Greenspace measures included the Normalized Difference Vegetation Index (NDVI), tree canopy, and proximity of the nearest park, for residential locations in Shelby County, Tennessee of children in the CANDLE cohort. Neighborhood measures include socioeconomic and education resources, as well as racial composition and racial residential segregation. In this sample of 1012 mother-child dyads, neighborhood factors were associated with higher NDVI and tree canopy (0.021 unit higher NDVI [95% CI: 0.014, 0.028] per quintile increase in WQS index); homeownership rate, proximity of and enrollment at early childhood education centers, and racial composition, were highly weighted in the WQS index. In models constrained in the opposite direction (0.028 unit lower NDVI [95% CI: - 0.036, - 0.020]), high school graduation rate and teacher experience were highly weighted. In prediction models, adding individual-level predictors to the suite of neighborhood characteristics did not meaningfully improve prediction accuracy for greenspace measures. Our findings highlight disparities in greenspace for families by neighborhood socioeconomic and early education factors, and by race, suggesting several neighborhood indicators for consideration both as potential confounders in studies of greenspace and pediatric health as well as in the development of policies and programs to improve equity in greenspace access.

A Review on Recent Deep Learning-Based Semantic Segmentation for Urban Greenness Measurement

Accurate urban green space (UGS) measurement has become crucial for landscape analysis. This paper reviews the recent technological breakthroughs in deep learning (DL)-based semantic segmentation, emphasizing efficient landscape analysis, and integrating greenness measurements. It explores quantitative greenness measures applied through semantic segmentation, categorized into the plan view- and the perspective view-based methods, like the Land Class Classification (LCC) with green objects and the Green View Index (GVI) based on street photographs. This review navigates from traditional to modern DL-based semantic segmentation models, illuminating the evolution of the urban greenness measures and segmentation tasks for advanced landscape analysis. It also presents the typical performance metrics and explores public datasets for constructing these measures. The results show that accurate (semantic) segmentation is inevitable not only for fine-grained greenness measures but also for the qualitative evaluation of landscape analyses for planning amidst the incomplete explainability of the DL model. Also, the unsupervised domain adaptation (UDA) in aerial images is addressed to overcome the scale changes and lack of labeled data for fine-grained greenness measures. This review contributes to helping researchers understand the recent breakthroughs in DL-based segmentation technology for challenging topics in UGS research.

Current methodologies of greenspace exposure and mental health research-a scoping review

Introduction

Greenspaces can provide an important resource for human mental health. A growing body of literature investigates the interaction and the influence of diverse greenspace exposures. In order to gain a comprehensive understanding of the complex connection between greenspace and mental health, a variety of perspectives and methodological combinations are needed. The aim of this review is to assess the current methodologies researching greenspace and mental health.

Methods

A scoping review was conducted. Four electronic databases (Pubmed, Embase, PsycInfo, Web of Science) were searched for relevant studies. A wide range of greenspace and mental health keywords were included to provide a comprehensive representation of the body of research. Relevant information on publication characteristics, types of greenspaces, mental health outcomes, and measurements of greenspace exposure and mental health was extracted and assessed.

Results

338 studies were included. The included studies encompassed a multitude of methods, as well as outcomes for both greenspace and mental health. 28 combinations were found between seven categories each for greenspace and mental health assessment. Some pairings such as geoinformation systems for greenspace assessment and questionnaires investigating mental health were used much more frequently than others, implying possible research gaps. Furthermore, we identified problems and inconsistences in reporting of greenspace types and mental health outcomes.

Discussion

The identified methodological variety is a potential for researching the complex connections between greenspace and mental health. Commonly used combinations can provide important insights. However, future research needs to emphasize other perspectives in order to understand how to create living environments with mental health benefits. For this purpose, interdisciplinary research is necessary.

The economics of nature's healing touch: A systematic review and conceptual framework of green space, pharmaceutical prescriptions, and healthcare expenditure associations

Green spaces play a crucial role in promoting sustainable and healthy lives. Recent evidence shows that green space also may reduce the need for healthcare, prescription medications, and associated costs. This systematic review provides the first comprehensive assessment of the available literature examining green space exposure and its associations with healthcare prescriptions and expenditures. We applied Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines to search MEDLINE, Scopus, and Web of Science for observational studies published in English through May 6, 2023. A quality assessment of the included studies was conducted using the Office of Health Assessment and Translation (OHAT) tool, and the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) assessment was used to evaluate the overall quality of evidence. Our search retrieved 26 studies that met the inclusion criteria and were included in our review. Among these, 20 studies (77 % of the total) showed beneficial associations of green space exposure with healthcare prescriptions or expenditures. However, most studies had risks of bias, and the overall strength of evidence for both outcomes was limited. Based on our findings and related bodies of literature, we present a conceptual framework to explain the possible associations and complex mechanisms underlying green space and healthcare outcomes. The framework differs from existing green space and health models by including upstream factors related to healthcare access (i.e., rurality and socioeconomic status), which may flip the direction of associations. Additional research with lower risks of bias is necessary to validate this framework and better understand the potential for green space to reduce healthcare prescriptions and expenditures.

Critical windows of greenness exposure during preconception and gestational periods in association with birthweight outcomes

Few studies have examined the association between greenness exposure and birth outcomes. This study aims to identify critical exposure time windows during preconception and pregnancy for the association between greenness exposure and birth weight. A cohort of 13 890 pregnant women and newborns in Shanghai, China from 2016-2019 were included in the study. We assessed greenness exposure using Normalized Difference Vegetation Index (NDVI) during the preconception and gestational periods, and evaluated the association with term birthweight, birthweight z-score, small-for-gestational age, and large-for-gestational age using linear and logistic regressions adjusting for key maternal and newborn covariates. Ambient temperature, relative humidity, ambient levels of fine particles (PM2.5) and nitrogen dioxide (NO2) assessed during the same period were adjusted for as sensitivity analyses. Furthermore, we explored the potential different effects by urbanicity and park accessibility through stratified analysis. We found that higher greenness exposure at the second trimester of pregnancy and averaged exposure during the entire pregnancy were associated with higher birthweight and birthweight Z-score. Specifically, a 0.1 unit increase in second trimester averaged NDVI value was associated with an increase in birthweight of 10.2 g (95% CI: 1.8-18.5 g) and in birthweight Z-score of 0.024 (0.003-0.045). A 0.1 unit increase in an averaged NDVI during the entire pregnancy was associated with 10.1 g (95% CI: 1.0-19.2 g) increase in birthweight and 0.025 (0.001-0.048) increase in birthweight Z-score. Moreover, the associations were larger in effect size among urban residents than suburban residents and among residents without park accessibility within 500 m compared to those with park accessibility within 500 m. Our findings suggest that increased greenness exposure, particularly during the second trimester, may be beneficial to birth weight in a metropolitan area.

How does multiscale greenspace exposure affect human health? Evidence from urban parks in the central city of Beijing

While the health benefits of exposure to urban greenspace have been widely discussed at different spatial scales, the comprehensive health effects of multiscale greenspace exposure are far from understood. There is a lack of quantified evidence when conducting cost-effective greenspace management practices for promoting human health and well-being. This study proposed a conceptual model that links objective and subjective greenspace exposure metrics at different spatial scales with self-rated health of residents. The model attempted to deconstruct and explore the associations between multiscale greenspace exposure and human health, and a cross-sectional study was conducted to examine the model. Taking urban parks in the central city of Beijing as case study area, the objective greenspace exposure metrics at both the site and subdistrict scales were spatial explicitly assessed, and the subjective exposure metrics and self-rated health status of 1017 respondents were obtained through questionnaire survey and spatial positioning. The results of multiple regression analyses and path analyses suggested that greenspace exposure metrics at both site and subdistrict scales were significantly associated with the respondents' self-rated health status, with the exposure metrics at the site scale being more important than those at the subdistrict scale in affecting human health. The contribution of urban parks to self-rated physical and mental health of respondents varied across spatial scales. Specifically, the aesthetic value of urban parks at site scale contributed the most to mental health by promoting respondents' resting behaviors in urban parks, and the density of urban parks at subdistrict scale had the most significant effects on self-rated physical health by increasing the usage frequency of urban parks. Findings of this study can contribute to understanding the complex associations between urban greenspace and human health from a multiscale perspective, and are also expected to provide quantified information for health-oriented urban greenspace planning and management practices.

Associations of residential green space with internalizing and externalizing behavior in early childhood

BACKGROUND

Green space exposures may promote child mental health and well-being across multiple domains and stages of development. The aim of this study was to investigate associations between residential green space exposures and child mental and behavioral health at age 4-6 years.

METHODS

Children's internalizing and externalizing behaviors in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) cohort in Shelby County, Tennessee, were parent-reported on the Child Behavior Checklist (CBCL). We examined three exposures-residential surrounding greenness calculated as the Normalized Difference Vegetation Index (NDVI), tree cover, and park proximity-averaged across the residential history for the year prior to outcome assessment. Linear regression models were adjusted for individual, household, and neighborhood-level confounders across multiple domains. Effect modification by neighborhood socioeconomic conditions was explored using multiplicative interaction terms.

