Association between direct measures of body composition and prognostic factors in chronic heart failure.
OBJECTIVE
To explore the covariate-adjusted associations between body composition (percent body fat and lean body mass) and prognostic factors for mortality in patients with chronic heart failure (CHF) (nutritional status, N-terminal pro-B-type natriuretic peptide [NT-proBNP], quality of life, exercise capacity, and C-reactive protein).


METHODS
Between June 2008 and July 2009, we directly measured body composition using dual energy x-ray absorptiometry in 140 patients with systolic and/or diastolic heart failure. We compared body composition and CHF prognostic factors across body fat reference ranges and body mass index (BMI) categories. Multiple linear regression models were created to examine the independent associations between body composition and CHF prognostic factors; we contrasted these with models that used BMI.


RESULTS
Use of BMI misclassified body fat status in 51 patients (41%). Body mass index was correlated with both lean body mass (r=0.72) and percent body fat (r=0.67). Lean body mass significantly increased with increasing BMI but not with percent body fat. Body mass index was significantly associated with lower NT-proBNP and lower exercise capacity. In contrast, higher percent body fat was associated with a higher serum prealbumin level, lower exercise capacity, and increased C-reactive protein level; lean body mass was inversely associated with NT-proBNP and positively associated with hand-grip strength.


CONCLUSIONS
When BMI is divided into fat and lean mass components, a higher lean body mass and/or lower fat mass is independently associated with factors that are prognostically advantageous in CHF. Body mass index may not be a good indicator of adiposity and may in fact be a better surrogate for lean body mass in this population.
Oreopoulos
Antigone
A
School of Public Health, University of Alberta, Edmonton, Alberta, Canada.
Ezekowitz
Justin A
JA
McAlister
Finlay A
FA
Kalantar-Zadeh
Kamyar
K
Fonarow
Gregg C
GC
Norris
Colleen M
CM
Johnson
Jeffery A
JA
Padwal
Raj S
RS
D015502:Absorptiometry, Photon / Q000379:methods; D000328:Adult; D000416:Alberta / Q000453:epidemiology; D000704:Analysis of Variance; D015982:Bias; D015415:Biomarkers / Q000097:blood; D001823:Body Composition; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D017079:Exercise Tolerance; D005260:Female; D018737:Hand Strength; D006333:Heart Failure / Q000097:blood / Q000209:etiology / Q000401:mortality*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D009752:Nutritional Status; D009765:Obesity / Q000145:classification / Q000150:complications / Q000175:diagnosis*; D010446:Peptide Fragments / Q000097:blood; D011228:Prealbumin / Q000378:metabolism; D011237:Predictive Value of Tests; D011379:Prognosis; D011788:Quality of Life; D012307:Risk Factors
D015415:Biomarkers; D010446:Peptide Fragments; D011228:Prealbumin; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D002097:C-Reactive Protein