A Pilot Study of Repetitive Transcranial Magnetic Stimulation for Treatment of Methamphetamine Use Disorders

Methamphetamine (MA) use can cause many serious adverse health consequences and is an important public health issue in Iowa, New Mexico, and Utah. In the 2017 Treatment Episode Data Set, 26% of substance use disorder treatment admissions from these states involved MA as the primary substance. MA-involved overdose deaths have been increasingly common in these states. Treatment for MA use disorder (MAUD) is primarily psychosocial. Rates of treatment induction and retention are poor, and relapse rates are high. There is a pressing need to identify effective interventions that enhance psychosocial treatments.

Transcranial magnetic stimulation (TMS) using either high frequency stimulation or intermittent theta burst stimulation is a non-invasive brain stimulation technique that effectively treats major depressive disorder and is considered safe, well-tolerated, and potent. TMS has increasingly been studied to treat addiction. The dorsolateral prefrontal cortex (DLPFC), a brain region implicated in regulatory processes related to executive function, emotion, motivation, and craving, is a common target for TMS. DLPFC stimulation using high frequency repetitive TMS has reduced craving in many studies of addictive disorders, including cocaine and MAUD. In addition to the DLPFC target, emerging evidence indicates that continuous theta burst stimulation (cTBS) delivered to the medial prefontal cortex (MPFC) during drug cue activation reduced craving and related brain activity in cocaine users. Despite these encouraging findings, no trials have reported on the efficacy of TMS for reducing MA use or preventing relapse. Clinical research on TMS for MAUD is sparse in the United States, and the limited studies of TMS in MAUD have been in experimental or closed treatment settings where effects on actual MA use are difficult to evaluate.

We are proposing a pilot study in 8 people with MAUD engaged in psychosocial treatment to explore the effects and tolerability of a four-week treatment protocol combining intermittent theta burst stimulation of the DLPFC with cTBS targeting the MPFC (dual-target TMS). We expect that this combined approach will enhance executive function and inhibitory control and reduce craving through separate but related mechanisms. We will evaluate clinical outcomes including symptoms and substance use, changes in functional connectivity measured via MRI and their relationship to treatment response, and changes in impulsivity as measured by performance on a response inhibition task. This project has the following specific aims:

Aim 1: Characterize changes in craving, depressive symptoms, anxiety symptoms, sleep quality, quality of life, and MA or other stimulant use over four weeks of dual-target TMS and eight weeks of subsequent follow-up.

Aim 2: Estimate changes in functional connectivity in the brain and response inhibition and selective attention in people with MAUD after four weeks of dual-target TMS.