Natural environments and suicide mortality in the Netherlands: a cross-sectional, ecological study

Increased urban greenspace in childhood associated with lower inattention deficit among adolescents

PURPOSE

There is a growing interest in assessing the benefits of exposure to urban greenspace on mental health due to the increased urbanization of youth and concerns for their mental health. We investigated the prospective associations of residential greenspace in childhood and mental health in adolescence. Use of a well-characterized birth cohort permitted adjustment for a range of potential confounding factors including family and neighborhood characteristics in addition to prior mental health problems, and exploration of moderation effects by sex and family socioeconomic status.

METHODS

We analyzed longitudinal data collected from 742 urban-dwelling participants of the Quebec Longitudinal Study of Children Development. The Normalized Difference Vegetation Index (NDVI) within 250, 500, and 1000 m buffer zones surrounding the home residence was used to indicate childhood exposure to greenspace. Six self-reported mental health problems at 15/17 years were examined using the Mental Health and Social Inadaptation questionnaire: inattention, hyperactivity/impulsivity, conduct, depression, anxiety, and suicidal ideation.

RESULTS

Childhood urban greenspace was associated with lower inattention problems in both females and males. We observed a 0.14 reduced standard deviation (SD) (β = - 0.14, SE = 0.05, p < 0.01) in relation to an interquartile range (IQR) increase of NDVI (0.15) at the 250 m buffer zone, and similar results were found in 500 m and 1000 m buffer zones. These associations only slightly attenuated after adjustment for individual (sex, childhood mental health), family (family SES, maternal age at birth, parental mental health, family composition), and neighborhood (material and social deprivation) characteristics (β = - 0.13, SE = 0.06, p = 0.03). No association was found for other mental health problems, and no moderation associations of sex or family socioeconomic status were observed.

CONCLUSION

 These findings suggest that increasing residential greenspace in cities may be associated with modest benefits in attentional capacities in youth, necessitating further research to elucidate the underlying mechanisms.

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.

Greenspace exposure may increase life expectancy of elderly adults, especially for those with low socioeconomic status

With an increasing aging population in many cities worldwide, promoting and maintaining the health of elderly individuals has become a pressing public health issue. Although greenspaces may deliver many health outcomes for the elderly population, existing evidence remains inconsistent, partly due to discrepancies in the measure of greenspace and health outcomes. In addition, few studies examined the effect of greenspace exposure on life expectancy at the individual level. Thus, this study comprehensively investigated the association between greenspace exposure and life expectancy among elderly adults in Guangzhou, China, based on the individual-level mortality dataset. The data were analyzed at both the individual level and aggregate level, and two types of buffers (straight-line vs. street-network buffer) were used to define individual greenspace exposure. After controlling for the random effects and multiple types of covariates, we found that 1) elderly individuals with higher greenspace exposure were associated with an increased life expectancy; 2) elderly individuals with lower socioeconomic status benefit more from greenspace (i.e., equigenesis hypothesis); 3) different greenspace measurements lead to different results; 4) greenspace had the highest effects on life expectancy and equigenesis within the street-network buffer distances of 3000 m and 2500 m, respectively. This study underscores the potential health benefits of greenspace exposure on elderly individuals and the importance of provision and upkeep of greenspace, especially among socially disadvantaged groups.

Greenspace related to bipolar disorder in Taiwan: Quantitative benefits of saving DALY loss and increasing income

Scientific evidence reported that surrounding greenspace could promote better mental health. Considering bipolar disorder as the health outcome, this study aimed to investigate the association between greenspace and bipolar disorder in Taiwan and quantified the benefits of greenspace on bipolar disorder adjusted for the international greenspace availability standard. By examining datasets across 348 townships, two quantitative measures (i.e., disability-adjusted life year loss and income) were used to represent the benefits. The incidence rate of bipolar disorder was obtained from Taiwan's National Health Insurance Research Database. Normalized different vegetation index (NDVI) was measured as a proxy for the greenspace availability. A generalized additive mixed model coupled with a sensitivity test were applied to evaluate the statistical association. The prevented fraction for the population (PFP) was then applied to develop a scenario for quantifying benefit. The result showed a significant negative association between greenspace and bipolar disorder in Taiwan. Compared to low greenspace, areas with medium and high greenspace may reduce the bipolar risk by 21% (RR = 0.79; 95% CI = 0.76-0.83) and 51% (RR = 0.49; 95% CI = 0.45-0.53). Calculating benefits, we found that the development of a scenario by increasing greenspace adjusted for availability indicator in township categorized as low greenspace could save in DALY loss due to bipolar disorder up to10.97% and increase in income up to 11.04% from the current situation. Lastly, this was the first study in Asia-Pacific to apply a customized greenspace increment scenario to quantify the benefits to a particular health burden such as bipolar disorder.

Association between urban greenspace, tree canopy cover and intentional deaths: An exploratory geospatial analysis

Greenspaces can provide restorative experiences, offer opportunities for outdoor recreation, and reduce mental fatigue; all of which may improve community health and safety. Yet few studies have examined the neighborhood-level benefits of greenspace in reducing violent deaths. This study explored the association between three distinct greenspace metrics: public greenspace quantity, public greenspace accessibility, neighborhood tree canopy cover, and intentional deaths (i.e., homicides and suicides). Generalized linear models and spatial error models investigated the association between greenspace, tree canopy and intentional deaths in three geographically distinct cities in North Carolina. Results revealed that increased neighborhood greenspace accessibility and tree canopy cover were associated with reduced intentional deaths in all three urban areas. Neighborhood greenspace accessibility was the most protective factor across all study areas. The relationship between neighborhood greenspace accessibility and intentional deaths was more significant for non-firearm deaths as compared to firearm deaths, indicating that weapon type may be an important consideration for neighborhood greenspace interventions. Compared to predominantly White neighborhoods, predominantly Black neighborhoods had higher rates of homicide in Asheville and Durham and higher rates of suicide in Charlotte. Future policy and research should focus on improving equitable access to existing and future greenspaces, especially in primarily Black neighborhoods.

Spatial Analysis of Greenspace and Mental Health in North Carolina: Consideration of Rural and Urban Communities

Greenspace positively impacts mental health. Previous research has focused on the greenspace-mental health relationship in urban areas. Yet, little work has looked at rural areas despite rural communities reporting similar rates of poor mental health outcomes and higher rates of suicide mortality compared with urban areas. This ecological research study examined the following research questions: (1) Do public and/or private greenspaces affect the spatial distribution of mental health outcomes in North Carolina? (2) Does this relationship change with rurality? Emergency department data for 6 mental health conditions and suicide mortality data from 2009 to 2018 were included in this analysis. Spatial error and ordinary least squares regressions were used to examine the influence of public and private greenspace quantity on mental health in rural and urban communities. Results suggest greenspace benefits mental health in rural and urban communities. The strength of this relationship varies with urbanity and between public and private greenspaces, suggesting a more complex causal relationship. Given the high case counts and often lower density of mental health care facilities in rural areas, focusing attention on low-cost mental health interventions, such as greenspace, is important when considering rural mental health care.

The environment a young person grows up in is associated with their mental health: A nationwide geospatial study using the integrated data infrastructure, New Zealand

BACKGROUND

Mental health conditions often arise during adolescence, are multifaceted in aetiology, and may be related to the type of environment in which young people reside. This study used nationwide population-level data to investigate whether the environment a young person grows up in is associated with their mental health.

METHOD

Data were extracted from the Integrated Data Infrastructure (IDI), a large nationwide research repository, for 917,211 young people (aged 10-24 years) including sociodemographic and mental health data (i.e. emotional, behavioural, substance problems, and self-harm). Environmental data were sourced from the nationwide area-based Healthy Location Index (HLI), which has comprehensive data on the location of several health-constraining (i.e. fast-food outlets) and health-promoting features (i.e. physical activity facilities). Environments were classified as: i) health-promoting, ii) health-constraining, or iii) neither. Associations between the HLI and mental health were investigated using multi-level mixed effects logistic regression modelling.

RESULTS

Overall, there was evidence of an association between the environment a young person resided in and their mental health. Young people residing in health-constraining environments had higher odds of any mental health condition (Adjusted Odds Ratio (AOR) = 1.020 [1.001, 1.040]) and any emotional condition (AOR = 1.037 [1.012, 1.062]). Young people residing in health-promoting environments had lower odds of substance problems (AOR = 0.950 [0.905, 0.997]). There were no significant effects of the environment on behavioural conditions.

CONCLUSION

Our study utilises a large national sample of almost one million young people to confirm the importance of environmental determinants for mental health. It is possible that leverage points for improving the mental health of young people, and reducing the burden to the health system of mental health, can be sought in upstream environmental based interventions.

The association between nation-level social and economic indices and suicide rates: A pilot study

Ever since the pioneering work of Emile Durkheim, it has been known that regional or national suicide rates can be influenced by a variety of social and economic factors. Recent research has found a robust association between two country-level economic indices-gross national product and unemployment rate-and suicide rates, particularly in men. However, the association between other country-level social indices-such as measures of social integration, inequality, environmental preservation and political freedom-and suicide rates has not been studied at the cross-national level. In the current study, national suicide rates for men and women were examined in relation to seven indices measuring subjective wellbeing, sustainable development, type of political regime, economic and gender inequality, and social capital. It was found that the Happy Planet Index, a composite measure of subjective wellbeing and sustainable development, was negatively associated with suicide rates independent of gender, and even after adjusting for possible confounding factors. Economic inequality was associated with suicide in men, and social capital was associated with suicide in women. Moreover, the strength and direction of the associations observed between socioeconomic indices and suicide varied across income groups. These results highlight the need for a closer evaluation of the link between large-scale ("macro") social factors and individual ("micro") psychological factors, as well as the importance of integrating these factors into suicide prevention programmes at the national level.

Suicide and Transportation Noise: A Prospective Cohort Study from Switzerland

BACKGROUND

Although plausible from a pathophysiological point of view, robust evidence for effects of transportation noise on mental health remains scarce. Meanwhile, psychiatric diseases are among the most prevalent noncommunicable diseases worldwide, and suicide as a mortality outcome highly connected to mental disorders presents a pressing public health issue. The aim of this study was to investigate the association between source-specific transportation noise, particulate matter (PM) air pollution, residential greenness, and suicide by means of a nationwide cohort study.

METHODS

Road traffic, railway and aircraft noise exposure as well as exposure to air pollution [PM with aerodynamic diameter ≤2.5μm (PM2.5)] and greenness [normalized difference vegetation index (NDVI)] were linked to 5.1 million adults (age 15 y and older) in the Swiss National Cohort, accounting for their address history. Mean noise exposure in 5-y periods was calculated. Individuals were followed for up to 15 y (2001-2015). Time-varying Cox regression models were applied to deaths by suicide (excluding assisted suicide). Models included all three noise sources, PM2.5, and NDVI plus individual and spatial covariates, including socioeconomic status. Effect modification by sex, age, socioeconomic indicators, and degree of urbanization was explored.

RESULTS

During the follow-up, there were 11,265 suicide deaths (10.4% poisoning, 33.3% hanging, 28.7% firearms, 14.7% falls). Road traffic and railway noise were associated with total suicides [hazard ratios: 1.040; 95% confidence interval (CI): 1.015, 1.065; and 1.022 (95% CI: 1.004, 1.041) per 10 dB day-evening-night level (Lden)], whereas for aircraft noise, a risk increase starting from 50 dB was masked by an inverse association in the very low exposure range (30-40 dB). Associations were stronger for females than males. The results were robust to adjustment for residential greenness and air pollution.

CONCLUSION

In this longitudinal, nationwide cohort study, we report a robust association between exposure to road traffic and railway noise and risk of death by suicide after adjusting for exposure to air pollution and greenness. These findings add to the growing body of evidence that mental health disorders may be related to chronic transportation noise exposure. https://doi.org/10.1289/EHP11587.

County-level estimates of suicide mortality in the USA: a modelling study

BACKGROUND

Suicide is one of the leading causes of death in the USA and population risk prediction models can inform decisions on the type, location, and timing of public health interventions. We aimed to develop a prediction model to estimate county-level suicide risk in the USA using population characteristics.

METHODS

We obtained data on all deaths by suicide reported to the National Vital Statistics System between Jan 1, 2005, and Dec 31, 2019, and age, sex, race, and county of residence of the decedents were extracted to calculate baseline risk. We also obtained county-level annual measures of socioeconomic predictors of suicide risk (unemployment, weekly wage, poverty prevalence, median household income, and population density) and state-level prevalence of major depressive disorder and firearm ownership from US public sources. We applied conditional autoregressive models, which account for spatiotemporal autocorrelation in response and predictors, to estimate county-level suicide risk.

FINDINGS

Estimates derived from conditional autoregressive models were more accurate than from models not adjusted for spatiotemporal autocorrelation. Inclusion of suicide risk and protective covariates further reduced errors. Suicide risk was estimated to increase with each SD increase in firearm ownership (2·8% [95% credible interval (CrI) 1·8 to 3·9]), prevalence of major depressive episode (1·0% [0·4 to 1·5]), and unemployment rate (2·8% [1·9 to 3·8]). Conversely, risk was estimated to decrease by 4·3% (-5·1 to -3·2) for each SD increase in median household income and by 4·3% (-5·8 to -2·5) for each SD increase in population density. An increase in the heterogeneity in county-specific suicide risk was also observed during the study period.

INTERPRETATION

Area-level characteristics and the conditional autoregressive models can estimate population-level suicide risk. Availability of near real-time situational data are necessary for the translation of these models into a surveillance setting. Monitoring changes in population-level risk of suicide could help public health agencies select and deploy targeted interventions quickly.

FUNDING

US National Institute of Mental Health.

Urban green spaces and suicide mortality in Belgium (2001-2011): A census-based longitudinal study

BACKGROUND

Exposure to green spaces is associated with improved mental health and may reduce risk of suicide. Here, we investigate the association between long-term exposure to residential surrounding greenness and suicide mortality.

METHODS

We used data from the 2001 Belgian census linked to mortality register data (2001-2011). We included all registered individuals aged 18 years or older at baseline (2001) residing in the five largest urban areas in Belgium (n = 3,549,514). Suicide mortality was defined using the tenth revision of the World Health Organisation International Classification of Diseases (ICD-10) codes X60-X84, Y10-Y34, and Y870. Surrounding greenness was measured using the Normalized Difference Vegetation Index (NDVI) within a 300 m and 1,000 m buffer around the residential address at baseline. To assess the association between residential surrounding greenness and suicide mortality, we applied Cox proportional hazards models with age as the underlying time scale. Models were adjusted for age, sex, living arrangement, migrant background, educational attainment, neighbourhood socio-economic position. We additionally explored potential mediation by residential outdoor nitrogen dioxide (NO₂) concentrations. Finally, we assessed potential effect modification by various socio-demographic characteristics of the population (sex, age, educational attainment, migrant background, and neighbourhood socio-economic position). Associations are expressed as hazard ratios and their 95% confidence intervals (CI) for an interquartile range (IQR) increase in residential surrounding greenness.

