Cognitive Dysfunction in Persons with Chronic Spinal Cord Injuries

The role of clinical and demographic predictors for understanding the cognitive impairment in Spinal Cord Injury (SCI) patients

STUDY DESIGN

Using a cross-sectional design, we extracted sociodemographic and clinical data from 488 Spinal Cord Injury (SCI) patients during their initial assessment before receiving intensive rehabilitation treatment.

OBJECTIVES

The primary objectives of this study were to ascertain the prevalence of cognitive impairment in the study sample and specify the key clinical and demographic predictors of cognitive functioning in SCI patients.

SETTING

Lucy Montoro Rehabilitation Institute (LMRI), University of Sao Paulo, Sao Paulo, Brazil.

METHODS

We utilized independent univariate and multivariate regression models with the Montreal Cognitive Assessment (MoCA) scale, adapted for individuals with visual impairment. Moreover, we consider scores from the execution tasks (visuospatial/executive) as the dependent variable.

RESULTS

Our findings demonstrate that approximately 80% of the evaluated study sample exhibited cognitive impairment. Through the multivariate regression models, we show that several factors, including age, education, depression levels, and the use of analgesics and/or opioids, are significant predictors of total cognitive scores. These factors are independent of the clinical features associated with SCI, such as age, sex, education, and time since the injury.

CONCLUSIONS

The results indicate a high prevalence of significant cognitive impairment within the sample, with age, education, depression levels, and the use of analgesics and/or opioids emerging as the primary predictors of total cognitive scores, independent of the clinical features correlated to SCI. These findings hold significant implications for both clinical research and practice, offering valuable guidance for comprehensive management throughout hospitalization and rehabilitation.

Characterization of Sleep, Emotional, and Cognitive Functions in a New Rat Model of Concomitant Spinal Cord and Traumatic Brain Injuries

Traumatic injuries to the spinal cord or the brain have serious medical consequences and lead to long-term disability. The epidemiology, medical complications, and prognosis of isolated spinal cord injury (SCI) and traumatic brain injury (TBI) have been well described. However, there are limited data on patients suffering from concurrent SCI and TBI, even if a large proportion of SCI patients have concomitant TBI. The complications associated with this "dual-diagnosis" such as cognitive or behavioral dysfunction are well known in the rehabilitation setting, but evidence-based and standardized approaches for diagnosis and treatment are lacking. Our goal was to develop and characterize a pre-clinical animal model of concurrent SCI and TBI to help identifying "dual-diagnosis" tools. Female rats received a unilateral contusive SCI at the thoracic level alone (SCI group) or combined with a TBI centered on the contralateral sensorimotor cortex (SCI-TBI group). We first validated that the SCI extent was comparable between SCI-TBI and SCI groups, and that hindlimb function was impaired. We characterized various neurological outcomes, including locomotion, sleep architecture, brain activity during sleep, depressive- and anxiety-like behaviors, and working memory. We report that SCI-TBI and SCI groups show similar impairments in global locomotor function. While wake/sleep amount and distribution and anxiety- and depression-like symptoms were not affected in SCI-TBI and SCI groups in comparison to the control group (laminectomy and craniotomy only), working memory was impaired only in SCI-TBI rats. This pre-clinical model of concomitant SCI and TBI, including more severe variations of it, shows a translational value for the identification of biomarkers to refine the "dual-diagnosis" of neurotrauma in humans.

Psychological Screening, Standards and Spinal Cord Injury: Introducing Change in NHS England Commissioned Services

Psychologist resourcing across the United Kingdom (UK) spinal cord injury centres (SCICs) varies considerably, which has detrimentally impacted standardising service provision for people with spinal cord injuries/disorders (PwSCI/D) compared with other nations. This paper presents the outcome of a project involving the Spinal Cord Injury Psychology Advisory Group (SCIPAG) and NHS England Clinical Reference Group/SCI transformation groups to agree upon screening and standards and shares data from the National Spinal Injuries Centre (NSIC) and the Yorkshire and Midlands Regional SCICs. Inpatients completed the GAD-7, the PHQ-9, and the short form of the Appraisals of DisAbility: Primary and Secondary Scale (ADAPSSsf), assessing adjustment. A total of 646 participants were included, with 43% scoring above the clinical threshold on at least one of the measures on admission. A subset of 272 participants also completed discharge measures and 42% remained above the threshold on discharge, demonstrating sustained psychological need. This paper provides support for services to move to a screen-and-assessment model supplemented by referral options for those with changing needs or who present with difficulties outside the remit of screening. The findings also support the efficacy of universal screening across the system and consideration of screening and standards for psychological care by the wider psychology community.

