Faculty Bibliography

Background: Adaptable cognitive training interventions are accessible online from home for people with multiple sclerosis (PwMS), including for those with limited mobility, and have been shown to significantly improve cognition relative to control treatments. However, individual responsiveness to treatment is highly variable. Baseline clinical and MRI factors may contribute to this variability.
Objective(s): To determine whether specific baseline clinical and neuropathological MRI factors predict the success of online cognitive training in PwMS.
Method(s): 46 PwMS (30 RRMS, 16 PMS) were recruited for a 12-week home-based cognitive rehabilitation program. Subjects were recruited from a cohort of individuals with MRI previously collected (~2.3 years prior) for a larger study (Zivadinov, et al., 2017). Baseline and follow-up neuropsychological assessment included standard tests of cognition (SDMT, BVMTR, CVLT-II) and executive function (DKEFS), as well as clinical questionnaires. Participants were asked to complete 5 training sessions per week for approximately 50 minutes per session. Forward stepwise selection was applied using baseline clinical measures, including age, sex, EDSS, fatigue, depression, personality, disease course, and education, to predict longitudinal change in SDMT performance following rehabilitation from brain MRI measures. A separate, analogous regression analysis was applied to investigate MRI predictors of SDMT performance improvement, and included lateral ventricular volume (LVV), gray matter volume (GMV), and T2 lesion volume (T2LV).
Result(s): Disease course (RRMS vs PMS) was a statistically significant clinical predictor of improvement on SDMT performance following rehabilitation (beta=-0.336, p=0.026). The RRMS subgroup showed a 4.34 +/-5.74 point improvement (p< 0.0001), while there was no significant change in the PMS group (0.25 +/-4.73 points, p=0.835). Among MRI measures, baseline GMV was significantly related to improvement on SDMT performance (beta=0.367, p=0.014).
Conclusion(s): Remote cognitive rehabilitation therapy is more effective for individuals with RRMS, rather than those with PMS. Furthermore, increased baseline GMV is also predictive of greater cognitive improvement following rehabilitation

Background: Clinical observations and emerging studies suggest that African American (AA) people with multiple sclerosis (MS) tend to fare worse than their Caucasian American (CA) counterparts. Existing studies are limited by few AA participants and could often not evaluate other potential contributing factors.
Objective(s): To compare socio-economic and clinical characteristics of a large population of AA and CA people with MS.
Method(s): MS PATHS is a network of 10 large MS centers located in the United States (7) and Europe (3); standardized collection of socio-demographic characteristics, including self-reported racial identity, as well as clinical and disease information are acquired at least annually during routine clinic visits. We included US-based MS PATHS participants with self-reported AA and CA racial identities who provided socio-economic and MS characteristics. We compared AA vs. CA with respect to socio-economic and MS metrics including disability (via Patient Determined Disease Steps [PDDS]) and objective neurological outcomes (via walking speed, manual dexterity and processing speed) using generalized linear models, as appropriate. Models for PDDS and neurologic outcomes were adjusted for age, sex, disease subtype and duration, employment, insurance status.
Result(s): Of US-based eligible participants in MS PATHS, 909 (14%) identify as AAs while 5842 (86%) identify as CAs and were included in the analyses. Relative to CAs, AAs tended to be younger (Mean 49.7y [standard deviation; SD: 12.3y] vs. 45.6y [12.5]; p< 0.0001), have fewer years of education (14.8y [2.6] vs. 14.1y [2.8]; p< 0.0001), have Medicaid insurance (48% vs. 30%; P< 0.0001) and be currently on disability or not working (29% vs. 39%; p< 0.0001). AAs had a 58% multivariable-adjusted higher odds of severe vs. mild disability relative to CAs (OR: 1.56; 95% CI: 1.21-2.02). They also had significantly slower walking and manual dexterity speeds (multivariable-adjusted mean %difference [95% CI]: 25-foot walking speed: 10% slower [7%-13%]; manual dexterity: 7% slower [5%-9%]) and significantly lower processing speed scores (multivariable-adjusted mean difference-4.32 [-5.09-3.56]).
Conclusion(s): In this large sample of AA and CA people with MS, self-reported AA identity was associated with indicators of lower socio-economic status and with greater disease severity across a broad array of neurological assessments