RESULTS

We observed a 7% (95%CI 0.89-0.97) and 6% (95%CI 0.90-0.98) risk reduction of suicide mortality for an IQR increase in residential surrounding greenness for buffers of 300 m and 1,000 m, respectively. Furthermore, this association was independent of exposure to NO₂. After stratification, the inverse association was only apparent among women, and residents of Belgian origin, and that it was stronger among residents aged 36 or older, those with high level of education, and residents of most deprived neighbourhoods.

CONCLUSION

Our results suggest that urban green spaces may protect against suicide mortality, but this beneficial effect may not be equally distributed across all strata of the population.

Green space and loneliness: A systematic review with theoretical and methodological guidance for future research

Persistent loneliness troubles people across the life span, with prevalence as high as 61 % in some groups. Urban greening may help to reduce the population health impacts of loneliness and its concomitants, such as hopelessness and despair. However, the literature lacks both a critical appraisal of extant evidence and a conceptual model to explain how green space would work as a structural intervention. Both are needed to guide decision making and further research. We conducted a systematic review of quantitative studies testing associations between green space and loneliness, searching seven databases. Twenty two studies were identified by 25/01/2022. Most of the studies were conducted in high-income countries and fifteen (68 %) had cross-sectional designs. Green space was measured inconsistently using either objective or subjective indicators. Few studies examined specific green space types or qualities. The majority of studies measured general loneliness (e.g. using the UCLA loneliness scale). Different types of loneliness (social, emotional, existential) were not analysed. Of 132 associations, 88 (66.6 %) indicated potential protection from green space against loneliness, with 44 (33.3 %) reaching statistical significance (p < 0.05). We integrated these findings with evidence from qualitative studies to elaborate and extend the existing pathway domain model linking green space and health. These elaborations and extensions acknowledge the following: (a) different types of green space have implications for different types of loneliness; (b) multilevel circumstances influence the likelihood a person will benefit or suffer harm from green space; (c) personal, relational, and collective processes operate within different domains of pathways linking green space with loneliness and its concomitants; (d) loneliness and its concomitants are explicitly positioned as mediators within the broader causal system that links green space with health and wellbeing. This review and model provide guidance for decision making and further epidemiological research on green space and loneliness.

Living near coasts is associated with higher suicide rates among females but not males: A register-based linkage study in the Netherlands

Exposure to blue spaces may promote psychological wellbeing and reduce mental distress. Whether these effects extend to suicide is unknown. We used register data from 14 million Dutch adults aged 18-64-years between 2007 and 2016 in a nested case-control study to estimate associations between blue space exposures and suicide risk. Each suicide case was matched to ten randomly selected controls. Two blue space exposures were assigned over a ten-year residential address history: distance to the closest inland blue space and distance to the coast. We fitted (gender-stratified) conditional logistic regressions to the data. Possible effect modifications by income were also examined. In total, our analyses included 9757 cases and 95,641 controls. Effect estimates for distance to the closest inland blue space in the total population showed that people living farthest away from inland blue space were at-risk. Suicide risk was lower among women who lived farther away from the coast; no significant effect was observed for men. No evidence was observed that income modified these associations. Our findings provide suggestive evidence that living close to the coast is associated with greater suicide risk for women, while living closer to inland blue spaces may add to the resilience against suicide in the total population. Past research shows that coastal proximity protects against milder forms of mental illness, but these protective effects do not appear to hold for suicide. Blue space interventions for women with severe mental illness or propensities to engage in self-harm should be approached with caution.

Neighbourhood natural space and the narrowing of socioeconomic inequality in years of life lost: a cross-sectional ecological analysis of the Scottish Burden of Disease

BACKGROUND

Natural space is associated with reduced risk of, and narrower socioeconomic inequalities in, diseases that affect older populations, and some contributors to premature mortality in younger individuals. Burden of disease measures such as years of life lost (YLL) are influenced by premature poor health and death. We hypothesised some association between natural space and both rates of and inequalities in YLL might be present.

METHODS

The outcome data were the YLL component from Scottish Burden of Disease 2016, provided at small-area level (datazone) for males and females under 65 years of age in Scotland, UK. Exposure variables were the percentages of land cover within each datazone defined as 'natural space' (NS), and 'natural space and private gardens' (NSG). Together with a measure of area income deprivation, these were fitted in a multilevel Poisson model accounting for intra-datazone level variation, and spatial autocorrelation between datazones.

RESULTS

An increased percentage cover of NSG was associated with lower YLL in males (incident rate ratio (IRR) 0.993, 95% credible interval (CrI) 0.989 to 0.997) and females (IRR 0.993, CrI 0.987 to 0.998); each 10% increase of natural space cover was associated with a 7% decrease in the incidence rate. An increased amount of natural space within local areas was associated with reduced disparity in YLL between the most and least income deprived areas.

CONCLUSIONS

The health benefits of natural space also apply when indicators sensitive to health events at younger ages are used. An increased amount of natural space within local areas has the potential to reduce the disparity in YLL between the most and least income deprived areas-the 'equigenic' effect.

Urban parks as a potential mitigator of suicide rates resulting from global pandemics: Empirical evidence from past experiences in Seoul, Korea

Globally, the increased suicide rate of the general population has become a concern not only because of the COVID-19 pandemic, but also because of its associated socioeconomic insecurity, loss of jobs, and economic shocks. This study employed robust fixed-effects panel models to empirically identify the mitigating effects of infectious diseases, via urban parks, on the suicide rate, and to examine gender differences in this regard, based on previous experiences in Seoul, Korea. We found that the differentiating mitigating effect did not significantly affect suicide rates during the 2015 MERS epidemic. However, during the 2009 H1N1 pandemic, wherein the number of confirmed cases was very high and diffused nationwide, urban parks significantly reduced the suicide rates for both men and women. The role of parks as a mitigator was more enhanced in cities with a high number of confirmed cases if it was associated with economic shocks. However, this effect was significant only in the suicide rates of men, not women. During a pandemic, urban parks can help maintain social interaction and sustain physical activities (i.e., walking and exercise) while maintaining physical distance. National and local governments should develop urban parks to actively control the suicide rate influenced by movement restriction measures inevitably occurring during the spread of infectious diseases.

Residential green space and mental health-related prescription medication sales: An ecological study in Belgium

BACKGROUND

Residential green space has been associated with mental health benefits, but how such associations vary with green space types is insufficiently known.

OBJECTIVE

We aimed to investigate associations between types and quantities of green space and sales of mood disorder medication in Belgium.

METHODS

We used aggregated sales data of psycholeptics and psychoanaleptics prescribed to adults from 2006 to 2014. Generalized mixed effects models were used to investigate associations between relative covers of woodland, low-green, grassland, and garden, and average annual medication sales. Models were adjusted for socio-economic background variables, urban-rural differences, and administrative region, and included random effects of latitude and longitude.

RESULTS

Urban census tracts were associated with 9-10% higher medication sales. In nationwide models, a 10% increase in relative cover of woodland, garden, and grass was associated with a 1-2% decrease in medication sales. The same association was found for low green but only for men. In stratified models, a 10% increase in relative cover of any green space type in urban census tracts was associated with a decrease of medication sales by 1-3%. In rural census tracts, no protective associations between green space and mood disorder medication sales were observed, with the exception of relative woodland cover for women (-1%), and low green was associated with higher medication sales (+6-7%).

CONCLUSIONS

Taken together, these results suggest that living in green environments may be beneficial for adult mental health. Woodland exposure seemed the most beneficial, but the amount of green space was more important than the type. Results underline the importance of conserving green space in our living environment, for the conservation of biodiversity and for human health.

Examining the Benefits of Greenness on Reducing Suicide Mortality Rate: A Global Ecological Study

Objective

This study applied an ecological-based analysis aimed to evaluate on a global scale the association between greenness exposure and suicide mortality.

Methods

Suicide mortality data provided by the Institute for Health Metrics and Evaluation and the Normalized Difference Vegetation Index (NDVI) were employed. The generalized additive mixed model was applied to evaluate with an adjustment of covariates the association between greenness and suicide mortality. Sensitivity tests and positive-negative controls also were used to examine less overt insights. Subgroup analyses were then conducted to investigate the effects of greenness on suicide mortality among various conditions.

Results

The main finding of this study indicates a negative association between greenness exposure and suicide mortality, as greenness significantly decreases the risk of suicide mortality per interquartile unit increment of NDVI (relative risk = 0.69, 95%CI: 0.59–0.81). Further, sensitivity analyses confirmed the robustness of the findings. Subgroup analyses also showed a significant negative association between greenness and suicide mortality for various stratified factors, such as sex, various income levels, urbanization levels, etc.

Conclusions

Greenness exposure may contribute to a reduction in suicide mortality. It is recommended that policymakers and communities increase environmental greenness in order to mitigate the global health burden of suicide.

Association of stress-related disorders with subsequent risk of all-cause and cause-specific mortality: A population-based and sibling-controlled cohort study

Background

Methods

Findings

Interpretation

Funding

Beneficial Use Impairments, Degradation of Aesthetics, and Human Health: A Review

In environmental programs and blue/green space development, improving aesthetics is a common goal. There is broad interest in understanding the relationship between ecologically sound environments that people find aesthetically pleasing and human health. However, to date, few studies have adequately assessed this relationship, and no summaries or reviews of this line of research exist. Therefore, we undertook a systematic literature review to determine the state of science and identify critical needs to advance the field. Keywords identified from both aesthetics and loss of habitat literature were searched in PubMed and Web of Science databases. After full text screening, 19 studies were included in the review. Most of these studies examined some measure of greenspace/bluespace, primarily proximity. Only one study investigated the impacts of making space quality changes on a health metric. The studies identified for this review continue to support links between green space and various metrics of health, with additional evidence for blue space benefits on health. No studies to date adequately address questions surrounding the beneficial use impairment degradation of aesthetics and how improving either environmental quality (remediation) or ecological health (restoration) efforts have impacted the health of those communities.

Suicide rate and social environment characteristics in South Korea: the roles of socioeconomic, demographic, urbanicity, general health behaviors, and other environmental factors on suicide rate

BACKGROUND

Suicide is a serious worldwide public health concern, and South Korea has shown the highest suicide rate among Organisation for Economic Co-operation and Development (OECD) countries since 2003. Nevertheless, most previous Korean studies on suicide had limitations in investigating various social environment factors using long-term nationwide data. Thus, this study examined how various social environment characteristics are related to the suicide rate at the district-level, using nationwide longitudinal data over 11 years.

METHODS

We used the district-level age-standardized suicide rate and a total of 12 annual social environment characteristics that represented socioeconomic, demographic, urbanicity, general health behaviors, and other environmental characteristics from 229 administrative districts in South Korea. A Bayesian hierarchical model with integrated Laplace approximations (INLA) was used to examine the spatiotemporal association between the rate of suicide and the social environment indicators selected for the study.

RESULTS

In the total population, the indicators "% of population aged 65 and older eligible for the basic pension", "% vacant houses in the area", "% divorce", "% single elderly households", "% detached houses", "% current smokers", and "% of population with obesity" showed positive associations with the suicide rate. In contrast, "% of people who regularly participated in religious activities" showed negative associations with suicide rate. The associations between these social environment characteristics and suicide rate were generally more statistically significant in males and more urbanized areas, than in females and less urbanized areas; however, associations differed amongst age groups, depending on the social environment characteristic variable under study.

CONCLUSIONS

This study investigated the complex role of social environments on suicide rate in South Korea and revealed that higher suicide rates were associated with lower values of socioeconomic status, physical exercise, and religious activities, and with higher social isolation and smoking practice. Our results can be used in the development of targeted suicide prevention policies.

Fatal drowning statistics from the Netherlands - an example of an aggregated demographic profile

Introduction

Incompleteness of fatal drowning statistics is a familiar problem impeding public health measures. Part of the problem may be that only data on accidental drowning are used and not the full potential of accessible data.

Methods

This study combines cause-of-death certificates and public prosecutor’s court documents between 1998 and 2017 to obtain an aggregated profile. Data are also used as a basis for a trend analysis.

Results

The dataset includes 5571 drowned persons (1.69 per 100,000). The highest risk group are persons above the age of 50. Demographic differences are observed between suicide by drowning, accidental drowning, and drowning due to transportation (0.72, 0.64, 0.28 per 100.000) and between native Dutch, and Dutch with western and non-western background (1.46, 1.43, 1.76 per 100.000). Non-residents account for another 12.2%. When comparing the periods 1998–2007 with 2008–2017, the Standard Mortality declines for suicide drowning and accidental drowning among persons with a native Dutch and non-western background. Single regression analysis confirms a decrease of drowning over the full period, breakpoint analysis shows an increase in the incidence of the total number of drowning, suicide by drowning and accidental drowning starting in 2007, 2008 resp. 2012.

Discussion

Compared to the formal number of fatal accidental drowning in the Netherlands (n = 1718; incidence 0.52 per 100,000), the study identifies 350% more drowning. Differences in demographic data and the recent increase needs to be explored for public health interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12620-3.

Exploring the Potential Relationship Between Global Greenness and DALY Loss Due to Depressive Disorders

OBJECTIVE

Prior studies have shown that greenness can reduce the burden of depressive disorders. However, most were focused on local-scale analyses while limited evaluated globally. We aimed to investigate the association between greenness and the burden of depressive disorders using data from 183 countries worldwide.

METHODS

We used the normalized difference vegetation index (NDVI) to estimate greenness. Country-level disability-adjusted life year (DALY) loss due to depressive disorders was used to represent depressive disorder burdens. A generalized linear mixed model was applied to assess the relationship between greenness and depressive disorders after controlling for covariates. Stratified analyses were conducted to determine the effects of greenness across several socio-demographic levels.

RESULTS

The findings showed a significant negative association between greenness and the health burden of depressive disorders with a coefficient of -0.196 (95% CI: -0.356, -0.035) in the DALY changes per interquartile unit increment of NDVI. The stratified analyses suggested beneficial effects of greenness on depressive disorders across sex, various age groups especially for those aged <49 years, with low-income and/or those living in highly urbanized countries.

CONCLUSIONS

Our study noted that greenness exposure was significant negative association with the burden of depressive disorders. The findings should be viewed as recommendations for relevant authorities in supporting environmental greenness enhancement to reduce the mental burdens.

Association between neighborhood environments and suicidal ideation among Korean adults

BACKGROUND

The relationship between neighborhood environments and suicide has not been well studied. In the present study, relations between suicidal ideation and social and physical environments were investigated in Korean adults.

METHODS

This nationwide cross-sectional study was conducted using data from the 2013 Korea Community Health Survey. The final analysis included 221,038 individuals aged ≥ 19 years. A multivariate regression model was used to examine the independent effects of environments on suicidal ideation.

RESULTS

Approximately 9.4% of participants had experienced suicidal ideation. Stepwise multivariate regression analysis showed that trusting neighbors and all five physical environments were independently associated with suicidal ideation. As regards physical environments, relations with suicidal ideation varied across subgroups: satisfaction with overall safety was to be strongly and consistently related to less suicidal ideation.

