title: Demographic, physical and lifestyle factors associated with androgen status: the Florey Adelaide Male Ageing Study (FAMAS).
abstract: OBJECTIVE
  Plasma androgen levels are inversely associated with health in men, the age-related decline of which may result from factors other than ageing per se. This study aimed to determine the effects of demographic, physical and lifestyle factors on age-related androgen status in men.
  
  
  METHODS
  An observational survey of a regionally representative male population residing in the North West regions of Adelaide, Australia.
  
  
  METHODS
  Study sample includes 1195 men aged 35-81 years with a response rate of 45.1%.
  
  
  METHODS
  Plasma levels of total testosterone (TT), bioavailable testosterone (BT), SHBG, insulin-like peptide 3 (INSL3), and gonadotrophins were measured along with an extensive list of demographic, physical and lifestyle factors including body composition, muscle strength and biomarkers of chronic diseases, physical activity, nutrition and smoking behaviour.
  
  
  RESULTS
  Low TT was mostly associated with high abdominal fat and triglycerides and low muscle strength rather than ageing per se. Low BT was associated with increased age followed by high whole body fat percentage. BT and TT levels were higher in unmarried men and smokers. SHBG levels increased with age, but were also inversely associated with insulin and triglycerides. The Leydig cell specific factor INSL3 was the strongest biomarker associated with both TT and BT.
  
  
  CONCLUSIONS
  Factors associated with low androgen status variably include high body fat percentage, low muscle strength and biomarkers of the metabolic syndrome. Reducing exposure to factors that adversely affect androgen status may improve the general health of ageing men by mechanisms yet to be defined.
authors.affiliation: Faculty of Health Sciences, The University of Sydney, Sydney, NSW, Australia. e.atlantis@usyd.edu.au
authors.forename: Evan
authors.initials: E
authors.lastname: Atlantis
authors.forename: Sean A
authors.initials: SA
authors.lastname: Martin
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Haren
authors.forename: Peter D
authors.initials: PD
authors.lastname: O'Loughlin
authors.forename: Anne W
authors.initials: AW
authors.lastname: Taylor
authors.forename: Ravinder
authors.initials: R
authors.lastname: Anand-Ivell
authors.forename: Richard
authors.initials: R
authors.lastname: Ivell
authors.forename: Gary A
authors.initials: GA
authors.lastname: Wittert
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood; D000728:Androgens / Q000097:blood*; D001315:Australia; D001823:Body Composition; D006304:Health Status; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D013739:Testosterone / Q000097:blood*
chemical_list: D000728:Androgens; D013739:Testosterone