Residential urban greenspace and hypertension: A comparative study in two European cities

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.

Chronic impacts of natural infrastructure on the physical and psychological health of university students during and after COVID-19: a case study of Chengdu, China

Introduction

The COVID-19 pandemic has underscored the health benefits of green spaces, yet research on how specific elements of natural infrastructure affect well-being during the pandemic has been limited.

Methods

This study, conducted at Sichuan Agricultural University with 300 students in 2022, investigated how urban natural infrastructure impacts physical and psychological well-being during the pandemic. Different aspects of natural infrastructure, such as thermal comfort, air quality (negative ion concentration), and noise and light levels, varied in their positive effects on students' health.

Results

The findings revealed that 65.6% of university students felt reduced stress when engaging with outdoor spaces, and 72.8% of them renewed recognized the therapeutic value of nature.

Discussion

The study emphasizes the importance of incorporating natural elements into urban planning to enhance outdoor activity and well-being, especially in post-pandemic settings. Recommendations are provided for future urban design to address the therapeutic needs of specific populations.

Effects of forest bathing (Shinrin-yoku) in stressed people

Aim

This study aims to explore the physiological effect of forest bathing on stress management.

Methods

A total of 29 volunteers participated in this pre-post design, which lacked a control group. Several physiological parameters were recorded, including heart rate (HR), heart rate variability (HRV), electrodermal activity (EDA), blood pressure (BP), immunoglobulin A (IGA), and salivary cortisol (sCort). Additionally, the Perceived Stress Scale (PSS-10) was administered before forest exposure. Measurements were taken before and after participants spent 2 days fully immersed in a forest environment. To further assess stress management, participants completed a Mental Arithmetic Task (MAT) before and after forest immersion, during which EDA, HRV, and HR were monitored using an Empatica E4 wristband. Measurements were taken at baseline, during MAT, and afterward (recovery).

Results

Participants exhibited moderate perceived stress levels before forest immersion (mean PSS-10 = 21.22, SD = 3.78). Post-forest exposure, there was a significant decrease in sCort (p < 0.05) and EDA (p < 0.001), while HRV increased (p < 0.001), and diastolic blood pressure rose (p < 0.05). ANOVA results from the MAT showed a significant increase in parasympathetic activity across all conditions post-immersion (p < 0.05), except during recovery, while EDA decreased in all conditions post-forest exposure (p < 0.05).

Conclusion

Shinrin-yoku significantly improved stress management at a physiological level and could be a valuable intervention for individuals experiencing stress. However, longitudinal studies with a control group are necessary to determine whether these effects are sustained over time. Nonetheless, this study highlights the potential benefits of forest immersion for stress reduction by enhancing sympathovagal balance and the adaptability of the stress response system.

Association of greenspace with hypertension in adult: a systematic review and meta-analysis of epidemiological studies

BACKGROUND

Several studies have investigated the relationship of greenspace with blood pressure (BP) and hypertension, but the results were inconsistent. We aimed to assess the relationship of greenspace with BP/hypertension.

METHODS

We searched PubMed, Embase and Web of Science on greenspace and BP/hypertension published before 5 April 2023. The methodological quality and risk of bias were evaluated.

RESULTS

Twenty-seven articles were included. Our results suggested that higher normalized difference vegetation index (NDVI) was associated with lower odds of hypertension and levels of SBP [for every 10% increase of NDVI 500-m and NDVI 1000-m, the ORs were 0.95 (95% CI: 0.90-0.99) and 0.95 (95% CI: 0.90-0.99), the ꞵwas -1.32 (95% CI: -2.18, -0.45) and -1.41 (95% CI: -2.57, -0.25), respectively].

CONCLUSION

This study indicated that higher exposure to greenspace might be associated with lower levels of BP and risk of hypertension. Increase green spaces should be regarded as an important public health intervention..

The impact of short-term exposure to meteorological factors on the risk of death from hypertension and its major complications: a time series analysis based on Hefei, China

OBJECTIVES

This study aimed to reveal the short-term impact of meteorological factors on the mortality risk in hypertensive patients, providing a scientific foundation for formulating pertinent prevention and control policies.

METHODS

In this research, meteorological factor data and daily death data of hypertensive patients in Hefei City from 2015 to 2018 were integrated. Time series analysis was performed using distributed lag nonlinear model (DLNM) and generalized additive model (GAM). Furthermore, we conducted stratified analysis based on gender and age. Relative risk (RR) combined with 95% confidence interval (95% CI) was used to represent the mortality risk of single day and cumulative day in hypertensive patients.

RESULTS

Single-day lag results indicated that high daily mean temperature (T mean) (75th percentile, 24.9 °C) and low diurnal temperature range (DTR) (25th percentile, 4.20 °C) levels were identified as risk factors for death in hypertensive patients (maximum effective RR values were 1.144 and 1.122, respectively). Extremely high levels of relative humidity (RH) (95th percentile, 94.29%) reduced the risk of death (RR value was 0.893). The stratified results showed that the elderly and female populations are more susceptible to low DTR levels, whereas extremely high levels of RH have a more significant protective effect on both populations.

CONCLUSION

Overall, we found that exposure to low DTR and high T mean environments increases the risk of death for hypertensive patients, while exposure to extremely high RH environments significantly reduces the risk of death for hypertensive patients. These findings contribute valuable insights for shaping targeted prevention and control strategies.

Association of greenspaces exposure with cardiometabolic risk factors: a systematic review and meta-analysis

BACKGROUND

Cardiometabolic conditions are major contributors to the global burden of disease. An emerging body of evidence has associated access to and surrounding public open spaces (POS) and greenspace with cardiometabolic risk factors, including obesity, body mass index (BMI), hypertension (HTN), blood glucose (BG), and lipid profiles. This systematic review aimed to synthesize this evidence.