LIMITATIONS

Causality and the impact of unmeasured confounders were not addressed.

CONCLUSION

Neighborhood environments may reduce suicidal ideation.

A natural experiment reveals impacts of built environment on suicide rate: Developing an environmental theory of suicide

BACKGROUND

Suicide is a global challenge. Although it is clear that socioeconomic and demographic factors influence suicide rates, we know little about the impacts of the built environment on suicide rates.

METHODS

We investigated the relationship between characteristics of the built environment and suicide death rates over a 13-year period in 151 rent-only public housing communities in Hong Kong. The regulations of the public housing authority in Hong Kong constituted a natural experiment with minimal self-selection bias. We conducted hierarchical regression analyses and found that characteristics of the built environment were significantly associated with suicide rates after controlling for SES and demographic factors at the community level.

RESULTS

Three significant environmental factors were identified distance to the nearest urban center, distance to the nearest Mass Transit Railway station, and gross flat area per person.

CONCLUSION

These findings demonstrate a significant association between features of the built environment and suicide rates. They also suggest possible interventions that might reduce suicide through design, or redesign, of the built environment. Lastly, we propose an environmental theory of suicide based on the Interpersonal Theory of Suicide.

Green space and suicide mortality in Japan: An ecological study

Although numerous studies have investigated the effect of green space on mental health, as yet, little is known about the association between green space and suicide. To address this deficit, we conducted the first Japan-wide study of the relationship between green space and suicide mortality. Results from spatial analyses of municipality-level panel data for the 1975-2014 period that included 886,440 suicide deaths with a fixed-effect estimator showed that green space was associated with suicide mortality, and that this relationship was conditioned by the form of greenness, level of urbanity and demographic characteristics. In densely populated cities, park density (parks per 1000 of the population) was associated with reduced suicide mortality among females aged 18 and above and among males aged 18 to 39 and aged 65 and above. In small- and medium-sized cities, park coverage (% by area) was linked to fewer suicide deaths among middle-aged and older females (aged 40 and above). In contrast, in non-cities (rural areas), parks were not associated with suicide mortality whereas woodland coverage (% by area) was linked to reduced suicide deaths among middle-aged and older males (aged 40 and above). Our findings suggest that urban green space and rural forest coverage may have a protective effect against self-harming behavior. Future suicide prevention efforts should consider an increased greening of the residential environment in terms of both availability and accessibility, especially with better designs that accommodate population needs and local conditions.

The influence of residential greenness on mortality in the Asia-Pacific region: a systematic review and meta-analysis

AIMS

To critically appraise the evidence of the impact of exposure to salutogenic green environment on mortality, which is an important endpoint in epidemiological and clinical studies.

METHODS

We searched for studies published and indexed in three databases (PubMed, AMED, and CINAHL Plus) from inception until 31 March 2020, complemented with a search of cited literature for articles describing the effects of greenness on mortality in Asia-Pacific region. Eligible articles were screened and data were extracted independently by two reviewers. A random-effects model was utilised to obtain pool hazard ratio (HR) and risk ratio of all-cause mortality outcome.

RESULTS

The search identified 3239 studies, of which 20 studies reporting 133,363 participants from longitudinal cohort studies and 202 million people from population-based prevalence studies were included in the review. The majority of the studies (60%) were conducted in high-income countries in Asia-Pacific. All participants of the longitudinal cohort studies were aged 60 years or older, whereas the prevalence studies involved people of all age groups. A significant protective association of green environment exposure with all-cause mortality was reported in 18 studies. Pooled results from five studies showed increased level of greenness exposure was associated with a significant decrease in all-cause mortality (pooled HR = 0.97; 95% confidence interval (CI) = 0.93 to 1.02; p < 0.01; I²= 87.8%). Meta-analysis of total number of deaths in different quartiles of green spaces noted decreased risks of mortality with all causes of death with increased surrounding greenness.

CONCLUSIONS

Some limited evidence suggests that populations exposed to the greener environment have a lower risk of mortality, implying the potential role of greenness in increasing longevity. Further studies with standardised design and outcome reporting should be conducted in low- and middle-income countries and in populations of low socioeconomic status to glean more generalisable and complete evidence for public health policy implications.

Suicide along the Australian coast: Exploring the epidemiology and risk factors

Suicide is an increasing global concern with multiple risk factors, yet location-based understanding is limited. In Australia, surf lifesavers (SLS) and lifeguards patrol the coast, performing rescues and assisting injured people, including people who suicide. This study is a descriptive epidemiological analysis of Australian coastal suicide deaths. The results will be used to inform training and support surf lifesaving personnel and suicide prevention organisations. This is a population-based cross-sectional study of suicide deaths at Australian coastal locations (between 1 January 2005 and 31 December 2019). Data were sourced from the National Coronial Information System and SLS Australia's Incident Report Database. Analyses explored decedent, incident, and risk factors by sex and method. Across the study period, there were 666 coastal suicide deaths (71.0% male, 43.4% jumping from high places [X80]). Males were more likely to suicide by other means (hanging, self-poisoning, firearm discharge; n = 145, 83.8%), compared to females who were more likely to suicide by drowning ([X71]; n = 77, 37.7%). In one third (n = 225, 38.3%) toxicology was a contributing factor. The risk of coastal suicides was 10.3 times higher during the seven-days prior to their birthday (p<0.001). Evidence of mental ill health was reported in 61.4% (n = 409) of cases and evidence of suicidal behaviour was reported for 37.4% of decedents (n = 249), more prevalent in females. SLS responded in 10.7% (n = 71) of coastal suicides (most jumps from high places; n = 36, 50.7%). Coastal suicides differ to national trends suggesting that location-based differences should be considered during development of preventative and protective measures, especially at a community level. Accessibility, availability, perceived lethality and symbolic qualities are proposed to influence suicide location decisions. These results will guide support and education strategies for surf lifesaving personnel, contributes to established, ongoing suicide surveillance efforts (including hot-spot identification) and add to the limited literature exploring place-based suicide.

Method-Specific Suicide Rates and Accessibility of Means

Abstract.Background: Few studies have investigated whether means accessibility is related to the spatial distribution of suicide. Aims: To examine the hypothesis that indicators of the accessibility to specific suicide methods were associated with method-specific suicide rates in Taipei City, Taiwan. Method: Smoothed standardized mortality ratios for method-specific suicide rates across 432 neighborhoods and their associations with means accessibility indicators were estimated using Bayesian hierarchical models. Results: The proportion of single-person households, indicating the ease of burning charcoal in the home, was associated with charcoal-burning suicide rates (adjusted rate ratio [aRR] = 1.13, 95% credible interval [CrI] = 1.03–1.25). The proportion of households living on the sixth floor or above, indicating easy access to high places, was associated with jumping suicide rates (aRR = 1.16, 95% CrI, 1.04–1.29). Neighborhoods’ adjacency to rivers, indicating easy access to water, showed no statistical evidence of an association with drowning suicide rates (aRR = 1.27, 95% CrI = 0.92–1.69). Hanging and overall suicide rates showed no associations with any of these three accessibility indicators. Limitations: This is an ecological study; associations between means accessibility and suicide cannot be directly inferred as causal. Conclusion: The findings have implications for identifying high-risk groups for charcoal-burning suicide (e.g., vulnerable individuals living alone) and preventing jumping suicides by increasing the safety of high buildings.