Sexually dimorphic extracellular vesicle responses after chronic spinal cord injury are associated with neuroinflammation and neurodegeneration in the aged brain

BACKGROUND

Medical advances have made it increasingly possible for spinal cord injury (SCI) survivors to survive decades after the insult. But how SCI affects aging changes and aging impacts the injury process have received limited attention. Extracellular vesicles (EVs) are recognized as critical mediators of neuroinflammation after CNS injury, including at a distance from the lesion site. We have previously shown that SCI in young male mice leads to robust changes in plasma EV count and microRNA (miR) content. Here, our goal was to investigate the impact of biological sex and aging on EVs and brain after SCI.

METHODS

Young adult age-matched male and female C57BL/6 mice were subjected to SCI. At 19 months post-injury, total plasma EVs were isolated by ultracentrifugation and characterized by nanoparticle tracking analysis (NTA). EVs miR cargo was examined using the Fireplex® assay. The transcriptional changes in the brain were assessed by a NanoString nCounter Neuropathology panel and validated by Western blot (WB) and flow cytometry (FC). A battery of behavioral tests was performed for assessment of neurological function.

RESULTS

Transcriptomic changes showed a high number of changes between sham and those with SCI. Sex-specific changes were found in transcription networks related to disease association, activated microglia, and vesicle trafficking. FC showed higher microglia and myeloid counts in the injured tissue of SCI/Female compared to their male counterparts, along with higher microglial production of ROS in both injured site and the brain. In the latter, increased levels of TNF and mitochondrial membrane potential were seen in microglia from SCI/Female. WB and NTA revealed that EV markers are elevated in the plasma of SCI/Male. Particle concentration in the cortex increased after injury, with SCI/Female showing higher counts than SCI/Male. EVs cargo analysis revealed changes in miR content related to injury and sex. Behavioral testing confirmed impairment of cognition and depression at chronic time points after SCI in both sexes, without significant differences between males and females.

CONCLUSIONS

Our study is the first to show sexually dimorphic changes in brain after very long-term SCI and supports a potential sex-dependent EV-mediated mechanism that contributes to SCI-induced brain changes.

Myokines may target accelerated cognitive aging in people with spinal cord injury: A systematic and topical review

Persons with spinal cord injury (SCI) can suffer accelerated cognitive aging, even when correcting for mood and concomitant traumatic brain injury. Studies in healthy older adults have shown that myokines (i.e. factors released from muscle tissue during exercise) may improve brain health and cognitive function. Myokines may target chronic neuroinflammation, which is considered part of the mechanism of cognitive decline both in healthy older adults and SCI. An empty systematic review, registered in PROSPERO (CRD42022335873), was conducted as proof of the lack of current research on this topic in people with SCI. Pubmed, Embase, Cochrane and Web of Science were searched, resulting in 387 articles. None were considered eligible for full text screening. Hence, the effect of myokines on cognitive function following SCI warrants further investigation. An in-depth narrative review on the mechanism of SCI-related cognitive aging and the myokine-cognition link was added to substantiate our hypothetical framework. Readers are fully updated on the potential role of exercise as a treatment strategy against cognitive aging in persons with SCI.

The Montreal Cognitive Assessment (MoCA) in Neuro-Oncology: A Pilot Study of Feasibility and Utility in Telehealth and In-Person Clinical Assessments

Background

Cognitive impairments are a common burden for patients with primary CNS tumors. Neuropsychological assessment batteries can be too lengthy, which limits their use as an objective measure of cognition during routine care. The purpose of this study was to evaluate the feasibility and utility of the brief Montreal Cognitive Assessment (MoCA) in routine in-person and telehealth visits (as a result of the global COVID-19 pandemic) with neuro-oncology patients.

