Nicholas John Osborne

Background Studies, including umbrella reviews, have provided evidence linking greenspace exposure to specific health outcomes. To address methodological limitations in existing umbrella reviews, this umbrella review aims to expand knowledge on the association between greenspace and human health by summarising evidence from both quantitative and qualitative systematic reviews and meta-analyses. Methods This umbrella review builds upon our previous review with updates to reflect recent developments in the field. Five databases (PubMed, Embase, the Cumulative Index to Nursing and Allied Health Literature [CINAHL], Scopus, and the Cochrane Database of Systematic Reviews) were searched for articles published in English in peer-reviewed journals between December 2020 and June 2024. Systematic reviews and meta-analyses were included if they clearly defined measures of greenspace exposure and reported health outcomes directly attributable to greenspace exposure (PROSPERO: CRD42022383421). The methodological quality and risk of bias of each included review were evaluated by two independent reviewers. Results A total of 45 articles were included in this umbrella review. Greenspace exposure was beneficially associated with mental health, general health and quality of life, and cardiovascular and metabolic health. Inconsistent or inconclusive associations were observed for respiratory health and allergies, maternal health and birth outcomes, cancer, and cognitive function. Some harmful associations were reported for communicable and vector-borne diseases, although these were based on a limited number of systematic reviews. Most of the included reviews had a high risk of bias and critically low methodological quality. Discussion This umbrella review highlights the multifaceted health benefits of greenspace exposure while underlining existing evidence gaps and methodological challenges. The results indicate that increasing access to greenspace could be a simple and cost-effective strategy to improve population health and reduce health inequalities.

Introduction: Recurrent climate hazards place considerable and compounding strain on the mental health of rural communities. These effects are shaped by interconnected social, economic, and service factors, yet policy responses often remain fragmented and short term. Aim: This study sought to identify key system dynamics influencing mental health in a rural Australian community exposed to multiple climate hazards, and to highlight leverage points for more effective policy and service responses. Methods: A qualitative systems approach was used, combining stakeholder interviews with group model building to develop a causal loop diagram (CLD). Participants included community members, service providers, and local stakeholders. The CLD mapped relationships between climate stressors and mental health outcomes across sectors. Results: The model identified reinforcing feedback loops linking social isolation, psychological distress, and reduced help-seeking. Key drivers included declining agricultural productivity, financial stress, workforce shortages, and service disruption from short-term funding. Cultural barriers to care further limited access. Protective factors, including social cohesion and local leadership, mitigated some impacts. Trust in services and institutions emerged as a critical mediator of engagement and recovery. Conclusion: Strengthening rural mental health under climate change requires sustained, systems-oriented, and locally embedded policy and service responses.

This study quantifies the lagged association between grass pollen exposure and the onset of allergic rhinitis (AR) symptoms, including differences between asthmatic and non‐asthmatic subgroups. Data included 114,834 self‐reported AR symptoms collected from 25,194 uniquely identified users of a smartphone application. Reports were gathered prospectively for seven consecutive grass pollen seasons (2017–2023) in Melbourne. We adjusted for meteorological, air quality, and other time‐varying covariates. A quasi‐Poisson regression model combined with a distributed lag non‐linear model (DLNM) was used, testing 0–7 days lagged effects. An association between grass exposure and daily AR incidence of any severity was observed on “low” exposure days (19 grains/m ³ ), when exposure was modeled cumulatively across a 3‐day lag period (RR 1.31, 95% CI 1.16–1.47). Higher grass concentrations were associated with increased risk at lag‐1, with risk rising from RR 1.08 (95% CI 0.99–1.17) at 19 grains/m ³ to RR 1.19 (95% CI 1.09–1.29) at 150 grains/m ³ . By lag‐2, risk returned to a non‐significant baseline. Asthmatics, users reporting medication use, and users reporting more severe symptoms exhibited elevated risk at later lags. The magnitude and duration of elevated risk varied across stratified models by age and sex. We provide new population‐level evidence that grass pollen triggers allergic rhinitis symptoms predominately on the day of exposure, even at concentrations traditionally classified as “low”, with symptom risk persisting longer in asthmatics and other sensitive groups. This study highlights the value of refining communication and early‐warning systems to better support individuals who are sensitive to even low levels of exposure.

