title: Recovery of urinary function after radical prostatectomy: identification of trajectory cluster groups.
abstract: OBJECTIVE
  Post-prostatectomy urinary incontinence can impact health related quality of life in men treated with radical prostatectomy for prostate cancer. Currently no consensus exists on which patients are at risk for impaired health related quality of life secondary to post-prostatectomy urinary incontinence. Using trajectory clustering analysis we identified predictors of post-prostatectomy urinary incontinence recovery in unique patient groups.
  
  
  METHODS
  In a 5-year period health related quality of life was evaluated in patients treated with radical prostatectomy using UCLA-PCI preoperatively, and 3, 6 and 12 months postoperatively. We used a novel cluster modeling technique to identify unique group trajectories of urinary function recovery with time.
  
  
  RESULTS
  Group based modeling of UCLA-PCI urinary function scores identified 3 distinct post-prostatectomy urinary incontinence recovery patterns. The 73 group 1 patients had a significant postoperative decrease with only 33.4% of optimum function at 12 months. The 258 group 2 patients had moderately decreased urinary function at 3 months with improvement to 76.8% of optimum function at 12 months. The 89 group 3 patients had high scores throughout. Group 1 patients tended to be older (p=0.001), have major depression (p=0.008) and lower extremity circulatory disease (p=0.004), be a past or a current smoker (p=0.004) and have more comorbidities (p<0.001) than those in groups 2 and 3. On multivariate analysis age and the number of comorbidities significantly predicted inclusion in the poor function group.
  
  
  CONCLUSIONS
  A novel modeling approach identified 3 distinct post-prostatectomy urinary incontinence recovery patterns. Patient age and the number of comorbidities predicted worse outcome. These findings have implications for preoperative patient counseling and early intervention for post-prostatectomy urinary incontinence.
authors.affiliation: Department of Urologic Surgery, Vanderbilt University Medical Center, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232, USA. c.anderson@vanderbilt.edu
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Anderson
authors.forename: Melissa R
authors.initials: MR
authors.lastname: Kaufman
authors.forename: Mary S
authors.initials: MS
authors.lastname: Dietrich
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Barocas
authors.forename: Sam S
authors.initials: SS
authors.lastname: Chang
authors.forename: Michael S
authors.initials: MS
authors.lastname: Cookson
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Smith
authors.forename: Peter E
authors.initials: PE
authors.lastname: Clark
authors.forename: S Duke
authors.initials: SD
authors.lastname: Herrell
mesh_terms: D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011468:Prostatectomy / Q000379:methods; D020127:Recovery of Function; D014554:Urination