Angiotensin receptor blockers (ARBs)

Guertin and colleagues describe potential savings from restricting use of ARBs in Canada.1 The US Department of Veterans Affairs prefers angiotensin-converting-enzyme (ACE) inhibitors over ARBs, with national criteria for use to guide prescribing.

Even in a closed system such as Veterans Affairs, however, there are opportunities for savings; we find substantial variation in the use of ARBs and ACE inhibitors across the system. For 2009, we examined variations among facilities in the proportion of patients taking a renin-angiotensin system blocker who were also taking an ARB.2 The median proportion was 17.2% (lower than the 25% described by Guertin and colleagues for 2006) but ranged across facilities from 6.4% to 33.6%. In an analysis in fiscal year 2010, we found that if all regions in Veterans Affairs were to use ARBs at a rate not higher than the national average, the savings to the department could be US$2.4 million per year (unpublished data). If all facilities were to use ARBs at a rate not higher than the lowest-using five facilities, the savings would have been US$6.5 million per year.

We concur with the authors that careful evaluation of patterns of drug use can identify opportunities for substantial cost savings, where patient outcomes are not likely to be adversely affected. Such variation in precribing patterns suggests that factors beyond patient variability affect drug choice. Even small differences in patterns of use can have large cost implications at a national level, as the authors demonstrated for just one drug class in Canada.