Diffuse Non-toxic Goitre Therapy with Iodine Alone or with Combination of Iodine and Levothyroxine

Abstract

Aim: to assess the efficacy and tolerability of low-dose iodine therapy compared with the combination of iodine and levothyroxine in endemic goitre patients. Methods: 12-month prospective study was performed, in which 81 patients were randomized on two groups: Group 1 (n = 40) - KI (200 micrograms/day) and Group 2 (n = 41) - KI (100 mcg/day) + L-T4 (1.0 mcg/kg). Thyroid volume, TSH and Anti-TPO-Ab levels were evaluated at baseline, at 8 month of the treatment and at 12 month (4 month after the cessation of the therapy). Results: the significant decreasing of thyroid volumes was found in group 1 at 8 month compared with baseline (20.5 ml at baseline and 16,4 ml at 8 month р < 0.001). After the therapy cessation the further benefit of a sustained effect was demonstrated (16.4 ml at 8 month and 16.1 ml at 12 month, р = 0.31). Iodine-induced hypo- and hyperthyroidism were not observed. High Anti-TPO-Ab level was found in one of 31 patients (3%). In group 2 significant difference between thyroid volumes was found at 8 month compared with baseline (20,5 ml at baseline and 16.2 ml at 8 month р < 0.001). The sustained effect was revealed at least 4 month after the therapy cessation (16.2 ml at 8 month and 16.1 ml at 12 month, р = 0.77). One man had iodine-induced subclinical hyperthyroidism. Anti-TPO-Ab was not detected in this group. No significant difference between thyroid volume decreasing, TSH and Anti-TPO-Ab levels in two comparable groups was observed. Conclusion: KI alone (200 mcg/day) or the combination of L-T4 (1.0 mcg/kg) and KI (100 mcg/day) are equally effective and tolerable for endemic goitre therapy.