Differences in treatment, outcomes, and quality of life among patients with heart failure in Canada and the United States.

OBJECTIVES

The aim of this study was to compare clinical outcomes, resource utilization, and health-related quality of life between Canadian and U.S. patients enrolled in ASCEND-HF (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure). A further aim was to supplement the within-trial analysis with a contemporaneous population-based comparison of all patients hospitalized with primary diagnoses of heart failure (HF) in the 2 countries.

BACKGROUND

Little is known about intercountry differences in outcomes of patients with HF in Canada and the United States.

METHODS

Trial patients consisted of 465 Canadian and 2,684 U.S. patients enrolled in ASCEND-HF. Population-level cohorts consisted of 1.9 million U.S. and 81,016 Canadians hospitalized for HF in 2007 and 2008.

RESULTS

Canadian patients in ASCEND-HF were older, were more likely to be white, and had lower body weights and blood pressures than U.S. patients. Canadians also had lower baseline-adjusted odds of 30-day mortality (odds ratio: 0.46; 95% confidence interval: 0.23 to 0.92) and better health-related quality of life than U.S. patients. In both countries, trial patients differed significantly from population-level cohorts. In contrast to ASCEND-HF, unadjusted in-hospital mortality at the population level was significantly lower in the United States (3.4%) compared with Canada (11.1%) (p < 0.01).

CONCLUSIONS

Intercountry differences in outcomes of patients hospitalized with HF differed significantly between trial and population cohorts. Further study on how cardiac care is delivered in the 2 countries and how it influences the results of clinical trials and population-level outcomes, especially in the long term, is warranted. (A Study Testing the Effectiveness of Nesiritide in Patients With Acute Decompensated Heart Failure; NCT00475852).