title: Testosterone and dihydrotestosterone and incident ischaemic stroke in men in the Cardiovascular Health Study.
abstract: OBJECTIVE
  Ischaemic stroke is a major cause of morbidity and mortality in elderly men. Our main objective was to examine whether testosterone (T) or dihydrotestosterone (DHT) was associated with incident ischaemic stroke in elderly men.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  Elderly men in the Cardiovascular Health Study who had no history of stroke, heart disease or prostate cancer as of 1994 and were followed until December 2010.
  
  
  METHODS
  Adjudicated ischaemic stroke.
  
  
  RESULTS
  Among 1032 men (mean age 76, range 66-97), followed for a median of 10 years, 114 had an incident ischaemic stroke. Total T and free T were not significantly associated with stroke risk, while DHT had a nonlinear association with incident stroke (P = 0·006) in analyses adjusted for stroke risk factors. The lowest risk of stroke was at DHT levels of 50-75 ng/dl, with greater risk of stroke at DHT levels above 75 ng/dl or below 50 ng/dl. Results were unchanged when SHBG was added to the model. Calculated free DHT had an inverse linear association with incident ischaemic stroke with HR 0·77 (95% CI, 0·61, 0·98) per standard deviation in analyses adjusted for stroke risk factors.
  
  
  CONCLUSIONS
  Dihydrotestosterone had a nonlinear association with stroke risk in which there was an optimal DHT level associated with the lowest stroke risk. Further studies are needed to confirm these results and to clarify whether there is an optimal androgen range associated with the least risk of adverse outcomes in elderly men.
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA; Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
authors.forename: Molly M
authors.initials: MM
authors.lastname: Shores
authors.forename: Alice M
authors.initials: AM
authors.lastname: Arnold
authors.forename: Mary L
authors.initials: ML
authors.lastname: Biggs
authors.forename: W T
authors.initials: WT
authors.lastname: Longstreth
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Smith
authors.forename: Jorge R
authors.initials: JR
authors.lastname: Kizer
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
authors.forename: Calvin H
authors.initials: CH
authors.lastname: Hirsch
authors.forename: Brett T
authors.initials: BT
authors.lastname: Marck
authors.forename: Alvin M
authors.initials: AM
authors.lastname: Matsumoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000097:blood* / Q000453:epidemiology*; D002320:Cardiovascular Physiological Phenomena; D013196:Dihydrotestosterone / Q000097:blood*; D006262:Health; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D020521:Stroke / Q000097:blood* / Q000453:epidemiology*; D013739:Testosterone / Q000097:blood*
chemical_list: D013196:Dihydrotestosterone; D013739:Testosterone