Related Experiment Videos
[Incidence and timing of thyroid dysfunction with long-term amiodarone therapy]
F Rouleau1, O Baudusseau, J M Dupuis
1Service de cardiologie, CHU d'Angers, rue Larrey, 49000 Angers.
Archives Des Maladies Du Coeur Et Des Vaisseaux
|March 10, 2001
Summary
Long-term amiodarone therapy can cause thyroid dysfunction in nearly 20% of patients. Hyperthyroidism is more common than hypothyroidism and may worsen over time, potentially linked to cumulative amiodarone dosage.
Area of Science:
- Cardiology
- Endocrinology
- Pharmacology
Context:
- Amiodarone is a widely used antiarrhythmic drug for atrial fibrillation.
- Long-term amiodarone treatment is associated with various adverse effects.
- Thyroid dysfunction is a known complication of amiodarone therapy due to its high iodine content.
Purpose:
- To investigate the incidence, timing, and clinical presentation of thyroid dysfunction in patients on long-term amiodarone.
- To differentiate between hypothyroidism and hyperthyroidism in this patient cohort.
- To explore potential relationships between amiodarone dosage, treatment duration, and thyroid dysfunction.
Summary:
- This retrospective study analyzed 90 patients on long-term amiodarone (200 mg daily) for a mean of 33 months.
- Hypothyroidism occurred in 5.5% of patients with minimal symptoms.
- Hyperthyroidism was more frequent (12.2%), often symptomatic with arrhythmias, and showed an increasing incidence over time, suggesting a dose-dependent effect.
Impact:
- Nearly 1 in 5 patients on long-term amiodarone experience thyroid side effects.
- Hyperthyroidism is more prevalent and appears to correlate with cumulative amiodarone exposure.
- Findings highlight the importance of monitoring thyroid function in patients receiving amiodarone therapy.