Determinants and outcome of amiodarone-associated thyroid dysfunction.
Clin Endocrinol (Oxf)
; 75(3): 388-94, 2011 Sep.
Article
de En
| MEDLINE
| ID: mdl-21535072
ABSTRACT
OBJECTIVE:
Amiodarone is frequently associated with thyroid dysfunction. Identifying predictors for amiodarone-associated thyroid dysfunction and assessing treatment outcome may aid clinicians in daily practice.METHODS:
We included 303 consecutive patients with amiodarone therapy for cardiac arrhythmias (260 with atrial fibrillation and 43 with ventricular arrhythmias). Thyroid function tests were performed every 6 months.RESULTS:
Mean age was 63 ± 12 years and 66% was male. After median follow-up of 3·3 (0·1-24) years, 23 (8%) patients developed amiodarone-associated thyrotoxicosis (incidence rate 1·9 per 100 person years) and 18 (6%) hypothyroidism (incidence rate 1·1 per 100 person years). The only predictor for amiodarone-associated thyrotoxicosis was age <62 years [HR = 2·4 (95% CI 1·0-5·7), P = 0·05]. Predictors for amiodarone-associated hypothyroidism were thyroid stimulating hormone >1·4 mU/l at baseline [HR = 5·1 (95% CI 1·1-22·4), P = 0·03], left ventricular ejection fraction <45% [HR = 3·8 (95% CI 1·1-13·3), P = 0·04] and diabetes mellitus at baseline [HR = 3·3 (95% CI 1·1-10·3), P = 0·04]. Gender was not a predictor for amiodarone-associated thyroid dysfunction. Five out of 12 (42%) patients with thyrotoxicosis exhibited spontaneous normalization of thyroid function on continuation of amiodarone therapy. Mean time to normalization in the total group was 6·2 ± 3·3 months, with no difference between continuing or discontinuing amiodarone (6·6 ± 3·8 vs 5·8 ± 2·8 months, P = 0·5).CONCLUSIONS:
During median follow-up of 3·3 years, the incidence of amiodarone-associated thyrotoxicosis was higher compared to hypothyroidism. Only general predictors for amiodarone-associated thyroid dysfunction were observed. Discontinuation of amiodarone did not influence treatment outcome.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Troubles du rythme cardiaque
/
Thyréotoxicose
/
Amiodarone
/
Hypothyroïdie
Type d'étude:
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limites:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Langue:
En
Journal:
Clin Endocrinol (Oxf)
Année:
2011
Type de document:
Article
Pays d'affiliation:
Pays-Bas