INS NYC 2024 Program

Poster	Poster Session 04 Program Schedule 02/15/2024 12:00 pm - 01:15 pm Room: Shubert Complex (Posters 1-60) Poster Session 04: Neuroimaging \| Neurostimulation/Neuromodulation \| Teleneuropsychology/Technology Final Abstract #51 FDA-Approved Medications for Alzheimer’s Clinical Syndrome Do Not Interfere with Cognitive Improvement after Noninvasive Brain Stimulation Jessica Helphrey, UT Southwestern Medical Center, Dallas, United States John Hart, UT Dallas, Dallas, United States Matthew Peters, Johns Hopkins Medical Institution, Baltimore, United States Shawn McClintock, UT Southwestern Medical Center, Dallas, United States Vishal Thakkar, UT Southwestern Medical Center, Dallas, United States Laura Lacritz, UT Southwestern Medical Center, Dallas, United States C. Munro Cullum, UT Southwestern Medical Center, Dallas, United States Christian LoBue, UT Southwestern Medical Center, Dallas, United States Category: Neurostimulation/Neuromodulation Keyword 1: dementia - Alzheimer's disease Keyword 2: neuromodulation Keyword 3: cognitive functioning Objective: High-Definition Transcranial Direct Current Stimulation (HD-tDCS) is a non-invasive brain stimulation technique being explored as a potential new therapy for the Alzheimer’s Clinical Syndrome (ACS). Prior studies on the underlying mechanism for HD-tDCS have found that motor-evoked responses can be disrupted by use of certain pharmacological therapies often used for ACS, such as acetylcholinesterase inhibitors (AcHEI’s) and NMDA-receptor antagonists. While these FDA-approved medications have limited effectiveness, they are commonly used and it is unclear whether they may have a similar disruptive effect for cognitive outcomes from HD-tDCS in ACS. The purpose of this study was to evaluate if FDA-approved medication for ACS may alter the likelihood for a cognitive response to HD-tDCS treatment in individuals with ACS and mild cognitive impairment (MCI). Participants and Methods: Twenty-six individuals (M age = 69.42; 34.61% female, 58% ACS, 42% MCI) from two ongoing parallel randomized controlled trials underwent neuropsychological testing before and after multiple sessions of active HD-tDCS over the prefrontal cortex (10 treatments lasting 20-minutes each over 2 weeks; current intensity of 1 or 2mA). Neuropsychological testing assessed verbal learning and memory (Rey Auditory Verbal Learning Test or Hopkins Verbal Learning Test - Revised), visual learning and memory (Brief Visuospatial Memory Test - Revised), language (phonemic and categorical fluency), and executive function (Trail Making Test, DKEFS or Stroop Color Word). Neuropsychological performance was examined to dichotomize individuals into groups of being a responder or non-responder to HD-tDCS. A response was defined as improvement on two or more neuropsychological test scores by a T-score of at least 10 points. A binary logistic regression was performed to evaluate whether taking an FDA-approved medication predicted being a non-responder vs responder. Results: Eight individuals (M age = 69.13; 37.5% female, 6 with ACS; 2 with MCI) were identified as responders to HD-tDCS, and 7 were taking an ACS-related medication. Specifically, 4 individuals (2 ACS, 2 MCI,) were taking an AcHEI and 3 with ACS were concurrently taking an AcHEI with an NMDA-receptor antagonist. Of the 18 non-responders, eight individuals (4 with ACS; 4 with MCI) were taking an AcHEI and 3 individuals (with ACS) were concurrently taking an AcHEI with an NMDA-receptor antagonist, while 7 (2 ACS; 5 MCI;) were not taking any ACS-related medications. The binary logistic regression revealed that use of a medication for ACS was not significantly related to and had no predictive value for response to HD-tDCS (β = -1.94, p = 0.203). Conclusions: These preliminary findings suggest that taking a stable regimen of AcHEI or NMDA-receptor antagonists, two commonly prescribed pharmacological agents for ACS, does not prevent HD-tDCS associated cognitive outcomes in ACS and MCI. While neurophysiological studies of motor function have provided important insights about the mechanisms underlying HD-tDCS and the possible interference from medications, the current findings suggest that this may not generalize to cognitive response, and larger samples may be useful to further illuminate this relationship.

