Body Weight Change During and After Hospitalization for Acute Heart Failure: Patient Characteristics, Markers of Congestion, and Outcomes: Findings From the ASCEND-HF Trial

Abstract

Objectives: This study sought to examine the relationships between in-hospital and post-discharge body weight changes and outcomes among patients hospitalized for acute heart failure (AHF).

Background: Body weight changes during and after hospitalization for AHF and the relationships with outcomes have not been well characterized.

Methods: A post hoc analysis was performed of the ASCEND-HF (Acute Study of Clinical Effectiveness of Nesiritide and Decompensated Heart Failure) trial, which enrolled patients admitted for AHF regardless of ejection fraction. In-hospital body weight change was defined as the difference between baseline and discharge/day 10, whereas post-discharge body weight change was defined as the difference between discharge/day 10 and day 30. Spearman rank correlations of weight change, urine output (UOP), and dyspnea relief as assessed by a 7-point Likert scale are described. Logistic and Cox proportional hazards regression was used to evaluate the relationship between weight change and outcomes.

Results: Study participants with complete body weight data (n = 4,172) had a mean age of 65 ± 14 years, and 66% were male. Ischemic heart disease was reported in 60% of patients and the average ejection fraction was 30 ± 13%. The median change in body weight was -1.0 kg (interquartile range: -2.1 to 0.0 kg) at 24 h and -2.3 kg (interquartile range: -5.0 to -0.7 kg) by discharge/day 10. At hour 24, there was a weak correlation between change in body weight and UOP (r = -0.381), and minimal correlation between body weight change and dyspnea relief (r = -0.096). After risk adjustment, increasing body weight during hospitalization was associated with a 16% increase per kg in the likelihood of 30-day mortality or HF readmission for patients showing weight loss ≤1 kg or weight gain during hospitalization (odds ratio per kg increase 1.16, 95% confidence interval [CI]: 1.09 to 1.27; p < 0.001). Among the subset of patients experiencing >1-kg increase in body weight post-discharge, increasing body weight was associated with higher risk of 180-day mortality (hazard ratio per kg increase 1.16; 95% CI: 1.09 to 1.23; p < 0.001).

Conclusions: A substantial number of patients experienced minimal weight loss or frank weight gain in the context of an AHF trial, and increasing body weight in this subset of patients was independently associated with a worse post-discharge prognosis.

Keywords: acute heart failure; body weight; dyspnea; urine output.

Figure 1. In-Hospital Body Weight Change

The distribution of (A) absolute and (B) relative in-hospital body weight change at hour 24, discharge/day 10, and day 30.

Figure 1. In-Hospital Body Weight Change

The distribution of (A) absolute and (B) relative in-hospital body weight change at hour 24, discharge/day 10, and day 30.

Figure 2. Body Weight Change and Dyspnea

The correlation between in-hospital body weight change and dyspnea relief at 24 hours.

Figure 3. Body Weight Change and Urine Output

The correlation between in-hospital body weight change and urine output at 24 hours.

Figure 4. Urine Output and Dyspnea

The correlation between urine output and dyspnea relief at 24 hours.

Figure 5. Serum Creatinine and Change in Body Weight

Serum creatinine over time by in-hospital body weight change.

Figure 6. Blood Urea Nitrogen and Change in Body Weight

Blood urea nitrogen over time by in-hospital body weight change