Abstract
Antithyroid antibodies were measured in 58 patients with unipolar major depressive disorder. None of the patients had received prior lithium treatment. Five patients had antimicrosomal and antithyroglobulin antibodies. The prevalence rate of detectable antibody titers approximates that found in normal subjects. The presence of detectable antibody titers was not related to abnormal thyroid function tests. The implications of these findings are discussed.