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) inpatients with bipolar disorder. Here we report the prevalence of other organ-specific autoantibodies: HIK adenosine ttipbospbatase (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-117 bipolar disorder, in 74 patients with DSM-IV schizophrenia, and in 220 healthy control subjects. Results: The positivity prevalencesfor A TPA and GAD65A (but not GAD67A) were elevated in bipolarpatients compared with those in healthy control subjects 0 1. 7 vs. 6 1016 and 11.3 vs. 2.6016 respectively; p <. 05). Schizoph renia patients did not show such statistically h igher prevalence. The elevated prevalence of ATPA and GAD65A in bipolar disorder was associated with neither rapid cycling nor the use of lithium. Interestingly, the presence of GAD65A (and not that of TPOA and ATPA) tended to be associated with the activity of bipolar disorder. The level of 7POA was negatively correlated with the serum level of sIL-2R, a measure of T cell activation. Conclusion Bipolar disorder is associated with organ-specffic autoimmunity to the antigens 7PO, H/K ATPase, and GAD65.