Amiodarone-induced thyrotoxicosis (AIT) resulting from destructive thyroiditis (type 2) is commonly treated with glucocorticoids, but time needed to restore euthyroidism may be unacceptable for patients with underlying cardiac disorders. OBJECTIVE: The objective of this prospective study was to identify factors affecting the response to glucocorticoids in a large cohort of patients with type 2 AIT followed prospectively. SETTING: This study was conducted at university centers. PATIENTS: Sixty-six untreated patients with type 2 AIT were enrolled in the study. INTERVENTION: All patients were treated with prednisone (initial dose, 0.5 mg/kg.d) as long as needed to restore euthyroidism, defined as cure of AIT. MAIN OUTCOME MEASURE: The main outcome measure was cure time. RESULTS: The median cure time was 30 d (95% confidence interval, 23-37 d). Serum free T4 concentration (picograms per milliliter) and thyroid volume (milliliters per square meter) (and, to a lesser extent, serum free T3 concentration) at diagnosis were the main determinants of response to glucocorticoids, with a cure hazard ratio of 0.97 (95% confidence interval, 0.95-0.99; P = 0.005) and 0.84 (95% confidence interval, 0.77-0.91; P = 0.000) for unit of increment, respectively. AIT was cured in all patients with a complete follow-up; euthyroidism was reached in 30 d or less in 60% of patients but in more than 90 d in 16%. A prompt control of thyrotoxicosis (<or=30 d of treatment) was more frequent (77%) in patients with serum basal free T4 concentration no greater than 50 pg/ml and thyroid volume (normalized for body surface area) no greater than 12 ml/m2. The cure probability and the mean cure time in an individual patient can be obtained using a formula generated by multiple regression models. CONCLUSIONS: Baseline serum thyroid hormone concentrations and thyroid volume help identify patients with type 2 AIT at risk of a delayed response to glucocorticoids.

Glucocorticoid response in amiodarone-induced thyrotoxicosis resulting from destructive thyroiditis is predicted by thyroid volume and serum free thyroid hormone concentrations

BOGAZZI, FAUSTO;MARTINO, ENIO
2007

Abstract

Amiodarone-induced thyrotoxicosis (AIT) resulting from destructive thyroiditis (type 2) is commonly treated with glucocorticoids, but time needed to restore euthyroidism may be unacceptable for patients with underlying cardiac disorders. OBJECTIVE: The objective of this prospective study was to identify factors affecting the response to glucocorticoids in a large cohort of patients with type 2 AIT followed prospectively. SETTING: This study was conducted at university centers. PATIENTS: Sixty-six untreated patients with type 2 AIT were enrolled in the study. INTERVENTION: All patients were treated with prednisone (initial dose, 0.5 mg/kg.d) as long as needed to restore euthyroidism, defined as cure of AIT. MAIN OUTCOME MEASURE: The main outcome measure was cure time. RESULTS: The median cure time was 30 d (95% confidence interval, 23-37 d). Serum free T4 concentration (picograms per milliliter) and thyroid volume (milliliters per square meter) (and, to a lesser extent, serum free T3 concentration) at diagnosis were the main determinants of response to glucocorticoids, with a cure hazard ratio of 0.97 (95% confidence interval, 0.95-0.99; P = 0.005) and 0.84 (95% confidence interval, 0.77-0.91; P = 0.000) for unit of increment, respectively. AIT was cured in all patients with a complete follow-up; euthyroidism was reached in 30 d or less in 60% of patients but in more than 90 d in 16%. A prompt control of thyrotoxicosis (
Bogazzi, Fausto; L., Bartalena; L., Tomisti; G., Rossi; M. L., Tanda; E., Dell'Unto; F., AGHINI LOMBARDI; Martino, Enio
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11568/194554
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact