Abstract C090: Associations between neighborhood green space and breast cancer outcomes among Philadelphia neighborhoods
Authors: Keating Benjamin C. , Lombardo Joseph , Zeigler-Johnson Charnita , DesJarlais Alex M. , Micua Taylor , Simone Nicole L. , McIntire Russell K. 
Published: January 2023

Access to green space has been shown to be associated with decreased incidence of cancer. The goal of this study is to identify associations between neighborhood green space indicators and breast cancer outcomes at the neighborhood level in Philadelphia.

Green space indicators were sourced from the National Land Cover Database (2006-2016), VT Spatial Analysis Lab (2008-2013) and Philadelphia Parks and Recreation (2016), and included average percent tree cover, average tree canopy, average low vegetation, count of public parks, and percent vacant lots. Breast cancer data from the PA Cancer Registry (2005-2014) included standardized incidence ratio (SIR), standardized mortality ratio (SMR), and mean aggressiveness (MA) of cancer. Neighborhood-level covariates were gathered from U.S. Census (American Communities Survey, 2008-2012) and the Public Health Management Corporation’s Household Health Survey (2012) for Philadelphia neighborhoods.

Pearson correlations were calculated to identify associations between environmental and green space indicators and breast cancer outcomes. Multivariable linear regression was used to identify if significant relationships persisted in the presence of demographic and socioeconomic disparities at the neighborhood level. Significance was determined at p-values &lt; 0.05.

SIR was significantly correlated with % of vacant lots (r=-.186), % of tree canopy cover within 50 meters from neighborhood centroid (r=.139) and the number of public parks (r=.125) per neighborhood. SMR was significantly correlated with vacant lots (r=.184) and tree canopy cover (r=-.104). MA was significantly correlated with tree canopy (r=-.124), tree canopy within fifty meters of neighborhood centroid (r=-.146), number of public parks (r=-.141), and % of vacant lots (r=.157). After controlling for covariates in multivariable linear regression models, the significant relationships between neighborhood green space indicators and breast cancer outcomes were no longer significant.

For SIR, the significant associations with green space indicators suggest that Philadelphia neighborhoods with a higher incidence of breast cancer have more green space and a lower % of vacant lots. For SMR and MA, associations suggest that neighborhoods with higher breast cancer mortality and aggressiveness have less green space and a higher % of vacant lots. The direction of these relationships makes sense, given the % and quality of neighborhood green space correlate closely with indicators of socioeconomic status. The lack of significance when controlling for confounders likely represents the limitations of using neighborhood-level data, rather than patient-level data, to measure the impact of green space on breast cancer outcomes. Future studies should identify green space exposure indicators at the individual level in order to more accurately identify the impact of urban green space on breast cancer outcomes. These data could inform city planning to decrease the burden of breast cancer among vulnerable populations.

Citation Format: Benjamin C. Keating, Joseph Lombardo, Charnita Zeigler-Johnson, Alex M. DesJarlais, Taylor Micua, Nicole L. Simone, Russell K. McIntire. Associations between neighborhood green space and breast cancer outcomes among Philadelphia neighborhoods [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C090.