Iodinated Contrast Media Induced Hyperthyroidism

NCT ID: NCT04304794

Last Updated: 2020-03-11

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 36 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2015-01-02
• Study Completion Date: 2020-02-20

Brief Summary

The proper synthesis of thyroid hormones is dependent on adequate iodine supply. The mean daily iodine intake recommended by World Health Organization is 150 mg. Iodinated contrast medium (ICM) typically contains 13 500 mg of free iodine and 15-60 g of bound iodine, an amount well above acceptable upper level. In a situation of excess iodine, thyroid discontinues the release of hormones (Wolff-Chaikoff effect), which is usually transient, although can persist causing hypothyroidism. Iodine-induced hyperthyroidism (IIH), known as the Jod-Basedow phenomenon is infrequent, but elderly patients and individuals with autonomously functioning nodular goiters are at higher risk of developing this dysfunction. According to recent studies the risk of ICM-induced hyperthyroidism appears to be low. The prevalence has not been well assessed and varies from 1 % to 10 %. Currently, there are no specific guidelines concerning the prophylactic therapy of IIH. American Thyroid Association (ATA) does not recommend routine administration of antithyroid drugs before iodinated contrast medium for all patients, however, advises to consider prophylaxis in patients at high risk of developing IIH or with cardiovascular comorbidities. ATA recommends avoidance of additional iodine and administration of b-blockers alone or with antithyroid drugs as a treatment of IIH, depending on the severity of hyperthyroidism.

This study was performed to evaluate the influence of ICM on thyroid status and advantages of prophylactic therapy during ICM exposure in patients with euthyroid goiter and cardiovascular comorbidities. The association between the incidence of IIH and thyroid volume was also assessed.

Detailed Description

Patients were divided into two subsets on the basis of received prophylactic therapy. Group with prophylaxis (13 patients) received thiamazole alone (7 patients) or with sodium perchlorate (6 patients). The prophylaxis was administered one day prior to iodinated contrast medium (ICM) and for at least 14 days after ICM for thiamazole (20-40 mg/daily) and 10 days after ICM for sodium perchlorate (900 mg/daily). Group without prophylaxis (23 patients) received no prophylactic treatment. Laboratory tests were performed before and after ICM injection in all patients from both evaluated groups. Each individual had TSH and creatinine level measured at baseline. The investigators analyzed clinical data such as age, sex, mean volume of contrast media, goiter size and patients' comorbidities. Levels of TSH, FT3 and FT4 were evaluated retrospectively at different points in time after ICM. Ultrasonography was performed in each patient to assess thyroid morphology. The investigators performed a comparison between both groups in regard to duration of overt hyperthyroidism and thiamazole treatment. Thyroid volume was compared between patients who developed hyperthyroidism after ICM injection and remained euthyroid after ICM injection. Patients diagnosed with overt hyperthyroidism were treated with thiamazole.

Conditions

Hyperthyroidism/Thyrotoxicosis; Hyperthyroidism; Goiter; Iodine Induced Thyrotoxicosis; Contrast Media Adverse Reaction; Thyrotoxicosis of Other Specified Origin

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: RETROSPECTIVE

Study Groups

Group with prophylaxis

Group of 13 patients with euthyroid goiter who received prophylactic treatment before and after iodinated contrast medium (ICM) injection. 6 patients received thiamazole with sodium perchlorate, one day prior to ICM and for at least 14 days after for thiamazole (20-40 mg/daily) and 10 days after for sodium perchlorate (900 mg/daily). 7 patients received only thiamazole as prophylactic treatment due to lack of sodium perchlorate at the time.

Administration of iodinated contrast media

Intervention Type: PROCEDURE

Each patient was exposed on iodinated contrast medium administered during computed tomography, coronary angiography or transcatheter aortic valve implantation.

Prophylactic administration of antithyroid drugs before iodinated contrast media exposure

Intervention Type: DRUG

13 patients received thiamazole with (6 patients) or without (7 patients) sodium perchlorate, one day prior to iodinated contrast medium (ICM) and for at least 14 days after for thiamazole (20-40 mg/daily) and 10 days after for sodium perchlorate (900 mg/daily).

Group without prophylaxis

Group of 23 patients with euthyroid goiter who received no prophylactic treatment before iodinated contrast medium injection.

Administration of iodinated contrast media

Intervention Type: PROCEDURE

Each patient was exposed on iodinated contrast medium administered during computed tomography, coronary angiography or transcatheter aortic valve implantation.

Interventions

Administration of iodinated contrast media

Each patient was exposed on iodinated contrast medium administered during computed tomography, coronary angiography or transcatheter aortic valve implantation.

Intervention Type: PROCEDURE

Prophylactic administration of antithyroid drugs before iodinated contrast media exposure

13 patients received thiamazole with (6 patients) or without (7 patients) sodium perchlorate, one day prior to iodinated contrast medium (ICM) and for at least 14 days after for thiamazole (20-40 mg/daily) and 10 days after for sodium perchlorate (900 mg/daily).

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• euthyroidism at baseline (defined as TSH level within the reference range)
• diffuse or multinodular goiter
• iodinated contrast media (ICM) exposure
• time of observation after ICM exposure longer than 4 weeks

Exclusion Criteria

• Graves' disease
• administration of thyroid hormones, glucocorticoids, iodine-containing medications or iodine contrast agent within the past 6 months

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

National Institute of Cardiology, Warsaw, Poland

OTHER

Sponsor Role: collaborator

Medical University of Warsaw

OTHER

Sponsor Role: lead

Responsible Party

Piotr Miskiewicz

Assistant professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Piotr Miśkiewicz, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Department of Endocrinology Medical University of Warsaw

Other Identifiers

ICMThyro

Identifier Type: -

Identifier Source: org_study_id