title: Preoperative constipation is associated with poor prognosis of rectal cancer: a prospective cohort study.
abstract: OBJECTIVE
  It is unknown whether patients with advanced rectal cancer develop severe constipation. Therefore, the objective of this study was to assess whether constipation severity is associated with pathologic progression of rectal cancer.
  
  
  METHODS
  We analyzed 472 patients with rectal cancer who underwent elective surgical resection between January 2005 and December 2010. Constipation severity was prospectively evaluated in 407 patients (86.2%) using the Cleveland Clinic Constipation Score System. Linear regression analysis was performed to identify clinicopathologic variables associated with constipation. Kaplan-Meier analysis and Cox proportional hazard models were used to evaluate the prognostic value of constipation severity on disease-free and overall survival.
  
  
  RESULTS
  Multivariable analysis showed that sex (regression coefficient [B] = 1.55; 95% confidence interval [CI], 0.79 to 2.60; P < 0.001), body mass index (B = -0.95; 95% CI, -1.83 to -0.64; P = 0.036), tumor size (B = 1.04; 95% CI, 0.20 to 1.88; P = 0.016), T stage (B = 0.75; 95% CI, 0.23 to 1.27; P = 0.005), and distant metastasis (B = 1.16; 95% CI, 0.03 to 2.30; P = 0.045) were associated with constipation severity. Severe constipation (score ≥ 8) was independently associated with 3-year disease-free survival (vs. scores of 0-3; hazard ratio [HR], 2.39; 95% CI, 1.15 to 4.98; P = 0.020) and 5-year overall survival (HR, 2.30; 95% CI, 1.23 to 4.30; P = 0.009) in multivariable analysis.
  
  
  CONCLUSIONS
  Our results suggest that preoperative constipation severity is associated with advanced pathologic stage and poor oncologic outcomes in patients with rectal cancer.
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Gil-Yong
authors.initials: GY
authors.lastname: Lee
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Je-Ho
authors.initials: JH
authors.lastname: Jang
authors.forename: Heung-Kwon
authors.initials: HK
authors.lastname: Oh
authors.forename: Duck-Woo
authors.initials: DW
authors.lastname: Kim
authors.forename: Soyeon
authors.initials: S
authors.lastname: Ahn
authors.forename: Sung-Bum
authors.initials: SB
authors.lastname: Kang
keywords: Constipation; Questionnaire; Rectal neoplasms