Associations between green/blue spaces and mental health across 18 countries

Living near, recreating in, and feeling psychologically connected to, the natural world are all associated with better mental health, but many exposure-related questions remain. Using data from an 18-country survey (n = 16,307) we explored associations between multiple measures of mental health (positive well-being, mental distress, depression/anxiety medication use) and: (a) exposures (residential/recreational visits) to different natural settings (green/inland-blue/coastal-blue spaces); and (b) nature connectedness, across season and country. People who lived in greener/coastal neighbourhoods reported higher positive well-being, but this association largely disappeared when recreational visits were controlled for. Frequency of recreational visits to green, inland-blue, and coastal-blue spaces in the last 4 weeks were all positively associated with positive well-being and negatively associated with mental distress. Associations with green space visits were relatively consistent across seasons and countries but associations with blue space visits showed greater heterogeneity. Nature connectedness was also positively associated with positive well-being and negatively associated with mental distress and was, along with green space visits, associated with a lower likelihood of using medication for depression. By contrast inland-blue space visits were associated with a greater likelihood of using anxiety medication. Results highlight the benefits of multi-exposure, multi-response, multi-country studies in exploring complexity in nature-health associations.

Virtual Reality Representations of Nature to Improve Well-Being amongst Older Adults: a Rapid Review

Poor well-being amongst older adults poses a serious health concern. Simultaneously, research shows that contact with nature can improve various facets of well-being, including physical, social, and mental well-being. However, nature is not always accessible for older adults due to mobility restrictions and related care needs that come with age. A promising strategy aims at bringing nature inside through pervasive technologies. However, so far, there is little academic understanding of essential nature characteristics, psychological processes involved, and means for implementation in practice. The current study used a three-folded rapid review to assess current understanding and strategies used for improving well-being for older adults through virtual reality representations of nature. Searches were performed across three databases, followed-up by content-based evaluation of abstracts. In total, a set of 25 relevant articles was identified. Only three studies specifically focus on digital nature as an intervention strategy for improving well-being amongst older adults. Although these studies provide useful starting points for the design and (technological) development of such environments, they do not generate understanding of how specific characteristics of virtual nature representations impact social well-being measures in particular, and of the underlying psychological processes involved. We conclude that follow-up research is warranted to close the gap between insights and findings from nature research, gerontology, health research, and human-technology interaction.

Spatial patterns of lower respiratory tract infections and their association with fine particulate matter

This study aimed to identify the spatial patterns of lower respiratory tract infections (LRIs) and their association with fine particulate matter (PM_2.5). The disability-adjusted life year (DALY) database was used to represent the burden each country experiences as a result of LRIs. PM_2.5 data obtained from the Atmosphere Composition Analysis Group was assessed as the source for main exposure. Global Moran's I and Getis-Ord Gi* were applied to identify the spatial patterns and for hotspots analysis of LRIs. A generalized linear mixed model was coupled with a sensitivity test after controlling for covariates to estimate the association between LRIs and PM_2.5. Subgroup analyses were performed to determine whether LRIs and PM_2.5 are correlated for various ages and geographic regions. A significant spatial auto-correlated pattern was identified for global LRIs with Moran's Index 0.79, and the hotspots of LRIs were clustered in 35 African and 4 Eastern Mediterranean countries. A consistent significant positive association between LRIs and PM_2.5 with a coefficient of 0.21 (95% CI 0.06-0.36) was identified. Furthermore, subgroup analysis revealed a significant effect of PM_2.5 on LRI for children (0-14 years) and the elderly (≥ 70 years), and this effect was confirmed to be significant in all regions except for those comprised of Eastern Mediterranean countries.

Blue space, health and well-being: A narrative overview and synthesis of potential benefits

Research into the potential health and well-being benefits from exposure to green spaces such as parks and woodlands has led to the development of several frameworks linking the different strands of evidence. The current paper builds on these to provide a model of how exposure to aquatic environments, or blue spaces such as rivers, lakes and the coast, in particular, may benefit health and well-being. Although green and blue spaces share many commonalities, there are also important differences. Given the breadth of the research, spanning multiple disciplines and research methodologies, a narrative review approach was adopted which aimed to highlight key issues and processes rather than provide a definitive balance of evidence summary. Novel aspects of our framework included the inclusion of outcomes that are only indirectly good for health through being good for the environment, the addition of nature connectedness as both a trait and state, and feedback loops where actions/interventions to increase exposure are implemented. Limitations of the review and areas for future work, including the need to integrate potential benefits with potential risks, are discussed.

Greenery exposure and suicide mortality later in life: A longitudinal register-based case-control study

BACKGROUND

Exposure to residential greenery accumulates over people's lifetimes, and possibly has a protective association with suicide later in life.

OBJECTIVES

To examine the associations between suicide mortality and long-term residential greenery exposure in male and female adults.

METHODS

Our population-based nested case-control study used longitudinally georeferenced Dutch register data. Suicide cases aged 18-64 years between 2007 and 2016 were matched by gender, age, and date of suicide to 10 random controls. We measured long-term greenery exposure along people's 10-year residential address histories through longitudinal normalized difference vegetation indices (NDVI) from Landsat satellite imagery between 1997 and 2016. We assigned accumulated greenery exposures, weighted by people's exposure duration, within 300, 600, and 1,000 m concentric buffers around home addresses. To assess associations between suicide and greenery, we estimated gender-specific conditional logistic regressions without and with adjustment for individual-level and area-level confounders. Stratified models were fitted for areas with a high/low level of urbanicity and movers/non-movers.

RESULTS

Our study population consisted of 9,757 suicide cases and 95,641 controls. In our models adjusted for age, gender, and date of suicide, the odds ratios decreased significantly with higher quartiles of accumulated NDVI scores. NDVI associations were attenuated and did not remain significant after adjustment for socioeconomics, urbanicity, air pollution, social fragmentation, etc. for either males or females. For females, but not males, our model with 300 m buffers for areas with a low level of urbanicity showed a significant suicide risk reduction with increasing levels of NDVI. Individual risk factors (e.g., lack of labor market participation) outweighed the contribution of greenery.

CONCLUSION

We found limited evidence that long-term greenery exposure over people's lifetimes contributes to resilience against suicide mortality. Ensuring exposure to greenery may contribute to suicide prevention for specific population groups, but the effectiveness of such exposure should not be overstated.

A Review of Advancement on Influencing Factors of Acne: An Emphasis on Environment Characteristics

Background: Acne vulgaris is known as a commonly-seen skin disease with a considerable impact on the quality of life. At present, there have been a growing number of epidemiological, medical, demographic and sociological researches focusing on various influencing factors in the occurrence of acne. Nevertheless, the correlation between environmental factors and acne has yet to be fully investigated. Objective: To assess the impacts of individual, natural and social environmental factors on acne and to construct a framework for the potential impact of built environment on acne. Methods: A thorough review was conducted into the published social demographical, epidemiological, and environmental studies on acne through PubMed, Google Scholar and Web of Science, with reference made to the relevant literature. Results: The influencing factors in acne are classed into four major categories. The first one includes individual socio-economic and biological factors, for example, gender, age, economic level, heredity, obesity, skin type, menstrual cycle (for females), diet, smoking, cosmetics products, electronic products, sleep quality and psychological factors. The second one includes such natural environmental factors as temperature, humidity, sun exposure, air pollution and chloracne. The third one relates to social environment, including social network and social media. The last one includes built environmental factors, for example, population density, food stores, green spaces, as well as other built environment characteristics for transport. Acne can be affected negatively by family history, overweight, obesity, oily or mixed skin, irregular menstrual cycles, sugary food, greasy food, dairy products, smoking, the improper use of cosmetics, the long-term use of electronics, the poor quality of sleep, stress, high temperature, sun exposure, air pollution, mineral oils and halogenated hydrocarbons. Apart from that, there are also potential links between built environment and acne. Conclusions: It is necessary to determine the correlation between the built environment and acne based on the understanding of the impact of traditional factors (sociology of population and environment) on acne gained by multidisciplinary research teams. Moreover, more empirical studies are required to reveal the specific relationship between built environment and acne.

