A randomized controlled trial to evaluate the adjuvant effect of lithium on radioiodine treatment of hyperthyroidism.
OBJECTIVE
To evaluate the role of lithium (Li) as an adjuvant in radioiodine therapy of hyperthyroidism.


METHODS
A randomized controlled trial was carried out on 350 hyperthyroid patients with a mean follow-up period of 32.3 +/- 9.8 months (range, 12-60 months). The patients were randomized into two groups with 175 patients in each group: (1) radioiodine group (controls)-no lithium was given to these patients at any stage of their treatment and (2) radioiodine and lithium group (Li group)-lithium carbonate, 300 mg three times a day, for 3 weeks starting on the day of radioiodine administration. All patients were made euthyroid with antithyroid drugs prior to radioiodine therapy.


RESULTS
Mean age was 41.8 +/- 11.5 years (range, 18-71) in the control group and 41.8 +/- 12.2 years (range, 19-73) in the Li group. Mean first dose and cumulative dose of (131)I were 229 +/- 85 MBq and 326 +/- 204 MBq in controls and 233 +/- 110 MBq and 344 +/- 281 MBq in the Li group. Average number of radioiodine therapy administered was the same (1.4) in both groups. The cure rate (euthyroid plus hypothyroid) after the first dose of radioiodine in the control and the lithium groups was 68.4% and 68.9%, respectively (p = ns). The overall cure rate at the end of the study was also the same in both groups (96.7% and 96.3%, respectively). Even in patients with a rapidly discharging gland or in patients with a large goiter, no significant statistical difference was observed in radioiodine therapy outcome between the two groups. Ten percent of the patients complained of mild to moderate side effects of lithium.


CONCLUSIONS
The role of lithium as an adjuvant in radioiodine therapy of hyperthyroidism is insignificant.
Bal
C S
CS
Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India. csbal@hotmail.com
Kumar
Ajay
A
Pandey
R M
RM
D000293:Adolescent; D000328:Adult; D000368:Aged; D013956:Antithyroid Agents / Q000627:therapeutic use; D003131:Combined Modality Therapy; D005260:Female; D006042:Goiter / Q000473:pathology / Q000532:radiotherapy / Q000628:therapy; D006111:Graves Disease / Q000532:radiotherapy / Q000628:therapy; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications / Q000532:radiotherapy / Q000628:therapy*; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008094:Lithium / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D013961:Thyroid Gland / Q000473:pathology; D016606:Thyroid Nodule / Q000532:radiotherapy / Q000628:therapy; D016896:Treatment Outcome
D013956:Antithyroid Agents; D007457:Iodine Radioisotopes; D008094:Lithium