Journal
SCHIZOPHRENIA RESEARCH
Volume 80, Issue 2-3, Pages 235-242Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.schres.2005.07.009
Keywords
dimensions; schizotypal; genetic; familiality; psychosis
Categories
Ask authors/readers for more resources
Background: Family studies have suggested that schizophrenia and bipolar disorders share some susceptibility factors. Schizotypal personality disorder (SPD) may be an intermediate phenotype common both to schizophrenia and bipolar disorders. We explored the familiality of schizotypal dimensions by comparing the magnitude of schizotypal dimensions between schizophrenic and bipolar relatives. We also looked for intra-familial resemblance for these dimensions and for an increased familial risk of schizophrenia and/or bipolar disorders associated with a particular schizotypal dimension. Methods: We used the Schizotypal Personality Questionnaire (SPQ) to study the three schizotypal dimensions (disorganization, negative and positive) in a sample of unaffected first-degree relatives of schizophrenic (N=85), psychotic bipolar (N=63) and bipolar (N=32) probands. Differences between groups were tested using a two-tailed t-test or ANOVA for continuous variables and a Chi-squared test for discrete variables. We used the intraclass correlation method to study the intra-familial correlation. Linear mixed models were used to measure the familial risk. Results: The disorganization dimension appears to be common to relatives of both schizophrenia and psychotic bipolar disorders, but not in the relatives of non-psychotic bipolar probands. This dimension also increases the familial risk of these two disorders. The negative dimension shows intra-familial resemblance (r=0.29), we failed to observe the expected familiality for the disorganized dimension. Conclusions: The shared nature of the disorganization dimension shown by a similar familial risk for schizophrenia and psychotic bipolar disorders suggests that same genetic background may underlie psychotic disorders. Although negative dimension is familial, it is not associated for an increased familial risk for both disorders. (c) 2005 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available