Advancing urban mental health research: from complexity science to actionable targets for intervention.

Urbanisation and common mental disorders (CMDs; ie, depressive, anxiety, and substance use disorders) are increasing worldwide. In this Review, we discuss how urbanicity and risk of CMDs relate to each other and call for a complexity science approach to advance understanding of this interrelationship. We did an ecological analysis using data on urbanicity and CMD burden in 191 countries. We found a positive, non-linear relationship with a higher CMD prevalence in more urbanised countries, particularly for anxiety disorders. We also did a review of meta-analytic studies on the association between urban factors and CMD risk. We identified factors relating to the ambient, physical, and social urban environment and showed differences per diagnosis of CMDs. We argue that factors in the urban environment are likely to operate as a complex system and interact with each other and with individual city inhabitants (including their psychological and neurobiological characteristics) to shape mental health in an urban context. These interactions operate on various timescales and show feedback loop mechanisms, rendering system behaviour characterised by non-linearity that is hard to predict over time. We present a conceptual framework for future urban mental health research that uses a complexity science approach. We conclude by discussing how complexity science methodology (eg, network analyses, system-dynamic modelling, and agent-based modelling) could enable identification of actionable targets for treatment and policy, aimed at decreasing CMD burdens in an urban context.

Exploring the Relationship Between Air Quality and Ischemic Stroke Admissions During the COVID-19 Pandemic.

OBJECTIVES: Amongst all the global catastrophe due to Coronavirus disease 2019, a significant bright spot is a reduction in air pollution as countries undergo lockdowns to limit the spread of infection. Another reduction that has been reported is in the number of strokes presenting to hospitals, despite the virus implicated in causing a hypercoagulable state. Acute exposure to air pollution has been linked to increase in stroke incidence and the improvement in air quality may be responsible for the decrease in stroke presentations. MATERIALS AND METHODS: To explore this hypothesis, we compared the air quality index (AQI) of Karachi, the largest cosmopolitan city of Pakistan, during the lockdown period in 2020 to the same period in the previous year. RESULTS: We found a significant drop in AQI depicting an improvement in air quality. Simultaneously, we identified a drop in number of stroke admissions to less than half from 2019 to 2020 at one of the largest tertiary care hospitals of the city, during this period of interest. CONCLUSION: We hypothesize that one important reason for this drop in stroke admissions, may be an actual reduction in stroke incidence brought about by an improvement in air quality.

Strong variations in urban allergenicity riskscapes due to poor knowledge of tree pollen allergenic potential.

Exposure to allergenic tree pollen is an increasing environmental health issue in urban areas. However, reliable, well-documented, peer-reviewed data on the allergenicity of pollen from common tree species in urban environments are lacking. Using the concept of 'riskscape', we present and discuss evidence on how different tree pollen allergenicity datasets shape the risk for pollen-allergy sufferers in five cities with different urban forests and population densities: Barcelona, Montreal, New York City, Paris, and Vancouver. We also evaluate how tree diversity can modify the allergenic risk of urban forests. We show that estimates of pollen exposure risk range from 1 to 74% for trees considered to be highly allergenic in the same city. This variation results from differences in the pollen allergenicity datasets, which become more pronounced when a city's canopy is dominated by only a few species and genera. In an increasingly urbanized world, diverse urban forests offer a potentially safer strategy aimed at diluting sources of allergenic pollen until better allergenicity data is developed. Our findings highlight an urgent need for a science-based approach to guide public health and urban forest planning.

Temporal trends and sex differences in sudden cardiac death in the Copenhagen City Heart Study.

OBJECTIVE: More knowledge about the development of sudden cardiac death (SCD) in the general population is needed to develop meaningful predictors of SCD. Our aim with this study was to estimate the incidence of SCD in the general population and examine the temporal changes, demographics and clinical characteristics. METHODS: All participants in the Copenhagen City Heart Study were followed from 1993 to 2016. All death certificates, autopsy reports and national registry data were used to identify all cases of SCD. RESULTS: A total of 14 562 subjects were included in this study. There were 8394 deaths with all information available, whereof 1335 were categorised as SCD. The incidence of SCD decreased during the study period by 41% for persons aged 40-90 years, and the standardised incidence rates decreased from 504 per 100 000 person-years (95% CI 447 to 569) to 237 per 100 000 person-years (95% CI 195 to 289). The incidence rate ratio of SCD between men and women ≤75 years was 1.99 (95% CI 1.62 to 2.46). The proportion of SCD of all cardiac deaths decreased during the observation period and decreased with increasing age. Men had more cardiovascular comorbidities (OR 1.34, 95% CI 1.07 to 1.68, p<0. 01), and SCD was the first registered manifestation of cardiac disease in 50% of all cases. CONCLUSION: The incidence of SCD in the general population has declined significantly during the study period but should be further investigated for more recent variations as well as novel risk predictors for persons with low to medium risk of SCD.

Emergency department visits for pediatric traumatic injuries during general confinement: A single-center study in an urban setting.

BACKGROUND: The first case of SARS-CoV-2 was detected in France in January 2020 and the government decided on national confinement from March 17 to May 11, 2020. Our aim was to analyze the incidence of pediatric emergency department (ED) visits and hospitalizations for traumatic injuries during this period. METHODS: Any visit with an ICD-10 discharge diagnosis code of burn, fracture, traumatic wound, or sprain/bruise contusion was recorded within the 2 weeks before (weeks 10 and 11) and during the confinement (weeks 12 and 19). The visits with the same ICD-10 discharge diagnosis code during similar weeks of the previous 2 years were also included. For each of those visits, the number of hospitalizations was counted. RESULTS: The number of recorded visits between week 10 and 19 in 2018, 2019, and 2020 was, respectively, 2657, 2625, and 1106 children. The average number of visits per day during the confinement (13±5) was significantly different from the average number of visits per day during the same weeks in 2018 and 2019 (38±8 vs. 39±9, P<0.0001). The average number of visits per day was significantly lower during confinement compared with 2018/2019 for three categories of diagnoses (P<0.0001) but not for burns (1.7 vs. 1.8, P=0.23). The average number of hospitalizations per day was significantly lower during the confinement than during 2018/2019 (1.6±1.3 vs. 2.6±1.8, P<0.0001). CONCLUSION: Confining children in an urban setting appears to decrease the incidence of injuries, except for burns. These data may be useful in reorganizing caregiver supervision and hospital units. These results will need to be consolidated in a multicenter study.

Excess of cardiovascular deaths during the COVID-19 pandemic in Brazilian capital cities.

INTRODUCTION: During the COVID-19 pandemic, excess mortality has been reported, while hospitalisations for acute cardiovascular events reduced. Brazil is the second country with more deaths due to COVID-19. We aimed to evaluate excess cardiovascular mortality during COVID-19 pandemic in 6 Brazilian capital cities. METHODS: Using the Civil Registry public database, we evaluated total and cardiovascular excess deaths, further stratified in specified cardiovascular deaths (acute coronary syndromes and stroke) and unspecified cardiovascular deaths in the 6 Brazilian cities with greater number of COVID-19 deaths (São Paulo, Rio de Janeiro, Fortaleza, Recife, Belém, Manaus). We compared observed with expected deaths from epidemiological weeks 12-22 of 2020. We also compared the number of hospital and home deaths during the period. RESULTS: There were 65 449 deaths and 17 877 COVID-19 deaths in the studied period and cities for 2020. Cardiovascular mortality increased in most cities, with greater magnitude in the Northern capitals. However, while there was a reduction in specified cardiovascular deaths in the most cities, the Northern capitals showed an increase of these events. For unspecified cardiovascular deaths, there was a marked increase in all cities, which strongly correlated to the rise in home deaths (r=0.86, p=0.01). CONCLUSION: Excess cardiovascular mortality was greater in the less developed cities, possibly associated with healthcare collapse. Specified cardiovascular deaths decreased in the most developed cities, in parallel with an increase in unspecified cardiovascular and home deaths, presumably as a result of misdiagnosis. Conversely, specified cardiovascular deaths increased in cities with a healthcare collapse.

