Cognitive assessment of working memory in depression in the elderly after the use of repetitive transcranial magnetic stimulation by the theta-burst method: a randomized, double-blind clinical trial

• Grant number: 22/15368-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: April 01, 2023
• End date: March 31, 2027
• Field of knowledge: Health Sciences - Medicine - Psychiatry
• Principal Investigator: Leandro da Costa Lane Valiengo
• Grantee: Bianca Silva Pinto
• Host Institution: Instituto de Psiquiatria Doutor Antonio Carlos Pacheco e Silva (IPq). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated scholarship(s): 25/00391-7 - Exploring the Effects of Transcranial Alternating Current Stimulation (tCAS): An Innovative Approach to Assessing Working Memory, BE.EP.DD

Abstract

Major Depressive Disorder (MDD) is a severe, recurrent and disabling psychiatric condition that is mainly characterized by depressed mood and anhedonia, and secondary symptoms such as cognitive deficits. However, even patients in whom conventional treatment improves depressive symptoms, cognitive performance may remain impaired compared to healthy individuals. Thus, other forms of treatment are necessary, such as non-invasive neuromodulation techniques that have been shown to be able to modulate the activity of the dorsolateral prefrontal cortex (CPFDL), also enabling performance improvement in cognitive functions. Repetitive transcranial magnetic stimulation (rTMS) is a non-pharmacological intervention used for the treatment of several neuropsychiatric conditions. Recently, a variant of rTMS, theta burst stimulation (TBS), can provide cortical excitation or inhibition depending on the applied parameters. Unlike conventional rTMS methods, TBS consists of the application of a series of pulses at 50Hz that has shown promising results in the treatment of neuropsychiatric conditions, in addition to being cognitively safe for adult subjects. However, studies with elderly patients are still scarce. Objective: To investigate the working memory of TBS in elderly people with MDD. Method: randomized, double-blind clinical trial. Working memory (TM) will be evaluated in 105 patients with moderate depression aged 60 years or older. All subjects will undergo two stimulation protocols (active TBS vs sham TBS), randomized and double-blind. The treatment consists of 23 TBS sessions, the first 20 sessions being daily (except weekends and holidays) for 4 weeks and biweekly for two weeks and one monthly. The n-back task will be used to assess TM before the TBS session at baseline, 4, 6, 8 and 12 weeks. To apply the task, the E-prime software will be used. In this task, the subject must press the "M" key when the letter presented was the same as the one presented two positions before (target) and for other letters they should position the "Z" key (non-target). Expected results: It is expected to find greater understanding of the mechanisms of MDD and the action of rTMS in improving TM deficits in geriatric MDD patients. Thus, the evaluation of the performance of TM may be, in the future, as a predictor in studies with elderly psychiatric patients. (AU)