title: Examining racial variation in antiemetic use and post-chemotherapy health care utilization for nausea and vomiting among breast cancer patients.
abstract: Racial minority cancer patients may experience underuse of antiemetic medications to prevent chemotherapy-induced nausea and vomiting (CINV). In addition to its adverse implications for quality of life, antiemetic underuse may contribute to observed disparities in acute illness during chemotherapy. To understand the potential contribution of CINV prophylaxis to breast cancer disparities, we assessed racial variation in potent antiemetic use and post-chemotherapy utilization related to CINV and the relationship between the two.
  
  
  
  We used SEER-Medicare data to evaluate the health care utilization in the 14 days following chemotherapy initiation among black and white women receiving highly emetogenic chemotherapy for breast cancer. We used modified Poisson regression to assess the relationship between (1) race and CINV-related utilization and (2) NK1 use and CINV-related utilization, overall and stratified by race. We report adjusted risk ratios (aRR) and 95 % confidence intervals (CI).
  
  
  
  The study included 1130 women. Black women were 11 % less likely than white women to use neurokinin-1 receptor antagonists (NK1s) for CINV prophylaxis (p = 0.02); however, they experienced fewer CINV-related encounters following chemotherapy (unadjusted RR = 0.63, 95 %CI = 0.40-0.99; p = 0.05). After adjustment for clinical covariates, estimates were similar but no longer statistically significant (p = 0.07). Among white women, NK1 use was associated with increased CINV-related utilization (aRR NK1 users vs. non-users: 1.35, 95 % CI = 1.07-1.69, p = 0.01), likely resulting from unmeasured confounders.
  
  
  
  Black women were less likely to use NK1s- and CINV-related services. Racial variation in CINV-related services use may be partly explained by differential symptom reporting or access to care.
authors.affiliation: Department of Health Policy and Management, , CB#7411, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599, USA. devon.k.check@kp.org.
authors.forename: Devon K
authors.initials: DK
authors.lastname: Check
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA.|Division of Hematology/Oncology, UNC School of Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Reeder-Hayes
authors.affiliation: Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center, Durham, NC, USA.|Department of Medicine, Division of General Internal Medicine, Duke University, Durham, NC, USA.
authors.forename: Leah L
authors.initials: LL
authors.lastname: Zullig
authors.affiliation: Department of Health Policy and Management, , CB#7411, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599, USA.|Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center, Durham, NC, USA.
authors.forename: Morris
authors.initials: M
authors.lastname: Weinberger
authors.affiliation: Department of Health Policy and Management, , CB#7411, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599, USA.|Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA.|Division of Hematology/Oncology, UNC School of Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Ethan M
authors.initials: EM
authors.lastname: Basch
authors.affiliation: Department of Health Policy and Management, , CB#7411, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599, USA.|Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA.|Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Stacie B
authors.initials: SB
authors.lastname: Dusetzina
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000932:Antiemetics / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000009:adverse effects*; D044383:Black People; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000208:ethnology*; D005260:Female; D006801:Humans; D009325:Nausea / Q000139:chemically induced / Q000208:ethnology*; D064729:Neurokinin-1 Receptor Antagonists / Q000627:therapeutic use*; D010342:Patient Acceptance of Health Care / Q000208:ethnology*; D011788:Quality of Life; D044469:Racial Groups; D014839:Vomiting / Q000139:chemically induced / Q000208:ethnology*
chemical_list: D000932:Antiemetics; D000970:Antineoplastic Agents; D064729:Neurokinin-1 Receptor Antagonists
keywords: Breast cancer; Neurokinin-1 receptor antagonists; Quality of life