Epidemiological Investigation and Prevention Control Analysis of the Longitudinal Distribution of COVID-19 in Henan Province, China.

The objective was to analyze the longitudinal distribution, epidemiological characteristics, and local prevention and control measures of coronavirus disease 2019 (COVID-19) in six cities in Henan Province, China, from 21 January 2020 to 17 June 2020: Xinyang City (including Gushi County), Nanyang City (including Dengzhou City), Zhumadian City (including Xincai County), Zhengzhou City (including Gongyi City), Puyang City, and Anyang City (including Hua County). Data were collected and analyzed through the COVID-19 information published on the official websites of the health commissions in the six selected cities of Henan Province. As of 17 June 2020, the cumulative incidence rate of COVID-19 in Henan Province was 1.33/100,000, the cumulative cure rate was 98.27%, the cumulative mortality rate was 1.73%, the age range of diagnosed cases was 5 days to 85 years old, and the male-to-female ratio was 1.09:1. The confirmed cases of COVID-19 in Henan Province were mainly imported cases from Hubei, accounting for 87.74% of all cases, of which the highest proportion was 70.50% in Zhumadian. The contact cases and local cases increased in a fluctuating manner over time. In this paper, epidemiological characteristics of COVID-19 in Henan Province were analyzed from the onset of the outbreak to the effective control within 60 days, and effective and distinctive prevention and control measures in various cities were summarized to provide a favorable useful reference for the further formulation and implementation of epidemic prevention and control and a valuable theoretical basis for effectively avoiding a second outbreak.IMPORTANCE Epidemic prevention and control in China have entered a new stage of normalization. This article analyzes the epidemiological characteristics of COVID-19 in Henan Province and summarizes the effective disease prevention and control means and measures at the prefecture level; the normalized private data provide a theoretical reference for the formulation and conduct of future prevention and control work. At the same time, these epidemic prevention and control findings can also be used for reference in other countries and regions.

Infant Mortality in the Metropolitan Region, Chile 2005-2014. / Mortalidad Infantil en las comunas de la Región Metropolitana, periodo 2005-2014.

INTRODUCTION: Infant mortality depends on the economic, social, and cultural level of development of the place of residence. OBJECTIVE: To describe the infant mortality rates (IMR) and the late infant mortality rates (LIMR) of the Metropolitan Region (MR) communes and to evaluate their trend between 2005 and 2014. MATERIAL AND METHOD: Ecological study that describes the rates of the 52 communes of the MR. For the analysis, the IMR and LIMR were elaborated for each year and com mune and were compared using population attributable risk (PAR), attributable risk percent (AR%), and rate ratio (RR). Trends were analyzed through the Prais-Winsten model. A value p < 0.05 was considered a statistically significant trend. RESULTS: The commune 'Independencia' presented the hig hest IMR and LIMR with 12.7 and 4.05 per 1000 live births respectively, 1.75 and 2.05 times more compared with the IMR and LIMR of the MR. The commune 'Las Condes' and 'Vitacura' presented the lowest IMR and LIMR respectively. The IMR trend regarding 2005 increased in Lo Barnechea, Lo Espejo, and Recoleta, and decreased in Las Condes, Macul, Pudahuel and San Bernardo. The LIMR decreased in Peñalolén, Puente Alto, Las Condes, Providencia, San Bernardo, Macul, Pudahuel, Tala- gante, Pedro Aguirre Cerda, and Quilicura, and increased in Peñaflor. CONCLUSION: The regional IMR and LIMR hide the slight increase in rates and the persistence of heterogeneity among communes. This forces us to explore the causes of these inequities through future analytical studies.