RESULTS

Children were on average 4.2 years (range 3.8-6.0) at outcome assessment. Among CANDLE mothers, 65% self-identified as Black, 29% as White, and 6% as another or multiple races; 41% had at least a college degree. Higher residential surrounding greenness was associated with lower internalizing behavior scores (-0.66 per 0.1 unit higher NDVI; 95% CI: -1.26, -0.07) in fully-adjusted models. The association between tree cover and internalizing behavior was in the hypothesized direction but confidence intervals included the null (-0.29 per 10% higher tree cover; 95% CI: -0.62, 0.04). No associations were observed between park proximity and internalizing behavior. We did not find any associations with externalizing behaviors or the attention problems subscale. Estimates were larger in neighborhoods with lower socioeconomic opportunity, but interaction terms were not statistically significant.

CONCLUSIONS

Our findings add to the accumulating evidence of the importance of residential green space for the prevention of internalizing problems among young children. This research suggests the prioritization of urban green spaces as a resource for child mental health.

Anthropogenic impacts on urban blue space and its reciprocal effect on human and socio-ecological health

Quantifying anthropogenic impacts on blue space (BS) and its effect on human and socio-ecological health was least explored. The present study aimed to do this in reference to the urban BS transformation scenario of Eastern India. To measure BS transformation, Landsat image-based water indices were run from 1990 to 2021. Anthropogenic impact score (AIS) and 7 components scores of 78 selected BS on 70 parameters related data driven from the field. Total 345 respondents were taken for human and socio-ecological health assessment. For this, depression (DEP), anxiety (ANX), stress (STR), physical activities (PA), social capital (SC), therapeutic landscape (TL) and environment building (EB) parameters were taken. The result exhibited that BS was reduced. About 50% of urban core BS was reported highly impacted. Human and socio-ecological health was identified as good in proximity to BS, but it was observed better in the cases of larger peripheral BS. AIS on BS was found to be positively associated with mental health (0.47-0.63) and negatively associated with PA, SC, TL and EB (-0.50 to -0.90). Standard residual in ordinary least square was reported low (-1.5 to 1.5) in 95% BS. Therefore, BS health restoration and management is crucial for sustaining the living environment.

The relation between proximity to and characteristics of green spaces to physical activity and health: A multi-dimensional sensitivity analysis in four European cities

INTRODUCTION

Non-communicable diseases are the global disease burden of our time, with physical inactivity identified as one major risk factor. Green spaces are associated with increased physical activity of nearby residents. But there are still gaps in understanding which proximity and what characteristics of green spaces can trigger physical activity. This study aims to unveil these differences with a rigorous sensitivity analysis.

METHODS

We gathered data on self-reported health and physical activity from 1365 participants in selected neighbourhoods in Porto, Nantes, Sofia, and Høje-Taastrup. Spatial data were retrieved from OpenStreetMap. We followed the PRIGSHARE guidelines to control for bias. Around the residential addresses, we generated seven different green space indicators for 15 distances (100-1500 m) using the AID-PRIGSHARE tool. We then analysed each of these 105 green space indicators together with physical activity and health in 105 adjusted structural equation models.

RESULTS

Green space accessibility and green space uses indicators showed a pattern of significant positive associations to physical activity and indirect to health at distances of 1100 m or less, with a peak at 600 m for most indicators. Greenness in close proximity (100 m) had significant positive effects on physical activity and indirect effects on health. Surrounding greenness showed positive direct effects on health at 500-1100 m and so do green corridors in 800 m network distance. In contrast, a high quantity of green space uses, and surrounding greenness measured in a larger radius (1100-1500 m) showed a negative relationship with physical activity and indirect health effects.

CONCLUSIONS

Our results provide insight into how green space characteristics can influence health at different scales, with important implications for urban planners on how to integrate accessible green spaces into urban structures and public health decision-makers on the ability of green spaces to combat physical inactivity.

