Social class, family history and type of schizophrenia.

To date, there are numerous studies supporting a genetic model of schizophrenia. There is a paucity of studies, however, screening for a connection between family history of serious mental illness and deficit vs. nondeficit schizophrenia. The aim of the present study was to explore the association between family history, deficit vs. nondeficit schizophrenia and socioeconomic status (SES) of family of origin. Patients (N=437) from a United States psychiatric hospital were separated into deficit vs. nondeficit presentation and bifurcated into poor vs. nonpoor SES. Family history data were utilized to classify patients into subgroups characterized by serious mental illness within immediate family, within extended family, or no evidence of mental illness. Statistical testing was conducted using logistic regression analysis. SES of family of origin was significantly associated with schizophrenic subtype independently of family history, sex and race; specifically, poverty raised the risk of deficit schizophrenia. Family history of mental illness showed no net association, and no statistical interaction with poverty, in predicting risk of deficit schizophrenia.