Cognitive Behavioral Therapy (CBT) Study Evaluating the Updating of Persecutory Beliefs

The purpose of this study is to examine how Bayesian belief updating changes throughout psychotherapeutic treatment for persecutory delusions. Specifically, individuals with a psychotic disorder diagnosis who endorse both a current persecutory delusion with strong conviction and significant worry will be recruited and randomized to receive either a CBT-based worry intervention for persecutory delusions or an active control condition (befriending therapy). The investigators will examine: 1) whether belief updating parameters change as delusion severity changes, 2) whether CBT contributes to greater change in belief updating parameters than befriending therapy, and 3) whether neural correlates of belief updating parameters, as measured using functional magnetic resonance imaging (fMRI), predict treatment response.

Study Overview

• Status: Completed
• Conditions: Schizophrenia; Psychosis; Persecutory Delusion
• Intervention / Treatment: Behavioral: Worry Intervention; Behavioral: Befriending

• Study Type: Interventional
• Enrollment (Actual): 62
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Nashville, Tennessee, United States, 37212
      • Vanderbilt University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Men and women age 18 - 65.
2. Communicative in English.
3. Premorbid Intelligence >79 (WTAR)
4. Provide voluntary, written informed consent.
5. Physically healthy by medical history.
6. Weight <300 lbs
7. Stable medication regimen over at least the past two weeks, including the use of either an oral or intramuscular administration of an antipsychotic medication.
8. Diagnosis of a non-affective psychotic disorder (schizophrenia, schizoaffective disorder, schizophreniform disorder, delusional disorder, brief psychotic disorder, psychosis NOS) confirmed by Structured Clinical Interview for Diagnostic and Statistical Manual (DSM)-5 (SCID) or diagnostic interview with a trained clinician.
9. A persecutory delusion scoring at least a 3 on the conviction scale of the Psychotic Symptoms Rating Scale (PSYRATS) that had persisted for at least two weeks and that was not considered the direct result of substance use
10. A clinically significant level of worry, as shown by a score of at least 44 on the Penn State Worry Questionnaire (PSWQ).

Exclusion Criteria:

1. Age less than 18 or greater than 65.
2. Not communicative in English.
3. Premorbid IQ < 79 (WTAR)
4. Unable to provide written informed consent.
5. Current medical or neurological illness.
6. History of severe head trauma.
7. Weight >300 lbs
8. Primary diagnosis of alcohol or substance use disorder or personality disorder
9. Conditions that preclude fMRI scanning (as defined in the fMRI Screening Form)
10. Subjects who are actively involved with individual cognitive therapy (Past experience with individual therapy is not an exclusion)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Worry Intervention; The Worry Intervention uses cognitive-behavioral therapy (CBT) techniques to support the patient in reducing the amount of time they worry throughout the week. It is an 8-week manualized treatment with 5 modules. Each session is 45-60 minutes.	Behavioral: Worry Intervention; The worry intervention is weekly individual therapy with a trained therapist
Active Comparator: Befriending; Befriending therapy controls for the general factors of therapy (warmth, engagement) without any 'active' interventions. Individuals in the befriending arm will spend sessions talking with the therapist about things that interest them. It will also be conducted over 8-weeks with 45-60 minute sessions.	Behavioral: Befriending; The worry intervention is weekly individual therapy with a trained therapist

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Computational Parameters of Belief Updating as Measured During a Probabilistic Reversal Learning Task	change in computational parameters after intervention	Baseline, 4 weeks, 8 weeks, 24 weeks
Change in Delusion Severity Utilizing the Change in Psychotic Symptoms Rating Scale (PSYRATS)	The change in the Delusions subscale total of the Psychotic Symptoms Rating Scale (PSYRATS) from Baseline to Week 24. The Delusions subscale is a composite score of 6 items each rated from 0-4 with 4 indicating more severe symptomology. The Delusions subscale has a possible range of 0-24.	Baseline, 4 weeks, 8 weeks, 24 weeks
Change in Neural Correlates of Belief Updating Parameters	Change in blood oxygen dependent level (BOLD) signal after intervention	Baseline, 8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Baseline Neural Predictors of Treatment Response	BOLD signal during belief updating task at baseline predicting treatment response	Baseline
Resting-State Predictors of Treatment Response	resting-state connectivity of functional networks predicting treatment response	Baseline

Collaborators and Investigators

• Sponsor: Vanderbilt University Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): March 30, 2021
• Primary Completion (Actual): May 29, 2024
• Study Completion (Actual): May 29, 2024

Study Registration Dates

• First Submitted: February 5, 2021
• First Submitted That Met QC Criteria: February 5, 2021
• First Posted (Actual): February 10, 2021

Study Record Updates

• Last Update Posted (Actual): August 15, 2024
• Last Update Submitted That Met QC Criteria: August 14, 2024
• Last Verified: August 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Behavioral Symptoms; Mental Disorders; Schizophrenia Spectrum and Other Psychotic Disorders; Schizophrenia; Delusions
• Other Study ID Numbers: 201882

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No