title: The obesity-mortality paradox in elderly patients with angiographic coronary artery disease: a report from the ET-CHD registry.
abstract: BACKGROUND
  The body mass index (BMI)-mortality paradox has been well known in patients with obstructive coronary artery disease (CAD). However, this phenomenon has rarely been described among elderly patients over a 5-year follow-up.
  
  
  METHODS
  We studied a cohort of 722 elderly patients (age 65 years) with angiographic CAD from the ET-CH D registry during 1997-2003 in eastern Taiwan. To evaluate the BMI effect on mortality, the elderly subjects were categorized into 5 groups by BMI (kg/m2): underweight and normal-low weight (< 21), normal-high weight (21-23.9) overweight (24-26.9), mild obesity (27-29.9) and moderate/severe obesity (30). At a maximal 10-year follow-up, cardiac and all-cause deaths were the primary end points.
  
  
  RESULTS
  After multivariate analysis, patients from the category of under weight and normal-low weight in reference to those from the normal-high weight category had a significantly higher risk of cardiac and all-cause mortality (hazard ratio (HR): 1.68 (95% CI: 1.04-2.70) and 2.02 (95% CI: 1.42-2.87), respectively) following a median of 5.4 years. Obese elderly patients tended to have the lowest risk of all-cause death across all the study BMI categories in the early stage. However, after 5 years, mortality increased in the obese patients surviving beyond 5 years, and was higher than that in overweight patients.
  
  
  CONCLUSIONS
  The obesity-mortality paradox was present in elderly patients with angiographic CAD in Taiwan and the risk of death was significantly higher in those with a BMI < 21 kg/n2. However, a J-shaped relationship between mortality and BMI developed after 5 years of follow-up.
authors.forename: Gen-Min
authors.initials: GM
authors.lastname: Lin
authors.forename: Yi-Hwei
authors.initials: YH
authors.lastname: Li
authors.forename: Cha-Po
authors.initials: CP
authors.lastname: Lai
authors.forename: Chin-Lon
authors.initials: CL
authors.lastname: Lin
authors.forename: Ji-Hung
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000368:Aged; D015992:Body Mass Index; D002423:Cause of Death; D015331:Cohort Studies; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D009026:Mortality / Q000639:trends; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications / Q000175:diagnosis / Q000401:mortality; D012042:Registries; D012307:Risk Factors; D012720:Severity of Illness Index; D013624:Taiwan / Q000453:epidemiology; D013997:Time Factors