Factors associated with 30-days and 180-days psychiatric readmissions: A snapshot of a metropolitan area.

Psychiatric re-hospitalization rate is a widely used quality indicator within mental health care. This study aims to investigate which variables are implied in determining readmissions over two intervals after the index event, 30 days and 6 months. The study sample included 798 inpatients, it was divided into two groups: not readmitted patients (NRP) and readmitted patients (RP), which has been further split into: Readmitted within 30 days (RP30dd) and Readmitted during the 150-day period (between 31 and 180 days) after the index discharge (RP150). A multivariate logistic regression with backward selection method was performed in order to find variables independently associated with readmission. The overall incidence of readmissions was 16.04%. Discharge to a Psychiatric Nursing Home was found to be a protective factor for all the groups. In adds, for the overall readmission, compulsory index admission and higher education (this lasts as in RP30dd group) were protective factors; whereas higher length of stay (as for readmission within 31-180 days) and a diagnosis of Personality Disorder were risk factors. The patient-specific factors significantly associated with likelihood of rehospitalization in the final model do identify some high-risk groups toward to whom possibly address prevention strategies.

Changes to cardiovascular risk factors over 7 years: a prospective cohort study of in situ urbanised residents in the Chaoyang District of Beijing.

OBJECTIVES: To examine changes in cardiovascular risk factors of in situ urbanised residents between 2010 and 2017. DESIGN: Population-based cohort study. SETTING: The Chaoyang District of Beijing, China. PARTICIPANTS: A total of 942 in situ urbanised rural residents aged 35-64 who participated in the cardiovascular disease (CVD) risk factors study in China between 2010 and 2017. MAIN OUTCOME MEASURES: Lifestyles (smoking, drinking and effective exercise) and medical history (diabetes, hypertension, dyslipidaemia, overweight and obesity) were self-reported. New cases of diabetes, hypertension, dyslipidaemia, overweight and obesity were confirmed by physical examination or blood biochemical tests. Multiple linear regression and log-binomial models analyses adjusted for sociodemographic confounders were conducted to evaluate any changes of clinical indexes and to estimate prevalence rate ratios (PRRs), respectively. RESULTS: During the study period of 2010-2017, diastolic blood pressure elevated by 3.55 mm Hg, central blood pressure increased by 4.39 mm Hg, total cholesterol decreased by 0.29 mmol/L and hypertension increased significantly (PRR=1.25, p<0.05) after adjusting for demographic, lifestyle and family history factors. Effective exercise rate (PRR=1.57), prevalence of diabetes (PRR=1.36) and dyslipidaemia (PRR=1.19) all increased from 2010 to 2017. However, these changes were not significant after adjusting for confounders (p>0.05). Prevalence of smoking, drinking, hypertension, overweight and obesity was significantly higher in males than females in both 2010 and 2017. In 2017, the 10-year risk of atherosclerotic CVD increased in 29.8% of participants and decreased in 6.1% of individuals. CONCLUSIONS: CVD risk factors augmented remarkably for in situ urbanised rural residents aged 35-64 in the Chaoyang District of Beijing, especially those indicators related to blood pressure. Awareness of the direction and magnitude of these risk factor changes may be beneficial in informing targeted strategies for preventing CVDs of in situ urbanised populations.

Mortalidad Infantil en las comunas de la Región Metropolitana, periodo 2005-2014 / Infant Mortality in the Metropolitan Region, Chile 2005-2014

