title: Association of low leptin with cardiovascular events and mortality in patients with stable coronary artery disease: the Heart and Soul Study.
abstract: OBJECTIVE
  Leptin is an adipokine with both protective and harmful effects on the cardiovascular (CV) system. Prior studies evaluating the association between leptin and CV outcomes have yielded conflicting results. Thus, we sought to investigate the relationship between leptin and CV events and mortality in patients with chronic stable coronary artery disease (CAD).
  
  
  METHODS
  We performed a prospective cohort study of 981 outpatients with stable CAD. Leptin levels were measured in fasting venous samples at baseline. We used proportional hazards models to evaluate the association of baseline leptin with subsequent CV events (myocardial infarction, stroke, transient ischemic attack) and death.
  
  
  RESULTS
  During a mean follow-up of 6.2±2.1 years, there were 304 deaths, 112 myocardial infarctions, and 52 strokes/TIAs. In models adjusted for age, sex, and race, low leptin was associated with a 30% increased risk of the combined outcome (HR 1.30, CI 1.05-1.59, p=0.01). After further adjustment for obesity, traditional CV risk factors and biomarkers, low leptin remained associated with a 37% increased risk of events (HR 1.37, CI 1.06-1.76, p=0.02).
  
  
  CONCLUSIONS
  Low leptin is associated with increased CV events and mortality in patients with stable coronary artery disease. This association is independent of known factors affecting leptin levels, including gender and obesity.
authors.affiliation: Department of Medicine, University of California, San Francisco, CA, USA. ivy.ku@ucsf.edu
authors.forename: Ivy A
authors.initials: IA
authors.lastname: Ku
authors.forename: Ramin
authors.initials: R
authors.lastname: Farzaneh-Far
authors.forename: Eric
authors.initials: E
authors.lastname: Vittinghoff
authors.forename: Mary H
authors.initials: MH
authors.lastname: Zhang
authors.forename: Beeya
authors.initials: B
authors.lastname: Na
authors.forename: Mary A
authors.initials: MA
authors.lastname: Whooley
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000401:mortality*; D016009:Chi-Square Distribution; D002908:Chronic Disease; D003324:Coronary Artery Disease / Q000097:blood* / Q000401:mortality*; D015536:Down-Regulation; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000097:blood / Q000401:mortality; D053208:Kaplan-Meier Estimate; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000401:mortality; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012495:San Francisco / Q000453:epidemiology; D020521:Stroke / Q000097:blood / Q000401:mortality
chemical_list: D015415:Biomarkers; D020738:Leptin