title: The effect of age on race-related breast cancer survival disparities.
abstract: BACKGROUND
  Breast cancer survival disparities by race are likely multifactorial. In a small pilot cohort, we demonstrated a statistical interaction between age and race. The purpose of this study was to validate earlier findings in a larger, more diverse cohort and to test the hypothesis that breast cancer survival is influenced by the dependent relationship of age and race.
  
  
  METHODS
  We conducted a retrospective analysis of a multi-institutional breast cancer database for patients treated between 1999 and 2009. Study variables included age and disease stage at diagnosis, race, treatment (surgery, chemotherapy, radiotherapy, hormone therapy) and overall survival. Statistical analysis and regression models were performed by Stata software.
  
  
  RESULTS
  A total of 9,249 patients were included in this study. African American, Hispanic, and Asian patients were more likely to present at a younger age with metastases. African American and Hispanic race were associated with increased mortality after adjusting for stage, age, and treatment. A 2-way interaction between age and race was identified in the Cox regression model (p < 0.001). To further define this interaction, a postestimation analysis was performed to determine the predicted relative hazard for each race with age fixed at 40, 50, 60, 70, and 80 years. At younger ages, the predicted relative hazard was significantly higher for both African American and Hispanic race.
  
  
  CONCLUSIONS
  Despite adjusting for stage and treatment differences, African American and Hispanic race predicted poor survival. The effect of age and treatment on breast cancer survival differs across races. Additional research is needed to accurately determine the reasons for worsened survival.
authors: Department of Surgery, University of Texas Medical School at Houston, Houston, TX, USA. curtis.j.wray@uth.tmc.edu
authors: Curtis J
authors: CJ
authors: Wray
authors: Uma R
authors: UR
authors: Phatak
authors: Emily K
authors: EK
authors: Robinson
authors: Rebecca L
authors: RL
authors: Wiatek
authors: Alyssa G
authors: AG
authors: Rieber
authors: Anneliese
authors: A
authors: Gonzalez
authors: Tien C
authors: TC
authors: Ko
authors: Lillian S
authors: LS
authors: Kao
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data*; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000706:statistics & numerical data; D001943:Breast Neoplasms / Q000208:ethnology* / Q000378:metabolism / Q000473:pathology*; D016001:Confidence Intervals; D005260:Female; D054624:Health Status Disparities; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D016017:Odds Ratio; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies; D014481:United States; D044465:White People / Q000706:statistics & numerical data
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone