Transcranial Alternating Current Stimulation for Patients With Mild Alzheimer's Disease (TRANSFORM-AD)

Background: Alzheimer's disease (AD) is the most prevalent cause of dementia. Given the limited efficacy of pharmacological treatments, non-pharmacological approaches in AD are of great interest. In these approaches, brain stimulation technique is an important one, because of its potential to modulate cognitive functions in many neuropsychiatric diseases. Transcranial alternating current stimulation (tACS), as a neuromodulatory technique, oscillates a sinusoidal current at a chosen frequency to interact with the brain's natural cortical oscillations. Hypothetically, tACS would reduce cortical hyperactivity and induces cognitive improvement or delay cognitive decline in patients with AD. Objectives This double-blinded, randomized controlled trial evaluates the efficacy and safety of tACS in patients with mild AD. The second objective is to evaluate the effect of tACS on neural plasticity, which is assessed by structural and functional MRI, PiB-PET, and resting-state EEG. Patients and Methods The proposed study is a double-blinded, randomized controlled trial that will include 40 individuals with mild AD with positive findings in amyloid PET imaging or amyloid protein levels in CSF. The participants will be randomized to either a tACS group or a sham stimulation group. Both groups will undergo 30 one-hour sessions in 3 weeks (21 days). All the outcomes will be assessed at baseline, end of intervention and 3 months after the first intervention to measure long-term resilience of the effect.