METHODS

This systematic review was conducted based on the PRISMA guidelines. Four electronic databases including Web of Science, PubMed, Scopus, and Google Scholar were searched for eligible articles published until July 2023. All observational studies which assessed the association of greenspace and POS with cardiometabolic risk factors including obesity, BMI, HTN, BG, and lipid profiles were included and reviewed by two authors independently. Heterogeneity between studies was assessed using the I2 index and Cochrane's Q test. Random/fixed effect meta-analyses were used to combine the association between greenspace exposure with cardiometabolic risk factors.

RESULTS

Overall, 118 relevant articles were included in our review. The majority of the articles were conducted in North America or Europe. In qualitative synthesis, access or proximity to greenspaces or POS impacts BMI and blood pressure or HTN, BG, and lipid profiles via various mechanisms. According to the random effect meta-analysis, more access to greenspace was significantly associated with lower odds of HTN (odds ratio (OR): 0.81, 95% confidence intervals (CIs): 0.61-0.99), obesity (OR: 0.83, 95% CIs: 0.77-0.90), and diabetes (OR:0.79, 95% CI: 0.67,0.90).

CONCLUSIONS

Findings of this systematic review and meta-analysis suggested that greenspace accessibility is associated with some cardiometabolic risk factors. Improving greenspace accessibility could be considered as one of the main strategies to reduce cardiometabolic risk factors at population level.

Urban greenspaces and child blood pressure in China: Evidence from a large population-based cohort study

BACKGROUND

With the world's population steadily shifting toward urban living, children's engagement with the natural environment seems to be diminishing. This raises significant concerns about the influence of urban greenspaces on the cardiovascular health of children.

OBJECTIVE

To assess the association between urban greenspaces exposure and blood pressure (BP) in Chinese primary schoolchildren.

METHODS

This prospective cohort study used data from the Children's growth environment, lifestyle, physical, and mental health development (COHERENCE) project in Guangzhou, China. Participants included 164,853 primary schoolchildren starting from 2016/17 to 2019/20 academic year. We assessed the surrounding greenspaces at home and school by using Sentinel-2 satellite data on the normalized difference vegetation index. Prehypertension and hypertension status were defined with BP above 90th to less than the 95th percentile, at or above the 95th percentile, respectively. The association of surrounding greenness with children's BP levels and risk of prehypertension/hypertension were examined using linear mixed-effects models and Cox proportional hazards model.

RESULTS

Among 164,853 eligible children aged 7.21 (0.74) years, 89,190 (54.1%) were boys. Our results showed that average systolic and diastolic BP increased by 0.48 and 0.42 standard deviations, respectively, over the 3-year follow-up. We identified 23,225 new cases of prehypertension and 35,067 of hypertension status. An interquartile range increase both in home-, school- and home-school NDVI100m was significantly associated with a reduction of 0.018-0.037 in BP z-scores and a 2.7%-7.6% lower risk of hypertension. Additionally, family socioeconomic status modified the impact of home-school greenness on BP levels. Air pollution exhibited mediating effects solely in school-greenness-BP associations, while physical activity and children's BMI mainly mediated the relationships between home-greenness and BP.

CONCLUSION

The findings of this large cohort study suggest that surrounding greenspaces are associated with lower BP levels and a decreased risk of prehypertension and hypertension in Chinese schoolchildren.

Exposure to Neighborhood Greenness and Hypertension Incidence in Adults: A Longitudinal Cohort Study in Taiwan

BACKGROUND

There are few studies on the health effects of long-term exposure to neighborhood greenness in a longitudinal setting, especially in Asian countries with high population densities.

OBJECTIVES

This study investigates the association between long-term exposure to neighborhood greenness and hypertension among adults in Taiwan.

METHODS

We selected 125,537 participants (≥ 18  years of age) without hypertension from Taiwan who had joined the standard medical examination program between 2001 and 2016. Neighborhood greenness was estimated using the normalized difference vegetation index (NDVI), derived from satellite images at a resolution of 250   m 2 . The 2-y average NDVI value within a 500 -m circular buffer around participants' residences was calculated. A time-varying Cox regression model was used to investigate the association between neighborhood greenness and incident hypertension. Mediation analyses were performed to examine whether the association was explained by air pollution, leisure-time physical exercise, or body mass index (BMI).

RESULTS

Compared with living in areas within the first quartile of neighborhood greenness, living in areas within the second, third, and fourth quartiles of neighborhood greenness was found to be associated with a lower risk of hypertension, with hazard ratios (HRs) and 95% confidence intervals (CIs) of 0.95 (95% CI: 0.91, 1.00), 0.95 (95% CI: 0.90, 0.99), and 0.93 (95% CI: 0.88, 0.97), respectively. Each 0.1-unit increase in the NDVI was associated with a 24% lower risk of developing hypertension (HR = 0.76; 95% CI: 0.66, 0.87), with this associations being stronger among males and those with higher education levels. This association was slightly mediated by BMI but not by air pollution or leisure-time physical exercise.

DISCUSSION

Our findings suggest the protective effects of neighborhood greenness on hypertension development, especially in males and well-educated individuals. Our results reinforced the importance of neighborhood greenness for supporting health. https://doi.org/10.1289/EHP13071.

Lower regional urbanicity and socioeconomic status attenuate associations of green spaces with hypertension and diabetes mellitus: a national representative cross-sectional study in China

BACKGROUND

High blood pressure (HBP) and diabetes mellitus (DM) are two of the most prevalent cardiometabolic disorders globally, especially among individuals with lower socio-economic status (SES). Studies have linked residential greenness to decreased risks of HBP and DM. However, there has been limited evidence on whether SES may modify the associations of residential greenness with HBP and DM.