Resumen: Introducción: La mortalidad infantil depende del nivel de desarrollo económico, social y cultural del área de residencia. Objetivo: Describir las tasas de mortalidad infantil (TMI) y mortalidad infantil tardía (TMIT) de las comunas de la Región Metropolitana (RM) y evaluar su tendencia en el perio do 2005-2014. Material y Método: Estudio ecológico que describe las tasas en las 52 comunas de la Región Metropolitana (RM). Para el análisis se construyó la TMI y TMIT para cada año y comuna y se compararon mediante riesgo atribuible poblacional (RAP), Riesgo atribuible porcentual (RAP%) y razón de tasas (RT). Las tendencias se evaluaron con el modelo Prais-Winsten. Se consideró una tendencia estadísticamente significativa un valor p < 0,05. Resultados: La comuna de Independencia mostró la TMI y TMIT más altas con 12,7 y 4,05 por mil RNV respectivamente; 1,75 y 2,05 veces comparado con la TMI y TMIT de la RM. Las tasas más bajas se observaron en Las Condes (TMI) y en Vitacura (TMIT). La tendencia de la TMI respecto al 2005 aumentó en Lo Barnechea, Lo Espejo y Recoleta y disminuyó en Las Condes, Macul, Pudahuel y San Bernardo. La TMIT disminuyó en Peñalolén, Puente Alto, Las Condes, Providencia, San Bernardo, Macul, Pudahuel, Talagante, Pedro Aguirre Cerda y Quilicura y aumentó en Peñaflor. Conclusión: La TMI y la TMIT regional ocultan el leve incremento de las tasas y la persistencia de la heterogeneidad entre las comunas, lo que obliga a explorar las causas de estas inequidades en estudios analíticos a futuro.

Abstract: Introduction: Infant mortality depends on the economic, social, and cultural level of development of the place of residence. Objective: To describe the infant mortality rates (IMR) and the late infant mortality rates (LIMR) of the Metropolitan Region (MR) communes and to evaluate their trend between 2005 and 2014. Material and Method: Ecological study that describes the rates of the 52 communes of the MR. For the analysis, the IMR and LIMR were elaborated for each year and com mune and were compared using population attributable risk (PAR), attributable risk percent (AR%), and rate ratio (RR). Trends were analyzed through the Prais-Winsten model. A value p < 0.05 was considered a statistically significant trend. Results: The commune 'Independencia' presented the hig hest IMR and LIMR with 12.7 and 4.05 per 1000 live births respectively, 1.75 and 2.05 times more compared with the IMR and LIMR of the MR. The commune 'Las Condes' and 'Vitacura' presented the lowest IMR and LIMR respectively. The IMR trend regarding 2005 increased in Lo Barnechea, Lo Espejo, and Recoleta, and decreased in Las Condes, Macul, Pudahuel and San Bernardo. The LIMR decreased in Peñalolén, Puente Alto, Las Condes, Providencia, San Bernardo, Macul, Pudahuel, Tala- gante, Pedro Aguirre Cerda, and Quilicura, and increased in Peñaflor. Conclusion: The regional IMR and LIMR hide the slight increase in rates and the persistence of heterogeneity among communes. This forces us to explore the causes of these inequities through future analytical studies.

Effect of the recent economic crisis on socioeconomic inequalities in mortality in nine urban areas in Europe.

OBJECTIVE: To analyse socioeconomic inequalities in all-cause mortality among men and women in nine European urban areas during the recent economic crisis, and to compare the results to those from two periods before the crisis. METHOD: This is an ecological study of trends based on three time periods (2000-2003, 2004-2008 and 2009-2014). The units of analysis were the small areas of nine European urban areas. We used a composite deprivation index as a socioeconomic indicator, along with other single indicators. As a mortality indicator, we used the smoothed standardized mortality ratio, calculated using the hierarchical Bayesian model proposed by Besag, York and Mollié. To analyse the evolution of socioeconomic inequalities, we fitted an ecological regression model that included the socioeconomic indicator, the period of time, and the interaction between these terms. RESULTS: We observed significant inequalities in mortality among men for almost all the socioeconomic indicators, periods, and urban areas studied. However, no significant changes occurred during the period of the economic crisis. While inequalities among women were less common, there was a statistically significant increase in inequality during the crisis period in terms of unemployment and the deprivation index in Prague and Stockholm, respectively. CONCLUSIONS: Future analyses should also consider time-lag in the effect of crises on mortality and specific causes of death, and differential effects between genders.

