DAILY ENERGY-EXPENDITURE IN FREE-LIVING HEART-FAILURE PATIENTS

We examined the hypothesis that weight loss in heart failure patients is associated with elevated daily energy expenditure. Twelve cachectic patients [age = 73 +/- 6 yr; weight loss = 15 +/- 6 kg; body mass ind ex (BMI) = 21 +/- 5 kg/m(2)], 13 noncachectic patients (age = 67 +/- 5 yr; BMI = 27 +/- 5 kg/m(2)), and 50 healthy elderly controls (age = 6 9 +/- 6 yr; BMI = 26 +/- 4 kg/m(2)) were studied. Daily energy expendi ture and it components were measured using doubly labeled water and in direct calorimetry and body composition by dual-energy X-ray absorptio metry. Fat mass and fat-free mass were lower (P < 0.05) in cachectic p atients compared with noncachectic patients and healthy controls. Dail y energy expenditure was lower (P < 0.05) in cachectic patients (1,870 +/- 347 kcal/day) compared with noncachectic patients (2,349 +/- 545 kcal/day) and healthy controls (2,543 +/- 449 kcal/day). Differences i n daily energy expenditure were primarily due to lower (P < 0.05) phys ical activity energy expenditure in cachectic (269 +/- 307 kcal/day) a nd noncachectic patients (416 +/- 361 kcal/day) compared with healthy controls (728 +/- 374 kcal/day). A lower (P < 0.05) resting energy exp enditure was also noted in cachectic patients (1,414 +/- 210 kcal/day) compared with noncachectic patients (1,698 +/- 252 kcal/day) and heal thy controls (1,561 +/- 223 kcal/day). These findings show that daily energy expenditure is not higher, but significantly lower, in cachecti c heart failure patients due to lower physical activity and resting en ergy expenditure. These results argue against the hypothesis that an a bnormally elevated daily energy expenditure is associated with weight loss in heart failure.