Why do postmenopausal African-American women not benefit from overall breast cancer mortality decline?

BACKGROUND: An overall decline in U.S. female breast cancer mortality in the 1990s has been reported. However, several studies have shown that mortality trends are different for White women and African-American (AA) women. The purpose of this study was to assess differences in time trends and patterns of female breast cancer mortality among women by race and age in Ohio. MATERIAL AND METHODS: Joinpoint regression (JR) and age-period-cohort (APC) approaches were used to evaluate temporal changes in mortality and to assess period and birth generation impacts on observed patterns. Logistic regression was used to assess racial differences in tumor staging and grading among women diagnosed with breast cancer in Ohio from 1996 to 2000. Mortality data were obtained from NCHS (National Center for Health Statistics) via Surveillance Research Program, National Cancer Institute SEER*Stat software; Ohio incidence data were provided by the Ohio Cancer Incidence Surveillance System. RESULTS: Among women aged 30-74, a significant decline of 2.8% was noted since 1988 for White women. AA women in this age group have experienced significant decline (by 0.9%) since 1983. White women aged 30-39 years experienced a decline in mortality of 3.5% per year in the period 1986-2001, while decline by 2.3% was observed among Black women of that age since 1984. Among the age categories 40-49, 50-59, and 60-74, a decline in mortality rates was observed among White women in the 1990s. The decline was observed also among AA women aged 40-49, beginning in the mid 1980s, but not in the older AA age groups. Specifically, in AA women 60-74 and 75+, a mortality increase was observed within the entire study period (0.9% and 1.4%, respectively). CONCLUSIONS: Analysis of the data for Ohio suggests that AA women do not equally benefit from the overall decline in breast cancer mortality that is often sited. This is especially true for AA postmenopausal women who continue to experience an increase in breast cancer mortality. In light of existing literature and this analysis of data from the state of Ohio, we conclude that the reason for these differences lies mostly in disparities in access to care, as well as in differences in stage at diagnosis and biological determinants (grading) between White and Black women.