Risk Perception in Drug-Dependent Adults With and Without Schizophrenia

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.

• Participants in three patient groups will have a current diagnosis of schizophrenia (or schizoaffective disorder), drug dependence, or both. Healthy comparison participants will be free of either diagnosis. Psychiatric diagnoses will be based on DSM-IV criteria as determined by the Structured Clinical Interview for DSM-IV (SCID; First et al 1997), which will be administered in either a computerized version or in the standard interview format. Participants in all four groups will be 18-64 years old, of either gender and of any race/ethnicity. Specific inclusion and exclusion criteria for the participant groups are as follows:

• Group 1: Drug dependence with schizophrenia or schizoaffective disorder

Inclusion: Drug dependence; schizophrenia or schizoaffective disorder

Exclusions: mood disorder; obsessive-compulsive disorder (OCD)

• Group 2: Drug dependence without schizophrenia or schizoaffective disorder

Inclusion: Drug dependence.

Exclusions: schizophrenia or schizoaffective disorder; mood disorder; OCD.

• Group 3: Schizophrenia or schizoaffective disorder without drug dependence

Inclusion: DSM-IV schizophrenia or schizoaffective disorder.

Exclusions: mood disorder; OCD; use of illegal drugs more than 3 times in the previous month.

• Group 4: Healthy comparison participants

Exclusions: Any DSM-IV Axis I diagnosis (except simple phobia); use of illegal drugs more than 3 times in the previous month.

• Exclusions for all groups: History of neurological disease/condition (unrelated to schizophrenia or drug dependence) with ongoing cognitive sequelae; physical limitations (e.g., with hearing, vision or movement) that would prevent performance of computerized tasks; documented mental retardation.
• Substances of choice among drug-dependent participants (Groups 1 and 2) must be marijuana, cocaine or both (the commonest illegal drugs of abuse among patients with schizophrenia).