Spatial patterns of breast cancer incidence and uninsured women of mammography screening age.

Breast cancer is the most common cancer and second leading cause of cancer mortality in women in the United States. Women who lack insurance have mammography screening rates that are suboptimal. Our objective was to spatially correlate incidence rates of breast cancer and uninsured women aged 40-64 years and identify outliers-areas where women may be underscreened due to poor access. The eight-county consolidated metropolitan statistical area centered on Harris County, Texas was selected as the study region. Breast cancer incidence data from 1995 to 2004 were acquired from the State of Texas Cancer Registry as individual case data geocoded at the census tract level. A bivariate local indicator of spatial autocorrelation was used to evaluate the spatial pattern of breast cancer incidence and uninsured. Statistically significant negative spatial autocorrelation was observed between breast cancer incidence and uninsured status in women aged 40-64 (Moran's I -0.2065, p < 0.001), indicating that as breast cancer incidence increased, uninsured rates decreased globally. Statistically significant local clusters of low breast cancer incidence and high incidence of uninsured were found. Future research is needed to assess mammography screening behaviors and barriers to screening at the local level.