Patterns of weight change preceding hospitalization for heart failure

Abstract

Background: Weight gain is used by disease-management programs as a marker of heart failure decompensation, but little information is available to quantify the relationship between weight change in patients with heart failure and the risk for imminent hospitalization.

Methods and results: We conducted a nested case-control study among patients with heart failure referred to a home monitoring system by managed care organizations. We matched 134 case patients with heart failure hospitalization to 134 control patients without heart failure hospitalization on the basis of age, sex, duration of home monitoring, heart failure severity, and baseline body weight. Compared with control patients, case patients experienced gradual weight gain beginning approximately 30 days before hospitalization; changes in daily weight between case and control patients were statistically significant (P<0.001). Within the week before hospitalization, when weight patterns in case and control patients began to diverge more substantially, mean increases of more than 2 and up to 5 pounds, more than 5 and up to 10 pounds, and more than 10 pounds (relative to time of enrollment in the monitoring system) were associated with matched adjusted odds ratios for heart failure hospitalization of 2.77 (95% confidence interval 1.13 to 6.80), 4.46 (95% confidence interval 1.45 to 13.75), and 7.65 (95% confidence interval 2.22 to 26.39), respectively, compared with mean increases of 2 pounds or less.

Conclusions: Increases in body weight are associated with hospitalization for heart failure and begin at least 1 week before admission. Daily information about patients' body weight identifies a high-risk period during which interventions to avert decompensated heart failure that necessitates hospitalization may be beneficial.

Conflict of interest statement

Disclosures: Alere Medical Inc provided the data but had no role in the design and conduct of the study; management, analysis, and interpretation of the data; or preparation, review, or approval of the manuscript. Dr Krumholz serves on the Advisory Board for Alere Medical Inc but does not have equity in the company. Dr Krumholz has research contracts with the Colorado Foundation for Medical Care and the American College of Cardiology, serves on the advisory boards for Amgen and UnitedHealthcare, is a subject matter expert for VHA, Inc, and is editor-in-chief of Journal Watch Cardiology of the Massachusetts Medical Society. The remaining authors report no conflicts.

Figures

Figure 1

Daily weight change before heart failure hospitalization: cases vs controls. n=268. “Days” on the x-axis denotes days before hospital admission in case patients. The difference in daily weight changes between case and control patients within 30 days before (case) hospitalization was statistically significant (P<0.001) on the basis of a generalized linear model with daily weight change as the dependent variable.

Figure 2

Daily weight change before non–heart failure hospitalization: cases vs controls. n=1376. “Days” on the x-axis denotes days before hospital admission in case patients.