Cognitive function after spinal cord injury: A systematic review

Influence of Diabetes Mellitus on Neurological Recovery in Older Patients With Cervical Spinal Cord Injury Without Bone Injury: A Retrospective Multicenter Study

Study DesignRetrospective study.ObjectivesTo investigate the impact of diabetes mellitus on neurological recovery and determine the relationship between moderate-severe diabetes and neurological recovery in patients with cervical spinal cord injury (CSCI) without bone injury.MethodsA retrospective study was conducted on 389 consecutive patients aged ≥65 years with CSCI without bone injury across 33 medical institutes. The patients were divided into a nondiabetic group (n = 270) and a diabetic group (n = 119). Neurological outcomes were compared between the two groups through propensity score matching. The impact of moderate-severe diabetes (defined as hemoglobin A1c ≥ 7.0% or requiring insulin treatment) on neurological recovery was evaluated through multiple linear regression analysis.ResultsPropensity score matching revealed no significant differences between the diabetic and nondiabetic groups in terms of American Spinal Injury Association (ASIA) impairment scale grade and mean total ASIA motor scores (AMS) at 6 months post-injury. Multiple linear regression analysis indicated that age on admission (B = -0.34; 95% confidence interval [CI], -0.59 to -0.08; P = 0.01), dementia (B = -16.50; 95% CI, -24.99 to -8.01; P < 0.01), and baseline total AMS (B = -0.62; 95% CI, -0.72 to -0.51; P < 0.01) were negative predictors of neurological recovery at 6 months post-injury. The presence of moderate-severe diabetes did not influence neurological recovery at 6 months post-injury.ConclusionsDiabetic patients with CSCI without bone injury achieved improvements in neurological function comparable to those of nondiabetic patients. Moderate-severe diabetes did not affect neurological recovery in patients with CSCI without bone injury.

'Time is of the essence': upper-body aerobic exercise to improve cardiovascular health during inpatient rehabilitation within the first year following spinal cord injury - protocol for a randomised clinical trial

INTRODUCTION

Individuals with spinal cord injury (SCI) face heightened cardiovascular disease (CVD) risks. While general exercise guidelines are promoted for SCI individuals, when and how to incorporate exercise during the subacute phase post-SCI remains unclear. Consequently, early aerobic exercise to reduce CVD risks is not standard practice in subacute SCI care, potentially missing an opportunity for optimal cardiovascular rehabilitation, especially given observed reductions in cardiac structure and function within the first year post-SCI. Addressing this gap could improve long-term cardiovascular health and health-related quality of life (HRQOL) for individuals with SCI. Early intervention might prevent worsening cardiovascular function and establish beneficial exercise habits. However, few studies have evaluated the effectiveness of early exercise interventions in this population. This study aims to provide insight into the impact of moderate-intensity arm-crank exercise training (ACET) on cardiometabolic, HRQOL, functional and fitness parameters in individuals with subacute (<12 months postinjury) SCI.

METHODS AND ANALYSIS

We will conduct a single-centre, two-group, single-blind randomised controlled trial with 42 participants who have sustained a cervical or thoracic SCI within the past year. The non-intervention group will receive hospital standard of care (control group) while the intervention group will receive hospital standard of care plus moderate-intensity ACET for 10 weeks in line with the SCI-specific exercise guidelines to improve cardiometabolic health. The primary outcome measure will be central arterial stiffness (carotid-to-femoral pulse wave velocity). Secondary outcomes include assessments of (1) blood biomarkers linked to CVD, (2) cardiac structure and function, (3) extracranial vasculature, (4) HRQOL, (5) cognitive function, (6) physical activity level, (7) cardiorespiratory fitness, (8) motor function and (9) feasibility outcomes. Assessments will occur at baseline (rehabilitation centre admission, -2 weeks), preintervention (0 weeks), postintervention (10 weeks) and follow-up (6 months after postintervention), for HRQOL outcomes only.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Wales Research Ethics Committee (HREC 22/WA/0329). Outcome data will be presented at international conferences, patient advocacy groups, health professional networks and community health events. Findings will be published in peer-reviewed journals and widely disseminated through strategic channels to reach researchers, healthcare providers, patients and the public.

TRIAL REGISTRATION NUMBER

ISRCTN99941302.

