Amiodarone-Associated Myxedema Coma

Area of Science:

• Endocrinology
• Cardiology
• Geriatrics

Background:

• Myxedema coma is a rare but life-threatening endocrine emergency with high mortality rates.
• Altered mental status in older adults has a broad differential diagnosis, often obscuring less common causes like hypothyroidism.
• Amiodarone, a common medication for atrial fibrillation, is known to affect thyroid function.

Observation:

• A 71-year-old male on long-term amiodarone presented with altered mental status.
• Initial assessments attributed symptoms to uremia, hyponatremia, and pneumonia.
• Persistent altered mental status prompted further investigation.

Findings:

• Thyroid function tests revealed a significantly elevated thyroid-stimulating hormone (TSH) level of 89 μIU/mL.
• The patient met the clinical criteria for myxedema coma.
• This diagnosis was made after initial presentations were attributed to other common conditions.

Implications:

• Thyroid function tests should be considered in the diagnostic workup of encephalopathic older adults, particularly those on amiodarone.
• Early recognition and treatment of myxedema coma are crucial for improving patient outcomes.
• This case highlights the importance of considering drug-induced thyroid dysfunction in complex geriatric presentations.