A randomized study of different radioiodine doses treatment hyperthyroidism

Abstract: Objective To compare clinical efficacy of ¹³¹I treatment for hyperthyroidism between fixed dose and calculated dose methods. Methods One hundred and forty eight patients with hyperthyroidism were randomly allocated fixed dose and calculated dose groups. Follow up was done 6 months post therapy, serum free triiodothyronine(FT₃), free thyroxin(FT₄) and thyroid stimulating hormone(TSH) were measured and following clinical outcome was monitored. Results The occurrence of hypothyroidism 6 months after ¹³¹I treatment in fixed dose and calculated dose groups was 31.1% and 28.4% respectively. There was no distinct difference between them(χ²=0-742, P=0.528). The cure rate was 93.3% and 85.2% respectively. There was no distinct difference between them(χ²=0.958, P=0.403). A good correlation was between clinical efficacy and thyroid mass(F=13.639, P=0.000). There was no distinct diflerence between the two groups of ages and 24 h radioactive iodine uptake(F=l.374, P=0.241; F:2.534,P=0.137). Conclusion The use of a fixed dose method simplifies the approach to treatment with potential cost savings.