The remapping of peripersonal space after stroke, spinal cord injury and amputation: A PRISMA systematic review

Peripersonal space (PPS) is the body-centered area where interactions occur and objects can be reached. Its boundaries are dynamic, modulated by ongoing sensorimotor experiences: limb immobilization shrinks PPS, whereas tool use expands it. However, consistent clinical information on PPS alterations remains limited due to methodological heterogeneity, varying types and severities of sensorimotor disorders, and diverse experimental paradigms. This review explores the causal mechanisms of PPS processing by integrating findings from brain-lesioned patients and individuals with body deafferentation, such as amputees and spinal cord injury (SCI) patients. By comparing the effects of brain lesions and sensorimotor deafferentation, it clarifies how PPS is encoded, maintained, and reorganized following central nervous system damage, bodily changes, and the use of assistive devices. A systematic search of Scopus, Web of Science, and PubMed identified 17 studies: 4 on stroke patients (N = 100), 6 on SCI patients (N = 104), and 7 on amputees (N = 65). Risk of bias was assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Despite the limited number of studies and methodological variability, findings consistently show that sensorimotor changes significantly affect PPS. Notably, a contraction of PPS around the affected limb was observed in stroke, SCI patients, and amputees. Assistive devices were able to restore PPS after training, or even immediately in the case of prosthesis use. A shared neurophysiological mechanism across these conditions may underlie PPS as an online construct, continuously updated to reflect the body's current state and its interaction with the environment.

Beyond the surface: understanding psychiatric disorders in individuals with spinal cord injury- a narrative exploration

PURPOSE

Spinal Cord Injury (SCI) presents a life-threatening condition that compromises the spinal cord's integrity. Among the complications affecting SCI patients are psychiatric disorders, whose causal mechanisms remain elusive. These disorders are often attributed to multifactorial aspects, encompassing physiological, neurobiological, psychological, and social factors. In the context of SCI patients, we are interested in identifying the specific factors that contribute to the development of psychiatric disorders in this population, emphasizing the critical need for prevention strategies and comprehensive therapeutic management, ultimately aiming to improve the affected patients' quality of life.

METHODS

The process of searching and selecting information was performed between August and December of 2023, utilizing PubMed, ResearchGate, and NCBI as the requisite databases for this review. To ensure precise information retrieval, keywords were strategically employed, focusing on publications spanning from 1985 to the present. MeSH terms, including spinal cord injury, acute spinal cord injury, psychiatric disorders, neuropsychiatry, cognitive impairment, and chronic pain, were applied. A total of 127 articles were identified through electronic searches, and 55 of these were chosen for inclusion in this review. The consulted studies encompassed various types, such as meta-analyses, systematic reviews, animal model experiments, and others.

RESULTS

Various factors contributing to the onset of psychiatric disorders in patients with SCI were proposed, all grounded in evidence: neurobiological pathology; cognitive impairment; the impact of systemic diseases on psychological well-being; and, lastly, the correlation between chronic pain and diminished daily functionality, experiences widely encountered by SCI patients.

CONCLUSION

The diagnosis of psychiatric disorders remains largely clinical and syndromic, with unclear causal mechanisms. Understanding psychiatric symptoms in SCI patients requires further investigation. Key contributing factors include neurobiological pathology linked to SCI, cognitive impairment, systemic and organ-specific diseases, and chronic pain associated with reduced functionality. We emphasize the importance of therapeutic and rehabilitative measures that address both physical and psychological health to improve overall quality of life.

The Role of Neuropsychology in the Management of Spinal Cord Injury: A Comprehensive Literature Review

Spinal cord injury (SCI) poses a complex set of physiological, psychological, and cognitive challenges that significantly affect an individual's quality of life. Analysis of longitudinal studies reveals that cognitive changes following SCI are often underestimated yet significantly impact patient's ability to adapt to their new circumstances. However, the role of neuropsychology in SCI management and rehabilitation is yet to be elucidated. This article offers an in-depth review of the role of neuropsychology in understanding and addressing the cognitive, emotional, and behavioral outcomes of SCI. Additionally, we delve into the emotional and psychological consequences of SCI, which can include increased stress, depression, anxiety, and potential changes in personality and social functioning. Neuropsychological assessment tools are highlighted as essential for diagnosing and monitoring these psychological shifts, aiding in the creation of personalized rehabilitation interventions. We also explore the role of neuroplasticity in cognitive rehabilitation post-SCI, emphasizing the potential of targeted cognitive training to alleviate cognitive deficits and improve adaptive functioning. The article further investigates the interplay between physical and cognitive recovery, underscoring the reciprocal relationship between motor function and cognitive improvement. In conclusion, this review emphasizes the crucial role of neuropsychology in understanding the multifaceted impact of SCI. By enhancing our comprehension of the intricate connections among neural integrity, cognitive function, and psychological well-being, neuropsychology provides valuable insights for developing holistic rehabilitation strategies that address both the cognitive and emotional challenges faced by individuals with SCI. As neurorehabilitation continues to advance, integrating neuropsychological principles offers promise for improving the overall recovery and quality of life for those affected by spinal cord injury.

