THE NEW-YORK HIGH-RISK PROJECT - PSYCHOSES AND CLUSTER A PERSONALITY-DISORDERS IN OFFSPRING OF SCHIZOPHRENIC PARENTS AT 23 YEARS OF FOLLOW-UP

Background: We herein present lifetime prevalence rates of psychoses a nd DSM-III-R cluster A personality disorders in sample A of the New Yo rk High-Risk Project, a prospective study following offspring of paren ts with schizophrenia (HRSz subjects) and affective illness (HRAff sub jects) and of psychiatrically normal parents (NC subjects) from midchi ldhood to adulthood. Methods: We interviewed the offspring in adulthoo d with the Schedule for Affective Disorders and Schizophrenia, Lifetim e Version, for Axis I disorders and the Personality Disorder Examinati on for Axis II disorders. Results: Lifetime prevalence rates (+/-SE) o f schizophrenia and unspecified psychosis were 11.1%+/-4.3% and 5.6%+3 .1%, respectively, in the HRSz group and 0% in the HRAff and NC groups . Rates of schizoaffective disorder subclassified as mainly schizophre nic, however, were highest in the HRAff group. Rates of psychotic affe ctive disorders did not differ between the HRSz and other groups. Age- corrected morbidity risks were similar to lifetime prevalence rates. R ates of the three cluster A personality disorders did not differ among the groups, but the combined rate was greater in the HRSz and HR4ff g roups than in the NC group. Conclusions: Our data strongly support a s pecific familial liability to narrowly defined schizophrenia that is n ot shared by families of probands with affective disorder. Schizoaffec tive disorder and cluster A personality disorders, however, occur in f amilies of both schizophrenic probands and probands with affective dis order. Psychotic affective disorders, which are not increased in HRSz subjects, do not appear to be an expression of the liability to schizo phrenia.