Data suggest that there is a greater cognitive benefit for patients with higher levels of baseline neurological disability treated with the training and transcranial direct current stimulation.
The pairing of online adaptive cognitive training with transcranial direct current stimulation (tDCS) as an at-home intervention strategy was feasible in treatment of multiple sclerosis (MS), a recent study found. Investigators, who presented data at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2022, February 24-26, in West Palm Beach, Florida, further observed a greater cognitive benefit in patients with higher levels of baseline neurological disability, when compared with those with lower levels.
Led by Leigh E. Charvet, PhD, professor, department of neurology, New York University Grossman School of Medicine, investigators enrolled patients with both MS and fatigue, measured by the Fatigue Severity Scale (FSS). Included patients did not have depression, measured by the Beck Depression Inventory (BDI) or severe cognitive impairment, measured by the Symbol Digit Modalities Test (SDMT). A total of 106 participants were included from the overall study sample of 116 participants, who were then randomized to either active (2.0 mA) or sham left anodal dorsolateral prefrontal cortextDCS paired with online adaptive cognitive training (aCT), completing 30 daily sessions of 20 minutes via Posit Science’s BrainHQ over a 6-week period.
Neurological development was evaluated at study entry using the Expanded Disability Status Scale (EDSS), with scores between 0.0 and 3.0 defined as low, and scores of 3.5 and 6.5 defined as high. At baseline and at the end of the intervention, the Brief International Cognitive Assessment in MS (BICAMS), and alternate test scores were converted to demographics-adjusted z scores then averaged for a composite score. Daily intervention sessions were completed at home, with remote supervision.
Cognitive assessments were completed at both time points, and investigators noted the high treatment fidelity, as 103 patients (99%) completed at least 25 of 30 tDCS+aCT sessions. Change in BICAMS score pre- and post-intervention was greater and improved in the active group (n = 55), with a mean change in BICAMS z score of 0.05 (SD, 0.54), when compared with the sham group (n = 51), with a mean change in BICAMS z score of –0.17 (SD, 0.46; P = .027). Additionally, active tDCS benefit was observed in both high and low EDSS strata, but there was a greater, significant change in BICAMS in the active vs sham comparison for patients with higher EDSS score (active: n = 23 [0.03; SD, 0.56]; sham: n = 21 [–0.41; SD, 0.34]; P = .004) when compared with those with lower EDSS score (active: n = 32 [0.07; SD, 0.53]; sham: n = 30 [0.00; SD, 0.47]; P = .595).
“Cognitive involvement is a common and troubling symptom for many people living with MS. Online aCT has demonstrated benefit if completed for extended periods (eg, 60 hours x 12 weeks),” Charvet et al wrote.1 “tDCSis a safe and tolerable method of noninvasive brain stimulation in which stimulation delivered during a training activity can potentiate outcomes. Our protocol of remotely supervised tDCS delivers multiple sessions of stimulation paired with training as a teleintervention. We tested the secondary cognitive outcomes in a blinded randomized sham-controlled clinical trial of active vs. tDCS paired with aCT for treatment of fatigue.”
In November 2020, Charvet sat down with NeurologyLive® to discuss the adoption of potential and validated digital and tele-based approaches for the treatment of MS. These approaches predate the onset of the COVID-19 pandemic, as repeat visits for this patient population can generate challenges. Calling attention to a positive trial investigating remotely delivered cognitive remediation in MS, Charvet said that patients did derive benefit and that several trials have shown the benefit of adding tDCS to therapies in order to boost and alleviate fatigue.2-4
“We have ongoing work to continue to understand that—dosing parameters is a big complication. Really careful study to refine its use is needed, but there have been very powerful signals that these things can work,” Charvet said.
“The discrepancy with my clinical practices—even though I know the research, and I tell people all the time to do this or do that. I'm just like any other provider in that it's very hard. For the patients, it's an uphill battle. For them to go home and adopt those things without the structure in place, it’s an uphill battle. My vision really would be some kind of coaching or structured support. That's what we have accessed, or provided, with the telerehabilitation with the tDCS because we're live with them at every session,” she added.