Although beta-blockers can be helpful in the year following MI, they may not be helpful long-term. A large registry-based study showed event rates to be unrelated to beta-blocker use in patients post-MI. For patients with no previous MI (IHD or risk factors only), beta-blocker use was actually associated with a higher rate of revascularisation procedures and hospitalisations, with a composite outcome of cardiovascular death/nonfatal MI/non-fatal CVA being higher with beta-blocker use in the risk factors alone cohort.
However, an editorial by the professor of medical cardiology for the BHF points out the flaws in observational studies (HRT, anyone?) and adds that the findings have been contradicted by much larger observational studies (NEJM 1998; 339: 489 – 97 and JAMA 1998; 280: 623 – 9.) It seems fair to think twice about the need for beta-blockers long-term, but we probably don’t have to rush to get patients off them. Interestingly, the editorial also gave the NNT for post-MI beta-blocker therapy to be 42 to prevent one death at two years – which compares to 94 for a statin and 153 for antiplatelet therapy. (BMJ 1999; 318: 1730 – 7 and Eur Heart J 1993; 14 suppl F: 18 – 25.)
JAMA 2012; 308(13): 1340 – 9. Reported Prescriber 24(6), 19.3.13, POEMs.