Existing longitudinal studies examining the relationship between greenspace exposure and incidence of type-2 diabetes (T2D) have primarily operationalized greenspace using vegetation indices. Little is known about the effect of greenspace types (e.g., private gardens) and public park access. We investigated the associations between residential greenspace exposure, including private gardens (determined using Ordnance Survey MasterMap™ Greenspace) and public park access, with the incidence of T2D using the UK Biobank (UKBB) data. Public park access, such as nearest distances (i.e., walkable road network and Euclidean), and the number of parks were calculated for each participant. The incidence of T2D was ascertained through linkage of hospital admissions data. Cox proportional hazard models, adjusting for covariates, were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI). We also performed stratified analyses by age, sex, neighbourhood deprivation, and family history of diabetes. Of the 423,282 UKBB participants (mean age:56.36 years) included in the study, 19,648 developed T2D over a median follow-up of 15.41 years. Compared to the first quartile, participants in the highest quartile of private garden cover (%) had a reduced risk of T2D (HR: 0.932; 95%CI: 0.88, 0.983). For park access, nearest distance (whether walkable or Euclidean) was not associated with the incidence of T2D. However, having a higher number of parks, particularly three or more parks within an 800-m buffer of the home location, was found to lower the incidence of T2D (HR: 0.943; 95% CI: 0.906, 0.981). Stratified analyses revealed that the beneficial effects of private gardens were stronger among participants in deprived areas and those without a family history of diabetes. Private residential gardens exposure (often overlooked in greenspace-health research) and a higher number of parks around homes were found to lower the incidence of T2D. This has implications for urban planning and public health, particularly in the prevention and management of diabetes.

Background Studies, including umbrella reviews, have provided evidence linking greenspace exposure to specific health outcomes. To address methodological limitations in existing umbrella reviews, this umbrella review aims to expand knowledge on the association between greenspace and human health by summarising evidence from both quantitative and qualitative systematic reviews and meta-analyses. Methods This umbrella review builds upon our previous review with updates to reflect recent developments in the field. Five databases (PubMed, Embase, the Cumulative Index to Nursing and Allied Health Literature [CINAHL], Scopus, and the Cochrane Database of Systematic Reviews) were searched for articles published in English in peer-reviewed journals between December 2020 and June 2024. Systematic reviews and meta-analyses were included if they clearly defined measures of greenspace exposure and reported health outcomes directly attributable to greenspace exposure (PROSPERO: CRD42022383421). The methodological quality and risk of bias of each included review were evaluated by two independent reviewers. Results A total of 45 articles were included in this umbrella review. Greenspace exposure was beneficially associated with mental health, general health and quality of life, and cardiovascular and metabolic health. Inconsistent associations were observed for respiratory health and allergies, maternal health and birth outcomes, and cancer. Most of the included reviews had a high risk of bias and critically low methodological quality. Discussion This umbrella review highlights the multifaceted health benefits of greenspace exposure while underlining existing evidence gaps and methodological challenges. The results indicate that increasing access to greenspace could be a simple and cost-effective strategy to improve population health and reduce health inequalities.

