The relationship between built environment and health in the Lisbon Metropolitan area – can walkability explain diabetes’ hospital admissions?

Abstract

IntroductionType 2 diabetes is one of the non-communicable diseases with higher increasing incidence across the world. Portugal is one of the most affected countries with this increase. Most risk factors for diabetes are modifiable and can be changed by a supportive built environment. The walkability index has been wildly used as concept to describe a healthy built environment. However, the ecological view of health and diabetes identifies the necessity of a multilevel intervention to the creation of a supportive built environment.The goal of this paper is to evaluate the association between walkability indicators and hospital admissions due to diabetes, in the Lisbon Metropolitan Area, by different methods through a proposed ecological model. MethodsThe built environment characteristics were evaluated using walkability measures including density, diversity and design, but also air quality and green areas availability. The socio-economic characteristic was controlled by the most common indicators, but it also included house size and house cost. The diabetes incidence was measured by hospital admissions due to diabetes. The statistical analysis was performed by a path analysis model that allows to consider the complexity of several effects on diabetes. ResultsThe results show that built environment influences diabetes through air pollution and active travel. The proposed conceptual model explains 27% of the variance of hospital admissions due to diabetes. Additionally, the mediating variables active travel and air pollution had the variance explained in 73% and 70% respectively. ConclusionsThe results stress the non-direct influence of the built environment in health, showing that health can be improved through the promotion of active travel and the improvement of air quality. The improvement of these aspects is relevant at different levels of intervention, revealing the importance of the civil parishes level. The results reinforce the importance of policies at different levels to effectively change behaviour.