Risk Perception in Drug-Dependent Adults With and Without Schizophrenia
Condition: Cocaine Dependence; Cannabis Dependence; Schizophrenia
MeSH terms: Cocaine-Related Disorders; Marijuana Abuse; Schizophrenia
Study type: Observational

Summary: 
      Background:

        -  Several studies of risk perception have demonstrated a common bias known as unrealistic
           optimism, in which individuals feel they are less likely than other people to experience
           unpleasant or harmful events in their lives, but more likely to experience pleasant or
           beneficial events.

        -  Previous research has indicated that individuals with schizophrenia have less of a sense
           of unrealistic optimism about adverse events than individuals without schizophrenia.
           However, research on risk perception in schizophrenia is sparse, primarily reporting on
           behaviors and decisions in the laboratory that likely are influenced by risk perception.

        -  Risk perception among substance users may be viewed in two separate categories:
           perception of vulnerability to adverse events and perception of vulnerability to
           negative outcomes associated with substance use. Research in both areas has yielded
           mixed results. Researchers are interested in studying the connections among
           schizophrenia, addiction, and risk perception in order to develop better drug use
           prevention and treatment programs for people with and without schizophrenia.

      Objectives:

      - To compare unrealistic optimism bias in people with and without schizophrenia and/or drug
      dependence, and its association with actual risky behavior.

      Eligibility:

        -  Individuals between 18 and 64 years of age who fall into one of the following study
           categories:

        -  diagnoses of both drug dependence (marijuana or cocaine) and
           schizophrenia/schizoaffective disorder

        -  diagnosis of drug dependence only (marijuana or cocaine)

        -  diagnosis of schizophrenia/schizoaffective disorder only

        -  healthy volunteers with no history of drug use or serious mental disorder

      Design:

        -  The study will require a single visit to the research center for a 5- to 6-hour session.

        -  Participants will complete questionnaires on medical and behavioral history, complete
           tests of thinking skills like memory and attention, complete a brief computerized
           decision-making task, and answer questions about risk perception.

        -  Participants will also provide urine samples and breath carbon monoxide measurements to
           test for recent use of tobacco and other substances.
    

Detailed description: 
      Background:

      Several studies of risk perception have demonstrated a common bias known as unrealistic
      optimism', in which individuals feel they are less likely than other people to experience
      unpleasant or harmful events in their lives, but more likely to experience pleasant or
      beneficial events. In a previous study, we showed that unrealistic optimism about adverse
      events in patients with schizophrenia was lower than in healthy controls.

      Objective:

      To compare unrealistic optimism bias in people with and without schizophrenia and/or drug
      dependence, and its association with actual risky behavior.

      Study Population:

      Adults with current diagnosis (DSM-IV criteria) of schizophrenia or schizoaffective disorder
      (n = 24), with current drug dependence (cannabis or cocaine) (n = 24), with both
      schizophrenia and drug dependence (n = 24), or healthy, non-drug-using controls (n = 24).

      Study Design:

      Subjects will have a single study visit, at which their psychiatric and substance use
      histories, current substance use (urine drug testing, expired breath CO), risk perception,
      risk-taking/impulsivity, sensation-seeking, insight, history of risky behavior, and cognitive
      function will be assessed.

      Outcome Measures:

      Scores on Risk Perception Questionnaire, Balloon Analog Risk Task, short form self-report
      assessments of risk perception, risk-taking/impulsivity and sensation-seeking, Revised Life
      Orientation Scale, Self-Mastery Scale, Zuckerman-Kuhlman Personality Questionnaire,
      Repeatable Battery for the Assessment of Neuropsychological Status. South Oaks Gambling
      Screen-Revised, NORC DSM-IV Screen for Gambling Problems.

      Benefit:

      There is no direct benefit to subjects from study participation. Future benefits to society
      might be better understanding of risk perception biases associated with co-occurring
      substance abuse and schizophrenia, leading to development of more effective prevention and
      treatment programs and improved processes for obtaining informed consent.

      Risks:

      This study poses minimal risk to subjects, primarily boredom or anxiety from taking
      questionnaires and psychological tests and embarrassment from giving an observed urine
      specimen for drug testing.
    

Time perspective: Other
Keywords: Risk Taking; Schizophrenia; Drug Abuse/Dependence; Comorbidity; Impulsivity; Drug Abuse