[Availability of Urban Green Spaces and the Incidence of Breast Cancer at the Community Level in Chile: An Ecological Study].

Breast cancer is the most frequent and the main cause of death from cancer in women, which has been associated with biological, genetic, and socio-environmental factors. Living in urban green spaces has been widely related to health benefits.

Aim: To explore the association between exposure to urban green spaces and the incidence of breast cancer in Chile in an ecological design at the community level.

Methods: As exposure to green spaces, the following metrics were used separately: meeting the standard of green areas (10 m2/Inh), the Normalized Difference Vegetation Index (NDVI), the distance to the census block, and the quality index for squares and parks. The association was evaluated with the incidence ratio [IRR] and confidence interval (95% CI)] using negative binomial regression models adjusting for sociodemographic covariates.

Results: We found a significant negative statistical association of breast cancer with green areas [IRR (95%): 0.84 (0.70-0.95)] and a positive association with high NDVI [IRR (95%CI): 1.27 (1.04-1.55)] was positively associated. A moderate NDVI, the distance to the census block, and the quality index to public squares and parks were not associated with the disease.

Conclusions: Complying with the green area standard at the community level would be a protective factor for the CaM. In contrast, the NDVI vegetation index was associated with a higher risk. To assess the health impact of urban green spaces, more detailed measurements are required that can more accurately characterize exposure spatially and temporally, as well as individual-level analytical epidemiological studies.