METHODS

Based on a national representative cross-sectional study among 44,876 adults, we generated the normalized difference vegetation index (NDVI) at 1 km spatial resolution to characterize individuals' residential greenness level. Administrative classification (urban/rural), nighttime light index (NLI), individual income, and educational levels were used to characterize regional urbanicity and individual SES levels.

RESULTS

We observed weaker inverse associations of NDVI with HBP and DM in rural regions compared to urban regions. For instance, along with per interquartile range (IQR, 0.26) increment in residential NDVI at 0∼5 year moving averages, the ORs of HBP were 1.04 (95%CI: 0.94, 1.15) in rural regions and 0.85 (95%CI: 0.79, 0.93) in urban regions (P = 0.003). Along with the decrease in NLI levels, there were continuously decreasing inverse associations of NDVI with DM prevalence (P for interaction <0.001). In addition, weaker inverse associations of residential NDVI with HBP and DM prevalence were found among individuals with lower income and lower education levels compared to their counterparts.

CONCLUSIONS

Lower regional urbanicity and individual SES could attenuate the associations of residential greenness with odds of HBP and DM prevalence.

Associations of Urban Built Environment with Cardiovascular Risks and Mortality: a Systematic Review

With rapid urbanization, built environment has emerged as a set of modifiable factors of cardiovascular disease (CVD) risks. We conducted a systematic review to synthesize evidence on the associations of attributes of urban built environment (e.g. residential density, land use mix, greenness and walkability) with cardiovascular risk factors (e.g. hypertension and arterial stiffness) and major CVD events including mortality. A total of 63 studies, including 31 of cross-sectional design and 32 of longitudinal design conducted across 21 geographical locations and published between 2012 and 2023 were extracted for review. Overall, we report moderately consistent evidence of protective associations of greenness with cardiovascular risks and major CVD events (cross-sectional studies: 12 of 15 on hypertension/blood pressure (BP) and 2 of 3 on arterial stiffness; and longitudinal studies: 6 of 8 on hypertension/BP, 7 of 8 on CVD mortality, 3 of 3 on ischemic heart disease mortality and 5 of 8 studies on stroke hospitalization or mortality reporting significant inverse associations). Consistently, walkability was associated with lower risks of hypertension, arterial stiffness and major CVD events (cross-sectional studies: 11 of 12 on hypertension/BP and 1 of 1 on arterial stiffness; and longitudinal studies: 3 of 6 on hypertension/BP and 1 of 2 studies on CVD events being protective). Sixty-seven percent of the studies were rated as "probably high" risk of confounding bias because of inability to adjust for underlying comorbidities/family history of diseases in their statistical models. Forty-six percent and 14% of the studies were rated as "probably high" risk of bias for exposure and outcome measurements, respectively. Future studies with robust design will further help elucidate the linkages between urban built environment and cardiovascular health, thereby informing planning policies for creating healthy cities.

Long-term effects of PM2.5 components on hypertension: A national analysis in China

BACKGROUND

Evidence is less about the associations between fine particulate matter (PM_2.5) components and hypertension. We aimed to examine the long-term effects of PM_2.5 components on prevalence of hypertension, diastolic blood pressure (DBP) and systolic blood pressure (SBP).

METHODS

We included participants between March 1, and July 31, 2021, from 13 provinces in China. Geocoded residential address was used for exposure assignment. Mixed-effect regression was used to assess 3-year average concentrations of PM_2.5 and its components (black carbon, organic matter, nitrate, ammonium, and sulfate) on prevalence of hypertension, DBP and SBP with covariate-adjusted. SHapley Additive exPlanation was used to compare the contribution of PM_2.5 components to hypertension, DBP, and SBP. Sex and age subgroup were also analyzed.

RESULTS

We enrolled a total of 113,159 participants aged ≥18 years. Long-term exposure to PM_2.5 and its components (black carbon, organic matter, nitrate, ammonium, and sulfate) had associations with prevalence of hypertension, with the Odds Ratios and 95% confidence interval (CI) of 1.06 (95%CI: 1.03-1.09), 1.07 (95%CI: 1.04-1.09), 1.07 (95%CI: 1.04-1.10), 1.05 (95%CI: 1.01-1.08), 1.03 (95%CI: 1.00-1.06), and 1.03 (95%CI: 1.00-1.04), respectively. Effects of that except for black carbon on DBP with per interquartile upticks of concentration were 0.23 (95%CI: 0.11-0.35), 0.17 (95%CI: 0.04-0.29), 0.35 (95%CI: 0.21-0.48), 0.40 (95%CI: 0.28-0.52), and 0.25 (95%CI: 0.13-0.26), respectively. Ammonium was associated with SBP, corresponding to an increase of 0.18 (95%CI: 0.01-0.35). Males had higher risks of DBP (Z = 2.54-6.08, P < 0.001). Older people were substantially more affected by PM_2.5 and its components. Nitrate showed the highest contribution to hypertension, DBP and SBP compared with other components.

CONCLUSIONS

Long-term exposure to PM_2.5 and its components had adverse consequences on prevalence of hypertension, DBP and SBP, especially for males and older people. Nitrate contributed the highest to hypertension, DBP and SBP. Findings may have implications for pollution and hypertension control.

Does the quality of street greenspace matter? Examining the associations between multiple greenspace exposures and chronic health conditions of urban residents in a rapidly urbanising Chinese city

BACKGROUND

Numerous studies have demonstrated that greenspace(GS) exposure is associated with health improvements in individuals with hypertension and diabetes. However, studies examining the associations between multiple GS exposures and chronic health conditions in developing countries are limited.

METHODS

Geospatial data and spatial analysis were employed to objectively measure the total neighbourhood vegetative cover (mean value of normalised difference vegetation index [NDVI] within specific buffer zone) and proximity to park-based GS (network distance from home to the entrance of park-based GS). Street view imagery and machine learning techniques were used to measure the subjective perceptions of street GS quality. A multiple linear regression model was applied to examine the associations between multiple GS exposures and the prevalence of hypertension and diabetes in neighbourhoods located in Qingdao, China.

