[Improvement of the prognosis of Basedow's disease by using high doses of carbimazole]

The influence of synthetic antithyroid drug dosage on the course of Graves' disease was evaluated by comparing two groups of matched patients treated with carbimazole. Thirty-seven patients received a rapidly degressive treatment (60 mg/day initially rapidly reduced without replacement thyroid hormone therapy), and 36 patients received a prolonged treatment in high doses (60 mg daily for 6 months with progressive reduction of dosage over 5 months and replacement therapy). There was a highly significant difference in the actuarial curves of patients without relapse during 36 months: 82 per cent in patients with high doses, as against 38 per cent in patients with rapidly degressive treatment (log rank: chi 2 = 7.67, P less than 0.01). The anti-TSH receptor antibody titers decreased more rapidly in patients under prolonged treatment with high doses than in those with the rapidly degressive treatment. It is concluded that carbimazole in high doses is more immunosuppressive than in rapidly degressive doses and that it improves the prognosis of Graves' disease.