None listed
Conditions
Interventions
Randomized clinical trial comparing active treatment with 131I with no treatment in
subjects with endogenous subclinical hyperthyroidism in a multicenter study.
Sponsors
None listed
Eligibility
Inclusion criteria
Inclusion criteria: 1. Subclinical hyperthyroidism [TSH <= 0.1 mU/L, fT4 and T3 within the normal range of the own laboratory (determined 2 times in own laboratory with an interval of at least 2 months]; 2. Endogenous cause of subclinical hyperthyroidism limited to autonomous adenoma or multinodular goiter (diagnosis made by the attending physician, based on palpation and the result of a thyroid scintigram); 3. Informed consent.
Exclusion criteria
Exclusion criteria: 1. Medication with anti-thyroid drugs in the last 3 months (also not allowed during follow-up), thyroid hormone in the last 3 months (allowed during follow-up, but TSH levels should be kept between 0.1 mU/L and the upper limit of normal in the own laboratory) and oral glucocorticoids in the last 3 months (allowed during follow-up when absolutely necessary, but patients in whom glucocorticoids are started cannot be evaluated with respect to changes in BMD); 2. Radioiodine therapy in the past; 3. Iodine-induced subclinical hyperthyroidism; 4. Pituitary or hypothalamic insufficiency; 5. Pregnancy; 6. Age 80 years; 7. Severe non-thyroidal illness; 8. Drug abuse; 9. Unstable angina pectoris, (history of) atrial fibrillation, (history of) congestive heart failure; 10. (History of) osteoporotic fracture(s); 11. Patients younger than 70 years of age with a bone mineral density T-score <–2.5 SD, or older than 70 years of age with a bone mineral density Z-score <1.0 SD; 12. These patients can be randomized but in case it is decided to treat them with antiosteoporotic drugs they cannot be evaluated with respect to changes in BMD; 13. Use of betablockers in the last three months. These patients can be randomised but cannot be evaluated with respect to general and cardiac symptoms. The same applies to patients in whom betablokkers are started during follow up; 14. Other symptoms or signs of hyperthyroidism or obstruction of vital structures which in the opinion of the attending physician urge to active treatment.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Progression to overt hyperthyroidism: TSH, fT4, T3 every year; 2. Changes in (thyrotoxic) symptoms (null-hypothesis: radioiodine does not cause improvement): 2.1 Quality of life – short form 36 Health Survey: on T=0, T=2 and T=5 years; 2.2 Modified hyperthyroid symptom scale: on T=0, T=2 and T=5 years; 2.3 In the treatment group on T= 1 year: duration of admission to hospital for administration of I131 (if necessary) and signs or symptoms of iodine induced thyroiditis or Graves like disease following iodine treatment making medical treatment necessary; 3. Cardiac changes (null-hypothesis: radioiodine does not prevent development of atrial fibrillation): 3.1 12-lead ECG: on T=0, T=2 and T=5 years; 3.2 Holter monitoring (24 hour): mean 24-hour heart rate, number of PAC and VES: on T=0, T=2 and T=5 years; 4. Changes in bone mineral density (null-hypothesis: radioiodine does not prevent deterioration of BMD): DEXA (Hologic or Lunar) L1-L4 and (right) femoral neck): on T=0, T=2 and T=5 years. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Progression to overt hyperthyroidism: TSH, fT4, T3 every year. 2. Changes in (thyrotoxic) symptoms (null-hypothesis: radioiodine does not cause improvement): a. Quality of life – short form 36 Health Survey: on T=0, T=2 and T=5 years; b. Modified hyperthyroid symptom scale: on T=0, T=2 and T=5 years; c. In the treatment group on T= 1 year: duration of admission to hospital for administration of I131 (if necessary) and signs or symptoms of iodine induced thyroiditis or Graves like disease following iodine treatment making medical treatment necessary; 3. Cardiac changes (null-hypothesis: radioiodine does not prevent development of atrial fibrillation): a. 12-lead ECG: on T=0, T=2 and T=5 years; b. Holter monitoring (24 hour): mean 24-hour heart rate, number of PAC and VES: on T=0, T=2 and T=5 years. 4. Changes in bone mineral density (null-hypothesis: radioiodine does not prevent deterioration of BMD): DEXA (Hologic or Lunar) L1-L4 and (right) femoral neck): on T=0, T=2 and T=5 years. | — |
Contacts
Public ContactE.H. Hoogendoorn
Univerity Medical Center St Radboud, Department of Endocrinologie, huispost 531, P.O. Box 9101
Outcome results
None listed