Evaluating the Impact of City-wide Collaborations in the Reduction of Racial Disparities in Breast Cancer Mortality

Background:Racial disparities in breast cancer mortality are well documented in Chicago. Over the past seven years, research has identified key drivers of the disparity and numerous interventions have been implemented to reduce excess morbidity and mortality for black women. The aim of this study is to extend previous trend analysis based on newly available data to evaluate the efficacy of collective interventions across the Chicagoland area.

Methods:Vital records data was utilized to calculate 3-year interval age-adjusted breast cancer mortality rates for non-Hispanic Black and non-Hispanic White women in Chicago, New York, Los Angeles, Houston, Philadelphia and the United States from 1999 – 2010. The disparity in breast cancer mortality was measured based on race specific rate ratios. SAS 9.2 was used for data analysis.

Results: Findings reveal a 35% reduction in the disparity in Chicago starting in the 2008 - 2010 interval compared to 2005-2007. In the later interval, Chicago and the US have contrasting trends despite consistent levels of the disparity, 40%.The disparity trend increases across the study period for the US, Los Angeles, Houston and Philadelphia. Despite increasing trends, breast cancer mortality rates are declining for both black and white women in all locales except Chicago. In the later interval, Chicago mortality rates for black women decreased compared to a slight increase for white women.

Conclusion:For the first time improvements in breast cancer survival has been demonstrated for black women in Chicago. Increasing disparities in metropolitan areas comparable to Chicago suggests that this is not a secular trend. Preliminary data indicates collaborative efforts in Chicago have contributed to these findings. Further analysis is needed to understand the race-specific trends in breast cancer survival.