EEG abnormalities and 3-year outcome in first episode psychosis

Objective: This study assesses the relationship of EEG to several aspects of 3 year symptomatic and functional outcome in first episode psychosis. Method: A total of 117 patients with first episode psychosis had their baseline EEG classified by modified Mayo Clinic criteria as normal, essentially normal or dysrhythmia. Socio-demographic variables, duration of illness and of untreated psychosis and premorbid adjustment were also recorded. Positive and negative symptoms of psychoses, depression, anxiety and global functioning were rated on entry and after 3 years of treatment. Results: Patients with a dysrhythmic EEG at entry into treatment showed significantly greater persistence in both positive and negative symptoms of psychoses as well as anxiety and depression over 3 years. These findings were independent of duration of untreated illness or premorbid adjustment. Conclusion: An abnormal baseline EEG in patients with first episode psychosis is associated with a poorer symptomatic outcome at 3-year follow-up.