Use of ezetimibe in the United States and Canada

Background: Ezetimibe lowers low-density lipoprotein cholesterol, but current lipid-lowering guidelines in the United States and Canada do not recommend it as a first option for either primary or secondary prevention. We sought to describe the adoption of ezetimibe relative to that of other lipid-lowering agents and compare its use in the two countries. Methods: We conducted a population-level, cohort study using data from January 2002 to December 2006, provided by IMS Health, to describe prescribing practices and expenditures for lipid-lowering agents and ezetimibe in the United States and Canada. Results: From 2002 to 2006, the monthly number of prescriptions for lipid-lowering agents rose from 3719 to 7401 per 100,000 population in Canada and from 3927 to 6827 per 100,000 population in the United States. Of these prescriptions, the proportion for ezetimibe rose from 0.2% in 2003 to 3.4% in 2006 in Canada and from 0.1% in 2002 to 15.2% in 2006 in the United States. Statin use was relatively constant between 2002 and 2006 in Canada, whereas the proportion of statin prescriptions decreased from 86.5 to 80.8% in the United States. In 2006, the ratio of prescriptions for statins to those for ezetimibe was 26:1 in Canada and 5:1 in the United States. In 2006, expenditures for ezetimibe per 100,000 population were higher in the United States than in Canada by a factor of more than 4. Conclusions: Distinct patterns of use of ezetimibe emerged in the United States and Canada from 2002 to 2006, a difference that markedly altered the approach to the treatment of hyperlipidemia in the United States. The U.S. pattern increased overall costs, but the effect on clinical outcomes is uncertain. N Engl J Med 2008;358:1819-28.