Poster

02/15/2024
12:00 pm - 01:15 pm
Room: Shubert Complex (Posters 1-60)

Poster Session 04: Neuroimaging | Neurostimulation/Neuromodulation | Teleneuropsychology/Technology

Final Abstract #51

FDA-Approved Medications for Alzheimer’s Clinical Syndrome Do Not Interfere with Cognitive Improvement after Noninvasive Brain Stimulation

Jessica Helphrey, UT Southwestern Medical Center, Dallas, United States
John Hart, UT Dallas, Dallas, United States
Matthew Peters, Johns Hopkins Medical Institution, Baltimore, United States
Shawn McClintock, UT Southwestern Medical Center, Dallas, United States
Vishal Thakkar, UT Southwestern Medical Center, Dallas, United States
Laura Lacritz, UT Southwestern Medical Center, Dallas, United States
C. Munro Cullum, UT Southwestern Medical Center, Dallas, United States
Christian LoBue, UT Southwestern Medical Center, Dallas, United States

Category: Neurostimulation/Neuromodulation

Keyword 1: dementia - Alzheimer's disease
Keyword 2: neuromodulation
Keyword 3: cognitive functioning

Objective:

High-Definition Transcranial Direct Current Stimulation (HD-tDCS) is a non-invasive brain stimulation technique being explored as a potential new therapy for the Alzheimer’s Clinical Syndrome (ACS). Prior studies on the underlying mechanism for HD-tDCS have found that motor-evoked responses can be disrupted by use of certain pharmacological therapies often used for ACS, such as acetylcholinesterase inhibitors (AcHEI’s) and NMDA-receptor antagonists. While these FDA-approved medications have limited effectiveness, they are commonly used and it is unclear whether they may have a similar disruptive effect for cognitive outcomes from HD-tDCS in ACS. The purpose of this study was to evaluate if FDA-approved medication for ACS may alter the likelihood for a cognitive response to HD-tDCS treatment in individuals with ACS and mild cognitive impairment (MCI).

Participants and Methods:

Twenty-six individuals (M age = 69.42; 34.61% female, 58% ACS, 42% MCI) from two ongoing parallel randomized controlled trials underwent neuropsychological testing before and after multiple sessions of active HD-tDCS over the prefrontal cortex (10 treatments lasting 20-minutes each over 2 weeks; current intensity of 1 or 2mA). Neuropsychological testing assessed verbal learning and memory (Rey Auditory Verbal Learning Test or Hopkins Verbal Learning Test - Revised), visual learning and memory (Brief Visuospatial Memory Test - Revised), language (phonemic and categorical fluency), and executive function (Trail Making Test, DKEFS or Stroop Color Word). Neuropsychological performance was examined to dichotomize individuals into groups of being a responder or non-responder to HD-tDCS. A response was defined as improvement on two or more neuropsychological test scores by a T-score of at least 10 points. A binary logistic regression was performed to evaluate whether taking an FDA-approved medication predicted being a non-responder vs responder.

Results:

Eight individuals (M age = 69.13; 37.5% female, 6 with ACS; 2 with MCI) were identified as responders to HD-tDCS, and 7 were taking an ACS-related medication. Specifically, 4 individuals (2 ACS, 2 MCI,) were taking an AcHEI and 3 with ACS were concurrently taking an AcHEI with an NMDA-receptor antagonist. Of the 18 non-responders, eight individuals (4 with ACS; 4 with MCI) were taking an AcHEI and 3 individuals (with ACS) were concurrently taking an AcHEI with an NMDA-receptor antagonist, while 7 (2 ACS; 5 MCI;) were not taking any ACS-related medications. The binary logistic regression revealed that use of a medication for ACS was not significantly related to and had no predictive value for response to HD-tDCS (β = -1.94, p = 0.203).

Conclusions:

These preliminary findings suggest that taking a stable regimen of AcHEI or NMDA-receptor antagonists, two commonly prescribed pharmacological agents for ACS, does not prevent HD-tDCS associated cognitive outcomes in ACS and MCI. While neurophysiological studies of motor function have provided important insights about the mechanisms underlying HD-tDCS and the possible interference from medications, the current findings suggest that this may not generalize to cognitive response, and larger samples may be useful to further illuminate this relationship.