Beta blockers do not lower cardiac risk in patients with or without CAD
medwireNews: Beta-blocker therapy does not reduce the risk for cardiovascular (CV) events in patients with or without coronary artery disease (CAD), researchers say.
However, further research is warranted to identify subgroups that may benefit from beta-blocker therapy and the optimal duration of therapy required for any such benefit, report Sripal Bangalore (New York University School of Medicine, New York, USA) and co-authors.
The analysis of patients from the Reduction of Atherothrombosis for Continued Health (REACH) registry revealed that the rate of the primary outcome - a composite of CV death, nonfatal myocardial infarction (MI), and nonfatal stroke - did not differ significantly between individuals with prior MI who used beta blockers and those who did not.
As reported in JAMA, there was also no difference between beta-blocker users and nonusers among CAD patients without a history of MI not.
However, 1101 (30.59%) of CAD patients without MI who used beta blockers experienced the primary composite outcome plus hospitalization for atherothrombotic events or revascularization - the secondary outcome - compared with 1002 (27.84%) of those who did not. This corresponded to a significant odds ratio (OR) of 1.14.
Moreover, 24.17% of CAD patients without MI who used beta blockers experienced MI or stroke compared with 21.48%, who did not corresponding to a significant OR of 1.17.
The event rate for the primary outcome in individuals with CAD risk factors only was also significantly higher in those who used beta blockers, at 467 (14.22%) than those who did not, at 403 (12.11%), corresponding to a hazard ratio of 1.18.
The secondary outcome occurred significantly more frequently in the beta-blocker users in this cohort, at 870 (22.01%) versus 797 (20.17%), corresponding to an OR of 1.12. However, there was no difference in occurrence of the tertiary outcome (defined as all-cause mortality, cardiovascular mortality, nonfatal MI, nonfatal stroke, and hospitalization) between the two groups.
Analysis of individuals who had experienced MI within the past year and used beta blockers revealed that they experienced a lower incidence of the secondary outcome and of hospitalization, at an OR of 0.77 for both. However, there was no significant association for the primary outcome.
The authors say that their findings are consistent with American Heart Association secondary prevention guidelines in which beta-blocker therapy is a class I recommendation for heart failure, MI, or acute coronary syndrome for up to 3 years after MI.
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By Piriya Mahendra, medwireNews Reporter