Body mass and survival in patients with chronic heart failure without cachexia: the importance of obesity

Abstract

Background: Cachexia in chronic heart failure carries a poor prognosis, but little is known about the influence of body mass on the prognosis of noncachectic heart failure patients.

Methods: We studied 589 consecutive chronic heart failure patients followed for at least a year, in whom there were accurate baseline data for body mass.

Results: Average age was 64.5 +/- 12.4 years, left ventricular ejection fraction (LVEF) 30.9 +/- 0.73%. Cachexia was present in 64. Noncachectic patients were divided into quintiles of body mass index (BMI), Q1 (BMI 22.2 +/- 1.5) to Q5 (BMI 34.1 +/- 2.8). There was no difference among the 5 groups in age, exercise capacity or LVEF. Survival was greatest in Q4 (1-year survival [95% confidence interval (CI)]) 0.91 (0.85-0.96) and 3-year survival 0.81 (0.73-0.89). Relative risks compared with Q4 were Q1: 2.3 (1.4-3.8); Q2: 1.7 (1.1-2.9); Q3: 1.8 (1.1-3.0); and Q5: 1.5 (0.9-2.5). In multivariate analysis of 1 year follow-up, peak oxygen consumption (hazard ratio with 95% CI) (0.89 [0.82-0.97]; P =.006), LVEF (0.94 [0.91-0.97]; P =.0002) and BMI (0.90 [0.82-0.98]; P =.02) independently predicted 1-year survival with a combined Chi;(2) value of 42.4. Age (1.01 [0.98-1.05] and diagnosis (1.56 [0.78-3.11]) was not a predictor of survival.

Conclusion: In patients with chronic heart failure, increasing BMI is not an adverse prognostic feature. Thinner patients appear to have a poorer prognosis.