RESULTS

The model explained 29.8% and 28.2% of the prevalence of hypertension and diabetes, respectively. The results suggested that: 1) the total vegetative cover of the neighbourhood was inversely correlated with the prevalence of hypertension (β = -0.272, p = 0.013, 95% confidence interval (CI): [-1.332, -0.162]) and diabetes (β = -0.230, p = 0.037, 95% CI: [-0.720, -0.008]). 2) The street GS quality was negatively correlated with the prevalence of hypertension (β = -0.303, p = 0.007, 95% CI: [-2.981, -0.491]) and diabetes (β = -0.309, p = 0.006, 95% CI: [-1.839, -0.314]). 3) Proximity to park-based GS and the prevalence of hypertension and diabetes mellitus were not significantly correlated.

CONCLUSIONS

This study used subjective and objective methods to comprehensively assess the greenspace exposure from overhead to eye level, from quantity, proximity to quality. The results demonstrated the beneficial relationships between street GS quality, total vegetative cover, and chronic health in a rapidly urbanising Chinese city. Furthermore. the effect of street GS quality was more pronounced in potentially mitigating chronic health problems, and improving the quality of street GS might be an efficient and effective intervention pathway for addressing chronic health issues in densely populated cities.

Cross-sectional associations of different types of nature exposure with psychotropic, antihypertensive and asthma medication

BACKGROUND

Exposure to natural environments is thought to be beneficial for human health, but the evidence is inconsistent.

OBJECTIVE

To examine whether exposure to green and blue spaces in urban environments is associated with mental and physical health in Finland.

METHODS

The Helsinki Capital Region Environmental Health Survey was conducted in 2015-2016 in Helsinki, Espoo and Vantaa in Finland (n=7321). Cross-sectional associations of the amounts of residential green and blue spaces within 1 km radius around the respondent's home (based on the Urban Atlas 2012), green and blue views from home and green space visits with self-reported use of psychotropic (anxiolytics, hypnotics and antidepressants), antihypertensive and asthma medication were examined using logistic regression models. Indicators of health behaviour, traffic-related outdoor air pollution and noise and socioeconomic status (SES) were used as covariates, the last of these also as a potential effect modifier.

RESULTS

Amounts of residential green and blue spaces or green and blue views from home were not associated with medications. However, the frequency of green space visits was associated with lower odds of using psychotropic medication (OR=0.67, 95% CI 0.55 to 0.82 for 3-4 times/week; 0.78, 0.63 to 0.96 for ≥5 times/week) and antihypertensive (0.64, 0.52 to 0.78; 0.59, 0.48 to 0.74, respectively) and asthma (0.74, 0.58 to 0.94; 0.76, 0.59 to 0.99, respectively) medication use. The observed associations were attenuated by body mass index, but no consistent interactions with SES indicators were observed.

CONCLUSIONS

Frequent green space visits, but not the amounts of residential green or blue spaces, or green and blue views from home, were associated with less frequent use of psychotropic, antihypertensive and asthma medication in urban environments.

Relationship between Built-Up Environment, Air Pollution, Activity Frequency and Prevalence of Hypertension-An Empirical Analysis from the Main City of Lanzhou

In the process of promoting the strategy of a healthy China, the built environment, as a carrier of human activities, can effectively influence the health level of residents in the light of its functional types. Based on the POI data of four main urban areas in Lanzhou, this paper classifies the built environment in terms of function into four types. The association between different types of built environments and the prevalence of hypertension was investigated by using the community as the study scale, and activity frequency, air pollution and green space were used as mediating variables to investigate whether they could mediate the relationship between built environments and hypertension. The results indicate that communities with a high concentration of commercial service facilities, road and traffic facilities and industrial facilities have a relatively high prevalence of hypertension. By determining the direct, indirect and overall effects of different functional types of built environment on the prevalence of hypertension, it was learned that the construction of public management and service facilities can effectively mitigate the negative effects of hypertension in the surrounding residents. The results of the study contribute to the rational planning of the structure of the built environment, which is beneficial for optimizing the urban structure and preventing and controlling chronic diseases such as hypertension.

The Differences by Sex and Gender in the Relationship Between Urban Greenness and Cardiometabolic Health: A Systematic Review

In an increasingly urbanized world, where cardiometabolic issues in cities have raised public health concerns, urban greenness is known to be beneficial for some of the most common health issues. However, the examination of the contribution of sex and gender regarding the benefits of urban greenness for people's cardiometabolic health is lacking. For that reason, we conducted a systematic review of previous literature on the topic following the PRISMA methodology. Additionally, we assessed the quality of the included articles, which we found satisfactory as most papers were of very good or good quality. We explored the relationship between urban greenness exposure and cardiovascular risk factors, cardiovascular diseases, and mortality from cardiovascular diseases. Results suggest that urban greenness is protective against cardiovascular risk factors, diseases, and mortality. When stratifying results by sex and gender, findings point to urban greenness being more beneficial for women and females in stroke and cardiovascular risk factors, except for hypertension and lipid accumulation product. On the other hand, males were more protected by urban greenness in terms of cardiovascular diseases and CVD-related mortality, thus proving that sex and gender health inequalities exist. Furthermore, looking towards the future, research needs to use the proper terminology for sex and gender and policy makers should design urban greenness with a gender perspective.

The evaluation of the 3-30-300 green space rule and mental health

BACKGROUND AND AIMS

Urban green space has many health benefits, but it is still unclear how much actually is needed for better health. Recently a new 3-30-300 rule of thumb for urban forestry and urban greening has been proposed, but this rule has not been evaluated for benefits on health. The rule requires that every citizen should be able to see at least three trees from their home, have 30 percent tree canopy cover in their neighbourhood and not live more than 300 m away from the nearest park or green space. The aim of this study was to evaluate the relationship between the 3-30-300 green space rule and its components in relation to mental health.

