Why are beta blockers (beta-adrenergic blocking agents) not recommended in patients without a history of Myocardial Infarction (MI) and are they beneficial in the geriatric population?

From the Guidelines

Beta blockers are not recommended for patients without a history of Myocardial Infarction (MI) due to their unfavorable risk-benefit ratio in this population. The evidence suggests that beta blockers offer limited cardiovascular protection in primary prevention, while potentially causing significant side effects such as fatigue, sexual dysfunction, and worsening of respiratory conditions like asthma or COPD 1.

Key Considerations

• In geriatric patients, beta blockers should be used with caution due to the increased risk of adverse effects such as orthostatic hypotension, falls, bradycardia, and cognitive impairment 1.
• When beta blockers are necessary in elderly patients, it is advisable to start with lower doses (e.g., metoprolol 12.5-25mg twice daily instead of 50mg, or carvedilol 3.125mg twice daily instead of 6.25mg) and titrate slowly while monitoring for side effects 1.
• Beta-selective agents like metoprolol are often preferred in older adults to minimize respiratory and metabolic complications.

Benefits and Risks

• The benefits of beta blockers are well established in patients with a history of MI, heart failure with reduced ejection fraction, or certain arrhythmias, where their benefits clearly outweigh their risks 1.
• However, in patients without these conditions, the risks of beta blockers may outweigh their benefits, and alternative treatments should be considered 1.

Clinical Decision-Making

• The decision to use beta blockers in any patient, especially geriatric ones, should be individualized based on specific indications and careful consideration of the potential benefits and risks 1.
• Clinicians should weigh the potential benefits of beta blockers against the potential risks and consider alternative treatments that may be more effective and safer for the patient.

From the FDA Drug Label

Of the 975 myocardial infarction patients randomized to Carvedilol Tablet in the CAPRICORN trial, 48% (468) were 65 years of age or older, and 11% (111) were 75 years of age or older. With the exception of dizziness in hypertensive patients (incidence 8. 8% in the elderly versus 6% in younger patients), no overall differences in the safety or effectiveness were observed between the older subjects and younger subjects in each of these populations In worldwide clinical trials of metoprolol tartrate in myocardial infarction, where approximately 478 patients were over 65 years of age (0 over 75 years of age), no age-related differences in safety and effectiveness were found

Beta blockers are not recommended in patients without a history of Myocardial Infarction (MI) because there is no direct information in the provided drug labels that supports their use in this population. In the geriatric population, beta blockers may be beneficial, as there were no overall differences in safety or effectiveness observed between older and younger subjects in clinical trials of carvedilol and metoprolol 2 3. However, dosing should proceed with caution in this population due to the potential for greater sensitivity of some elderly individuals.

• Key points:
  • No direct information supports the use of beta blockers in patients without a history of MI
  • Beta blockers may be beneficial in the geriatric population
  • Dosing should proceed with caution in elderly individuals due to potential greater sensitivity

From the Research

Beta Blockers in Patients Without a History of Myocardial Infarction

• Beta blockers are not recommended in patients without a history of myocardial infarction (MI) as the benefits of beta blockers in this population are unclear 4.
• A systematic review of 25 trials found that beta blockers probably reduce the risks of all-cause mortality and myocardial reinfarction in patients younger than 75 years of age without heart failure following acute myocardial infarction, but the evidence is of moderate to low certainty 4.
• The review also found that beta blockers may reduce the risks of major cardiovascular events and cardiovascular mortality compared with placebo or no intervention in patients younger than 75 years of age without heart failure following acute myocardial infarction, but the effects could be driven by patients with unrecognised heart failure 4.

Beta Blockers in the Geriatric Population

• The effects of beta blockers on patients 75 years of age and older are unclear due to limited data 4, 5.
• A study found that beta blockers are a highly effective treatment for patients with all grades of heart failure secondary to LV systolic dysfunction, but the benefits of beta blockers in patients over 80 years of age are still being researched 5.
• Factors predisposing the older person with acute myocardial infarction to develop heart failure include an increased prevalence of MI, multivessel coronary artery disease, and decreased left ventricular contractile reserve, among others 6.
• Guidelines recommend that post-MI patients should be started on beta-blocker therapy and continued indefinitely, unless absolutely contraindicated or not tolerated, but the practical implementation of beta blockers in the geriatric population requires careful consideration 7.