Transcranial Alternating Current Stimulation (tACS) Combined With Cognitive Training in Alzheimer's Disease

Summary

The aim of the study is to evaluate the clinical and biological efficacy, as well as predictors of efficacy, of a home-based intervention combining transcranial alternating current stimulation (tACS) with individualized computerized cognitive training in patients with mild Alzheimer's disease (AD). In neurodegenerative diseases, including AD, neurodegeneration is accompanied by alterations in brain oscillatory activity. Restoration of these oscillations through neuronal entrainment has shown beneficial effects in animal models, while previous studies in patients with AD have demonstrated that gamma-frequency tACS applied over the precuneus is safe and well tolerated and is associated with improvements in cognitive performance and cholinergic function, as well as modulation of brain oscillatory activity. Cognitive rehabilitation may also improve memory performance in patients with mild AD. Based on this evidence, the present study investigates a multimodal approach combining gamma-tACS with individualized computerized memory training. The study is a multicenter, randomized, placebo-controlled, double-blind trial involving 30 participants with mild AD. Participants will be randomly assigned to one of two groups: Group 1 will receive real gamma-tACS for 8 weeks (5 sessions/week, 60 minutes/session) combined with cognitive training (2 sessions/week, 30 minutes/session); Group 2 will receive sham tACS according to the same schedule, combined with the same cognitive training. tACS will be applied over the precuneus. Treatment will initially be performed in the hospital and will subsequently be administered at home under remote supervision by the study team. Assessments will be performed at baseline (T00), after 8 weeks of treatment (T08), and at follow-up visits at 16 weeks (T16) and 24 weeks (T24) from baseline. At each time point, participants will undergo clinical and neuropsychological assessment, blood sampling, and transcranial magnetic stimulation (TMS). The occurrence of adverse events will be monitored throughout the duration of the study. The main objectives of the study are: 1) to evaluate the short- and long-term effects of the combined intervention on cognitive performance; 2) to investigate intervention-induced changes in biological markers of neurodegeneration, inflammation, and synaptic function; 3) to evaluate the effects of the intervention on cholinergic transmission through the TMS short-latency afferent inhibition (SAI) measure; and 4) to investigate potential predictors of treatment efficacy.

Interventions

• Transcranial Alternating Current Stimulation · DEVICE

  40 at-home sessions (5 days/week for 8 weeks), each consisting of the application of tACS (real, 40 Hz) applied over the precuneus for a duration of 60 minutes each.

• Sham Transcranial Alternating Current Stimulation · DEVICE

  40 at-home sessions (5 days/week for 8 weeks), each consisting of the application of sham tACS applied over the precuneus for a duration of 60 minutes each. The electrode placement will be identical to that used for real stimulation. However, the electrical current will be automatically interrupted approximately 5 seconds after the start of stimulation, making it impossible for the participant to distinguish between sham and real stimulation.

• Individualized Computerized Memory Training · BEHAVIORAL

  Participants will receive individualized computerized memory training for 8 weeks (2 sessions/week, 30 minutes/session) through synchronous telerehabilitation. The memory training will be individualized based on each participant's performance on the Face-Name Association Task (FNAT) and will use an errorless learning approach.

Published eligibility criteria

Verbatim from the registry. Only the site can decide how these apply to a specific patient.

Inclusion Criteria:

Patients:

* Male or female participants aged ≥18 years at the time of signing the informed consent form;
* Clinical diagnosis of mild Alzheimer's disease (AD) according to current clinical criteria;
* Availability of a caregiver who can assist the participant and who has successfully completed the required training for the use of the device at home.

Caregivers:

* Male or female caregivers aged ≥18 years;
* Compliance with participation in the in-hospital training;
* Mini-Mental State Examination (MMSE) score \>27/30.

Exclusion Criteria:

* Age below that specified in the inclusion criteria;
* Inability to understand;
* Contraindications to tACS and TMS (e.g., presence of a cardiac pacemaker or metallic implants incompatible with electrical or magnetic fields, history of epilepsy, or current pregnancy, as assessed using the safety questionnaire).

Sites (2)

• IRCCS Istituto Centro San Giovanni Di Dio - Fatebenefratelli, Brescia, Brescia · Recruiting
• IRCCS S. Maria Nascente - Fondazione Don Carlo Gnocchi, Milan, Italy · Not yet recruiting