Amiodarone-induced thyrotoxicosis late after amiodarone withdrawal.

Abstract

BACKGROUND:

Amiodarone-induced thyrotoxicosis (AIT) may develop long after amiodarone withdrawal. This study sought to determine the incidence and clinical characteristics of AIT after amiodarone withdrawal.

METHODS AND RESULTS:

The incidence and clinical characteristics of AIT were examined retrospectively in 71 patients (51 males, mean age 65±13 years) whose amiodarone therapy had been discontinued after at least 1 month of administration. Five (7%) patients developed AIT late after amiodarone withdrawal (11±3 months): 2 patients exhibited exacerbation of heart failure by atrial fibrillation, 2 developed dyspnea on exertion, and 1 patient was asymptomatic. The patients who developed AIT had a high incidence of amiodarone-induced hypothyroidism during amiodarone therapy (100 vs. 24%, P=0.002), had received amiodarone therapy for longer (76±86 months vs. 16±22 months, P<0.001), with a larger cumulative dose (271.1±268.5 g vs. 63.4±86.5 g, P<0.001) compared with those who did not. In all 5 patients, AIT resolved spontaneously within 5 months without the use of steroids.

CONCLUSIONS:

Occurrence of amiodarone-induced hypothyroidism during amiodarone therapy and long duration of therapy may be cautionary markers of late AIT.

• Authors: Atsuhiko Yagishita, Hitoshi Hachiya, Mihoko Kawabata, Tomofumi Nakamura, Koji Sugiyama, Yasuaki Tanaka, Tetsuo Sasano, Mitsuaki Isobe, Kenzo Hirao
• Journal: Circulation journal : official journal of the Japanese Circulation Society (Circ J) Vol. 77 Issue 12 Pg. 2898-903 ( 2013) ISSN: 1347-4820 [Electronic] Japan
• PMID: 24042320 (Publication Type: Clinical Trial, Journal Article, Multicenter Study)

Chemical References

• Anti-Arrhythmia Agents
• Amiodarone

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Amiodarone (administration & dosage, adverse effects)
• Anti-Arrhythmia Agents (administration & dosage, adverse effects)
• Atrial Fibrillation (chemically induced, epidemiology)
• Dyspnea (chemically induced, epidemiology)
• Female
• Humans
• Male
• Middle Aged
• Retrospective Studies
• Thyrotoxicosis (chemically induced, epidemiology)
• Time Factors