Clinical trial NCT00471458: Follow-up Study of the RAI-Treated Hyperthyroid Patients
Official title: Follow-up Study of Hyperthyroid Patients Treated With RAI in 1965-2002: Morbidity in Long-Term Follow-up
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hyperthyroidism
Cardiovascular Diseases
Atrial Fibrillation
Keywords: Radioiodine
Hyperthyroidism
Morbidity
Cardiovascular diseases
Lead sponsor: Tampere University
Sponsor class: OTHER
First posted: 2007-05-10
Enrollment: 5222
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: DEFINED_POPULATION
Time perspective: RETROSPECTIVE

Brief summary: Previous studies of hyperthyroid patients suggest that they remain at increased risk of cardiovascular morbidity after restoring euthyroidism.

The study objective is to compare the rate and causes of hospitalization of hyperthyroid patients treated with radioactive iodine (RAI) with those of an age- and gender-matched reference population in a long-term follow-up study.

Detailed description: A population-based cohort study was conducted among 2611 hyperthyroid patients treated with RAI between 1969 and 2002 in Tampere University Hospital, and among 2611 reference subjects. A reference group was randomly selected, with an age- and gender-matched control subject identified for each patient from the Population Register Centre. The control subject had to be alive at the time when the patient received the first RAI treatment.

The causes of hospitalization as well as the diagnosis and date of hospital admission were obtained from the nationwide Hospital Discharge Register (HILMO) maintained by the Research and Development Centre for Welfare and Health (STAKES) using a computerized record linkage, with the personal identification number as the key. The HILMO database covers all dates and causes of hospitalization (hospital admission requiring an overnight stay) of the Finnish citizens since January 1969. New events were analyzed as the main outcome, including only the first hospitalization due to a given indication. The special focus was on the cardiovascular morbidity.

Eligibility criteria: Inclusion Criteria:

* Patients: Radioiodine treatment for hyperthyroidism given in the Tampere University Hospital between January 1969 and June 2002
* Controls: age- and gender-matched control subject identified for each patient from the Population Register Centre. The control subject had to be alive at the time when the patient received the first RAI treatment

Primary outcomes:
Secondary outcomes:
Other outcomes:
Locations:
city: Tampere
country: Finland
facility: Tampere University Hospital, Department of Internal Medicine
Study officials:
affiliation: Tampere University Hospital, Department of Internal Medicine, FIN-33521 Tampere, Finland
name: Saara Metso, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Medical School, University of Tampere, Tampere, FINLAND
name: Pia Jaatinen, MD, PhD
role: STUDY_DIRECTOR
affiliation: Tampere University Hopsital, Department of Internal Medicine, FIN-33521 TAMPERE, FINLAND
name: Jorma Salmi, MD, PhD
role: STUDY_DIRECTOR
References:
citation: Metso S, Jaatinen P, Huhtala H, Luukkaala T, Oksala H, Salmi J. Long-term follow-up study of radioiodine treatment of hyperthyroidism. Clin Endocrinol (Oxf). 2004 Nov;61(5):641-8. doi: 10.1111/j.1365-2265.2004.02152.x.
citation: Metso S, Auvinen A, Huhtala H, Salmi J, Oksala H, Jaatinen P. Increased cancer incidence after radioiodine treatment for hyperthyroidism. Cancer. 2007 May 15;109(10):1972-9. doi: 10.1002/cncr.22635.
citation: Metso S, Jaatinen P, Huhtala H, Auvinen A, Oksala H, Salmi J. Increased cardiovascular and cancer mortality after radioiodine treatment for hyperthyroidism. J Clin Endocrinol Metab. 2007 Jun;92(6):2190-6. doi: 10.1210/jc.2006-2321. Epub 2007 Mar 20.