Moraska, A. R., Atherton, P. J., Szydlo, D. W., Barton, D. L., Stella, P. J., Rowland, K. M.,Jr, . . . Loprinzi, C. L. (2010). Gabapentin for the management of hot flashes in prostate cancer survivors: a longitudinal continuation Study-NCCTG Trial N00CB. The Journal of Supportive Oncology, 8(3), 128-132.

Study Purpose

Examined efficacy and toxicity of gabapentin when taken for additional 8 weeks after previous study, where it was compared 3 different doses of gabapentin with placebo for treatment of hot flashes due to androgen deprivation therapy

 

Intervention Characteristics/Basic Study Process

Self completed report by participants

Sample Characteristics

  • N :  Evaluable 147, data for 117 
  • AGE: Mean 69.4 years old
  • MALES: (%) 100% males    FEMALES: (%) NO
  • KEY DISEASE CHARACTERISTICS: Prostate cancer  
  • OTHER KEY SAMPLE CHARACTERISTICS:  
    • Men with history of prostate cancer, on stable androgen deprivation therapy,  experiencing troublesome hot flashes
    • No renal insufficiency or previous used of gabapentin or concurrent use of any other chemotherapy or hormone treatment
       

Setting

SITE: Mutli-site    
 

Phase of Care and Clinical Applications

PHASE OF CARE: Transition phase after initial treatment

APPLICATIONS: Late Effects & Survivorship; End of Life and Palliative Care
 

Study Design

Observational, open label, and uncontrolled design continuation of randomized study

Measurement Instruments/Methods

  • Patients received a booklet containing instructions     
  • Patients received a set of hot flash diaries to be completed daily
  • Patients received symptoms experience diaries to be completed weekly, addressing adverse effects: decreased appetite, nausea, dry mouth, dizziness, fatigue, trouble walking or balance problems, muscle pain, difficulty with concentration, constipation, sleepiness/sleep problems, blurred vision, anxiety, and mood changes; also included quality of life and satisfaction with hot flash control (0 none to 10 worst)
  • Quality of Life measured by the Profile of Mood States-Brief (POMS-B)- baseline week and after he 4 weeks of treatment
     

Results

 600 mg/d  of gabapentin moderately decreased the hot flash score without substantial toxicities.  All groups decreased hot flash scores and frequency at similar levels. Appetite loss and constipation were not increased. Troubled sleeping and nervousness scores were better in the placebo group.

Conclusions

  • Gabapentin moderately decreases hot flash scores and frequencies without important toxicities over 8 weeks. 
  • Doses of 600-900 mg/d of gabapentin show better results for treating hot flashes than 300 mg/d.

Limitations

  •  Continuation phase:  observational, open label, and uncontrolled

Nursing Implications

  • Results from the study should be cautiously generalized because of patient subjective ratings.
  • The study was not controlled or randomized.
  • There was some possible recruitment bias for those patients with better adherence to medical instructions.