Transcranial direct current stimulation (tDCS) for fatigue in multiple sclerosis

Abstract

BACKGROUND: The debilitating fatigue that patients with multiple sclerosis (MS) commonly experience during day-today living activities responds poorly to current therapeutic options. Direct currents (DC) delivered through the scalp (transcranial DC stimulation or tDCS) at weak intensities induce changes in motor cortical excitability that persist for almost an hour after current offset and depend on current polarity. tDCS successfully modulates cortical excitability in various clinical disorders but no information is available for MS related fatigue. OBJECTIVE: In this study we aimed to assess fatigue symptom after five consecutive sessions of anodal tDCS applied over the motor cortex in patients with MS. METHODS: We enrolled 25 patients with MS all of whom experienced fatigue. We delivered anodal and sham tDCS in random order in two separate experimental sessions at least 1 month apart. The stimulating current was delivered for 15 minutes once a day for 5 consecutive days. In each session the Fatigue Impact Scale (FIS) and the Back Depression Inventory (BDI) were administered before the treatment (baseline), immediately after treatment on day five (T1), one week (T2) and three weeks (T3) after the last tDCS session. RESULTS: All patients tolerated tDCS well without adverse events. The fatigue score significantly decreased after anodal tDCS in 65% of the patients (responders). After patients received tDCS for 5 days their FIS scores improved by about 30% and the tDCS-induced benefits persisted at T2 and T3. CONCLUSION: Our preliminary findings suggest that anodal tDCS applied over the motor cortex, could improve fatigue in most patients with MS.

Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines

“…The most common reported AEs were mild sensory phenomena that only occurred during stimulation at or near the electrodes (tingling, itching, phosphenes) that occurred in 253 (11.2%) subjects (e.g., Grecco et al, 2014a; Triccas et al, 2015). Transient events included skin irritation (75 subjects; 3.3%, Ferrucci et al, 2014; Triccas et al, 2015), issues with sleep or energy level, including sleepiness, fatigue, and insomnia (74 subjects; 3.3%; e.g., Lesniak et al, 2014; Murray et al, 2015), headache or nausea (56 subjects; 2.5%; Khedr et al, 2014; Kim et al, 2014), problems with concentrating (15 subjects; 0.7%; e.g., Wrigley et al, 2013), and neck pain (4 subjects; 0.2%; e.g. Straudi et al, 2016).…”

Beyond rehabilitation in MS: Insights from non-invasive brain stimulation

“…Bilateral tDCS over M1 has been applied for 5 days in 25 MS subjects with chronic fatigue in a cross-over study, with significant decrease in 65% of subjects after real versus 30% after sham stimulation; the effect persisted after 3 weeks. 29 Tecchio et al 30,31 obtained positive results applying anodal tDCS bilaterally over the whole somatosensory area. Anodal tDCS over the left dorsolateral prefrontal cortex (L-DLPFC) significantly ameliorated fatigue in two sham-controlled studies.…”

“…35 Finally, no effect on fatigue has been obtained from anodal tDCS of the right posterior parietal cortex. 32 Besides heterogeneity in clinical features of participants and stimulation site, inconsistent results obtained with tDCS may also be related to the relatively short intervention, from up to 5 days in most studies [29][30][31][32]34 to 20 days, 33 and the lack of a behavioral intervention.…”

Remotely Supervised Transcranial Direct Current Stimulation Increases the Benefit of At-Home Cognitive Training in Multiple Sclerosis

“…The most common subtype is relapsing-remitting and over half of these individuals transition to a progressive course; the remainder have a progressive course from the onset (31). tDCS warrants evaluation for potential clinical applications in MS (9,21,(32)(33)(34)(35)(36)(37)(38)(39). MS is associated with a high (>70%) rate of cognitive impairment.…”