title: How long do patients with erectile dysfunction continue to use sildenafil citrate? Dropout rate from treatment course as outcome in real life.
abstract: OBJECTIVE
  To study the dropout rate for use of sildenafil after initial prescription and during successful treatment to clarify their risk factors.
  
  
  METHODS
  A total of 1036 patients with erectile dysfunction who were treated with sildenafil were analyzed. The dropout rate during successful treatment and its risk factors were assessed using the Kaplan-Meier method and Cox proportional hazards model, respectively.
  
  
  RESULTS
  Thirty-one percent (n = 322) of the patients dropped out after the initial prescription. The cumulative dropout rate during successful treatment at 3 years after starting usage was 48%. A lower International Index of Erectile Function (IIEF-5) score before treatment was a significant risk factor for dropout during a successful treatment course (P < 0.029 by the Cox proportional hazards model).
  
  
  CONCLUSIONS
  Approximately 30% and 50% of the patients dropped out of treatment after the first prescription and at 3-year follow-up, respectively. Adequate initial instruction and long-term follow-up are required even for patients with successful treatment.
authors.affiliation: Sanjukai Urological Hospital, Sapporo, Japan. ysato@sanjukai.or.jp
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Sato
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tanda
authors.forename: Shuji
authors.initials: S
authors.lastname: Kato
authors.forename: Shigeki
authors.initials: S
authors.lastname: Onishi
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Nitta
authors.forename: Mikio
authors.initials: M
authors.lastname: Koroku
mesh_terms: D000328:Adult; D000368:Aged; D004334:Drug Administration Schedule; D007172:Erectile Dysfunction / Q000188:drug therapy*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010352:Patient Dropouts / Q000706:statistics & numerical data*; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage*; D010879:Piperazines / Q000008:administration & dosage*; D011687:Purines / Q000008:administration & dosage; D012307:Risk Factors; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000008:administration & dosage*; D016896:Treatment Outcome; D016312:Treatment Refusal / Q000706:statistics & numerical data*
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate