Lower doses are as effective or more effective than higher doses of beta-blockers for the survival of patients following acute myocardial infarction, according to a study published online September 21 in the Journal of the American College of Cardiology.
Jeffrey J. Goldberger, MD, MBA, and fellow investigators found that patients who received a quarter of a high dose of beta-blockers that has been used in previous clinical trials demonstrated decreases in mortality that were as high as 20% to 25%, when compared with patients who received the full dose.
The researchers analyzed data in a multicenter registry on 6,682 patients who had had an acute myocardial infarction; median follow-up for these patients was 2.1 years and 90% were receiving beta-blockers. Patients in the study who took beta-blockers, regardless of dose, survived longer, compared with patients who did not receive beta-blockers. The researchers found that within 2 years, death occurred in 14.7% of patients who received the full dose of beta-blockers, 12.9% of those receiving half of that dose, 9.5% of those receiving a quarter of the dose, and 11.5% of those receiving an eighth of the dose.
In addition, beta-blockers have side effects, including fatigue, sexual dysfunction, and depression, which would make prescribing lower doses to patients following a heart attack a more attractive option.
More research is necessary to determine what doses are most effective for different populations, Dr. Goldberger said. “There is probably not one right dose for every single patient,” he said. “It doesn’t make sense that the same dose will work for an 80-year-old frail man who had a small heart attack as a burly 40-year-old man with a huge heart attack.”