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Study highlights important differences in heart failure care between the U.S. and Ontario


A new study from the Institute for Clinical Evaluative Sciences (ICES) demonstrates significant differences in the care provided to elderly heart failure patients hospitalized in Ontario versus the United States.

“Heart failure is an important condition to study because it affects millions of Canadians and Americans, and the long-term outcomes of heart failure patients are extremely poor, with one-year mortality rates after hospitalization estimated to be 25% to 40%,” said study lead author and ICES research fellow Dr. Dennis Ko. “As well, evaluating the processes of care and outcomes of heart failure patients treated in both countries may provide insights about the relative performance of these two health systems.”

To conduct the study, ICES scientists partnered with colleagues from the U.S. to compare processes of care, and 30-day and one-year mortality rates among 28,521 U.S. Medicare beneficiaries and 8,180 similarly aged Ontario patients hospitalized with heart failure between 1998 and 2001.


  • More U.S. heart failure patients than Ontario heart failure patients underwent left ventricular ejection fraction (LVEF) assessment (to evaluate how well the heart is pumping) during hospitalization (61.2% vs. 41.7%).
  • The use of medications, such as beta-blockers and angiotensin-converting enzyme (ACE) inhibitors, at hospital discharge was not substantially different between the two groups.
  • The 30-day mortality rate was significantly lower for U.S. patients (8.9% vs. 10.7%), but the one-year mortality rate was not different (32.2% vs. 32.3%).
  • Heart failure patients hospitalized in Ontario were sicker than U.S. patients.

“There are a variety of possible explanations for our results,” said Dr. Ko.

“Ontario hospitals are smaller and have less invasive cardiac facilities, which could explain the lower use of LVEF. As well, Ontario physicians may not hospitalize some lower-risk patients, who would have been hospitalized in the U.S., because of our smaller hospital sizes and bed availability – something that could contribute to Ontario patients being sicker when they are hospitalized, as shown in our study.

“However, despite these limitations in Ontario, we did not observe substantial differences in the overall use of life-saving therapies, such as beta-blockers and ACE inhibitors,” said Dr. Ko.

Dr. Ko also points out that a more aggressive approach to care has been repeatedly demonstrated in patients with cardiovascular disease treated in the U.S. “This intensity of hospital care in the U.S. could explain the better short-term mortality rates in U.S. heart failure patients, while the similar long-term mortality rates between Ontario and the U.S. may reflect better access in Ontario to outpatient follow-up and prescription drugs.

“Nevertheless, further studies are needed to explore the reasons underlying these differences in outcomes and to gain additional insights to improve the care and outcomes of heart failure patients in both countries,” Dr. Ko said.

The study, “Quality of care and outcomes of older heart failure patients hospitalized in the United States and Canada”, is in the November 28, 2005 issue of the Archives of Internal Medicine.

Author affiliations: ICES (Drs. Ko, Tu and Lee, Ms. Newman, and Ms. Donovan); Department of Cardiology, Schulich Heart Centre (Dr. Ko), Department of Internal Medicine (Dr. Tu), Sunnybrook and Women’s College Health Sciences Centre; Department of Medicine, Denver Health Medical Center (Drs. Masoudi and Havranek); Department of Medicine, University of Colorado Health Sciences Centre (Drs. Masoudi and Havranek); Section of Cardiovascular Medicine, Department of Medicine, Yale University School of Medicine (Drs. Foody and Krumholz, Ms. Wang, and Mr. Rathore); Section of Health Policy and Administration, Department of Epidemiology and Public Health, Robert Wood Johnson Clinical Scholars Program, Yale University School of Medicine, and the Center for Outcomes Research and Evaluation, Yale-New Haven Health (Dr. Krumholz).

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.


  • Julie Argles
  • Media Relations Officer, ICES
  • (416) 480-4780 or cell (416) 432-8143


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