METHODS

We conducted a cross-sectional study based on a population-based sample of 3145 individuals aged 15-97 years from in Barcelona, Spain who participated in the Barcelona Health Survey (2016-2017). We created 3-30-300 green space indicators using questionnaire data, GIS, remote sensing and land cover maps. Mental health status was assessed with the 12-item General Health Questionnaire (GHQ-12) and also the use of tranquilizer/sedatives or antidepressants and psychiatrist or psychologist visits. Analyses were conducted using mixed effects logistic regression models with districts as the random effect, adjusted for relevant covariates.

RESULTS

We found that people in Barcelona had relatively little exposure to green space, whether through window view, living in an area with sufficient greenness, or access to a major green space, and only 4.7% met a surrogate 3-30-300 green space rule. Residential surrounding greenness, but not tree window view or access to major green space, was significantly associated with better mental health, less medication use, and fewer psychologist or psychiatrist visits. Meeting the full surrogate 3-30-300 green space rule was associated with better mental health, less medication use, and fewer psychologist or psychiatrist visits, but only for the latter combined the association was statistically significant (Odds ratio = 0.31, 95% CI: 0.11, 0.91).

CONCLUSION

Few people achieved the 3-30-300 green space in Barcelona and we used a surrogate measure. We observed health benefits when the full surrogate rule was met.

Association between smoking and hypertension under different PM2.5 and green space exposure: A nationwide cross-sectional study

Background

Smoking has been widely reported to have a significant relationship with hypertension, but the past description of this relationship has not been uniform. In addition, there has been a lack of research to discuss the impact of environmental exposure on the relationship between smoking and hypertension. Therefore, this study estimates the association between smoking and hypertension in middle aged and elderly people in China under different PM_2.5 (fine particulate matter) concentrations and the green space exposure conditions.

Methods

Individual sample data from the China Health and Retirement Longitudinal Study in 2018 and the long-term average exposure concentration of fine particles and green space exposure for all participants were used with a multilevel binary logistic mixed effects model. Adjustments were made for sociodemographic characteristics and other health behaviors including drinking, physical activity, and social activity. The normalized difference vegetation index (NDVI) and PM_2.5 concentration stratification were assigned with the median of the population exposure concentration as the dividing line, and the dual environmental factor stratification was assigned in combination with the two types of environmental exposure. The analysis was also stratified using age groups.

Results

A total of 10,600 participants over the age of 45 were included in the study. The effects of smoking on hypertension were diverse under different environmental exposure conditions. There was a significant relationship between smoking behavior and hypertension in the Low-NDVI group, and the effect value of this relationship was significantly different from that in the High-NDVI group. Furthermore, for respondents exposed to low green spaces and high PM_2.5 environments at the same time (Low-NDVI/High-PM_2.5 group), their smoking behavior may lead to an increase in the risk of hypertension. In addition, the risk of hypertension caused by smoking in the middle-aged (45-64) was significant under low green space exposure, but the effect difference between the different age groups was not significant.

Conclusions

The relationship between smoking and hypertension was different under different environmental exposure conditions. Exposure to low green spaces may strengthen the association between smoking and hypertension risk. When participants were exposed to both low green spaces and high PM_2.5 concentrations, the risk of hypertension caused by smoking was significantly higher than that of those who were exposed to high green spaces and low PM_2.5 concentrations.

The neighbourhood environment and profiles of the metabolic syndrome

BACKGROUND

There is a dearth of studies on how neighbourhood environmental attributes relate to the metabolic syndrome (MetS) and profiles of MetS components. We examined the associations of interrelated aspects of the neighbourhood environment, including air pollution, with MetS status and profiles of MetS components.

METHODS

We used socio-demographic and MetS-related data from 3681 urban adults who participated in the 3rd wave of the Australian Diabetes, Obesity and Lifestyle Study. Neighbourhood environmental attributes included area socio-economic status (SES), population density, street intersection density, non-commercial land use mix, percentages of commercial land, parkland and blue space. Annual average concentrations of NO₂ and PM_2.5 were estimated using satellite-based land-use regression models. Latent class analysis (LCA) identified homogenous groups (latent classes) of participants based on MetS components data. Participants were then classified into five metabolic profiles according to their MetS-components latent class and MetS status. Generalised additive mixed models were used to estimate relationships of environmental attributes with MetS status and metabolic profiles.

RESULTS

LCA yielded three latent classes, one including only participants without MetS ("Lower probability of MetS components" profile). The other two classes/profiles, consisting of participants with and without MetS, were "Medium-to-high probability of high fasting blood glucose, waist circumference and blood pressure" and "Higher probability of MetS components". Area SES was the only significant predictor of MetS status: participants from high SES areas were less likely to have MetS. Area SES, percentage of commercial land and NO₂ were associated with the odds of membership to healthier metabolic profiles without MetS, while annual average concentration of PM_2.5 was associated with unhealthier metabolic profiles with MetS.

CONCLUSIONS

This study supports the utility of operationalising MetS as a combination of latent classes of MetS components and MetS status in studies of environmental correlates. Higher socio-economic advantage, good access to commercial services and low air pollution levels appear to independently contribute to different facets of metabolic health. Future research needs to consider conducting longitudinal studies using fine-grained environmental measures that more accurately characterise the neighbourhood environment in relation to behaviours or other mechanisms related to MetS and its components.

Weekly green space visit duration is positively associated with favorable health outcomes in people with hypertension: Evidence from Shenzhen, China

BACKGROUND

Studies from high income 'western' countries indicate that green space visit duration is associated with better health. However, scant comparable research has been done in developing countries with rapid urbanization and on the potential health impacts of specific green infrastructure.