Ellisras Longitudinal Study 2017: patterns of physical activity in an urban and rural setting among black South African adults (ELS 23).

BACKGROUND: Understanding patterns of physical activity among adults can lead to targeted approaches to improve activity levels in the African population. This study aimed to determine whether age, gender, location and employment status could predict physical activity among rural and urban South African adults, and to determine the participants' risk of developing cardiovascular disease (CVD). METHODS: A cross-sectional design was conducted on 319 participants of mean age 57 ± 10.43 years. Participants were sampled using a stratified random-sampling procedure from an urban township in Langa, Western Cape Province, and a rural township in Mt Frere, Eastern Cape Province, South Africa. A researcher-generated questionnaire was used to collect sociodemographic and physical activity data. Linear regression analysis was used to test predictive relationships. RESULTS: Gender and geographical location were significant predictors (p = 0.001) of physical activity. Rural participants engaged more in physical activity (91.5%) than urban participants (84.2%) and were more likely to meet the physical activity recommendations to promote cardiovascular fitness (p = 0.000). The most frequent physical activities in rural participants were walking (15.4%), household chores (18.8%) and household chores + gardening (15.4%). The most frequent physical activities in urban participants were household chores (34.2%), and household chores + walking (33.7%). In terms of duration of physical activity, rural participants spent longer periods engaging in activities lasting up to two hours (21.4%), compared to 5.9% in urban participants (p = 0.000). CONCLUSIONS: Gender and geographical location were significant predictors of physical activity among black South African adults. Overall, rural adults engaged in more physical activity than urban-dwelling adults. Males also engaged in more physical activity and at a higher intensity than females. Most rural participants met the American College of Sports Medicine recommendations for cardiovascular fitness and therefore were at minimal risk for developing CVD compared to their urban counterparts.

Time Trends in First-Episode Genital Herpes Simplex Virus Infections in an Urban Sexually Transmitted Disease Clinic.

BACKGROUND: Genital herpes simplex virus type 1 (HSV-1) has emerged as the leading cause of first-episode genital herpes among specific populations in the United States, such as adolescents, young adult women, and men who have sex with men (MSM). We examined trends in the etiology of first-episode genital herpes diagnoses over time in a sexually transmitted disease (STD) clinic population. METHODS: Using an electronic database, we identified persons diagnosed as having first-episode genital herpes at Public Health - Seattle & King County STD Clinic from 1993 to 2014 and compared risk factors for genital HSV-1 versus herpes simplex virus type 2 (HSV-2) infection. RESULTS: Of 52,030 patients with genital ulcers, 3065 (6.15%) had first-episode genital herpes infection: 1022 (33.3%) with HSV-1 and 2043 (67.7%) with HSV-2. Overall, 1154 (37.7%) were women, the median age was 28 years (interquartile range, 24-36 years), 1875 (61.2%) patients were white, and 353 (11.5%) were MSM. The number of patients diagnosed as having first-episode genital HSV-2 declined on average by 5.5 persons per year, from 208 in 1993 to 35 in 2014 (change of -5.6 per year; 95% confidence interval [CI], -6.9 to -4.1), whereas HSV-1 diagnoses remained stable at approximately 50 per year (change of 0.2; 95% CI, -0.4 to 0.9). In a multivariate model, persons diagnosed as having first-episode genital HSV-1 rather than genital HSV-2 infection were more likely to be younger (age <30 years [relative risk {RR}, 1.38; 95% CI, 1.22-1.55]), white (RR, 3.16; 95% CI, 2.57-3.88), and MSM (RR, 1.50; 95% CI, 1.31-1.71). CONCLUSIONS: We observed a significant decrease in the frequency of first-episode genital HSV-2 and a stable number of first-episode genital HSV-1 infections in a STD clinic over the last 2 decades.

Urban environment and psychiatric disorders: a review of the neuroscience and biology.

