Amiodarone-induced thyroid dysfunction
| dc.contributor.author | Ross, Ian Louis | |
| dc.contributor.author | Marshall, David | |
| dc.contributor.author | Okreglicki, Andrzej | |
| dc.contributor.author | Isaacs, Sedick | |
| dc.contributor.author | Levitt, Naomi Sharlene | |
| dc.date.accessioned | 2018-03-13T08:23:00Z | |
| dc.date.available | 2018-03-13T08:23:00Z | |
| dc.date.issued | 2005 | |
| dc.date.updated | 2016-01-16T06:38:06Z | |
| dc.description.abstract | Background. Little is known about the frequency of thyroid dysfunction (TD) associated with amiodarone therapy in southern Africa. Objectives. To determine the incidence of TD in a cohort of patients initiated on amiodarone therapy at a cardiac clinic in Cape Town, South Africa, believed to be an iodine-replete area. Patients. Pharmacy records were used to obtain the names of patients who received amiodarone between November 1999 and December 2002. Results. The sample size was 194, but data analysis was limited to the 163 patients for whom there were complete data. The mean age ± standard deviation (SD) was 59.0 ± 15.0 years (range 22 - 89 years). There were 67 female and 96 male patients. The indications for amiodarone therapy were supraventricular tachycardias (N = 102, 62.6%), ventricular tachycardia (N = 55, 33.7%), and prophylaxis against tachycardias (N = 3, 1.8%). The indication was uncertain in 3 patients (1.8%). The median duration of amiodarone treatment was 679.0 days (quartile deviation (QD) 1 172 days, range 3 - 6 425 days) in the whole cohort. The median duration of amiodarone therapy until new TD was 943 days (QD 1 185 days), significantly longer than in patients who remained euthyroid (547 days, QD 1 135 days) (P = 0.05). There were 45 new TD cases (27.6%): 11 patients (6.7%) were thyrotoxic, 1(0.6%) transient thyrotoxicosis, 1 (0.6%) subclinical hyperthyroidism, 13 (8.0%) had subclinical hypothyroidism, 12 (7.4%) hypothyroidism and 7 (4.3%) had minor changes in thyroid function. Conclusions. We found a high incidence of new-onset TD, similar to the highest rates reported internationally. Local factors responsible for this need to be investigated. | |
| dc.identifier.apacitation | Ross, I. L., Marshall, D., Okreglicki, A., Isaacs, S., & Levitt, N. S. (2005). Amiodarone-induced thyroid dysfunction. <i>South African Medical Journal</i>, http://hdl.handle.net/11427/27640 | en_ZA |
| dc.identifier.chicagocitation | Ross, Ian Louis, David Marshall, Andrzej Okreglicki, Sedick Isaacs, and Naomi Sharlene Levitt "Amiodarone-induced thyroid dysfunction." <i>South African Medical Journal</i> (2005) http://hdl.handle.net/11427/27640 | en_ZA |
| dc.identifier.citation | Ross, I. L., Marshall, D., Okreglicki, A., Isaacs, S., & Levitt, N. S. (2005). Amiodarone-induced thyroid dysfunction: original article. South African Medical Journal, 95(3), p-180. | |
| dc.identifier.ris | TY - Journal Article AU - Ross, Ian Louis AU - Marshall, David AU - Okreglicki, Andrzej AU - Isaacs, Sedick AU - Levitt, Naomi Sharlene AB - Background. Little is known about the frequency of thyroid dysfunction (TD) associated with amiodarone therapy in southern Africa. Objectives. To determine the incidence of TD in a cohort of patients initiated on amiodarone therapy at a cardiac clinic in Cape Town, South Africa, believed to be an iodine-replete area. Patients. Pharmacy records were used to obtain the names of patients who received amiodarone between November 1999 and December 2002. Results. The sample size was 194, but data analysis was limited to the 163 patients for whom there were complete data. The mean age ± standard deviation (SD) was 59.0 ± 15.0 years (range 22 - 89 years). There were 67 female and 96 male patients. The indications for amiodarone therapy were supraventricular tachycardias (N = 102, 62.6%), ventricular tachycardia (N = 55, 33.7%), and prophylaxis against tachycardias (N = 3, 1.8%). The indication was uncertain in 3 patients (1.8%). The median duration of amiodarone treatment was 679.0 days (quartile deviation (QD) 1 172 days, range 3 - 6 425 days) in the whole cohort. The median duration of amiodarone therapy until new TD was 943 days (QD 1 185 days), significantly longer than in patients who remained euthyroid (547 days, QD 1 135 days) (P = 0.05). There were 45 new TD cases (27.6%): 11 patients (6.7%) were thyrotoxic, 1(0.6%) transient thyrotoxicosis, 1 (0.6%) subclinical hyperthyroidism, 13 (8.0%) had subclinical hypothyroidism, 12 (7.4%) hypothyroidism and 7 (4.3%) had minor changes in thyroid function. Conclusions. We found a high incidence of new-onset TD, similar to the highest rates reported internationally. Local factors responsible for this need to be investigated. DA - 2005 DB - OpenUCT DP - University of Cape Town J1 - South African Medical Journal LK - https://open.uct.ac.za PB - University of Cape Town PY - 2005 T1 - Amiodarone-induced thyroid dysfunction TI - Amiodarone-induced thyroid dysfunction UR - http://hdl.handle.net/11427/27640 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/27640 | |
| dc.identifier.vancouvercitation | Ross IL, Marshall D, Okreglicki A, Isaacs S, Levitt NS. Amiodarone-induced thyroid dysfunction. South African Medical Journal. 2005; http://hdl.handle.net/11427/27640. | en_ZA |
| dc.language.iso | eng | |
| dc.publisher.department | Division of Endocrinology and Diabetology | en_ZA |
| dc.publisher.faculty | Faculty of Health Sciences | en_ZA |
| dc.publisher.institution | University of Cape Town | |
| dc.source | South African Medical Journal | |
| dc.source.uri | http://www.samj.org.za | |
| dc.subject.other | Thyroid dysfunction | |
| dc.subject.other | Amiodarone therapy | |
| dc.subject.other | Southern Africa | |
| dc.title | Amiodarone-induced thyroid dysfunction | |
| dc.type | Journal Article | |
| uct.type.filetype | Text |