Effects of Repetitive Transcranial Magnetic Stimulation (rTMS) on Cannabis Use and Cognitive Outcomes in Schizophrenia

Summary

The high prevalence of cannabis and other substance use disorders are a major barrier to recovery in people with schizophrenia. Moreover, schizophrenia patients have significant deficits in cognitive function, which may be exacerbated by cannabis use. Complicating these problems is the lack of evidence-based treatments for co-morbid cannabis use disorders (CUDs) in schizophrenia; there are no established pharmacotherapies. Therefore, this study is investigating the effects of high-frequency (20Hz) repetitive transcranial magnetic stimulation (rTMS) on cannabis use disorder and cognitive function in patients with co-morbid schizophrenia/schizoaffective disorder. The proposed study would be the first randomized, double-blind, sham controlled trial of rTMS in patients with schizophrenia and co-morbid CUD. A total of N=40 schizophrenia smokers with co-morbid cannabis use disorder will be assigned to either active rTMS (N=20) or sham rTMS (N=20) as a treatment regimen of 5X/week treatment for four consecutive weeks. All participants will receive weekly behavioral therapy for 4 weeks. The investigators predict that active rTMS will be well-tolerated and superior to sham rTMS for the treatment of CUD in schizophrenia.

Conditions

• Repetitive Transcranial Magnetic Stimulation (rTMS)
• Schizophrenia
• Cannabis Use Disorder
• Cognition

Interventions

DEVICE

Repetitive Transcranial Magnetic Stimulation (rTMS)

On Day 1, the resting motor threshold (RMT) will be determined according to previous published methods \[Cardenas-Morales et al. 2013\] and the rTMS will be delivered at an intensity of 90% of the participant's RMT. rTMS will be administered at 20 Hz (25 trains, 30 pulses per train, 30 second intertrain interval).

DEVICE

Sham Repetitive Transcranial Magnetic Stimulation (rTMS)

On Day 1, the resting motor threshold (RMT) will be determined according to previous published methods \[Cardenas-Morales et al. 2013\] and the Sham rTMS will be delivered at an intensity of 90% of the participant's RMT. rTMS will be administered at 20 Hz with the B65 placebo coil (25 trains, 30 pulses per train, 30 second intertrain interval).

BEHAVIORAL

Weekly Counselling Session

In order to support participants in their abstinence plan, individual weekly sessions of supportive counselling will be administered over the course of the study on 1 time per week over 4 weeks (28 days of abstinence).

Sponsors & Collaborators

• Centre for Addiction and Mental Health

  lead OTHER

Principal Investigators

• Tony P George, MD, FRCPC · Centre for Addiction and Mental Health

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

55 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2017-06-01

Primary Completion

2021-06-30

Completion

2021-06-30

Countries

• Canada

Study Locations