OBJECTIVE

Associations between green space visit duration, green infrastructure and various health outcomes were assessed in hypertensive patients.

METHODS

A stratified multi-stage cluster random sampling method was applied to select 1116 patients with hypertension aged 35 years or older in Shenzhen, China. Face-to-face survey, physical examination and laboratory biochemical tests were applied to obtain information. Binary logistic regressions with restricted cubic splines were used to explore the degree of linearity in associations between green space visit duration and the following health outcomes: central obesity; diabetes; blood pressure; dyslipidemia; poor physical health; poor mental health. Models were adjusted for age, sex, education, marital status, occupation, and socioeconomic status. Further analysis was made for presence of the following health promoting green infrastructure: health knowledge promotion areas; walking trails; fitness areas; group exercise venues.

RESULTS

Each additional 30 min green space visitation was linearly associated with lower odds of self-reported poor mental health [OR (95%CI): 0.937 (0.891-0.985)], self-reported poor physical health [OR (95%CI): 0.918 (0.872-0.966)], and central obesity [OR (95%CI): 0.951 (0.907-0.997)]. Odds of poor mental health [OR (95%CI): 0.886 (0.788-0.997)], poor physical health [OR (95%CI): 0.882 (0.782-0.996)] and central obesity [OR (95%CI): 0.855 (0.765-0.955)] were founded to decrease with a greater number of health promoting green infrastructure.

CONCLUSION

More time spent in green space and with more types of green infrastructure were favourably associated with central obesity, and physical and mental health in people with hypertension.

Green areas and students' academic performance in the Federal District, Brazil: An assessment of three greenness metrics

Most of the epidemiological investigations looking at the health benefits of green spaces have measured the level of green areas by using only one approach, mainly the Normalized Difference Index - NDVI (a satellite-derived indicator). We hypothesized a difference in the association between health and green space depending on the metric used to measure green exposure. This study considers students' academic performance as a proxy of cognitive abilities (a health indicator). We estimated the relationship between green areas and students' academic performance in the Federal District (FD), Brazil, with three different greenness metrics: NDVI, distance to green spaces (m) - obtained from land use data, and quantity of green spaces (m²) - also from land use data. We assessed student-level academic performance data provided by the Department of the Education in the FD. The data includes students from the public schools in the FD for 256 schools (all the public schools in the FD) and 344,175 students (all the students enrolled in the public schools in the FD in 2017-2020).). For the first metric represented by the distance to green spaces, we estimated the straight-line distance between each school and the nearest green area. For NDVI and quantity of green spaces, we estimated the area of all green spaces within buffers of 500 m, 750 m, and 1 km around the schools. We applied a cross-sectional study design using mixed-effects regression models to analyze the association exposure to green areas around schools and student-level academic performance. Our results confirmed our hypothesis showing that the impact of green areas on students' performance varied significantly depending on the type of green metric. After adjustments for the covariates, we estimated that NDVI is positively associated with school-level academic performance, with an estimated coefficient of 0.91 (95%CI: 0.83; 0.99) for NDVI values at a school's centroid. Distance to green areas was negatively associated with academic performance [-2.09 × 10^-5 (95CI: 3.91 × 10^-5; -2.84 × 10^-6]. The quantity of green areas was estimated with mixed results (direction of the association), depending on the buffer size. Results from this paper suggest that epidemiological investigations must consider the different effects of greenness measures when looking at the association between green space and academic performance. More studies on residual confounding from this association with a different study design are needed to promote public health by making schools healthier.

The effects of greenness exposure on hypertension incidence among Chinese oldest-old: a prospective cohort study

BACKGROUND

Although the oldest-old (those aged over 80 years) are vulnerable to environmental factors and have the highest prevalence of hypertension, studies focusing on greenness exposure and the development of hypertension among them are insufficient. The aim of this study was to explore the association between residential greenness and hypertension in the oldest-old population.

METHODS

This cohort study included data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). The oldest-old were free of hypertension at baseline (2008), and hypertension events were assessed by follow-up surveys in 2011, 2014, and 2018. The one-year averages of the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) at 500-m buffer before the interview year of incident hypertension or last censoring interview were collected at the level of 652 residential units (district or county). The linear or nonlinear association between greenness and hypertension incidence was analyzed using the Cox proportional hazards model with penalized splines. The linear links between greenness and hypertension incidence were determined using the Cox proportional hazards model included a random effect term.

RESULTS

Among 5253 participants, the incidence rate of hypertension was 7.25 (95% confidence interval [CI]: 6.83-7.67) per 100 person-years. We found a nonlinear association between greenness exposure and hypertension risk, and the exposure-response curve showed that 1 change point existed. We examined the linear effect of greenness on hypertension by categorizing the NDVI/EVI into low and high-level exposure areas according to the change point. We found more notable protective effects of each 0.1-unit increase in greenness on hypertension incidence for participants living in the high-level greenness areas (hazard ratio (HR) = 0.60; 95% CI: 0.53-0.70 for NDVI; HR = 0.46; 95% CI: 0.37-0.57 for EVI). In contrast, no significant influence of greenness exposure on hypertension risk was found for participants living in the low-level greenness areas (HR = 0.77; 95% CI: 0.38-1.55 for NDVI; HR = 0.73; 95% CI: 0.33-1.63 for EVI).

CONCLUSIONS

Greenness exposure is nonlinearly associated with hypertension risk among the oldest-old, presenting its relationship in an inverse "U-shaped" curve. Greenness is a protective factor that decreases the risk of hypertension.

