Precuneus magnetic stimulation for Alzheimer’s disease: a novel TMS‐EEG based peronsalized therapeutic strategy

Abstract

AbstractBackgroundRepetitive transcranial magnetic stimulation (rTMS) may improve cognition in patients with Alzheimer’s disease (AD). rTMS therapy is currently limited by the relative short duration and the uncertainty on the most appropriate brain target area. AD patients primarily show alterations of the default mode network (DMN), a brain functional network for which the precuneus (PC) is a key node.MethodWe hypothesized that a long‐term 6 month course of rTMS applied over the precuneus could modify cognitive functions in patients with mild‐to‐moderate AD, by restoring cortical activity in the target network. To test this hypothesis we performed a randomized, double‐blind, sham‐controlled, phase II, 24‐weeks trial (NCT03778151). The primary outcome measure was change from baseline to week 24 of the Clinical Dementia Rating Scale–Sum of Boxes (CDR‐SOB). Secondary outcomes included score changes in the Alzheimer’s Disease Assessment Scale– Cognitive Subscale (ADAS‐Cog)11, Mini Mental State Examination (MMSE) and Alzheimer’s Disease Cooperative Study–Activities of Daily Living scale (ADCS‐ADL).Personalization of treatment and monitoring of cortical activity changes were refined by combining TMS and electroencephalography (TMS‐EEG).ResultWe found that AD patients treated with PC‐rTMS showed almost no decline in the CDR‐SB score, showing a clear advantage in terms of cognitive functions and functional abilities as compared to the sham group. rTMS induced in parallel remarkable changes in cortical activity, as demonstrated by TMS‐EEG recordings.Conclusion24 weeks of PC‐ rTMS may slow down cognitive and functional decline in AD patients by enhancing brain plasticity. Non‐invasive brain stimulation of the DMN could represent a novel therapeutic approach in AD patients.