Disparity in breast cancer mortality by age and geography in 10 racially diverse US cities.

OBJECTIVES: Assess geographic variation in breast cancer racial mortality disparity by age cohorts in US and ten cities with large African American populations. METHODS: Non-Hispanic Black (NHB) and Non-Hispanic White (NHW) female breast cancer mortality rates and NHB:NHW rate ratio (RR) (disparity) were calculated by four age group categories: <40, 40-49, 50-64 and 65+ with time period 1999-2013. RESULTS: In all 10 cities and the US, the most pronounced breast cancer disparities, measured by RR, were seen among younger women. In age group <40, the RR ranges from 1.71 in Houston to 5.37 in Washington, DC. For age group 50-64, the disparity was less pronounced, ranging from 1.24 in New York to 1.72 in Chicago. For 65+ age group, there was wide city to city variation in breast cancer mortality disparity. Three cities had higher mortality for NHW compared to NHB; Baltimore 0.78, Washington DC 0.94 and New York 0.98. One city had no statistically significant racial variation in breast cancer mortality in this age group and six cities had increased NHB: NHW mortality disparities. CONCLUSIONS: While the mortality rate for breast cancer is lower among younger women, the NHB:NHW disparities, as measured by rate ratios, are most pronounced in these age groups. Given the absence of available data regarding incidence, stage and subtypes, further research is necessary and such research is important, given the possible policy implications of these results with respect to screening guidelines and coverage for mammography and breast cancer treatment in particular for younger NHB women.

Changes in the racial disparity in breast cancer mortality in the ten US cities with the largest African American populations from 1999 to 2013: The reduction in breast cancer mortality disparity in Chicago.

PURPOSE: Assess progress made to reduce racial disparity in breast cancer mortality in Chicago compared to nine other cities with largest African American populations and the US. METHODS: The Non-Hispanic Black (NHB) and Non-Hispanic White (NHW) female breast cancer mortality rates and rate ratios (RR) (disparity) were compared between 1999 and 2005 and 2006 and 2013. RESULTS: Between the two periods, the NHB breast cancer mortality rate in Chicago decreased by 13.9% (95% CI [-13.81, -13.92] compared to 7.7% (95% CI [-7.52, -7.83]) for NHW. A drop of 20% in the disparity was observed, from 51% (RR: 1.51, 95% CI [-7.52, -7.83]) to 41% (RR: 1.41, 95% CI [1.30, 1.52]). Whereas from 1999 to 2005 Chicago's disparity was above that of the U.S., from 2006 to 2013, it is now slightly lower. For the remaining nine cities and the US, the mortality disparity either grew or remained the same. CONCLUSIONS: Chicago's improvement in NHB breast cancer mortality and disparity reduction occurred in the context of city-wide comprehensive public health initiatives and shows promise as a model for other cities with high health outcome disparities.