title: Effect of obesity and being overweight on long-term mortality in congestive heart failure: influence of left ventricular systolic function.
abstract: OBJECTIVE
  Previous studies have suggested that a high body mass index (BMI) is associated with an improved outcome in congestive heart failure (CHF). However, the studies addressing this problem have not included enough patients with non-systolic heart failure to evaluate how left ventricular systolic function interacts with obesity on prognosis in CHF. The aim of this study was to evaluate how BMI influences mortality in patients hospitalized with CHF, and to address in particular whether the effect of BMI is influenced by left ventricular (LV) systolic function.
  
  
  RESULTS
  Retrospective analysis of baseline and survival data for 4700 hospitalized CHF patients for whom BMI was available. LV systolic function, as assessed by wall motion index was available for 95% of the patients. Follow-up time ranged from 5 to 8 years. In the total population, the risk of death decreased steadily with increasing BMI from the underweight to the obese. Compared with normal weight, and adjusted for sex and age, risk ratios (RR) and 95% confidence limits were: underweight 1.56 (1.33-1.84), overweight 0.90 (0.83-0.97), obese 0.77 (0.70-0.86). Being underweight conferred a greater risk in CHF patients with normal systolic function [RR 1.66 (1.29-2.14), compared with normal weight] than in patients with reduced systolic function [RR 1.11 (0.87-1.42), P for interaction 0.03]. In patients with systolic dysfunction, obesity was associated with increased risk compared with normal weight [RR 1.21 (1.01-1.45)].
  
  
  CONCLUSIONS
  Increasing BMI in CHF is associated with a lower mortality, but the influence is complex and depends on left ventricular systolic function. Hence, in patients with systolic dysfunction obesity may indicate an increased risk.
authors.affiliation: Department of Cardiology B, The Heart Centre 2142, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen Ø, Denmark. finng@dadlnet.dk
authors.forename: Finn
authors.initials: F
authors.lastname: Gustafsson
authors.forename: Charlotte B
authors.initials: CB
authors.lastname: Kragelund
authors.forename: Christian
authors.initials: C
authors.lastname: Torp-Pedersen
authors.forename: Marie
authors.initials: M
authors.lastname: Seibaek
authors.forename: Hans
authors.initials: H
authors.lastname: Burchardt
authors.forename: Dilek
authors.initials: D
authors.lastname: Akkan
authors.forename: Jens Jakob
authors.initials: JJ
authors.lastname: Thune
authors.forename: Lars
authors.initials: L
authors.lastname: Køber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D005260:Female; D006333:Heart Failure / Q000209:etiology / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000401:mortality*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000401:mortality*