title: Characteristics, survival, and related factors of newly diagnosed colorectal cancer patients refusing cancer treatments under a universal health insurance program.
abstract: BACKGROUND
  Colorectal cancer is the third most commonly diagnosed cancer worldwide. Few studies have addressed the causes and risks of treatment refusal in a universal health insurance setting.
  
  
  METHODS
  We examined the characteristics and survival associated with treatment refusal in patients with newly diagnosed colorectal cancer in Taiwan during 2004-2008. Treatment refusal was defined as not undergoing any cancer treatment within 4 months of confirmed cancer diagnosis. Patient data were extracted from four national databases. Factors associated with treatment refusal were identified through logistic regression using the generalized estimating equation method, and survival analysis was performed using the Cox proportional hazards model.
  
  
  RESULTS
  Of the 41,340 new colorectal cancer cases diagnosed, 3,612 patients (8.74%) refused treatment. Treatment refusal rate was higher in patients with less urbanized areas of residence, lower incomes, preexisting catastrophic illnesses, cancer stages of 0 and IV, and diagnoses at regional and district hospitals. Logistic regression analysis revealed that patients aged >75 years were the most likely to refuse treatment (OR, 1.87); patients with catastrophic illnesses (OR, 1.66) and stage IV cancer (OR, 1.43) had significantly higher refusal rates. The treatment refusers had 2.66 times the risk of death of those who received treatment. Factors associated with an increased risk of death in refusers included age ≥ 75 years, insured monthly salary ≥ 22,801 NTD, low-income household or aboriginal status, and advanced cancer stage (especially stage IV; HR, 11.33).
  
  
  CONCLUSIONS
  Our results show a lower 5-year survival for colorectal patients who refused treatment than for those who underwent treatment within 4 months. An age of 75 years or older, low-income household status, advanced stages of cancer, especially stage IV, were associated with higher risks of death for those who refused treatment.
authors.forename: Chun-Yi
authors.initials: CY
authors.lastname: Liu
authors.forename: William Tzu-Liang
authors.initials: WT
authors.lastname: Chen
authors.forename: Pei-Tseng
authors.initials: PT
authors.lastname: Kung
authors.forename: Chang-Fang
authors.initials: CF
authors.lastname: Chiu
authors.forename: Yueh-Hsin
authors.initials: YH
authors.lastname: Wang
authors.forename: Shwn-Huey
authors.initials: SH
authors.lastname: Shieh
authors.affiliation: Department of Health Services Administration, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan. wtsai@mail.cmu.edu.tw.
authors.forename: Wen-Chen
authors.initials: WC
authors.lastname: Tsai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007348:Insurance, Health; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012042:Registries; D012307:Risk Factors; D016019:Survival Analysis; D013624:Taiwan; D016312:Treatment Refusal; D055815:Young Adult