Pharmacological treatment of congestive heart failure in Canada: A description of care in five provinces

Introduction: Congestive heart failure (CHF) is responsible for significant morbidity, mortality and health resource consumption. There have been major advances in the treatment of this condition over the past two decades, yet little information is currently available regarding the current status of CHF management in Canada. Objective: To describe the pharmacological management of patients hospitalized with CHF in five provinces: Alberta, British Columbia, Nova Scotia, Ontario and Quebec. Design and methods: Administrative data sources were used to identify all consecutive patients hospitalized with a principal diagnosis of CHF and discharged alive in the provinces of Alberta, British Columbia, Quebec and Ontario. Rates of use of prespecified medications at 30 days after hospital discharge were obtained for patients 65 years of age and older by linkage of their hospital records with drug benefit plans in these provinces. For Nova Scotia, the disease-specific registry of the Improving Cardiovascular Outcomes in Nova Scotia (ICONS) study was used to obtain discharge medications of individuals consecutively hospitalized with a diagnosis of CHF. Where available, data were acquired from 1997 to 2002. Results: Data were obtained for a total of 115,037 patients in the five provinces over the five-year period. Overall, 54.9% of patients received an angiotensin-converting enzyme inhibitor at or 30 days after hospital discharge, with minimal change in prescription rates over the five-year period. Beta-blocker prescription rates increased steadily during the study, more than doubling from 15.0% in 1997/1998 to 32.0% in 2001/2002. Spironolactone use increased dramatically, with only 2.2% of patients receiving this medication in 1997/1998 compared with 18.7% in 2001/2002. The rates of digoxin prescription decreased each year, while the use of angiotensin receptor blockers increased slightly throughout the observation period. Conclusions: While the use of evidence-based treatment for CHF in Canada is increasing and is currently at levels similar to those reported in other developed countries, there is still the potential in every province for further improvement.