Exposure to heat during pregnancy may increase the risk of adverse birth outcomes, particularly in low- and middle-income countries (LMIC) where healthcare access and adaptive capacity are limited. Here, using a generalised logistic mixed model where potential confounders were adjusted for, we examined the impact of extreme heat stress (defined as the number of consecutive sweltering days throughout the gestational period) on preterm birth (PTB), low birth weight (LBW), stillbirth (SB), and miscarriages (MC) in women aged 15-49 years in India from 2015 to 2020 leveraging a nationally representative population sample from India’s National Family Health Survey. Among 209,266 participants, we identified 29873 LBW, 2341 PTB, 1740 SB, and 13789 MC cases. Each additional day of consecutive ‘sweltering’ in-utero heat exposure was associated with increased risks of LBW (OR: 1.010, 95% CI: 1.001–1.018), Late Pregnancy loss (OR:1.002 ,95% CI: 1.001–1.003). Further, heat exposure during the trimester specific exposure window was with increased odds for PTB (OR: 1.036, 95% CI: 1.009–1.064) in first trimester, LBW(OR: 1.010, 95% CI: 1.002–1.018) in second trimester, pregnancy loss (OR: 1.018, 95% CI: 1.006–1.030) in third trimester, compared to unexposed mothers. Our findings indicate that exposure to ambient heat extremes was associated with adverse pregnancy outcomes in India, and the effect varied depending on the exposure window during pregnancy. With climate change projected to increase the frequency of heat extremes, effective adaptation strategies are necessary to minimise these adverse health effects.

To investigate the association between asthma and the risk of mental health problems in Australian men, and to assess the influence of age on this association. Data from 16,021 men aged 10 to 37 years participating in the Ten to Men the Australian Longitudinal Study on Male Health was analysed. Logistic regression models and generalised estimating equations (GEE) were used to examine the relationship between asthma and anxiety, depression and hazardous alcohol consumption. Stratified models were conducted to explore the impact of age on this association, dividing participants into three groups: Boys aged 10 to 17 years; Young adults aged 18 to 30 years; and Adults aged 31 to 57 years. Men with asthma have 68% higher risk of developing anxiety compared to non-asthmatic men in adjusted models. The risk of anxiety was highest in the young adult group (OR (CI 95%) = 2.15 (1.56- 2.96)). An association between asthma and depression was also identified (OR= 1.39, 95% CI= 1.11,1.73) and adults (men aged 31 to 57 years) were at higher risk (OR= 1.33, 95% CI= 1.02,1.72). Asthma was not associated with hazardous alcohol consumption in the overall population or within any specific age group. Australian men with asthma have a greater risk of developing anxiety and depression. The findings contribute to understanding sex-specific impacts of asthma on mental health and identify men at higher risk of anxiety and depression. Our study also provides research evidence to support frequent psychological monitoring in men with asthma.

Heatwave-health vulnerability index (HVI) map is an important tool for mitigating heatwave. However, the perspectives of heatwave-health management professionals (HMPs) about heatwave vulnerability have not been examined. This study aims to understand HMP's perception and experiences of applying the HVI tool for heatwave-related health adaptation and mitigation. A semi-structured interview with HMPs was conducted between June and October 2024 across the Australian state agencies. We conducted an online interview, which lasted ∼31 minutes. Participants were asked to share their perspectives about the HVI tool, its policy applications, challenges, and recommendations. Twenty HMPs, the majority (75%) within 40–59 years old, 10 female (50%), and with a median (range) heat-health work experience of 6 (2–11) years participated in the study. The HMPs were from Health (50%), Climate/Environment (15%), Emergency Services (10%), Meteorology (10%), and City Councils (15%). The five themes identified were the following: (i) HMPs have moderate levels of awareness of heatwave vulnerability, particularly in the context of locating the hottest areas, (ii) HVI is considered an important tool for heatwave planning, public information, and urban design, (iii) adherence to traditional heat management strategies, low national awareness, and resourcing problems are perceived as key barriers to a national HVI, (iv) the current HVI is faced with methodological inconsistencies, limited understanding, and low confidence among policymakers, and (v) HMP are well positioned to evaluate HVI and encourage broader engagement of the index in Australia. This study offers critical insight for improving policy awareness and enhances the evaluation of the HVI through a multidisciplinary approach.