Associations between growing up in natural environments and subsequent psychiatric disorders in Denmark

Natural environments have been associated with mental health benefits worldwide. However, how different elements and types of natural environments associate with mental health is still largely unknown. In this study, we perform a detailed analysis on a large, nation-wide data set of mental health records (908 553 individuals) for Denmark combined with remotely-sensed land cover and vegetation density data. We explore associations between growing up surrounded by different environments and rates of a spectrum of 18 psychiatric disorders. Childhood land cover exposure for urban, agricultural, near-natural green space, and blue space was determined around the residence of each individual. Vegetation density and air pollution were evaluated as potential pathways. Cox proportional hazards models were used to estimate rates as hazard ratios and then adjusted for potential confounding from other known risk factors. For 12 of 18 disorders, rates were lower for children growing up in environments with more natural elements (near-natural green space, blue space, and agriculture) compared to children growing up in urban environments. High vegetation density was associated with lower rates for most disorders within all the examined environments, whereas mitigation of air pollution by natural environments seemed a less important potential pathway. Rates were not notably changed by adjustment for urbanization, parental and municipal socioeconomic status, family history of mental illness, and parents' age. In conclusion, we found that growing up surrounded by a range of natural environments such as near-natural green space, blue space, and agriculture may lower rates of psychiatric disorders. Our results show the importance of ensuring access to natural environments from as nature-based solutions for improved public health and sustainable, livable cities.

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

BACKGROUND

There is an increasing volume of literature investigating the links between urban environments and human health, much of which involves spatial conceptualisations and research designs involving various aspects of geographical information science. Despite intensifying research interest, there has been little systematic investigation of pragmatic methodological concerns, such as how studies are realised in terms of the types of data that are gathered and the analytical techniques that are applied, both of which have the potential to impact results. The aim of this systematic review is, therefore, to understand how spatial scale, datasets, methods, and analytics are currently applied in studies investigating the relationship between green and blue spaces and human health in urban areas.

METHOD

We systematically reviewed 93 articles following PRISMA protocol, extracted information regarding different spatial dimensions, and synthesised them in relation to various health indicators.

RESULTS AND DISCUSSION

We found a preponderance of the use of neighbourhood-scale in these studies, and a majority of the studies utilised land-use and vegetation indices gleaned from moderate resolution satellite imagery. We also observed the frequent adoption of fixed spatial units for measuring exposure to green and blue spaces based on physical proximity, typically ranging between 30 and 5000 m. The conceptual frameworks of the studies (e.g., the focus on physical vs. mental health or the definition of exposure to green space) were found to have an influence on the strength of association between exposure and health outcomes. Additionally, the strength and significance of associations also varied by study design, something which has not been considered systematically.

CONCLUSION

On the basis of our findings, we propose a set of recommendations for standardised protocols and methods for the evaluation of the impact of green-blue spaces on health. Our analysis suggests that future studies should consider conducting analyses at finer spatial scales and employing multiple exposure assessment methods to achieve a comprehensive and comparable evaluation of the association between greenspace and health along multiple pathways.

​Is suicide mortality associated with neighbourhood social fragmentation and deprivation? A Dutch register-based case-control study using individualised neighbourhoods

Background

Neighbourhood social fragmentation and socioeconomic deprivation seem to be associated with suicide mortality. However, results are inconclusive, which might be because dynamics in the social context are not well-represented by administratively bounded neighbourhoods at baseline. We used individualised neighbourhoods to examine associations between suicide mortality, social fragmentation, and deprivation for the total population as well as by sex and age group.

Methods

Using a nested case-control design, all suicides aged 18–64 years between 2007 and 2016 were selected from longitudinal Dutch register data and matched with 10 random controls. Indices for social fragmentation and deprivation were calculated annually for 300, 600 and 1000 metre circular buffers around each subject’s residential address.

Results

Suicide mortality was significantly higher in neighbourhoods with high deprivation and social fragmentation. Accounting for individual characteristics largely attenuated these associations. Suicide mortality remained significantly higher for women living in highly fragmented neighbourhoods in the fully adjusted model. Age-stratified analyses indicate associations with neighbourhood fragmentation among women in older age groups (40–64 years) only. Among men, suicide risk was lower in fragmented neighbourhoods for those aged 18–39 years and for short-term residents. In deprived neighbourhoods, suicide risk was lower for men aged 40–64 years and long-term residents. Associations between neighbourhood characteristics and suicide mortality were comparable across buffer sizes.

Conclusion

Our findings suggest that next to individual characteristics, the social and economic context within which people live may both enhance and buffer the risk of suicide.

Effects of greenspace morphology on mortality at the neighbourhood level: a cross-sectional ecological study

BACKGROUND

The association between urban greenspace and mortality risk is well known, but less is known about how the spatial arrangement of greenspace affects population health. We aimed to investigate the relation between urban greenspace distribution and mortality risk.

METHODS

We did a cross-sectional study in Philadelphia, PA, USA, using high-resolution landcover data for 2008 from the Pennsylvania Spatial Data Access database. We calculated landscape metrics to measure the greenness, fragmentation, connectedness, aggregation, and shape of greenspace, including and omitting green areas 83·6 m² or smaller, using Geographical Information System and spatial pattern analysis programs. We analysed all-cause and cause-specific mortality (related to heart disease, chronic lower respiratory diseases, and neoplasms) recorded in 2006 for 369 census tracts (small geographical areas with a population of 2500-8000 people). We did negative binomial regression and principal component analyses to assess associations between landscape spatial metrics and mortality, controlling for geographical, demographic, and socioeconomic factors.

FINDINGS

A 1% increase in the percentage of greenspace was predicted to reduce all-cause mortality by 0·419% (95% CI 0·050-0·777), with no effect on cause-specific mortality. All-cause mortality was negatively associated with the area of greenspace. A 1 m² increase in the mean area of greenspace led to a 0·011% (95% CI 0·004-0·018) fall in all-cause mortality and a 0·019% (0·007-0·032) decrease in cardiac mortality; considering only green areas larger than 83·6 m² would contribute to a 0·002% (95% CI 0·001-0·003) decrease in all-cause mortality and a 0·003% (0·001-0·006) reduction in cardiac deaths. Census tracts with more connected, aggregated, coherent, and complex shape greenspaces had a lower risk of all-cause and cause-specific mortality. The negative association between articulated landscape parcels and all-cause mortality varied with age and education, such that the relation was stronger for census tracts with a higher percentage of older and less well-educated adults.

INTERPRETATION

A significant modest association exists between the spatial distribution of greenspace in cities and mortality risk. The overall amount of greenspace alone is probably failing to capture significant variance in local health outcomes and, thus, environment-based health planning should consider the shape, form, and function of greenspace.

FUNDING

None.

The effect of short-term exposure to the natural environment on depressive mood: A systematic review and meta-analysis

BACKGROUND

Research suggests that exposure to the natural environment can improve mood, however, current reviews are limited in scope and there is little understanding of moderators.

OBJECTIVE

To conduct a comprehensive systematic review and meta-analysis of the evidence for the effect of short-term exposure to the natural environment on depressive mood.

