Purpose: Black women are more likely to develop breast cancer at earlier ages and experience increased morbidity and mortality from breast cancer. Our purpose was to use nationally representative breast cancer mortality data to characterize breast cancer mortality disparities by age category to inform precision cancer prevention strategies.
Materials and Methods: We used publicly available mortality data from the CDC WONDER database from 1999 to 2020. Detailed mortality data are compiled from data provided by the 57 vital statistics jurisdictions through the National Vital Statistics System. Data are based on death certificates for U.S. residents, which identifies a single underlying cause of death and demographic data. Breast cancer deaths were identified using ICD-10 diagnosis codes (C50). Crude death rate was breast cancer deaths by the population size per 100,000 people. Breast cancer mortality disparities were assessed by calculating Black:White mortality rate ratios for 5 year age categories for 25 to 84 year old females, stratified by geographic region.
Results: Among women between the ages of 40 – 74 years old, Black women had a crude mortality rate of 53.7 compared with 38.7 in White women (rate ratio 1.39). For both Black and White women, crude breast cancer mortality rates increased by age category. Overall, breast cancer mortality disparities as measured by rate ratios, were highest for the youngest age categories (2.50 in women between the ages of 25-29 years old) and decreased with progressive age categories (1.15 in women between the ages of 80-84 years old) (Figure 1). For 35-39 year old women, rate ratios ranged from 1.59 (Northeast), to 2.06 (South). For 40-49 year old women, rate ratios ranged from 1.58 (Northeast) to 1.88 (South). For 50-59 year old women, rate ratios ranged from 1.42 (Northeast) to 1.69 (Midwest). For women between the ages of 60-69, rate ratios ranged from 1.22 (Northeast) to 1.40 (Midwest). For women between the ages of 70-74, rate ratios ranged from 1.09 (Northeast) to 1.29 (Midwest).
Conclusion: Breast cancer mortality disparities, as measured by rate ratios, are the highest for younger age categories. For both Black and White women, crude breast cancer mortality rates increased by age category.
Clinical Relevance Statement: Health care practitioners and policy makers should consider targeted outreach efforts to increase mammography screening percentages and increase access to evidence-based high risk screening studies among eligible Black women in younger age categories to reduce breast cancer mortality disparities.
