Lithium 유지치료 중 발생한 갑상선기능저하증의 임상지침을 위한 연구(I) -항갑상선 항체의 임상적 중요성 -

A Study for Clinical Guideline of Hypothyroidism During the Lithium Maintenance Therapy(I) - Clinical Importance of Antithyroid Antibody -

This study is a cross-sectional one for clinical reference of hypothyroidism during lithium maintenance therapy, focusing on anti thyroid antibody. Thyroid function including T3, T4，TSH, thyroid microsomal antibody, and thyroglobulin antibody were evaluated in 60 patients, given the diagnosis of bipolar disorder by DSM-III-R criteria. Thirty-five patients had never previously received lithium and the remaining 25 patients were on chronic lithium treatment(mean 22 months). A visible or palpable goiter was not found in any patient. No case of symptomatic hypothyroidism was observed, but subclinical hypothyroidism was present in 16% of patients on lithium, conpmared with 5.7% in the pre-lithium group. The prevalence of anti thyroid antibody was 32% in the lithium group, and 8.6% in the pre-lithium group. The difference of prevalena rate was statistically significant(p 0.05). In antibody- positive lithium-treated patients, the mean age was 41 years and the prevalance of thyroid antibody was higher in women. And the subclinical hypothyroidism was more prevalent in antibody-positive patients than in antibody-negative patients. But, the prevalence of antithyroid antibody did not significantly correlate with the duration of lifhium treatment in this study. This study shows that the thyroid function test including microsomal antibody and thyroglobulin antibody is very important for the early detection of the hypothyroidism when treating bipolar patients with lithium.