Association between greenspace and blood pressure: A systematic review and meta-analysis

Many studies have investigated the association between greenspaces and blood pressure (BP), but the results remain mixed. We conducted a systematic review and meta-analysis to comprehensively evaluate the evidence concerning greenspaces with BP levels and prevalent hypertension. Systematic literature searches were performed in Web of Science, PubMed, and Embase up to 25 April 2021. Combined effect estimates were calculated using random-effect models for each greenspace exposure assessment method that had been examined in ≥3 studies. Sensitivity analysis, subgroup analysis, and publication bias were also conducted. Of 38 articles (including 52 analyses, 5.2 million participants in total) examining the effects of normalized difference vegetation index (NDVI) (n = 23), proportion of greenspace (n = 11), distance to greenspace (n = 9), and others (n = 9) were identified. Most studies (65%) reported beneficial associations between greenspaces and BP levels/hypertension. Our results of meta-analyses showed that higher NDVI_500m was significantly associated with lower levels of systolic blood pressure (SBP = -0.77 mmHg, 95%CI: -1.23 to -0.32) and diastolic blood pressure (DBP = -0.32 mmHg, 95%CI: -0.57 to -0.07). We also found that NDVI in different buffers and the proportion of greenspaces were significantly associated with lower odds (1-9%) of hypertension. However, no significant effect was found for distance to greenspaces. In summary, our results indicate the beneficial effects of greenspace exposure on BP and hypertension. However, future better-designed studies, preferably longitudinal, are needed to confirm and better quantify the observed benefits in BP and/or hypertension.

Residential area greenness and hypertension: a national assessment on urban adults in Bangladesh

This study investigated the associations between greenness and blood pressure (BP) metrics (systolic BP [SBP], diastolic BP [DBP], hypertension) among urban adults in Bangladesh and the potential mediation effects of body mass index (BMI) using 2011 Bangladesh Demographic and Health Survey data for 2360 urban adults (aged ≥35 years). The Enhanced Vegetation Index was used as a measure of residential area greenness. Associations between greenness and BP metrics were estimated using linear and binary logistic regression models. We also conducted mediation analyses. Greater area-level greenness was inversely associated with SBP (β -1.33, 95%CI: -2.46, -.20), DBP (β -.83, 95%CI: -1.64, -.02), and hypertension (adjusted odds ratio .87, 95%CI: .77, .98). BMI substantially mediated associations between greenness and BP metrics. Adopting urban greening policies could reduce the risk of hypertension, thus can contribute to reduction of non-communicable disease burden in Bangladesh. Longitudinal studies are required to further investigate the causal pathways.

Associations of combined exposures to ambient temperature, air pollution, and green space with hypertension in rural areas of Anhui Province, China: A cross-sectional study

Hypertension (HTN) was a major preventable cause of cardiovascular disease (CVD), contributing to a huge disease burden. Ambient temperature, air pollution and green space were important influencing factors of HTN, and few studies have assessed the effects and interactions of ambient temperature, air pollution and green space on HTN in rural areas. In this study, we selected 8400 individuals randomly in rural areas of Anhui Province by a multi-stage stratified cluster sampling. A total of 8383 individuals were included in the final analysis. We collected particulate pollutants and meteorological data from the local air quality monitoring stations and National Center for Meteorological Science from January 1 to December 31, 2020, respectively. The normalized differential vegetation index (NDVI) of Anhui Province in 2020 was produced and processed by remote sensing inversion on the basis of medium resolution satellite images. The average annual mean exposure concentrations of air pollution, meteorological factors, and NDVI were calculated for each individual based on the geocoded residential address. HTN was defined according the Chinese Guidelines for Prevention and Treatment of HTN. The effects and interactions of ambient temperature, air pollution and green space on HTN were evaluated by generalized linear model and interaction model, respectively. In this study, the prevalence of HTN was 24.14%. The adjusted odd ratio of HTN for each 1 μg/m³ increasing in PM_2.5 and PM₁₀, 1 °C of ambient temperature, and 0.1 of NDVI were:1.276 (1.013, 1.043), 1.012 (1.006, 1.018), 0.862 (0.862, 0.981) and 0.669 (0.611, 0.733), respectively. The results showed that air pollutants were positively correlated with HTN, while ambient temperature and green space were negatively correlated with HTN. Meanwhile, the negative associations of green space on HTN could decrease with the increasing concentrations of air pollution, but increase with the rising of ambient temperature.

Associations of greenness surrounding schools with blood pressure and hypertension: A nationwide cross-sectional study of 61,229 children and adolescents in China

BACKGROUND

Greenness exposure may lower blood pressure. However, few studies of this relationship have been conducted with children and adolescents, especially in low and middle-income countries.

OBJECTIVES

To evaluate associations between greenness around schools and blood pressure among children and adolescents across China.

METHODS

We recruited 61,229 Chinese citizens aged 6-18 years from 94 schools in a nationwide cross-sectional study in seven Chinese provinces/province-level municipalities. Participants' blood pressures and hypertension were assessed with standardized protocols. Greenness levels within 500 m and 1,000 m of each school were estimated with three satellite-based indices: vegetation continuous fields (VCF), normalized difference vegetation index (NDVI), and soil adjusted vegetation index (SAVI). Generalized linear mixed models were used to evaluate associations between greenness and blood pressure, greenness and prevalent hypertension, using coefficient and odds ratio respectively. Stratified analyses and mediation analyses were also performed.

RESULTS

One interquartile range increase in greenness was associated with a 17%-20% reduced prevalence of hypertension for all measures of greenness (odds ratios for VCF_500m = 20% (95% CI:18%, 23%); for NDVI_500m = 17% (95% CI:13%, 21%); and for SAVI_500m = 17% (95% CI: 13%, 20%). Increases in greenness were also associated with reductions in systolic blood pressure (0.48-0.58 mmHg) and diastolic blood pressure (0.26-0.52 mmHg). Older participants, boys, and urban dwellers showed stronger associations than their counterparts. No evidence of mediation was observed for air pollution (i.e., NO₂ and PM_2.5) and body mass index.

