Prevalence, Profile, and Prognosis of Severe Obesity in Contemporary Hospitalized Heart Failure Trial Populations

Abstract

Objectives: This study evaluated the prevalence, profile, and prognosis of severe obesity in a large contemporary acute heart failure (AHF) population.

Background: Better prognosis has been reported for obese heart failure (HF) patients than nonobese HF patients, but in other cardiovascular populations, this effect has not been demonstrated for severely obese patients.

Methods: A cohort of 795 participants with body mass index (BMI) measured at time of admission and complete follow-up were identified from enrollment in 3 contemporary AHF trials (DOSE [Diuretic Strategies Optimization Evaluation], CARRESS-HF [Cardiorenal Rescue Study in Acute Decompensated Heart Failure], and ROSE [Renal Optimization Strategies Evaluation in Acute Heart Failure]). Patients were divided into 4 BMI categories according to standard World Health Organization criteria, as follows: normal weight: 18.5 to 25 kg/m² [n = 128]; overweight: 25 to 29.9 kg/m² [n = 209]; mild-to-moderate obese: 30 to 39.9 kg/m² [n = 301]; and severely obese: ≥40 kg/m² [n = 157]). The relationship between BMI and 60-day composite outcome (death, rehospitalization, or unscheduled provider visit) was investigated.

Results: Patients with severe obesity (19.7%) were younger, more often female, hypertensive, diabetic, and more likely to have higher blood pressures and left ventricular ejection fraction, and lower N-terminal pro-B-type natriuretic peptide and troponin I levels than other BMI category patients. Following admission for AHF, patients with normal weight showed the highest risk of 60-day composite outcome, followed by patients who were severely obese. Overweight and mild-moderately obese patients showed lowest risk.

Conclusions: Nearly one-fifth of AHF patients enrolled in contemporary randomized clinical trials are severely obese. A U-shaped curve for short-term prognosis according to BMI is seen in AHF. These findings may help to better inform both HF clinical care and future clinical trial planning.

Keywords: acute decompensated heart failure; obesity; prognosis; severe obesity.

Figure 1.

The CONSORT Diagram Illustrating Study Cohort Selection BMI = body mass index; CARRESS-AHF = Cardiorenal Rescue Study in Acute Heart Failure; CONSORT = Consolidated Standards of Reporting Trials; DOSE-AHF = Diuretic Strategies Optimization Evaluation in Acute Heart Failure; ROSE-AHF = Renal Optimization Strategies in Evaluation in Acute Heart Failure.

Figure 2.

Relationship Between BMI and NT-proBNP in Acute Heart Failure Graph of the log2 transformed NT-proBNP versus BMI showing an approximately linear relationship. Spearman’s correlation coefficient = −0.47 (p < 0.0001). NT-proBNP = N-terminal pro–B-type natriuretic peptide; other abbreviation as in Figure 1.

Figure 3.

Predicted 60-Day Primary Composite Event Rates Predicted rates for the primary composite endpoint of death, rehospitalization, or unscheduled provider visit at 60 days (N = 353 events). A U-shaped relationship is demonstrated between BMI and short-term adverse events in the AHF population. AHF = acute heart failure; other abbreviation as in Figure 1.

Figure 4.

Forest Plots Show Relationship Between Subgroups and Composite Endpoint According to BMI category Forest plots show relationship between relevant subgroups (age, sex, LVEF <50% vs ≥50%, ischemia cause, presence of diabetes or hypertension) and the composite endpoint according to BMI category (<30, 30–40, >40 kg/m2), with BMI <30 kg/m2 serving as the reference group. Markers to the left of 1 indicate whether patients in that particular BMI category have a lower risk of composite endpoint than those with BMI <30 kg/m2. Interaction p values are shown. The only subgroup that showed a relationship different from that of the composite endpoint according to BMI category was ischemia versus nonischemia cause. LVEF = left ventricular ejection fraction; other abbreviation as in Figure 1.