Measuring the 3-30-300 rule to help cities meet nature access thresholds

The 3-30-300 rule offers benchmarks for cities to promote equitable nature access. It dictates that individuals should see three trees from their dwelling, have 30 % tree canopy in their neighborhood, and live within 300 m of a high-quality green space. Implementing this demands thorough measurement, monitoring, and evaluation methods, yet little guidance is currently available to pursue these actions. To overcome this gap, we employed an expert-based consensus approach to review the available ways to measure 3-30-300 as well as each measure's strengths and weaknesses. We described seven relevant data and processes: vegetation indices, street level analyses, tree inventories, questionnaires, window view analyses, land cover maps, and green space maps. Based on the reviewed strengths and weaknesses of each measure, we presented a suitability matrix to link recommended measures with each component of the rule. These recommendations included surveys and window-view analyses for the '3 component', high-resolution land cover maps for the '30 component', and green space maps with network analyses for the '300 component'. These methods, responsive to local situations and resources, not only implement the 3-30-300 rule but foster broader dialogue on local desires and requirements. Consequently, these techniques can guide strategic investments in urban greening for health, equity, biodiversity, and climate adaptation.

Association between greenspace exposure and suicide-related outcomes across the lifespan: A systematic review

A growing number of studies have linked greenspace exposure to suicide, but findings are inconsistent. We conducted a systematic review on the associations between greenspace exposure and suicide-related outcomes (namely, suicide mortality, self-harm, and suicidal ideation) up until January 6, 2023. We used the Mixed Methods Appraisal Tool (or MMAT) to assess the quality of the included studies. In total, 23 studies met our inclusion criteria, consisting of 14 ecological, four cross-sectional, three longitudinal, and two experimental studies. Most studies were published in 2022 and conducted in Europe (n = 10), Asia (n = 7), and North America (n = 5), with one worldwide analysis. Various indicators were used to assess greenspace exposure including objective measures (e.g., level of surrounding greenness, quantity, structural features, tree canopy coverage), and greenspace use (e.g., duration and frequency). Suicide mortality was the most studied outcome (n = 14). Quality assessment showed that most (87 %) of the included observational studies used representative samples. Protective associations of exposure to greenspace were reported for suicide mortality (9/14 or 64 %), self-harm (n = 3/5 or 60 %) and suicidal ideation (n = 4/6 or 67 %), with nine or 36 % studies reporting no association. Most of the included studies adjusted for key covariates such as age, sex, and socioeconomic status at various aggregate levels (e.g., household, city). For greenspace exposure and suicide mortality, studies stratified by sex (n = 10) showed larger protective associations for females (n = 7) than for males (n = 4). However, the included studies showed high heterogeneity in terms of exposure indicators and greenspace definitions. Experimental studies and studies using youth samples were rare. While more research is warranted, preliminary findings suggest protective associations between greenspace exposure and suicide-related outcomes.

Geographic uncertainties in external exposome studies: A multi-scale approach to reduce exposure misclassification

BACKGROUND

Many studies on environment-health associations have emphasized that the selected buffer size (i.e., the scale of the geographic context when exposures are assigned at people's address location) may affect estimated effect sizes. However, there is limited methodological progress in addressing these buffer size-related uncertainties.

AIM

We aimed to 1) develop a statistical multi-scale approach to address buffer-related scale effects in cohort studies, and 2) investigate how environment-health associations differ between our multi-scale approach and ad hoc selected buffer sizes.

METHODS

We used lacunarity analyses to determine the largest meaningful buffer size for multiple high-resolution exposure surfaces (i.e., fine particulate matter [PM2.5], noise, and the normalized difference vegetation index [NDVI]). Exposures were linked to 7.7 million Dutch adults at their home addresses. We assigned exposure estimates based on buffers with fine-grained distance increments until the lacunarity-based upper limit was reached. Bayesian Cox model averaging addressed geographic uncertainties in the estimated exposure effect sizes within the exposure-specific upper buffer limits on mortality. Z-tests assessed statistical differences between averaged effect sizes and those obtained through pre-selected 100, 300, 1200, and 1500 m buffers.

RESULTS

The estimated lacunarity curves suggested exposure-specific upper buffer size limits; the largest was for NDVI (960 m), followed by noise (910 m) and PM2.5 (450 m). We recorded 845,229 deaths over eight years of follow-up. Our multi-scale approach indicated that higher values of NDVI were health-protectively associated with mortality risk (hazard ratio [HR]: 0.917, 95 % confidence interval [CI]: 0.886-0.948). Increased noise exposure was associated with an increased risk of mortality (HR: 1.003, 95 % CI: 1.002-1.003), while PM2.5 showed null associations (HR:0.998, 95 % CI: 0.997-1.000). Effect sizes of NDVI and noise differed significantly across the averaged and prespecified buffers (p < 0.05).

CONCLUSIONS

Geographic uncertainties in residential-based exposure assessments may obscure environment-health associations or risk spurious ones. Our multi-scale approach produced more consistent effect estimates and mitigated contextual uncertainties.