Affiliations: Department of Neuropsychiatry, Assiut University Hospital, Assiut, Egypt
Correspondence:
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Corresponding author: Prof. Dr. Eman M. Khedr, Department of Neuropsychiatry, Faculty of Medicine, Assiut University Hospital, Assiut, Egypt. Tel.: +02 01005850632; Fax: +02 088 2333327; E-mail: emankhedr99@yahoo.com.
Abstract: Background:The exact mechanism of cognitive impairment in PD is not known. Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a possible treatment for cognitive impairment and to treat the motor symptoms in Parkinson’s disease (PD) where its effects seem additive to those of dopaminergic medications. Objective:In this pilot study we investigated whether repeated sessions of rTMS have an effect on measures of cognitive impairment in patients with PD dementia. Methods:33 patients with PD dementia were randomly assigned sham or real rTMS (2000 pulses; 20 Hz; 90% RMT; 10 trains of 10 s with 25 s between each train) over the hand area of each motor cortex (5 min between hemispheres) for 10 days (5 days/week) followed by 5 booster sessions every month for 3 months. Assessments included the Unified Parkinson’s Disease Rating Scale part III (UPDRS), Montreal Cognitive Assessment (MoCA); Mini Mental State Examination (MMSE), Clinical Dementia Rating Scale (CDR); Memory and Executive Screening (MES) and Instrumental activity of Daily Living (IADL). Event related potentials (P300) and cortical excitability were measured before treatment and after the last session. Results:There were no significant differences in the effects of rTMS between groups. Although rTMS improved motor function in the active group it had only a minor effect on two of the dementia rating scores (the MMSE and MoCA) but not the others (CDR and MES). There was also a reduction in the latency of the P300 in the active group. Conclusions:rTMS over M1 is useful for motor function and may have a small positive effect on cognition. However, better approaches for the latter are necessary, may be require multisite rTMS to target both motor and frontal cortical region.
Keywords: Parkinson’s disease, cognitive impairment, dementia, repetitive transcranial magnetic stimulations, Unified Parkinson’s Disease Rating Scale part III, Montreal cognitive assessment, Mini mental state examination, Clinical Dementia Rating, P300, cortical excitability parameters
