Ramipril use in Canada: HOPE or HYPE?

were developed for the treatment of hypertension. Subsequently they became indicated for several cardiovascular and renal conditions. ACE inhibitors play several roles: they alter the balance between the vasoconstrictive, salt-retentive and hypertrophic properties of angiotensin II, and they interfere with the vasodilatory and natriuretic effects of bradykinin and with the metabolism of other vasoactive substances. ACE inhibitors have different chemical structures. As a result, they differ in potency, bioavailability, plasma halflife, route of elimination, distribution and affinity for tissue-bound ACE. Thus, their structural heterogeneity may reflect their functional heterogeneity. In this issue (page 553), Tu and colleagues report that after release of the results of the Heart Outcomes Prevention Evaluation (HOPE) the monthly rate of new prescriptions for the ACE inhibitor ramipril filled by elderly (aged 65 and over) residents of Ontario rose more than 400%. Similar patterns were seen in most Canadian provinces (Cynthia Jackevicius, Institute for Clinical Evaluative Sciences, Toronto, Ont.): personal communication, 2002). The monthly number of new prescriptions for all ACE inhibitors rose from 382/100 000 before the first formal release of the HOPE findings to 551/100 000 9 months later. The technique of time-series analysis took into account baseline temporal changes. These striking results raise two important issues. First, is the extensive use of ramipril over other ACE inhibitors appropriate? Second, what factors led to the increase in ramipril prescription? ACE inhibitors have been shown to be effective in treating essential hypertension, renal disease and congestive heart failure, as well as in improving survival after acute myocardial infarction. Although beneficial effects may occur with all drugs in this class, the extent to which they occur may vary. In most trials of ACE inhibitor therapy for patients with congestive heart failure, acute myocardial infarction or diabetes mellitus, ramipril was not the main ACE inhibitor studRamipril use in Canada: HOPE or HYPE?