Use of iodinated contrast media in imaging procedures appears to affect thyroid function

January 23, 2012

Exposure to iodinated contrast media during imaging procedures is associated with changes in thyroid function, and increased risk of developing hyperthyroidism, according to a report in the January 23 issue of Archives of Internal Medicine.

"Iodinated contrast media (ICM) are commonly administered pharmaceutical agents," the authors write as background information. ICM are frequently used in scans and imaging procedures such as and computed tomography (CT scans). "Although certain complications of ICM (e.g., contrast-induced nephropathy) have been extensively studied, there has been little examination of the effect of ICM on ."

Connie M. Rhee, M.D., and colleagues from Brigham and Women's Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, examined data from patients treated between January 1990 and June 2010 who did not have preexisting or . Patients were matched with euthyroid (normal thyroid function) controls, and to iodinated contrast media was assessed using claims data.

A total of 178 patients with incident hyperthyroidism and 213 patients with incident hypothyroidism were matched to 655 and 779 euthyroid persons, respectively. The authors found that iodinated contrast media exposure was associated with incident hyperthyroidism, but no statistically significant association was found with incident hypothyroidism.

Secondary analysis indicated an association between iodinated contrast media exposure and incident overt (clinical; diagnosed based on characteristic clinical features) hypothyrodism and incident overt (clinical) hyperthyroidism.

"In summary, these data support association between ICM exposure and incident hyperthyroidism, incident overt hyperthyroidism and incident overt hypothyroidism," the authors conclude. "Given the pervasive use of ICM in contemporary practice and the known sequelae of thyroid functional derangements, further studies are needed to confirm and evaluate generalizability of these findings, to establish causality and to explore mechanisms."

In an accompanying invited commentary, Elizabeth N. Pearce, M.D., M.Sc., of Boston University School of Medicine writes that Rhee et al "describe significant associations between contrast exposure and the development of hyperthyroidism. While no overall association exists between contrast exposure and all forms of hypothyroidism, an association was noted when cases were restricted to those with overt hypothyroidism."

"These data represent an important contribution to our knowledge about a clinically relevant and understudied area," Dr. Pearce writes. "Rhee et al have demonstrated that a relatively large proportion of individuals who developed iodine-induced thyroid dysfunction were not known to have underlying risk factors. Therefore, patients who may be particularly unable to tolerate thyroid dysfunction, such as those with underlying unstable cardiovascular disease, are also good candidates for monitoring of function after iodine exposure."

Explore further: Elderly may be more likely to die if they have subclinical hyperthyroidism

More information: Arch Intern Med. 2012;172[2]:153-159.
Arch Intern Med. 2012;172[2]:159-161.

Related Stories

Elderly may be more likely to die if they have subclinical hyperthyroidism

June 6, 2011
A common hormone abnormality in older adults -- a mild form of overactive thyroid called subclinical hyperthyroidism -- is linked to a much higher risk of dying, a new study finds. The results will be presented Sunday at ...

Harmful effects of hypothyroidism on maternal and fetal health drive new guidelines for managing thyroid disease in preg

July 25, 2011
Emerging data clarifying the risks of insufficient thyroid activity during pregnancy on the health of the mother and fetus, and on the future intellectual development of the child, have led to new clinical guidelines for ...

No difference in brand name and generic drugs regarding thyroid dysfunction

July 11, 2011
There is no difference between brand-name and generic drug formulations of amiodarone -- taken to control arrhythmia – in the incidence of thyroid dysfunction, according to a study in CMAJ (Canadian Medical Association ...

Recommended for you

New therapeutic approach for difficult-to-treat subtype of ovarian cancer identified

July 24, 2017
A potential new therapeutic strategy for a difficult-to-treat form of ovarian cancer has been discovered by Wistar scientists. The findings were published online in Nature Cell Biology.

Anti-cancer chemotherapeutic agent inhibits glioblastoma growth and radiation resistance

July 24, 2017
Glioblastoma is a primary brain tumor with dismal survival rates, even after treatment with surgery, chemotherapy and radiation. A small subpopulation of tumor cells—glioma stem cells—is responsible for glioblastoma's ...

Immune cells the missing ingredient in new bladder cancer treatment

July 24, 2017
New research offers a possible explanation for why a new type of cancer treatment hasn't been working as expected against bladder cancer.

No dye: Cancer patients' gray hair darkened on immune drugs

July 21, 2017
Cancer patients' gray hair unexpectedly turned youthfully dark while taking novel drugs, and it has doctors scratching their heads.

Shooting the achilles heel of nervous system cancers

July 20, 2017
Virtually all cancer treatments used today also damage normal cells, causing the toxic side effects associated with cancer treatment. A cooperative research team led by researchers at Dartmouth's Norris Cotton Cancer Center ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.