title: Predictors of guideline treatment nonadherence and the impact on survival in patients with colorectal cancer.
abstract: BACKGROUND
  This study investigated the effect of comorbidity, age, health insurance payer status, and race on the risk of patient nonadherence to NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon and Rectal Cancers. In addition, the prognostic impact of NCCN treatment nonadherence on overall survival was assessed.
  
  
  METHODS
  Patients with CRC who received primary treatment at Memorial University Medical Center from 2003 to 2010 were eligible for this study. Modified Poisson regression was used to obtain risk ratios for the outcome of nonadherence with NCCN Guidelines. Hazard ratios (HRs) for the relative risk of death from all causes were obtained through Cox regression.
  
  
  RESULTS
  Guideline-adherent treatment was received by 82.7% of patients. Moderate/severe comorbidity, being uninsured, having rectal cancer, older age, and increasing tumor stage were associated with increased risks of receiving nonadherent treatment. Treatment nonadherence was associated with 3.6 times the risk of death (HR, 3.55; 95% CI, 2.16-5.85) in the first year after diagnosis and an 80% increased risk of death (HR, 1.80; 95% CI, 1.14-2.83) in years 2 to 5. The detrimental effect of nonadherence declined with increasing comorbidity and varied according to age.
  
  
  CONCLUSIONS
  Although medically justifiable reasons exist for deviating from NCCN Guidelines when treating patients with colorectal cancer (CRC), those who received nonadherent treatment had much higher risks of death, especially in the first year after diagnosis. This study's results highlight the importance of cancer health services research to drive quality improvement efforts in cancer care for patients with CRC.
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Hines
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Alina
authors.initials: A
authors.lastname: Barrett
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Philip
authors.initials: P
authors.lastname: Twumasi-Ankrah
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Dominique
authors.initials: D
authors.lastname: Broccoli
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Kimberly K
authors.initials: KK
authors.lastname: Engelman
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Joaquina
authors.initials: J
authors.lastname: Baranda
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Ablah
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Lisette
authors.initials: L
authors.lastname: Jacobson
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Michelle
authors.initials: M
authors.lastname: Redmond
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Wei
authors.initials: W
authors.lastname: Tu
authors.affiliation: From the University of Kansas School of Medicine-Wichita, Wichita, Kansas; Memorial University Medical Center, Savannah, Georgia; University of Kansas Medical Center, Kansas City, Kansas; and Georgia Southern University, Statesboro, Georgia.
authors.forename: Tracie C
authors.initials: TC
authors.lastname: Collins
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D015897:Comorbidity; D005260:Female; D005846:Georgia (Republic) / Q000453:epidemiology; D019983:Guideline Adherence; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D016017:Odds Ratio; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome