Characterizing physical activity and food urban environments: a GIS-based multicomponent proposal

BACKGROUND: Healthier urban environments influence the distribution of cardiovascular risk factors. Our aim was to design and implement a multicomponent method based on Geographic Information Systems to characterize and evaluate environmental correlates of obesity: the food and the physical activity urban environments. METHODS: Study location comprised a socio-demographically average urban area of 12 contiguous census sections (≈16,000 residents), in Madrid, Spain. We conducted on-field audits on all food stores and street segments. We designed a synthetic index integrating continuous measures of both environments, by kernel density analyses. Index ranges from 0 to 100 (least-most healthy). RESULTS: We found a heterogeneous distribution with 75 and 50 % of the area scoring less than 36.8 and 25.5, respectively. Census sections of study area were categorized by Jenks intervals as high, medium-high, medium-low and low. 41.0 % of residents lived in an area with a low score, 23.6 % medium-low and 31.1 % medium-high and 4.2 % in a high. CONCLUSION: The proposed synthetic index may be a relevant tool to inform urban health interventions, providing a feasible way to integrate different measures of barriers and facilitators of healthy urban environments in terms of food and physical activity.This study was supported by the European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC Starting Grant HeartHealthyHoods Agreement n. 336893. Usama Bilal was supported by a fellowship from the Obra Social La Caixa and by a Johns Hopkins Center for a Livable Future-Lerner FellowshipS