title: Racial/ethnic differences in initiation of adjuvant hormonal therapy among women with hormone receptor-positive breast cancer.
abstract: Mortality after breast cancer diagnosis is known to vary by race/ethnicity even after adjustment for differences in tumor characteristics. As adjuvant hormonal therapy decreases risk of recurrence and increases overall survival among women with hormone receptor-positive tumors, treatment disparities may play a role. We explored racial/ethnic differences in initiation of adjuvant hormonal therapy, defined as two or more prescriptions for tamoxifen or aromatase inhibitor filled within the first year after diagnosis of hormone receptor-positive localized or regional-stage breast cancer. The sample included women diagnosed with breast cancer enrolled in Kaiser Permanente Northern California (KPNC). Odds ratios [OR] and 95% confidence intervals [CI] compared initiation by race/ethnicity (Hispanic, African American, Chinese, Japanese, Filipino, and South Asian vs. non-Hispanic White [NHW]) using logistic regression. Covariates included age and year of diagnosis, area-level socioeconomic status, co-morbidities, tumor stage, histology, grade, breast cancer surgery, radiation and chemotherapy use. Our sample included 13,753 women aged 20-79 years, diagnosed between 1996 and 2007, and 70% initiated adjuvant hormonal therapy. In multivariable analysis, Hispanic and Chinese women were less likely than NHW women to initiate adjuvant hormonal therapy ([OR] = 0.82; [CI] 0.71-0.96 and [OR] = 0.78; [CI] 0.63-0.98, respectively). Within an equal access, insured population, lower levels of initiation of adjuvant hormonal therapy were found for Hispanic and Chinese women. Findings need to be confirmed in other insured populations and the reasons for under-initiation among these groups need to be explored.
authors.affiliation: Department of Health Evidence and Policy, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY 10029, USA. jennifer.livaudais@mssm.edu
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Livaudais
authors.forename: Dawn L
authors.initials: DL
authors.lastname: Hershman
authors.forename: Laurel
authors.initials: L
authors.lastname: Habel
authors.forename: Lawrence
authors.initials: L
authors.lastname: Kushi
authors.forename: Scarlett Lin
authors.initials: SL
authors.lastname: Gomez
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Li
authors.forename: Alfred I
authors.initials: AI
authors.lastname: Neugut
authors.forename: Louis
authors.initials: L
authors.lastname: Fehrenbacher
authors.forename: Beti
authors.initials: B
authors.lastname: Thompson
authors.forename: Gloria D
authors.initials: GD
authors.lastname: Coronado
mesh_terms: D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000453:epidemiology / Q000208:ethnology*; D002140:California / Q000453:epidemiology / Q000208:ethnology; D017024:Chemotherapy, Adjuvant; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008875:Middle Aged
chemical_list: D018931:Antineoplastic Agents, Hormonal