Disparities in Medical Care Among Commercially Insured Patients With Newly Diagnosed Breast Cancer: Opportunities for Intervention

African-American women have increased breast cancer mortality compared with white women. Diagnostic and treatment gaps may contribute to this disparity. In this retrospective, longitudinal cohort study, Southern US health plan claims data and linked medical charts were used to identify racial disparities in the diagnoses, treatment, and mortality of commercially insured women with newly diagnosed breast cancer. White women (n = 476) and African-American women (n = 99) with newly diagnosed breast cancer were identified by breast cancer claims codes (International Classification of Diseases, Ninth Revision, Clinical Modification codes 174, 233.0, 238.3, and 239.3) between January 2000 and December 2004. Race, diagnoses (breast cancer stage, estrogen/progesterone receptor [ER/PR]-positive status), treatment (breast-conserving surgery, antiestrogen therapy, and chemotherapy interruption or reduction), and all-cause mortality were assessed from medical charts. Multivariate regression analyses were adjusted for age, geography, and socioeconomic status to test the association of race with diagnoses/treatment. White women were older (P < .001) and had higher rates of diagnosis at stage 0/I (55.2% vs 38.4%; P < .05) than African-American women. More white women had positive ER/PR status (75% vs 56% African-American; P = .001) and received antiestrogen therapy if they were positive (37.2% vs 27.3% African-American; P < .001). White women received slightly more breast-conserving surgery and chemotherapy dose modification than African-American women (P value nonsignificant). African-American women had a higher mortality rate (8.1%) than white women (3.6%; P = .06). In adjusted analyses, African-American women were diagnosed at later stages (odds ratio, 1.71; P = .02), and white women received more antiestrogen therapy (odds ratio, 2.1; P = .03). Disparities in medical care among patients with newly diagnosed breast cancer were evident between African-American women and white women despite health plan insurance coverage. Interventions that address the gaps identified are needed.