title: The obesity paradox: body mass index and outcomes in patients with heart failure.
abstract: BACKGROUND
  In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF).
  
  
  METHODS
  We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months.
  
  
  RESULTS
  Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53).
  
  
  CONCLUSIONS
  In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.
authors.affiliation: Department of Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT 06520-8088, USA.
authors.forename: Jeptha P
authors.initials: JP
authors.lastname: Curtis
authors.forename: Jared G
authors.initials: JG
authors.lastname: Selter
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Wang
authors.forename: Saif S
authors.initials: SS
authors.lastname: Rathore
authors.forename: Ion S
authors.initials: IS
authors.lastname: Jovin
authors.forename: Farid
authors.initials: F
authors.lastname: Jadbabaie
authors.forename: Mikhail
authors.initials: M
authors.lastname: Kosiborod
authors.forename: Edward L
authors.initials: EL
authors.lastname: Portnay
authors.forename: Seth I
authors.initials: SI
authors.lastname: Sokol
authors.forename: Feras
authors.initials: F
authors.lastname: Bader
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D000368:Aged; D015992:Body Mass Index; D002986:Clinical Trials as Topic; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications* / Q000188:drug therapy / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications* / Q000401:mortality*; D010045:Outpatients; D016016:Proportional Hazards Models