METHODS

Five databases were systematically searched for relevant studies published up to March 2018. Risk of bias was evaluated using the Cochrane Risk of Bias (ROB) tool 1.0 and the Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) tool where appropriate. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach was used to assess the quality of evidence overall. A random-effects meta-analysis was performed. 20 potential moderators of the effect size were coded and the machine learning-based MetaForest algorithm was used to identify relevant moderators. These were then entered into a meta-regression.

RESULTS

33 studies met the inclusion criteria. Effect sizes ranged from -2.30 to 0.84, with an unweighted mean effect size of M_g=-0.29,SD=0.60. However, there was significant residual heterogeneity between studies and risk of bias was high. Type of natural environment, type of built environment, gender mix of the sample, and region of study origin, among others, were identified as relevant moderators but were not significant when entered in a meta-regression. The quality of evidence was rated very low to low. An assessment of publication bias was inconclusive.

CONCLUSIONS

A small effect was found for reduction in depressive mood following exposure to the natural environment. However, the high risk of bias and low quality of studies limits confidence in the results. The variation in effect size also remains largely unexplained. It is recommended that future studies make use of reporting guidelines and aim to reduce the potential for bias where possible.

Dynamic Urban Environmental Exposures on Depression and Suicide (NEEDS) in the Netherlands: a protocol for a cross-sectional smartphone tracking study and a longitudinal population register study

INTRODUCTION

Environmental exposures are intertwined with mental health outcomes. People are exposed to the environments in which they currently live, and to a multitude of environments along their daily movements and through their residential relocations. However, most research assumes that people are immobile, disregarding that such dynamic exposures also serve as stressors or buffers potentially associated with depression and suicide risk. The aim of the Dynamic Urban Environmental Exposures on Depression and Suicide (NEEDS) study is to examine how dynamic environmental exposures along people's daily movements and over their residential histories affect depression and suicide mortality in the Netherlands.

METHODS AND ANALYSIS

The research design comprises two studies emphasising the temporality of exposures. First, a cross-sectional study is assessing how daily exposures correlate with depression. A nationally representative survey was administered to participants recruited through stratified random sampling of the population aged 18-65 years. Survey data were enriched with smartphone-based data (eg, Global Positioning System tracking, Bluetooth sensing, social media usage, communication patterns) and environmental exposures (eg, green and blue spaces, noise, air pollution). Second, a longitudinal population register study is addressing the extent to which past environmental exposures over people's residential history affect suicide risk later in life. Statistical and machine learning-based models are being developed to quantify environment-health relations.

ETHICS AND DISSEMINATION

Ethical approval (FETC17-060) was granted by the Ethics Review Board of Utrecht University, The Netherlands. Project-related findings will be disseminated at conferences and in peer-reviewed journal papers. Other project outcomes will be made available through the project's web page, http://www.needs.sites.uu.nl.

The vulnerability paradox in global mental health and its applicability to suicide

BACKGROUND

Previous research has identified a vulnerability paradox in global mental health: contrary to positive associations at the individual level, lower vulnerability at the country level is accompanied by a higher prevalence in a variety of mental health problems in national populations. However, the validity of the paradox has been challenged, specifically for bias from modest sample sizes and reliance on a survey methodology not designed for cross-national comparisons.AimsTo verify whether the paradox applies to suicide, using data from a sizable country sample and an entirely different data source.

METHOD

We combined data from the World Health Organization 2014 suicide report and the country vulnerability index from the 2016 World Risk Report. Suicide was predicted in different steps based on gender, vulnerability and their interaction, World Bank income categories, and suicide data quality.

RESULTS

A negative association between country vulnerability and suicide prevalence in both women and men was found. Suicide rates were higher for men, regardless of country vulnerability. The model predicting suicide in 96 countries based on gender, vulnerability, income and data quality had the best goodness-of-fit compared with other models. The vulnerability paradox is not accounted for by income or data quality, and exists across and within income categories.

CONCLUSIONS

The study underscores the relevance of country-level factors in the study of mental health problems. The lower mental disorder prevalence in more vulnerable countries implies that living in such countries fosters protective factors that more than compensate for the limitations in professional healthcare capacity.Declaration of interestNone.

Spatiotemporal Contextual Uncertainties in Green Space Exposure Measures: Exploring a Time Series of the Normalized Difference Vegetation Indices

Environmental health studies on green space may be affected by contextual uncertainties originating from the temporality of environmental exposures and by how the spatial context is delimitated. The Normalized Difference Vegetation Index (NDVI) is frequently used as an outdoor green space metric capturing the chlorophyll content in the vegetation canopy. This study assessed (1) whether residential NDVI exposures vary over time, and (2) how these time series of NDVI scores vary across spatial context delimitations. Multi-temporal NDVI data for the period 2006–2017 for the Netherlands were obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite platform. Annual NDVI exposures were determined across multiple buffer sizes (i.e., 300, 600, and 1000 m) centered on a random sample of 10,000 Dutch residential addresses. Besides the descriptive statistics, pairwise Wilcoxon tests and Fligner–Killeen tests were used to determine mean and variance differences in annual NDVI scores across buffer widths. Heat maps visualized the correlation matrices. Significance levels were adjusted for multiple hypotheses testing. The results indicated that annual NDVI metrics were significantly correlated but their magnitude varied notably between 0.60 to 0.97. Numerous mean and variance differences in annual NDVI exposures were significant. It seems that the disparate buffers (i.e., 300 and 1000 m) were less strongly correlated, possibly because variance heterogeneity is reduced in larger buffers. These results have been largely consistent over the years and have passed Monte Carlo-based sensitivity tests. In conclusion, besides assessing green space exposures along different buffer sizes, our findings suggest that green space–health studies should employ NDVI data that are well-aligned with epidemiological data. Even an annual temporal incompatibility may obscure or distort green space–health associations. Both strategies may diminish contextual uncertainties in environmental exposure assessments.

The Economic Case for the Prevention of Mental Illness

Poor mental health has profound economic consequences. Given the burden of poor mental health, the economic case for preventing mental illness and promoting better mental health may be very strong, but too often prevention attracts little attention and few resources. This article describes the potential role that can be played by economic evidence alongside experimental trials and observational studies, or through modeling, to substantiate the need for increased investment in prevention. It illustrates areas of action across the life course where there is already a good economic case. It also suggests some further areas of substantive public health concern, with promising effectiveness evidence, that may benefit from economic analysis. Financial and economic barriers to implementation are then presented, and strategies to address the barriers and increase investment in the prevention of mental illness are suggested.

Does Residential Green and Blue Space Promote Recovery in Psychotic Disorders? A Cross-Sectional Study in the Province of Utrecht, The Netherlands

Mental health is reportedly influenced by the presence of green and blue space in residential areas, but scientific evidence of a relation to psychotic disorders is scant. We put two hypotheses to the test: first, compared to the general population, psychiatric patients live in neighborhoods with less green and blue space; second, the amount of green and blue space is negatively associated with the duration of hospital admission. The study population consisted of 623 patients with psychotic disorders who had been admitted to the psychiatric ward of an academic hospital in Utrecht, The Netherlands from 2008 to 2016. Recovery was measured by length of stay. Structured patient data was linked to socio-economic status and the amount of green and blue space in the residential area. Associations were assessed by means of regression models controlling for confounding factors. Compared to the general population, psychiatric patients had a significantly lower amount of green space in their neighborhood. This result was not confirmed for blue space. Furthermore, no significant associations were found between green and blue space and the duration of hospital stay. In conclusion, previous studies focusing on other mental disorders, like anxiety or depression, found positive mental health effects of green and blue space in the neighborhood. We were not able to confirm significant effects among our study population on duration of admission, however. Future research focusing on psychotic patients could investigate the influence of exposure to green and blue space on other influences and outcomes on mental health.