title: Elevated LH predicts ischaemic heart disease events in older men: the Health in Men Study.
abstract: BACKGROUND
  Hypogonadism in men is associated with insulin resistance, elevations in pro-inflammatory cytokines and fibrinogen, and an atherogenic lipid profile. However, it is uncertain whether the age-related decline in testosterone is associated with ischaemic heart disease (IHD) events.
  
  
  OBJECTIVE
  To determine whether testosterone and its associated hormones, sex hormone-binding globulin (SHBG) and LH, predict IHD events in older men.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Between 2001 and 2004, 3637 community-dwelling men aged 70-88 years underwent a clinical assessment of cardiovascular risk factors and biochemical assessment of testosterone, SHBG and LH. Free testosterone was calculated using mass action equations. Participants were followed until December 2008 using electronic record linkage to capture IHD events (hospital admission or death).
  
  
  RESULTS
  Mean follow-up was 5.1 years. During this period, 618 men (17.0%; 95% confidence interval (CI) 15.8, 18.3%) experienced an event, of which 160 were fatal. Men with higher baseline total or free testosterone levels experienced fewer IHD events (hazard ratio (HR)=0.89; 95% CI 0.82, 0.97 and HR=0.86; 95% CI 0.79, 0.94 for each one s.d. increase in total and free testosterone respectively). These associations were maintained after adjustment for age and waist:hip ratio but did not persist after adjustment for prevalent IHD or other cardiovascular risk factors. SHBG was not associated with IHD events. In contrast, higher LH levels were associated with reduced event-free survival in both univariate (HR=1.15; 95% CI 1.08, 1.22) and adjusted analyses (HR=1.08; 95% CI 1.01, 1.15).
  
  
  CONCLUSIONS
  Dysregulation of the hypothalamic-pituitary-gonadal axis may be a risk factor for IHD. Further studies of men with either elevated LH or low testosterone are warranted.
authors.affiliation: Western Australian Centre for Health and Ageing (M570), Centre for Medical Research, Western Australian Institute for Medical Research School of Medicine and Pharmacology School of Surgery, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
authors.forename: Zoë
authors.initials: Z
authors.lastname: Hyde
authors.forename: Paul E
authors.initials: PE
authors.lastname: Norman
authors.forename: Leon
authors.initials: L
authors.lastname: Flicker
authors.forename: Graeme J
authors.initials: GJ
authors.lastname: Hankey
authors.forename: Kieran A
authors.initials: KA
authors.lastname: McCaul
authors.forename: Osvaldo P
authors.initials: OP
authors.lastname: Almeida
authors.forename: S A Paul
authors.initials: SA
authors.lastname: Chubb
authors.forename: Bu B
authors.initials: BB
authors.lastname: Yeap
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D053208:Kaplan-Meier Estimate; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D017202:Myocardial Ischemia / Q000097:blood* / Q000453:epidemiology* / Q000401:mortality; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood
chemical_list: D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D007986:Luteinizing Hormone