An observational study in All-Cause Mortality, Circulatory and Other Disease Mortality and Thyroid and Other Cancer Mortality, sponsored by National Cancer Institute (NCI). Completed at 1 site in United States. Open to participants aged 18 Years to 105 Years. Per ClinicalTrials.gov, last updated 2020-10-29.
Sponsored by National Cancer Institute (NCI) · Observational
Background:
Hyperthyroidism is a common disease. It is very common for women. It is usually treated with Radioiodine (I-131). Some people think that this might cause cancer, even many years later. Past studies of people with hyperthyroidism have not been clear about cancer risks after I-131. Researchers want to look at a group of people with the disease who got I-131 many years ago. They want to look at how their health was months and years later.
Objective:
To learn more about disease risks in relation to radiation from I-131 treatment for hyperthyroidism.
Eligibility:
People who were part of the previous study. These are people who were diagnosed with hyperthyroidism at U.S. and U.K. hospitals from 1946 to 1964. About 95% of the participants have already died.
Design:
Researchers will examine data already collected by the past study. This includes data on participants later cancers and other health outcomes after they had I-131 treatment.
Researchers will compare that data to a National Death Index search.
This was already done for data up through 2003. This study will cover 2004 2014.
Researchers will not be in touch with study participants or their next of kin....
Hyperthyroidism (thyrotoxicosis) is a relatively common disease, especially among women, and radioiodine (I-131) administration is the treatment of choice for most adult patients. There is concern about possible carcinogenic effects of I-131 therapy, but previous studies of hyperthyroid patients have not presented clear results regarding cancer risks following I-131 treatment. There also is public concern regarding late health consequences of I-131 exposure as this radioiodine is one of the primary release products from nuclear power generation and a principal component in fallout from nuclear power plant accidents. The Thyrotoxicosis Therapy Follow-up Study (TTFUS) cohort, assembled in 1961, comprises 35,000 subjects treated for hyperthyroidism at over 20 medical centers in the US and one in Great Britain between 1946 and 1964. This is among the largest group of hyperthyroid patients that has been followed up for subsequent cancer and other health outcomes. The proposed mortality follow-up study will enable us to assess nearly lifetime risk of cancer and other diseases in this unique cohort. Mortality follow-up data will extend the observation through 2015, adding 15 more years, via linkage with the National Death Index search. Recently estimated I-131 radiation doses to various body organs will allow refined dose response analysis, providing most definitive assessment of the nature and magnitude of the risk of cancer and other disease associated with I-131 exposure as well as end-results of I-131 and other treatment for hyperthyroidism.
111 studies on the registry are indexed under Hyperthyroidism; 28 are open to participants now.
This study's enrollment of 35,593 is above the median of 100 across 55 observational studies indexed under Hyperthyroidism.
Browse Hyperthyroidism studies →National Cancer Institute (NCI) is the lead sponsor of 3,506 studies on the registry; 334 are open to participants now.
Of its 402 completed or terminated interventional studies of FDA-regulated products, 365 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
The cohort includes all hypothyroid patients treated with I-131, thyroid surgery, anti-thyroid drugs, or any combinations of these treatments between 1946 and 1964 at 25 U.S. and 1 UK institution. The cohort is largely female (79%), with a mean age at study entry (in 1961) of 46 years old. Hyperthyroidism patients in the cohort are classified as those with Graves disease (91%), toxic nodular goiter (8%), and unknown (1%).
Individuals treated for hyperthyroidism registered within the Thyrotoxicosis Therapy Follow-up Study (TTFUS) cohort that was assembled in 1961.
EXCLUSION:
Any individual that was NOT treated for hyperthyroidism registered within the Thyrotoxicosis Therapy Follow-up Study (TTFUS) cohort that was assembled in 1961.
Hyperthyroid patients enrolled and treated between 1946 and 1964 in 25 U.S. and 1 UK site
Cancer mortality rates
Mortality rates due to cancer in the cohort population.
Time frame: 1946 to 2014
Non-cancer mortality
Mortality rates due to non-cancer in the cohort population
Time frame: 1946 to 2014
This study is completed, as verified in Oct 2020. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
National Cancer Institute (NCI)