Most of the world's population now lives in cities. While living in cities have both health risks and benefits, mental health has been usually considered to be negatively affected by urbanicity. While mental health disorders have complex etiology and multiple causes, it has been shown in multiple observational studies that mood and anxiety disorders are more prevalent in urban centers and incidence has been increasing. In addition, the incidence of schizophrenia is strongly increased in people born and raised in cities. Studies on the effects of urbanicity on the brain, however, are more challenging to conduct, since individual and environmental factors are hard to distinguish. The main objective of this article is to review studies on how specific neural processes mediate those associations between urbanicity and psychiatric disorders and how environmental factors affect genetic regulation (epigenetics). Neuroimaging studies have shown how urban stressors might affect the brain by conducting experiments using functional magnetic resonance imaging (fMRI). There have been demonstrations that urban upbringing and city living have dissociable impacts on social evaluative stress processing in humans. City living was associated with increased amygdala activity and the urban upbringing has been shown to affect the perigenual anterior cingulate cortex, a key region for regulation of amygdala activity, negative affect and stress. In addition, studies on epigenetics have shown associations between exposure to features of the environment and methylation patterns. The goal of understanding how urban environments act as a risk factor for mental disorders may be pursued on several levels. It can be approached by measuring the effects of economic factors (unemployment, socioeconomic status), social condition (social network support), environmental exposures (toxins, air pollution, noise, light), that must be weighed to identify how it contributes to mental disorders.

Neighborhood social and economic change and diabetes incidence: The HeartHealthyHoods study.

We studied the association between neighborhood social and economic change and type 2 diabetes incidence in the city of Madrid (Spain). We followed 199,621 individuals living in 393 census tracts for diabetes incidence for 6 years using electronic health records, starting in 2009. We measured neighborhood social and economic change from 2005 to 2009 using a finite mixture model with 16 indicators that resulted in four types of neighborhood change. Adjusted results showed an association between neighborhood change and diabetes incidence: compared to those living in Aging/Stable areas, people living in Declining SES, New Housing and Improving SES areas have an 8% (HR = 0.92, 95% CI 0.87 to 0.99), 9% (HR = 0.91, 95% CI 0.81 to 1.01) and 11% (HR = 0.89, 95% CI 0.81 to 0.98) decrease in diabetes incidence. This evidence can help guide policies for diabetes prevention by focusing efforts on specific urban areas.

The Urban Liveability Index: developing a policy-relevant urban liveability composite measure and evaluating associations with transport mode choice.

BACKGROUND: Designing healthy, liveable cities is a global priority. Current liveability indices are aggregated at the city-level, do not reflect spatial variation within cities, and are often not aligned to policy or health. OBJECTIVES: To combine policy-relevant liveability indicators associated with health into a spatial Urban Liveability Index (ULI) and examine its association with adult travel behaviours. METHODS: We developed methods to calculate spatial liveability indicators and the ULI for all residential addresses in Melbourne, Australia. Associations between the address-level ULI and adult travel behaviours from the 2012-2014 Victorian Integrated Survey of Travel and Activity (VISTA) (n = 12,323) were analysed using multilevel logistic regression. Sensitivity analyses to evaluate impact of methodological choices on distribution of liveability as assessed by the ULI and associations with travel mode choice were also conducted. RESULTS: Liveability estimates were calculated for 1,550,641 residential addresses. ULI scores were positively associated with active transport behaviour: for each unit increase in the ULI score the estimated adjusted odds ratio (OR) for: walking increased by 12% (95% Credible Interval: 9%, 15%); cycling increased by 10% (4%, 17%); public transport increased by 15% (11%, 19%); and private vehicle transport decreased by 12% (- 9%, - 15%). CONCLUSIONS: The ULI provides an evidence-informed and policy-relevant measure of urban liveability, that is significantly and approximately linearly associated with adult travel behaviours in the Melbourne context. The ULI can be used to evaluate progress towards implementing policies designed to achieve more liveable cities, identify spatial inequities, and examine relationships with health and wellbeing.