Repetitive transcranial magnetic stimulation for smoking cessation

Abstract

In Canada, 10.3% of the population smokes tobacco. 1 Each year, 8 million deaths worldwide are attributed to smoking. 2 Currently, 3 pharmacotherapies are approved for smoking cessation in Canada: varenicline, bupropion, and nicotine replacement therapy (NRT). Although these treatments are effective, many people do not respond to them, and relapse remains a problem. Recently, a repetitive transcranial magnetic stimulation (rTMS) device with a novel coil design (H-coil) was approved for smoking cessation by the US Food and Drug Administration (2020) and Health Canada (2022) (Figure 1). This is the first rTMS device approved for smoking cessation, but rTMS in various forms has been used for decades as an evidence-based treatment for depression. 3 What is rTMS?Repetitive transcranial magnetic stimulation is a noninvasive brain stimulation technique that generates magnetic fields using a magnetic coil to produce electrical currents in a targeted brain area. These currents allow for the facilitation (excitation) or suppression (inhibition) of neurons located beneath the coil, which results in changes in activity in the brain area. 4 The technique can be delivered with different types of coils; the most studied is the figure of 8. This coil is effective in stimulating superficial areas of the cortex, such as the dorsolateral prefrontal cortex. Alternative coils, such as H-coils, have been designed to stimulate deeper cortical regions, 5 which allow for targeting brain regions implicated in addiction, such as the insula, that are below the superficial cortex and not reached by figure-of-8 coils. 6