Lifetime positive psychotic symptoms and subsequent risk of psychotic disorders in individuals with the 22q11.2 Deletion Syndrome

Abstract

Background: The 22q11.2 Deletion Syndrome (22q11DS) is a complex neuro-developmental disorder, which leads to a 25% increased risk of developing schizophrenia compared to approximately 1% chance in the general population. Investigating risk factors for developing psychotic disorders in the 22q11DS population could be an appropriate method to find out risk factors for developing psychotic disorders in the general population. In this study we focussed on the association between positive psychotic symptoms at any time point in life and the development of a full-blown psychotic disorder in adulthood, within the 22q11DS population. Methods: The data were analysed via a Binary Logistic Regression analysis, within 442 individuals (Mage = 17.72, SDage = 4.20): 34 individuals with a psychotic illness and 408 individuals without a psychotic disorder. Results: The findings indicate that the presence of positive psychotic symptoms is a significant risk factor for the subsequent development of a full-blown psychotic disorder, even after accounting for the effects of Baseline IQ and Verbal IQ decline. Discussion: This study underlines the importance of early screening of risk factors for developing a full-blown psychotic disorder. Further research could focus on investigating these risk factors in groups at risk for the psychotic disorder, early treatment of psychotic disorders and/or the severity of risk indicated by the SIPS, CAARMS or KSADS. Taken together, this research contributes to identifying risk factors of the development of psychotic disorders, most outstanding the presence of positive psychotic symptoms, in individuals with 22q11DS.