Frontal P300 decrements, childhood conduct disorder, family history, and the prediction of relapse among abstinent cocaine abusers.

P300 event related brain potentials were studied in 49 cocaine dependent patients, abstinent for 1-5 months, and 20 healthy, non-drug-dependent controls. Patients were assigned to one of two subgroups based on the presence/absence of a DSM-IIIR diagnosis of antisocial personality disorder (ASPD). Analyses of P300s recorded during a visual selective attention task revealed reduced amplitudes at frontal electrode sites among patients with ASPD, relative to the ASPD negative patient and control groups. The frontal P300 decrement was significantly correlated with the number of childhood conduct disorder symptoms, but not with the presence/absence of a family history of alcoholism. A secondary analysis examined the relationship between P300 amplitude among cocaine dependent patients and their future behavior, i.e., relapse versus continued abstinence. Discriminant function analysis revealed that P300 amplitude alone accurately identified 70.6% of the patients who later relapsed, and 53.3% of the patients who did not.