Temporal trends in area socioeconomic disparities in breast-cancer incidence and mortality, 1988-2005

Since an overarching goal of Healthy People 2010 was to eliminate health disparities, we determined temporal trends in socioeconomic disparities in five breast-cancer indicators (in situ, stage I, lymph-node positive, and locally advanced breast-cancer incidence, and breast-cancer mortality) by county socioeconomic deprivation using 1988-2005 population-based breast-cancer data. Using 1988-2005 data from women aged 40 and older from 200 counties in the Surveillance, Epidemiology, and End Results program, we examined trends in temporal disparities in the five breast-cancer indicators across quartiles of county socioeconomic deprivation. County-level trends were summarized using the estimated annual percentage change. Observed county rates were smoothed using Bayesian hierarchical spatiotemporal methods to calculate measures of absolute and relative disparity (using absolute and relative concentration indices) and their changes over time. Large increases in in situ breast cancer rates since 1988 were observed for each of the deprivation quartiles. Absolute and relative disparity both increased over time, suggesting increasing disparities across levels of county deprivation. Absolute and relative concentration indices were near zero for the other four breast-cancer indicators, suggesting no disparities among the four quartiles of county deprivation during 1988-2005. Efforts to target counties aimed at increasing breast-cancer screening based on their level of deprivation will not likely be beneficial.