A longitudinal study of thought disorder in manic patients.

To study the persistence of thought disorder in manic patients, 34 manic patients were compared with 30 schizophrenic and 30 nonpsychotic patients on four indexes of thought pathology at two phases of disorder: during the acute inpatient phase and one year after hospitalization. Patients were also compared with a control sample of 34 normal subjects. The data indicated that during the acute in hospital phase, both manic and schizophrenic patients were severely thought disordered; at follow-up, a subsample of manic patients showed severe thought disorder; despite the severe thought disorder found at follow-up in some manic and schizophrenic patients, both groups showed a significant reduction of thought pathology at follow-up; and there was a trend for a larger reduction of thought disorder in manic than in schizophrenic patients. The difference, however, was not significant when initial levels of severity were controlled.