OBJECTIVE:Cognitive impairment is a common symptom of multiple sclerosis (MS) that can lead to declines in daily functioning. Timed instrumental activities of daily living (TIADLs) have been useful to bridge between cognitive testing and real-world functioning in disorders such as Alzheimer's disease and other dementias. However, these have not been standardized for general use, and the tasks that are typically employed have not been sensitive to the detection of milder forms of cognitive deficits. We developed a test of ten TIADLs tasks to measure a broader range of functioning, entitled the "Test of Everyday Cognitive Ability" or TECA, and tested its utility in a diverse sample of participants with MS. METHOD/METHODS:TECA performance was characterized in n = 177 participants with MS and compared to healthy controls (n = 49). A subset from each group received repeated administration. In addition, all participants completed a standard battery of neuropsychological measures. RESULTS:TECA performances were significantly different between MS and control participants. Further, MS participants with cognitive impairment performed significantly slower relative to those MS participants without impairment. CONCLUSIONS:The TECA is a TIADLs assessment appropriate for use in those with MS as it includes a broad range of task difficulties, requires minimum motor involvement, and is sensitive to MS-related cognitive impairment. The TECA is a brief and repeatable test of TIADLs and its ease of administration makes it suitable for both clinical practice and research settings.

OBJECTIVE: To explore the efficacy of remotely-supervised transcranial direct current stimulation (RS-tDCS) paired with cognitive training (CT) exercise in participants with multiple sclerosis (MS). METHODS: In a feasibility study of RS-tDCS in MS, participants completed ten sessions of tDCS paired with CT (1.5 mA x 20 min, dorsolateral prefrontal cortex montage). RS-tDCS participants were compared to a control group of adults with MS who underwent ten 20-min CT sessions through the same remotely supervised procedures. Cognitive outcomes were tested by composite scores measuring change in performance on standard tests (Brief International Cognitive Assessment in MS or BICAMS), basic attention (ANT-I Orienting and Attention Networks, Cogstate Detection), complex attention (ANT-I Executive Network, Cogstate Identification and One-Back), and intra-individual response variability (ANT-I and Cogstate identification; sensitive markers of disease status). RESULTS: After ten sessions, the tDCS group (n = 25) compared to the CT only group (n = 20) had significantly greater improvement in complex attention (p = 0.01) and response variability (p = 0.01) composites. The groups did not differ in measures of basic attention (p = 0.95) or standard cognitive measures (p = 0.99). CONCLUSIONS: These initial findings indicate benefit for RS-tDCS paired with CT in MS. Exploratory analyses indicate that the earliest tDCS cognitive benefit is seen in complex attention and response variability. Telerehabilitation using RS-tDCS combined with CT may lead to improved outcomes in MS.

BACKGROUND:Neuropsychiatric disorders are a leading source of disability and require novel treatments that target mechanisms of disease. As such disorders are thought to result from aberrant neuronal circuit activity, neuromodulation approaches are of increasing interest given their potential for manipulating circuits directly. Low intensity transcranial electrical stimulation (tES) with direct currents (transcranial direct current stimulation, tDCS) or alternating currents (transcranial alternating current stimulation, tACS) represent novel, safe, well-tolerated, and relatively inexpensive putative treatment modalities. OBJECTIVE:This report seeks to promote the science, technology and effective clinical applications of these modalities, identify research challenges, and suggest approaches for addressing these needs in order to achieve rigorous, reproducible findings that can advance clinical treatment. METHODS:The National Institute of Mental Health (NIMH) convened a workshop in September 2016 that brought together experts in basic and human neuroscience, electrical stimulation biophysics and devices, and clinical trial methods to examine the physiological mechanisms underlying tDCS/tACS, technologies and technical strategies for optimizing stimulation protocols, and the state of the science with respect to therapeutic applications and trial designs. RESULTS:Advances in understanding mechanisms, methodological and technological improvements (e.g., electronics, computational models to facilitate proper dosing), and improved clinical trial designs are poised to advance rigorous, reproducible therapeutic applications of these techniques. A number of challenges were identified and meeting participants made recommendations made to address them. CONCLUSIONS:These recommendations align with requirements in NIMH funding opportunity announcements to, among other needs, define dosimetry, demonstrate dose/response relationships, implement rigorous blinded trial designs, employ computational modeling, and demonstrate target engagement when testing stimulation-based interventions for the treatment of mental disorders.