title: The effect of severe androgen deficiency on physical function in male patients with cancer.
abstract: BACKGROUND
  Low circulating testosterone concentrations are commonly observed in male patients with cancer and have been shown to be associated with weight loss and increased severity of many symptoms, including fatigue and weakness.
  
  
  OBJECTIVE
  The aim of the present study was to determine the extent to which testosterone deficiency is associated with poor physical function in male patients with nonhormonal cancers.
  
  
  METHODS
  We measured serum free testosterone concentration in 101 male patients with cancer evaluated at a nutrition-rehabilitation clinic and performed univariate and multivariate linear regression analyses to assess the effect of a free testosterone concentration in the lowest quartile on six-minute walk distance (6-MWD) (n=100) and maximal gait speed (n=49).
  
  
  RESULTS
  In the univariate analyses, patients in the lowest free testosterone quartile had a 6-MWD that was 96 m (95% CI 51, 141) less and a maximal gait speed that was 0.26 m/second (95% CI 0.06, 0.47) slower on average than patients in the upper three free testosterone quartiles. When controlling for other demographic, clinical, and biological factors, a free testosterone concentration in the lowest quartile was associated, on average, with a 51 m (95% CI 44, 97) lower 6-MWD but did not affect maximal gait speed.
  
  
  CONCLUSIONS
  The present study shows that in male patients with cancer, an extremely low serum free testosterone concentration is independently associated with 6-MWD but not maximal gait speed. Hence, a severe testosterone deficiency may impair their ability to perform sustained activity, but to a lesser degree, short bursts of activity.
authors.affiliation: Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada. bruno.gagnon@mcgill.ca
authors.forename: Bruno
authors.initials: B
authors.lastname: Gagnon
authors.forename: Jessica
authors.initials: J
authors.lastname: Murphy
authors.forename: Marta
authors.initials: M
authors.lastname: Jelowicki
authors.forename: David V
authors.initials: DV
authors.lastname: Morris
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000728:Androgens / Q000097:blood* / Q000172:deficiency*; D015897:Comorbidity; D017079:Exercise Tolerance; D005221:Fatigue / Q000453:epidemiology* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009369:Neoplasms / Q000453:epidemiology* / Q000503:physiopathology*; D015995:Prevalence; D011792:Quebec / Q000453:epidemiology; D012307:Risk Factors
chemical_list: D000728:Androgens