Can positive family factors be protective against the development of psychosis?

Genetic and environmental factors are both involved in the aetiology of psychotic disorders. The aim of this study was to assess if positive and negative environmental factors, together with psychotic family antecedents, are associated with the recent development of psychosis. We also investigated the interactions between family history of psychosis and positive and negative family environment. The sample comprised 110 children and adolescents, who had suffered a first psychotic episode and 98 healthy controls. All subjects were interviewed about their socioeconomic status, family history of psychosis and family environment (Family Environment Scale, FES). Early onset psychosis was significantly associated with a family history of psychosis. Family environment was perceived as more negative and less positive among patients than among controls. A negative family environment increased the risk of psychosis independently of the family history of psychosis. However, there was a significant protective effect of a positive family environment for persons with a family history of psychosis. This effect was not seen in subjects without a family history of psychosis. Therefore, our results support the importance of considering both family history of psychosis and family environment in the early stages of psychosis.