Green space and child weight status : does outcome measurement matter? Evidence from an Australian longitudinal study

Taren Sanders is supported by an Australian Postgraduate Award. Thomas Astell-Burt is supported by a Fellowship with the National Heart Foundation of Australia.Objective. To examine whether neighbourhood green space is beneficially associated with (i) waist circumference (WC) and (ii) waist-to-height ratio (WtHR) across childhood. Methods. Gender-stratified multilevel linear regressions were used to examine associations between green space and objective measures of weight status in the Longitudinal Study of Australian Children, a nationally representative source of data on 4,423 children aged 6 y to 13 y. WC and WtHR were measured objectively. Percentage green space within the local area of residence was calculated. Effect modification by age was explored, adjusting for socioeconomic confounding. Results. Compared to peers with 0-5% green space locally, boys and girls with >40% green space tended to have lower WC (βboys -1.15, 95% CI -2.44, 0.14; βgirls -0.21, 95% CI -1.47, 1.05) and WtHR (βboys -0.82, 95% CI -1.65, 0.01; βgirls -0.32, 95% CI -1.13, 0.49). Associations among boys were contingent upon age (p valuesage green space40% green space at 73.85 cm and 45.75% compared to those with 0-5% green space at 75.18 cm and 46.62%, respectively. Conclusions. Greener neighbourhoods appear beneficial to alternative child weight status measures, particularly among boys.Publisher PDFPeer reviewe

Does rising crime lead to increasing distress? Longitudinal analysis of a natural experiment with dynamic objective neighbourhood measures

Identifying ‘neighbourhood effects’ to support widespread beliefs that where we live matters for our health remains a major challenge due to the reliance upon observational data. In this study we reassess the issue of local crime rates and psychological distress by applying unobserved bias models to a sample of participants who remain in the same neighbourhoods throughout the study. Baseline data was extracted from the 45 and Up Study between 2006 and 2008 and followed up as part of the Social Economic and Environmental Factors (SEEF) Study between 2009 and 2010. Kessler 10 scores were recorded for 25 545 men and 29 299 women reported valid outcomes. Annual crime rates per 1,000 (including non-domestic violence, malicious damage, break and enter, and stealing, theft and robbery) from 2006 to 2010 inclusive were linked to the person-level data. Change in exposure to crime among participants in this study, therefore, occurs as a result of a change in the local crime rate, rather than a process of neighbourhood selection. Gender stratified unobserved bias logistic regression adjusting for sources of time-varying confounding (age, income, employment, couple status and physical functioning) indicated that an increase in the risk of experiencing psychological distress was generally associated with an increase in the level of neighbourhood crime. Effect sizes were particularly high for women, especially for an increase in malicious damage (Odds Ratio Tertile 3 vs Tertile 1 2.40, 95% Confidence Interval 1.88, 3.05), which may indicate that damage to local built environment is an important pathway linking neighbourhood crime with psychological distress. No statistically significant association was detected for an increase in non-domestic violence, although the effect was in the hypothesised direction. In summary, the application of unobserved bias models to analyse data that takes into account the temporally dynamic characteristics of where people live warrants further investigation.PostprintPeer reviewe

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Greener neighbourhoods, healthier lives? Evidence from Britain

If physical activity (PA) is an important mechanism linking exposure to green space with better mental and physical health, the well-known decline in PA across the lifecourse would suggest that the association between green space and health weakens with age. Few studies, however, have examined this hypothesis. This study examined the interaction between green space, physical activity, and mental health across the lifecourse

A comparison of green space indicators for epidemiological research

Background The potential for natural environments to be salutogenic has received growing interest from epidemiologists, but there has been no critical examination of the extent to which associations between green space and health might vary according to the indicator of green space coverage used.Methods Three different indicators of green space coverage were derived for a set of 268 small areas in four cities within Britain. The indicators had different origins and provided a spectrum of sensitivity from larger spaces only, through to ambient greenery. Two indicators reproducible for anywhere in Europe were included. Agreement between the indicators on the quantity of green space in a small area, and their independent association with measures of mortality and self-reported morbidity, were compared.Results Overall, the indicators showed relatively close overall agreement (all r2>0.89, p<0.001). However, agreement varied by level of area socioeconomic deprivation (p<0.001). The indicator that detected larger spaces only found less green space in areas of socioeconomic deprivation than the other two. Despite this difference, all indicators showed similar protective associations with the risk of mortality and self-reported morbidity suggesting that larger green spaces may be more important for health effects than smaller spaces.Conclusions Associations between green space indicator and health were not sensitive to indicator origin and type. This raises the possibility of trans-European epidemiological studies. Larger green spaces may be the most important for health effects, but may also be less prevalent in more deprived areas

Geographies of hepatitis C: exploring the extent to which geographic accessibility to healthcare influences outcomes amongst individuals infected with Hepatitis C in NHS Tayside, Scotland

Millions of people are infected with the Hepatitis C Virus (HCV) worldwide. In the UK, many individuals continue to live with undiagnosed HCV infection and are increasingly at risk of developing life-threatening cirrhosis and liver cancer. Of those that are diagnosed, only some are referred to an HCV specialist centre where vital treatment could cure their infection. Of those that are referred, only a proportion have actually attended and stayed in follow-up with a specialist centre. Geographic access to healthcare may be an important factor in these trends, but has so far received little attention in the context of HCV. This thesis examines the influence of geographic access to primary and specialist healthcare on HCV detection, trends of referral, chances of specialist centre utilisation and the odds of staying in follow-up. It also explores association between geographic access and the type of location in which diagnoses were made with the risk of mortality from liver-related causes. HCV detection was lower amongst those with poorer geographic access to primary healthcare, but further analyses suggest this trend is due to selection, not causation. Individuals with the furthest to travel were less likely to be referred to an HCV specialist centre, compared to those who lived closer. Travel-time was not a significant predictor of utilisation of HCV specialist centres, but with patients in more remote areas less likely to be referred, it is probable that the utilisation result is biased due to selection. Liver-related mortality was higher for patients diagnosed in hospitals, but the risk of death was not associated with a lack of geographic access to healthcare

Investigating ‘place effects’ on mental health:implications for population-based studies in psychiatry

Interest in features of our local environments that may promote better mental health and wellbeing continues to rise among decision makers. Our purpose was to highlight a selection of these challenges and some promising avenues for enhancing the quality of evidence. Method. An analysis of approximately 267, 000 people was used to test the local relative deprivation hypothesis, wherein the shortfall of a person's socioeconomic circumstances from their neighbours is said to impact negatively upon mental health. This case was used to anchor further discussion of challenges to identifying and interpreting genuine 'place effects' from spurious correlations. Results. A Median Odds Ratio of 1.29 computed via multilevel logistic regression showed that the odds of experiencing psychological distress (as measured by the Kessler score) varied by geographical area. Approximately 67% of this was attributed to a cross-classified measure of household income and neighbourhood deprivation. Compared to people on high incomes living in affluent neighbourhoods, the odds ratio of psychological distress for people on low incomes in affluent areas was 4.73 (95% confidence interval (95% CI) 4.39, 5.09), whereas that for people on low incomes in deprived areas was significantly higher at 5.83 (95% CI 5.41, 6.28). Conclusions. While no evidence was found to support local relative deprivation hypothesis, the pattern suggests that more affluent areas may contain features that are conducive to better mental health. Selection of bespoke geographical boundaries, use of directed acyclic graphs and more evaluations of natural experiments are likely to be important in taking the field of enquiry onwards