The significance of borderline and schizotypal overlap

Admission and mean 14-year follow-up Global Assessment Scale functioning were studied in 237 inpatients meeting DSM-III criteria for borderline (BPD) and schizotypal (SPD) personality disorders and compared to major affective disorder, schizophrenia and other diagnoses. BPD patients also meeting criteria for SPD functioned more poorly than other BPD or SPD patients at admission but improved their functioning at follow-up. Two BPD and SPD criteria which were associated with good follow-up functioning in BPD with SPD patients were found to predict poor admission functioning but good follow-up functioning in 18 of 237 former inpatients regardless of diagnosis.