Urban environments and their impact on population health Dr Daniela Fecht UK Small Area Health Statistics Unit MRC-PHE Centre for Environment and Health Imperial College London

Historic background  Health status in urban areas historically lower compared with rural areas, e.g. higher mortality rates from infectious diseases

Historic background  Health status in urban areas historically lower compared with rural areas, e.g. higher mortality rates from infectious diseases  Industrialisation in 19 th century accounted for poorer health in urban areas e.g. higher infant mortality, shorter life span

Historic background  Sanitary awakening in the late 19 th century led to significantly improved health status for urban residents

The situation today  Differences is health status between urban and rural areas still persist today  Not all are due to socio-economic differences Kyte L, Wells C Variations in life expectancy between rural and urban areas of England, Health Statistics Quarterly 46. Office for National Statistics. Index of Multiple Deprivation 2007

Why focus on urban areas? Source: Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat, World Population Prospects: The 2011 Revision. Main challenges facing urban areas:  Obesity epidemic  Climate change

Factors influencing urban health

Demographic factors The Marmot Review 2012: Fair Society, Healthy Lives.  Age & sex  Ethnicity  Education  Occupation  Socio-economic status Life expectancy Disability-free life expectancy Pension age increase

Lifestyle choices  Diet  Smoking  Drinking habits  Substance abuse  Physical activity Health Survey for England, 2009 Prevalence of obesity among adults, by gender, 1993 to % 5% 10% 15% 20% 25% 30% menwomen

Social environment  Social support network  Neighbourhood cohesion  Crime  Socio-economic status  Number of hospitals and special care units Social environ- ment Health care provision

Environmental exposure  Air pollution (indoor & outdoor)  Noise pollution (indoor & outdoor)  Water contamination  Electromagnetic fields Social environ- ment Health care provision Environ- mental exposure

Urban structure  Land cover mix  Transport network  Street layout  Population density Social environ- ment Health care provision Environ- mental exposure Urban structure

Physical features  Topography  Geology  Meteorology  Hydrology Social environ- ment Health care provision Environ- mental exposure Physical features Urban structure

Factors influencing urban health

Can we detect any associations between urban form and mortality rates in cities in Great Britain? Research question Study aims:  To create measures to quantify the probable influence of population distribution, land cover, transport network and geographical characteristics (e.g. location, terrain) on human health,  To select relevant health outcomes that are potentially influenced by urban form,  To investigate whether physical features within a city and the urban structure are factors that influence the health of the urban population. Fecht D, Fortunato L, Morley D, Hansell A, Gulliver J Associations between urban metrics and mortality rates in England. Environmental Health. In press.

Study design  Units of analysis: City level All cities in England with > 100,000 residents (N=50)  Urban metrics: Computation of urban metrics for each city  Health outcomes: All death and cause-specific mortality ( ): Cardiovascular disease (CVD: heard disease, stroke) Road traffic accidents Separate analysis for men and women All ages and premature mortality (< 65 years olds)  Confounders: Socio-economic status: Income domain from IMD 2004 (city level) Smoking: using lung cancer mortality as proxy Air pollution: PM 10 (µg/m 3 ) concentrations, city average

ThemeUrban characteristic Urban metricsPotential health related benefitsPotential health related concerns PopulationPopulation density Population density (pop/km 2 ) city average  easy to walk/cycle  increase of physical activity  spread of infectious diseases  elevated air pollution levels  potential loss of green space  social stress Road network Walkability of cities Minor road density (km/km 2 )  easy to walk/cycle  increase of physical activity  elevated pollution levels  higher road-traffic noise levels Connectivity of road network Junction density (N/km 2 ): number of junctions over city area (km 2 )  easy to walk/cycle  increase of physical activity  elevated air pollution levels  higher road-traffic noise levels  increased number of road traffic accidents Urban sprawlPopulation within 100m of major roads (%)  higher noise and air pollution exposure across city population  less likely to walk/cycle and reduction in physical activity  increased number of road traffic accidents related to higher speed Land coverLand cover mix  easy to walk/cycle  increase of physical activity  less car usage  lower air pollution levels  residential areas potentially close to polluted areas Urban metrics

Descriptive results Premature mortality (<65 years) for men in England Socioeconomic status (tertiles) most affluent most deprived

Cardiovascular mortalityTraffic accident mortality Urban metricsWomen 0 – 65 yrsMen 0 – 65 yrsWomen 0 – 65 yrsMen 0 – 65 yrs Population density Low1.00 Medium1.04 (0.99 – 1.09)1.04 (1.01 – 1.07)*0.90 (0.73 – 1.11)0.91 (0.82 – 1.00) High1.13 (1.07 – 1.18)*1.10 (1.06 – 1.13)*0.75 (0.60 – 0.93)*0.77 (0.70 – 0.85)* Minor road density Low1.00 Medium1.05 (0.99 – 1.11)1.05 (1.01 – 1.09)*0.83 (0.66 – 1.05)0.87 (0.78 – 0.97)* High1.10 (105 – 1.16)*1.09 (1.06 – 1.13)*0.75 (0.60 – 0.93)*0.71 (0.64 – 0.78)* Junction densityLow1.00 Medium1.12 (1.07 – 1.18)*1.09 (1.06 – 1.12)*0.93 (0.72 – 1.15)0.99 (0.89 – 1.10) High1.16 (1.10 – 1.22)*1.12 (1.09 – 1.16)*0.90 (0.72 – 1.13)0.81 (0.73 – 0.91)* Population next to main roads Low1.00 Medium1.01 (0.96 – 1.06)0.98 (0.95 – 1.01)0.68 (0.55 – 0.85)*0.98 (0.89 – 1.09) High1.04 (0.99 – 1.09)1.04 (1.01 – 1.07)*0.87 (0.72 – 1.05)0.86 (0.78 – 0.95)* Shannon’s Diversity Index Low1.00 Medium0.97 (0.93 – 1.01)1.02 (0.99 – 1.04)1.13 (0.93 – 1.40)1.09 (1.00 – 1.19)* High0.95 (0.91 – 1.00)0.97 (0.94 – 1.00)1.39 (1.12 – 1.73)*1.22 (1.10 – 1.35)* * p < 0.05 Models account for age, socio-economic deprivation and smoking Risk of premature mortality

Conclusions  We found an association between transport patterns and population density and risk of premature mortality but only weak associations with land cover patterns.  We have seen a similar increase in the risk of all deaths and CVD mortality with increasing population, minor road and junction density whilst the risk of death from traffic accidents decreased.  Associations between urban form and mortality observed in this study suggest that characteristics of city structure might have negative effects on the overall health of urban communities.  Future urban planning and regeneration strategies can benefit from such knowledge to promote a healthy living environment for an increasing urban population.

Acknowledgements The work of the UK Small Area Health Statistics Unit is funded by Public Health England as part of the MRC-PHE Centre for Environment and Health, funded also by the UK Medical Research Council. The mortality and population data were supplied by the ONS, derived from the national mortality registrations and the Census.