title: An analysis of testosterone implants for androgen replacement therapy.
abstract: OBJECTIVE
  To review 13 years of experience using fused crystalline testosterone implants for androgen replacement therapy in order to identify pattern of usage (including continuation rates) and adverse events emerging during therapy and factors associated with adverse events including implant extrusions.
  
  
  METHODS
  Retrospective review of prospectively collected data on characteristics of patients and implant procedures performed as well as adverse events reported during routine follow-up.
  
  
  METHODS
  Over 13 years 973 implant procedures using fused crystalline testosterone implants were performed in 221 men.
  
  
  METHODS
  Continuation rates and adverse events such as extrusions, bleeding, infection or others were recorded and analysed in relationship to characteristics of the patient and the implant procedure performed.
  
  
  RESULTS
  Overall rate of adverse events (108/73, 11.1%) was significantly related to increased numbers of implants (4.2 +/- 0.1 vs 4.0 +/- 0.03, P = 0.031) and higher levels of physical activity at work (P = 0.030). The most common adverse effect was extrusion (83/973, 8.5%) which was related to occupational classification (P = 0.033) and increasing work activity (P = 0.044) and occurred more frequently than by chance in multiple (16 vs 3.3 expected) rather than single (65 vs 76.1 expected) episodes. Bleeding (22/973, 2.3%) was significantly associated with an increased number of implants (4.5 +/- 0.2 vs 4.0 +/- 0.03, P = 0.020) but even in the worst cases (3/22) it was of minor clinical importance. Infection was rare (6/973, 0.6%) but occurred more among thinner men. The overall continuation rate was 92.7% increasing from 86% after the first implantation to > 99% after the tenth implant.
  
  
  CONCLUSIONS
  This study demonstrates the very satisfactory clinical acceptability of testosterone pellet implants for androgen replacement therapy within a single unit with experienced operators. The only regular adverse effect is extrusion, which may be related to mechanical factors such as habitual work activity but also possibly procedural factors. Other adverse effects such as bleeding, infection and fibrosis were rare. An improved method of implant delivery would enhance this old but durable technology.
authors.affiliation: Andrology Unit, Royal Price Alfred Hospital, Sydney NSW, Australia. djh@med.su.oz.au
authors.forename: D J
authors.initials: DJ
authors.lastname: Handelsman
authors.forename: M A
authors.initials: MA
authors.lastname: Mackey
authors.forename: C
authors.initials: C
authors.lastname: Howe
authors.forename: L
authors.initials: L
authors.lastname: Turner
authors.forename: A J
authors.initials: AJ
authors.lastname: Conway
mesh_terms: D000328:Adult; D004343:Drug Implants; D005069:Evaluation Studies as Topic; D006801:Humans; D007006:Hypogonadism / Q000188:drug therapy*; D008297:Male; D017060:Patient Satisfaction; D012189:Retrospective Studies; D013739:Testosterone / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D004343:Drug Implants; D013739:Testosterone