High association of anticardiolipin antibodies with psychosis

Background: Lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) are autoantibodies that can be detected in plasma or serum of patients with autoimmune-related diseases. The presence of these autoantibodies has been associated with recurrent arterial and/or venous thromboembolism as well as with recurrent fetal loss and thrombocytopenia. In recent years, other medical conditions such as dementia, chorea, psychosis, migraine, and peripheral neuropathy have been associated with these autoantibodies. An adverse response to neuroleptic treatment was reported to be associated with the presence of autoantibodies, but these patients rarely developed clinical vascular manifestations. Method: We conducted a study of 34 unmedicated patients admitted to the hospital with acute psychosis in whom aCL and LA were examined before and after neuroleptic treatment to determine the presence of antibodies relative to the treatment condition. Results: 32% (11/34) of the unmedicated psychotic patients had antiphospholipid antibodies: we detected elevated titers of IgG-aCL isotype in 24% (8/34) of unmedicated patients (p <.02 compared with 20 normal controls, none of whom tested positive), and 9% (3/34) had LA. Twenty-two patients were followed up after medication; 31.8% (7/22) of these patients showed moderate titers of IgG-aCL (p <.28), and 18.2% (4/22) were LA positive. Altogether, antiphospholipid antibodies were detected in 40.9% (9/22) of the medicated patients. Conclusion: This study shows the increased incidence of LA and aCL antibodies in neuroleptic-treated psychotic patients and the possible association between psychosis and antiphospholipid antibodies.