Would loop diuretics be indicated in a 92-year-old male with elevated N-terminal pro b-type natriuretic peptide (NT-proBNP) levels, on Kerendia (finerenone), without overt signs of volume overload?

Loop Diuretics in an Elderly Patient with Elevated NT-proBNP Without Overt Volume Overload

Loop diuretics are not indicated for a 92-year-old male with persistently elevated NT-proBNP (4000) on Kerendia (finerenone) who has no overt signs of volume overload.

Rationale for Not Using Loop Diuretics

Understanding the Clinical Context

• The patient is elderly (92 years old) with elevated NT-proBNP levels (4000)
• Currently on Kerendia (finerenone), which is a non-steroidal mineralocorticoid receptor antagonist
• No overt signs of volume overload are present
• NT-proBNP elevation without clinical volume overload may reflect:
  • Age-related changes in cardiac function
  • Renal impairment (common in elderly patients)
  • Effects of underlying cardiac disease rather than fluid overload

Evidence-Based Approach

According to guidelines, loop diuretics should primarily be used when there is evidence of fluid retention:

1. Guideline Recommendations:

   • The ACC/AHA guidelines state that "patients with evidence of fluid retention should take a diuretic until a euvolemic state is achieved" 1
   • Diuretics should be "continued to prevent the recurrence of fluid retention" 1
   • Current guidelines emphasize that loop diuretics are indicated for "relief of acute fluid overload" 1

2. Absence of Clinical Indications:

   • Loop diuretics are primarily indicated for treating fluid retention and edema
   • Without overt signs of volume overload, initiating loop diuretics may lead to:
     • Dehydration
     • Electrolyte abnormalities
     • Worsening renal function
     • Hypotension (particularly concerning in the elderly)

3. Risks in Elderly Patients:

   • The FDA label for furosemide warns that "excessive diuresis may cause dehydration and blood volume reduction with circulatory collapse and possibly vascular thrombosis and embolism, particularly in elderly patients" 2
   • Elderly patients are more susceptible to adverse effects of diuretics including:
     • Electrolyte disturbances (hyponatremia, hypokalemia)
     • Dehydration
     • Orthostatic hypotension
     • Acute kidney injury

Monitoring and Alternative Approaches

Monitoring Strategy

• Regular clinical assessment for subtle signs of volume overload:
  • Weight changes
  • Respiratory status
  • Peripheral edema
  • Jugular venous distension
• Serial NT-proBNP measurements to track trends
• Renal function and electrolyte monitoring

Alternative Considerations

1. Optimize Current Therapy:

   • Ensure optimal dosing of Kerendia
   • Review and optimize other heart failure medications if applicable

2. Consider Underlying Causes:

   • Evaluate for other causes of elevated NT-proBNP:
     • Chronic kidney disease
     • Atrial fibrillation
     • Age-related cardiac changes
     • Subclinical heart failure

3. When to Reconsider Diuretics:

   • If clinical signs of volume overload develop
   • If NT-proBNP continues to rise significantly
   • If symptoms of heart failure emerge

Conclusion

In this 92-year-old patient with elevated NT-proBNP but no overt signs of volume overload, initiating loop diuretics is not indicated and may cause harm. The risks of adverse effects in elderly patients outweigh potential benefits when clinical volume overload is absent. Continue monitoring for signs of volume overload and consider diuretics only if clinical evidence of fluid retention develops.