A high prevalence of organ-specific autoimmunity in patients with bipolar disorder.

BACKGROUND: In a previous study, we reported an increased prevalence of thyroperoxidase antibodies (TPOA) in patients with bipolar disorder. Here we report the prevalence of other organ-specific autoantibodies: H/K adenosine triphosphatase (ATPA), glutamic acid decarboxylase-65 (GAD65A), and GAD-67 (GAD67A). METHODS: ATPA, GAD65A, and GAD67A were determined (via a commercially available enzyme linked immunosorbent assay for ATPA, and a standardized radio immunoassays for GAD65A and GAD67A)in the sera of 239 patients with DSM-IV bipolar disorder, in 74 patients with DSM-IV schizophrenia, and in 220 healthy control subjects. RESULTS: The positivity prevalences for ATPA and GAD65A (but not GAD67A) were elevated in bipolar patients compared with those in healthy control subjects (11.7 vs. 6.1% and 11.3 vs. 2.6% respectively; p <.05). Schizophrenia patients did not show such statistically higher prevalence. The elevated prevalence of ATPA and GAD65A in bipolar disorder was associated with n