Amiodarone-associated thyroid dysfunction: risk factors in adults with congenital heart disease.

Abstract

BACKGROUND:

Amiodarone is widely used in adults with congenital heart disease, but no systematic study has been published on its effects on thyroid function in these patients. A retrospective study was performed to examine the frequency of amiodarone-associated thyroid dysfunction in adults with congenital heart disease and to identify any contributing factors.

METHODS AND RESULTS:

All adults (16 to 60 years old) with congenital heart disease were identified from a database if they had no preexisting thyroid disease, had taken amiodarone for >/=6 months, and were currently followed up by 1 consultant (J.S.). Ninety-two patients were found and evaluated for thyroid status and cardiac complications. A case-control analysis was performed, with patients matched for duration of amiodarone therapy. Of the 92 patients (age, 34.9+/-10.2 years; range, 18 to 60 years), 36% developed thyroid dysfunction: 19 became hyperthyroid and 14 hypothyroid. Female sex and complex cyanotic heart disease were significant risk factors for developing thyroid dysfunction (odds ratios, 3.0 and 7.00; P=0.04 and 0.01, respectively). Previous Fontan-type surgery also appeared to be a risk factor for developing thyrotoxicosis (odds ratio, 4.0; P=0.17), and amiodarone >200 mg/d a risk factor for thyroid dysfunction (odds ratio, 4.0; P=0.60).

CONCLUSIONS:

Amiodarone-associated thyroid dysfunction is common in adults with congenital heart disease. Women and those with complex cyanotic lesions are at particular risk, as patients may be who have had Fontan-type surgery or are taking >200 mg/d of amiodarone. Amiodarone should be used only when other antiarrhythmics are ineffective or contraindicated. Vigilance is required to detect and treat thyroid dysfunction.

• Authors: S A Thorne, I Barnes, P Cullinan, J Somerville
• Journal: Circulation (Circulation) Vol. 100 Issue 2 Pg. 149-54 (Jul 13 1999) ISSN: 1524-4539 [Electronic] United States
• PMID: 10402444 (Publication Type: Journal Article)

Chemical References

• Anti-Arrhythmia Agents
• Amiodarone

Topics

• Adolescent
• Adult
• Amiodarone (adverse effects, therapeutic use)
• Anti-Arrhythmia Agents (adverse effects, therapeutic use)
• Case-Control Studies
• Female
• Heart Defects, Congenital (drug therapy)
• Humans
• Male
• Middle Aged
• Retrospective Studies
• Risk Factors
• Thyroid Diseases (chemically induced)