SCHIZOTYPAL AND PARANOID PERSONALITY-DISORDER IN THE RELATIVES OF PATIENTS WITH SCHIZOPHRENIA AND AFFECTIVE-DISORDERS - A REVIEW

This review considers the possible familial relationship of schizotypa l and paranoid personality disorders (SPD, PPD) to schizophrenia (SCZ) and affective disorders (AD). There have been few controlled studies on familial risk of SPD and PPD based on direct semi-structured interv iews of relatives, blind to proband diagnosis. Three of six studies re ported increased familial risk of SPD for SCZ probands, but with consi derable variability in estimates of this risk. None of four studies re ported a significant relationship between AD and familial SPD. There i s substantial but less consistent evidence for a familial relationship between PPD and SCZ: three of six studies supported such a relationsh ip, but one large study reported increased familial risk of PPD for AD and not for SCZ probands. There is also some evidence that negative s ymptoms are most characteristic of SPD in relatives of SCZ probands. A lso discussed are issues concerning the adequacy of current criteria f or defining schizophrenia spectrum pathology, and of diagnostic method s in this area.