CONCLUSION

Higher greenness around schools may lower blood pressure levels and prevalent hypertension among Chinese children and adolescents, particularly in older subjects, boys, and those living in urban districts. Further studies, preferably longitudinal, are needed to examine causality.

Natural and built environments and blood pressure of Alpine schoolchildren

BACKGROUND

Early life environments may influence children's blood pressure (BP), but evidence on the combined effects of natural and built environment exposures is scarce. The present study investigates the associations of natural and built environment indicators, traffic noise, and air pollution with BP in children living in Alpine valleys.

METHODS

In 2004/2005, 1251 school children (8-12 years old) were sampled for a cross-sectional survey in several Austrian and Italian mountain valleys. Children's mothers completed a questionnaire. The outcomes of interest were systolic and diastolic BP measured with a calibrated oscillometric device. Indicators of land cover assigned to the residential and school coordinates within 100 and 1000 m included normalized difference vegetation index (NDVI), tree canopy cover, and a broader naturalness indicator titled distance to nature (D2N). The presence of a home garden was also measured via self-report. Imperviousness density served as a proxy for the built environment. Residential air pollution (NO₂) and noise (L_den) from traffic were calculated using bespoke modeling. NO₂, L_den, physical activity, and body mass index (BMI) were treated as mediating pathways.

RESULTS

Higher NDVI and tree cover levels in residential and school surroundings and home gardens were consistently associated with lower BP. The built environment was associated with higher BP. Counterintuitive inverse associations between NO₂ and L_den and BP were also found. Structural equation modeling showed that higher levels of greenspace and presence of a home garden were weakly associated with more outdoor play spaces, and in turn with lower BMI, and ultimately with lower BP.

CONCLUSIONS

Exposure to natural environments may help maintain normal BP in children, while built environment may increase children's BP. Outdoor play and less adiposity in greener areas may mediate some of these associations. Evidence on air pollution and noise remains controversial and difficult to explain.

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

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

Willingness to Pay for Urban and Suburban Green

Peri-urban and urban green are considered among the basic priorities of the local government’s regional policy agenda, in line with the principles of spatial planning. This agenda is promoted at both the national and European levels through a variety of technical and institutional measures. Green spaces in urban and suburban areas are directly linked to the quality of life of urban residents and their environment. In this context, the purpose of this study is to investigate and identify the characteristics and factors that influence the residents of a small Greek city in terms of the value they attach to urban and suburban green spaces. These factors are identified through the residents’ willingness to pay (WTP) using the contingent valuation method (CVM). In general, the analysis aims to document the value of environmental economic methods as a tool in the management of natural heritage. According to the research, income and knowledge of environmental issues (global and local) as well as the benefits of green spaces (urban and suburban) are the key factors that drive residents to place a higher value on them. Future work may explore whether or how the COVID-19 pandemic affected city residents’ willingness to pay for green spaces.

Outdoor artificial light at night: A forgotten factor in green space and health research

Exposure to green space has been associated with a range of human health benefits, largely in spatial epidemiological studies. Green space and artificial light at night are both associated with breast and prostate cancer, depressive symptoms, obesity, and sleep problems, and are both influenced by the built environment and urbanisation. We identified a negative correlation between green space diversity and outdoor artificial light at night for Australian major cities. Outdoor artificial light at night is therefore a potential, but overlooked, confounder in spatial epidemiological studies of green space exposure and human health, and should be incorporated into future models.

Greenness-air pollution-physical activity-hypertension association among middle-aged and older adults: Evidence from urban and rural China

BACKGROUND

Although some evidence suggests that residential greenness may prevent hypertension in urban areas, limited attention has been paid to urban-rural disparities in the association of greenness with hypertension in rapidly urbanizing developing countries.

OBJECTIVES

The current study investigated the association between the amount of neighbourhood greenness and hypertension among middle and older aged people in Chinese urban and rural areas. It further examined whether PM_2.5 (particulate matter ≤2.5 μm in aerodynamic diameter) concentrations, physical activity, and body mass index (BMI) mediated the association of greenness with hypertension.

METHODS

We used data from 11 486 adults aged 50 years or above within the first wave of the Study on Global Ageing and Adult Health in China during 2007-2010. Hypertension was assessed by criterion-based measures of blood pressure. Residential greenness was characterized by satellite-derived Normalized Difference Vegetation Index. We employed multilevel generalized structural equation models to estimate the association between neighbourhood greenness and hypertension in urban and rural areas. Serial mediation models have been performed to test potential pathways linking greenness to hypertension.

RESULTS

In rural areas, a greater amount of residential greenness was directly associated with a decrease in the odds of hypertension (odds ratio = 0.51, 95% confidence interval 0.29-0.89). No direct association was observed in urban areas (odds ratio = 1.33, 95% confidence interval 0.94-1.89). Serial mediation models showed that the association of greenness with hypertension was completely mediated by PM_2.5 concentrations in urban areas, while the association of greenness with hypertension was only partially mediated by PM_2.5 concentrations and serial PM_2.5 concentrations-physical activity path in rural areas. There was no evidence that physical activity, air pollution-BMI path, air pollution-physical activity-BMI path, and physical activity-BMI path mediated the association in both urban and rural areas.

CONCLUSIONS

Higher neighbourhood greenness was directly associated with a lower prevalence of hypertension among middle and older aged adults in rural China but not in urban areas. The association of greenness with hypertension was completely mediated by air pollution (without any mediation effect of physical activity and BMI) in urban areas. In contrast, the association was partly mediated by air pollution, physical activity, and other unobservables in rural areas. Further longitudinal studies are warranted to prove a cause-and-effect association, which may help policymakers and practitioners to conduce effective interventions to prevent and control the prevalence of hypertension and the attendant disease burden.