Problem and Pathological Gambling in Schizophrenia: Exploring Links with Substance Use and Impulsivity

Abstract

High rates of both problem and pathological gambling (PPG) and substance-use disorders (SUDs) have been reported in schizophrenia, and yet PPG frequently goes undetected in clinical practice and unexamined in research. Here, we aimed to examine the relationship between PPG and SUDs in a large sample of patients across several factors related to both gambling and substance use, including poly-substance use. Additionally, delay discounting is a form of impulsivity known to positively associate with both PPG and SUDs and thought to underlie mechanisms of addiction in both contexts. We aimed to investigate the relationship between PPG and delay discounting in schizophrenia. 337 individuals with schizophrenia completed structured face-to-face interviews regarding gambling behaviors, substance use, and delay discounting. PPG in schizophrenia was associated with substance use, in particular with poly-substance use, and with delay discounting among males. Factors related to substance use were strongly linked with gambling in this sample, but not always with PPG more than recreational gambling. Our findings overall support the notions that multiple forms of gambling in schizophrenia are clinically relevant, that gambling may share common substrates with substance use, and that delay discounting represents a potential mechanism of this association in males.

Keywords: Addiction; Behavioral addiction; Delay discounting; Psychosis; Schizophrenia.