RESEARCH ARTICLE
Incidence and Pattern of Thyroid Dysfunction in Patients on Chronic Amiodarone Therapy: Experience at a Tertiary Care Centre in Oman
H. Farhan1, A. Albulushi*, 1, A. Taqi2, A. Al-Hashim1, K. Al-Saidi1, K. Al-Rasadi3, A. Al-Mazroui1, I. Al-Zakwani4, 5
Article Information
Identifiers and Pagination:
Year: 2013Volume: 7
First Page: 122
Last Page: 126
Publisher ID: TOCMJ-7-122
DOI: 10.2174/1874192401307010122
Article History:
Received Date: 1/11/2013Acceptance Date: 4/11/2013
Electronic publication date: 29 /11/2013
Collection year: 2013

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
Objective:
To determine the incidence and pattern of thyroid dysfunction (TD) in patients on chronic amiodarone therapy.
Methods:
A retrospective study which evaluated 59 patients who had received amiodarone therapy regularly for at least 12 months from a period of 3 years from October 2007 to October 2010. The patients were followed-up at the cardiac clinic at Sultan Qaboos University Hospital, Muscat, Oman.
Results:
The mean age of the cohort was 63 ± 13 years ranging from 27 to 98 years. Fifty-one percent (n = 30) of the patients were female. There were 11 (19%) cases of thyroid dysfunction (TD). Seven (12%) patients were hypothyroid, 3 (5%) had hyperthyroidism and 1 (2%) patient had sub-clinical hypothyroidism; no cases of sub-clinical hyperthyroidism were noted. Female gender and presence of anti-thyroid peroxidase antibodies were significantly associated with amiodarone-induced hypothyroidism (p = 0.001) while age, amiodarone dose and duration of therapy were not correlated with the development of TD (all p-values > 0.05).
Conclusion:
Amiodarone-induced thyroid dysfunction is prevalent. Hypothyroidism was more frequent and seen more in female patients and those who had positive anti-thyroid peroxidase antibodies. Initial screening and periodic monitoring of thyroid function is mandatory for all patients on amiodarone therapy.