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.