Long-Term Methimazole Treatment Benefits Children With Graves' Disease

By Reuters Staff

May 03, 2019

NEW YORK (Reuters Health) - Continuation of methimazole treatment beyond 24 months is associated with significantly higher cure rates in patients with Graves' hyperthyroidism, researchers from Iran report.

Among children and adolescents with diffuse toxic goiter treated with antithyroid drugs, side effects are common and relapse rates often exceed 70% after two years of treatment. Some studies have suggested that long-term treatment with anti-thyroid drugs is effective and safe in these patients.

Dr. Atieh Amouzegar and colleagues from Shahid Beheshti University of Medical Sciences, in Tehran, Iran, and colleagues evaluated the effects of long-term methimazole treatment in 48 young patients with Graves' disease in Tehran, an area of iodine sufficiency.

All patients were treated with methimazole for 18 to 24 months and were then randomly assigned to receive no additional treatment (the short-term group) or to continue receiving methimazole treatment (the long-term group). The long-term group received methimazole for a mean 109 months (range, 96-120 months).

The mean daily dose of methimazole was 5.17 mg at 22 months and, in the long-term group, 3.5 mg at the end of 96 to 120 months of methimazole treatment.

At the end of 48 months after methimazole withdrawal, the hyperthyroidism relapse rate was significantly higher in the short-term group (16/24, 67%) than in the long-term group (3/24, 12.5%), the researchers report in Pediatrics, online April 30.

Hyperthyroidism was cured one and four years after methimazole withdrawal in 92% and 88%, respectively, of patients in the long-term group, compared with only 46% and 33%, respectively, of patients in the short-term group.

In multivariate analyses, duration of methimazole treatment was the only factor that independently affected the outcome.

During the first six months of methimazole treatment, three adolescents experienced cutaneous reactions, but there were no serious complications. There were no adverse events related to methimazole treatment during long-term treatment with methimazole.

"Long-term methimazole treatment is a safe and effective treatment option for juvenile Graves' hyperthyroidism, having higher recovery rates than the short-term treatment," the researchers conclude.

Dr. Amouzegar did not respond to a request for comments.

SOURCE: https://bit.ly/2GWkCGd

Pediatrics 2019.