The obesity paradox: body mass index and outcomes in patients with heart failure.
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.
Curtis
Jeptha P
JP
Department of Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT 06520-8088, USA.
Selter
Jared G
JG
Wang
Yongfei
Y
Rathore
Saif S
SS
Jovin
Ion S
IS
Jadbabaie
Farid
F
Kosiborod
Mikhail
M
Portnay
Edward L
EL
Sokol
Seth I
SI
Bader
Feras
F
Krumholz
Harlan M
HM
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