Transcranial Alternating Current Stimulation in Lewy Body Dementia

Interventional Study to Evaluate the Effectiveness of Transcranial Alternating Current Stimulation (tACS) on Cognitive Performance in Patients With Lewy Body Dementia

The aim of the study is to evaluate the safety, feasibility, clinical and biological efficacy, and predictors of efficacy of an intervention consisting of transcranial alternating current stimulation (tACS) in patients with Lewy Body Dementia (DLB).

In neurodegenerative diseases, like DLB, the process of neurodegeneration is accompanied by a significant alteration in oscillatory activity.

tACS is a neurophysiological method of non-invasive modulation of the excitability of the central nervous system that uses a mild electrical current. Recent studies have demonstrated the safety and efficacy of this method in modulating the natural brain oscillation frequencies underlying multiple cognitive processes, such as verbal memory, perception, and working memory. Preliminary data show that single stimulation with occipital α-tACS results in a significant improvement in visuospatial abilities and executive functions in patients wih DLB.

The study is double blind, randomised and placebo-controlled, participants will be randomised into two groups: group 1, participants will receive real tACS for 2 weeks, from Wednesday to Tuesday (5 sessions/week, lasting approximately 60 minutes each); and group 2, participants will receive placebo tACS for 2 weeks (5 sessions/week, lasting approximately 60 minutes each).

Visits will take place at the beginning of the study (T00), after 2 weeks (T02), and 12 weeks (T12, follow-up). During each visit, participants undergo the following procedures: (i) blood sampling, (ii) clinical and neuropsychological assessment, (iii) EEG, and (iv) TMS-EEG. The occurrence of adverse events will be monitored throughout the duration of the study. Specific biomarker analyses will be performed on the blood samples to study the pathophysiological mechanisms of the disease and the effect of the experimental intervention.

Inclusion Criteria:

• Male or female subjects aged over 18 at the time of signing the informed consent form;
• Presence of a clinical diagnosis of Lewy body dementia according to clinical criteria (McKeith et al., 2017)

Exclusion Criteria:

• Age younger than that stated in the inclusion criteria;
• Incapacity to understand;
• Contraindications for tACS and TMS: patients with cardiac pacemakers and metal implants that are not compatible with electric or magnetic fields, history of epilepsy, current pregnancy (Safety questionnaire)