A prospective assessment of racial/ethnic differences in future mammography behavior among women who had early mammography.
BACKGROUND
Twenty-nine percent of women, aged 30 to 39, report having had a mammogram, though sensitivity and specificity are low. We investigate racial/ethnic differences in future mammography behavior among women who had a baseline screening mammogram prior to age 40.


METHODS
Using 1994-2008 data from the Breast Cancer Surveillance Consortium (BCSC), we identified 29,390 women aged 35 to 39 with a baseline screening mammogram. We followed this cohort for 2 outcomes: (i) future BCSC mammography between ages 40 and 45; and (2) among those, delay in screening mammography until ages 43 to 45 compared with ages 40 to 42. Using adjusted log-linear models, we estimated the relative risk (RR) of these outcomes by race/ethnicity, while also considering the impact of false-positive/true-negative (FP/TN) baseline mammography results on these outcomes.


RESULTS
Relative to non-Hispanic white women, Hispanic women had an increased risk of no future BCSC mammography (RR: 1.21, 95% CI: 1.13-1.30); Asian women had a decreased risk (RR: 0.67, 95% CI: 0.61-0.74). Women with a FP result, compared with a TN result, had a decreased risk of no future BCSC mammography (RR: 0.89, 95% CI: 0.85-0.95). Among those with future BCSC screening mammography, African American women were more likely to delay the timing (RR: 1.26, 95% CI: 1.09-1.45). The interaction between race/ethnicity and FP/TN baseline results was not significant.


CONCLUSIONS
Race/ethnicity is differentially associated with future BCSC mammography and the timing of screening mammography after age 40.


IMPACT
These findings introduce the need for research that examines disparities in lifetime mammography use patterns from the initiation of mammography screening.