title: Determinants of serum total and free testosterone levels in women over the age of 65 years.
abstract: BACKGROUND
  Little is known about testosterone (T) levels and their determinants in women of late postmenopausal age.
  
  
  OBJECTIVE
  We describe levels of total and free T and selected factors that influence these levels in a random sample of older women.
  
  
  METHODS
  Levels of serum total T and free T by microdialysis were measured using ultrasensitive assays in 347 community-dwelling women aged 65-98 yr enrolled in the Cardiovascular Health Study. Cross-sectional analyses were performed to define factors associated with total and free T levels.
  
  
  RESULTS
  In adjusted models: 1) total T levels declined with age until 80, whereas free T levels did not vary by age; 2) women with bilateral oophorectomy had 23% lower total T and 16% lower free T levels than those with at least one intact ovary; 3) oral estrogen users had total and free T levels that were 47% lower than never users; 4) obese women had 47% higher total T and 20% higher free T levels, and overweight women had 24% higher total T and 14% higher free T levels, than normal weight women; and 5) free T levels were 51% higher in black women. Corticosteroid users had 75% lower total T and 43% lower free T levels than nonusers.
  
  
  CONCLUSIONS
  Bilateral oophorectomy, estrogen use, corticosteroid use, and low body mass index are independent risk factors for lower T levels in women aged 65 yr and over. Although highly prevalent in women of this age, the physiological significance of low T levels in late postmenopausal women requires further investigation.
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6021, USA. acappola@cceb.med.upenn.edu
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Ratcliffe
authors.forename: Shalender
authors.initials: S
authors.lastname: Bhasin
authors.forename: Marc R
authors.initials: MR
authors.lastname: Blackman
authors.forename: Jane
authors.initials: J
authors.lastname: Cauley
authors.forename: John
authors.initials: J
authors.lastname: Robbins
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Zmuda
authors.forename: Tamara
authors.initials: T
authors.lastname: Harris
authors.forename: Linda P
authors.initials: LP
authors.lastname: Fried
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D007006:Hypogonadism / Q000097:blood* / Q000453:epidemiology*; D015999:Multivariate Analysis; D017711:Nonlinear Dynamics; D009765:Obesity / Q000097:blood / Q000453:epidemiology; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology; D017698:Postmenopause / Q000097:blood*; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D013739:Testosterone / Q000097:blood* / Q000172:deficiency
chemical_list: D013739:Testosterone