Neurocognitive Effects of Repetitive Transcranial Magnetic Stimulation With a 2-Coil Device in Treatment-Resistant Major Depressive Disorder.

BACKGROUND: Neurocognitive dysfunction is an understudied and undertreated aspect of psychiatric research and treatment. There is emerging evidence to suggest that repetitive transcranial magnetic stimulation (rTMS) may possess neurocognition-enhancing capabilities. METHODS: This study examined the neurocognitive data from a randomized, double-blind, sham-controlled trial of an investigational 2-coil rTMS device in antidepressant treatment or treatment-intolerant major depressive disorder patients. This device has the potential to stimulate deeper areas of the brain than the Food and Drug Administration-approved TMS devices, which primarily stimulate cortical brain areas and may therefore have different neurocognitive adverse effects. Patients received 20 daily rTMS treatments (10-Hz stimulation; either active or sham) with coil centers positioned over the left dorsolateral prefrontal cortex and dorsomedial prefrontal cortex. Neurocognitive safety was evaluated at baseline and within 72 hours of final treatment session with a computerized battery assessing aspects of attention and memory in 84 participants. RESULTS: There were no observed negative neurocognitive effects of the 2-coil rTMS device. A significant effect of active rTMS was observed on the quality of episodic memory. There were no observed effects for attention or working memory. Baseline quality of episodic memory predicted depression treatment response and remission, in that lower baseline episodic memory was associated with greater likelihood of depression response/remission. This was observed in logistic regression analyses controlling for treatment and baseline depressive symptoms. CONCLUSIONS: The 2-coil rTMS device is a cognitively safe treatment for treatment-resistant depression that may possess episodic memory-enhancing capabilities. Furthermore, baseline episodic memory may reflect an important predictor of subsequent depression treatment response/remission to rTMS.

rTMS with a two-coil array: Safety and efficacy for treatment resistant major depressive disorder.

BACKGROUND: Therapeutic repetitive Transcranial Magnetic Stimulation (rTMS) has emerged as a standard of care for individuals with major depressive disorder (MDD) who do not benefit from, or are unable to tolerate, antidepressant pharmacotherapy. Depth of stimulation is limited with currently approved figure-eight coils and larger coils capable of deeper penetration may be associated with loss of stimulation focality and undesired recruitment of motor cortex. A second generation 2-coil array rTMS system was designed to target converging brain pathways for potentially deeper prefrontal cortex stimulation. METHODS: A randomized, double-blind, sham-controlled trial examined the safety and efficacy of an investigational 2-coil rTMS device. Antidepressant treatment-resistant or treatment-intolerant MDD patients (n = 92) received 20 daily rTMS treatments with coil centers positioned over left dorsolateral prefrontal cortex (dlPFC) and dorsomedial prefrontal cortex (dmPFC). 10 Hz stimulation (maximum summated power for both coils ≤ 120% motor threshold) was delivered. Primary efficacy endpoint was change in HAMD-24 score from baseline to the conclusion of treatments. RESULTS: Data from n = 75 (per-protocol sample) showed significantly greater improvement (mean HAMD-24 change) over time for the active (n = 38) versus sham (n = 37) group after 20 sessions (F = 7.174; p = 0.008) and also at the one-month follow-up (F = 6.748; p = 0.010). Response rates were 55.3% (active) versus 32.4% (sham) (p = 0.063); remission rates were 26.3% versus 18.9% (p > 0.05). Other secondary outcomes were generally supportive. CONCLUSIONS: The results confirmed safety and acute efficacy of the 2-coil rTMS device. Despite modest sample size, primary outcome was clinically and statistically significant, and the effect size was comparable with those reported for regulatory trials with FDA-cleared devices.