Espaços verdes e mortalidade por doenças cardiovasculares no município do Rio de Janeiro.

Abstract

Many studies in Epidemiology has investigated urban environment influency on people's health. Green areas' benefits has been one of the aspects studied recently. One of the main pointed out ways is the promotion of physical exercises practicing. Other benefits would include improvement of psychosocial conditions and air quality. These factors, on the other hand, have been associated with cardiovascular health. In that sense, this work aims to investigate the association between green areas and mortality from ischemic heart diseases and cerebrovascular diseases in Rio de Janeiro, from 2010 to 2012. An ecological study has been made, having census tracts as analysis unit. As the outcome variable, it was calculated the standardized mortality ratio per sex and age, using the indirect method. The exposure to green areas was measured through the mean and the variability of the Normalized Difference Vegetation Index (NDVI) during the studied period, in a 100 m buffers around the census tract. Data were analysed using a Linear Conditional Autrorregressive Model, which considers also the spatial dependence structure. The model was adjusted considering the covariates: Social Development Index; vehicular traffic density, divided in collector and local roads and primary, secondary and structural ways, all used as pollution proxy; and census coastal sector's marker. Once the sample was adjusted controlling possible confusing factors, it was verified a 4.5% mortality reduction (IC95%: 7.3%, 1.6%) in areas where exposition reached the highest interquartile range on NDVI; and a 3.4% reduction (CI95%: 6.2%, 0.7%) in areas related to the highest interquartile range on variability, both in comparison with the lowest interquartile range. This result indicates an inverse association between exposure to green areas and mortality by ischemic heart diseases and cerebrovascular diseases in Rio de Janeiro. Furthermore, mortality increase is associated to worse living conditions and air pollution.