Methods

71 adults with primary CNS tumors completed MoCA testing in-person (n=47) and via telehealth (n=24). Patient-reported outcomes (PROs), including symptom burden and interference, perceived cognition, general health status, and anxiety and depression, were and correlation analysis were included in this study. Feasibility was assessed through a provider satisfaction questionnaire.

Results

Patients were primarily White (83%), college-educated (71%) males (54%) with high grade tumors (66%). The average total score on the MoCA administered in-person was 25 (range: 6-30), with 34% classified as abnormal, and the average total score via telehealth was 26 (range: 12-30), with 29% classified as abnormal. Providers reported satisfaction in using the MoCA during routine clinical care, both in-person and via telehealth. Lower MoCA scores correlated with worse symptom severity, KPS, age, education, and previous treatment.

Conclusions

The MoCA was feasible in clinical and telehealth settings, and its relationship to clinical characteristics and PROs highlight the need for both objective and patient-reported measures of cognition to understand the overall cognitive profile of a patient with a CNS tumor.

Latent Neuropsychological Profiles to Discriminate Mild Traumatic Brain Injury and Posttraumatic Stress Disorder in Active-Duty Service Members

OBJECTIVE

To determine whether cognitive and psychological symptom profiles differentiate clinical diagnostic classifications (eg, history of mild traumatic brain injury [mTBI] and posttraumatic stress disorder [PTSD]) in military personnel.

METHODS

US Active-Duty Service Members (N = 209, 89% male) with a history of mTBI (n = 56), current PTSD (n = 23), combined mTBI + PTSD (n = 70), or orthopedic injury controls (n = 60) completed a neuropsychological battery assessing cognitive and psychological functioning. Latent profile analysis was performed to determine how neuropsychological outcomes of individuals clustered together. Diagnostic classifications (ie, mTBI, PTSD, mTBI + PTSD, and orthopedic injury controls) within each symptom profile were examined.

RESULTS

A 5-profile model had the best fit. The profiles differentiated subgroups with high (34.0%) or normal (21.5%) cognitive and psychological functioning, cognitive symptoms (19.1%), psychological symptoms (15.3%), and combined cognitive and psychological symptoms (10.0%). The symptom profiles differentiated participants as would generally be expected. Participants with PTSD were mainly represented in the psychological symptom subgroup, while orthopedic injury controls were mainly represented in the high-functioning subgroup. Further, approximately 79% of participants with comorbid mTBI and PTSD were represented in a symptomatic group (∼24% = cognitive symptoms, ∼29% = psychological symptoms, and 26% = combined cognitive/psychological symptoms). Our results also showed that approximately 70% of military personnel with a history of mTBI were represented in the high- and normal-functioning groups.

CONCLUSIONS

These results demonstrate both overlapping and heterogeneous symptom and performance profiles in military personnel with a history of mTBI, PTSD, and/or mTBI + PTSD. The overlapping profiles may underscore why these diagnoses are often difficult to diagnose and treat, but suggest that advanced statistical models may aid in identifying profiles representing symptom and cognitive performance impairments within patient groups and enable identification of more effective treatment targets.

Future Perspectives in Spinal Cord Repair: Brain as Saviour? TSCI with Concurrent TBI: Pathophysiological Interaction and Impact on MSC Treatment

Traumatic spinal cord injury (TSCI), commonly caused by high energy trauma in young active patients, is frequently accompanied by traumatic brain injury (TBI). Although combined trauma results in inferior clinical outcomes and a higher mortality rate, the understanding of the pathophysiological interaction of co-occurring TSCI and TBI remains limited. This review provides a detailed overview of the local and systemic alterations due to TSCI and TBI, which severely affect the autonomic and sensory nervous system, immune response, the blood-brain and spinal cord barrier, local perfusion, endocrine homeostasis, posttraumatic metabolism, and circadian rhythm. Because currently developed mesenchymal stem cell (MSC)-based therapeutic strategies for TSCI provide only mild benefit, this review raises awareness of the impact of TSCI-TBI interaction on TSCI pathophysiology and MSC treatment. Therefore, we propose that unravelling the underlying pathophysiology of TSCI with concomitant TBI will reveal promising pharmacological targets and therapeutic strategies for regenerative therapies, further improving MSC therapy.