Making the Invisible Visible: Understanding Autonomic Dysfunctions Following Spinal Cord Injury

Autonomic dysfunctions are a major challenge to individuals following spinal cord injury. Despite this, these consequences receive far less attention compared with motor recovery. This review will highlight the major autonomic dysfunctions following SCI predominantly based on our present understanding of the anatomy and physiology of autonomic control and available clinical data.

Exploring barriers to rehabilitation for individuals with spinal cord injury: a qualitative study in Iran

OBJECTIVES

Rehabilitation services are crucial for improving the quality of life and overall health of individuals with spinal cord injuries (SCIs). However, access to adequate rehabilitation remains limited in many regions, including Iran. This study aims to explore the barriers faced by individuals with SCIs in accessing appropriate rehabilitation services within Golestan province, northern of Iran.

METHODS

This study employed a qualitative approach to explore the barriers experienced by individuals with SCIs in accessing rehabilitation services. Fourteen participants were purposefully selected from the Golestan province (north of Iran) until data saturation was reached. Semi-structured interviews were conducted during the summer and fall of 2023, recorded, transcribed, and subjected to rigorous thematic analysis.

RESULTS

The study identified three primary categories of barriers: 1) Personal limiting factors, such as insufficient health literacy and inadequate home adaptations; 2) provider-related, including insufficient expertise, non-professional service delivery, inappropriate facility adaptations, limited service accessibility, and inadequate service provision; and 3) socio-supportive, encompassing companionship needs, financial constraints, insurance limitations, and bureaucratic hurdles.

CONCLUSION

The findings of this study highlight a complex interplay of patient, provider, and societal factors that impede access to rehabilitation services for individuals with spinal cord injuries in Golestan province. While provider-related challenges are prevalent, the significance of individual and socio-supportive factors cannot be overstated. To optimize rehabilitation outcomes, a holistic approach is essential, addressing not only physical impairments but also psychosocial and environmental barriers. The findings of this study underscore the complex interplay of patient, provider, and societal factors that influence access to rehabilitation services for individuals with spinal cord injuries. While provider-related challenges, such as insufficient expertise and limited service accessibility, are significant, the study emphasizes the crucial role of individual and socio-supportive factors in facilitating successful rehabilitation. Addressing these multifaceted barriers requires a holistic approach that considers not only physical impairments but also psychosocial and environmental needs.

The Effect of Non-Invasive, Non-Pharmacological Interventions on Autonomic Regulation of Cardiovascular Function in Adults with Spinal Cord Injury: A Systematic Review with Meta-Analysis

Autonomic regulation of cardiovascular function is often disrupted following a spinal cord injury (SCI). A systematic review was undertaken to evaluate the effect of non-invasive, non-pharmacological (NINP) interventions on cardiovascular autonomic biomarkers in adults with SCI. AMED, CENTRAL, CINAHL EMBASE, and MEDLINE were searched from inception to May 17, 2024. Randomized controlled trials (RCTs) of NINP interventions for cardiovascular autonomic biomarkers (heart rate variability [HRV], systolic blood pressure variability [SBPV], or baroreflex gain) in adults (≥18 years of age) with SCI (>3 months) were included. Primary outcomes included HRV (low-frequency power [HRV-LF], high-frequency power [HRV-HF], root mean square of successive differences [RMSSD]), SBPV (low-frequency power [SBPV-LF]), and baroreflex sensitivity. The quality and certainty of the evidence were assessed using version 2 of the Cochrane risk of bias tool and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis tool, respectively. Of 2651 records identified, six RCTs were included (participants, n = 123). HRV-LF (four studies; participants, n = 69) and HRV-HF (five studies; participants, n = 93) showed no to small changes in favor of NINP interventions ([g = 0.25; 95% confidence interval [CI] = -0.23, 0.73; p = 0.31; I2 = 0%], [g = 0.00; 95% CI = -0.41, 0.42; p = 0.98; I2 = 0%], respectively). Limited evidence was available for RMSSD, SBPV-LF, and baroreflex gain. This review found that the evidence is inconclusive regarding the effect of NINP interventions on the included HRV, BPV, and BRS parameters in adults with SCI. Further research with strong methodological rigor is needed to provide greater insights in this area.

Screening and outcomes of co-occurring traumatic brain injury among people with spinal cord injury: a scoping review

OBJECTIVE

To map existing knowledge on screening and rehabilitation outcomes for co-occurring traumatic brain injury among people with traumatic spinal cord injury (SCI).

METHODS

Articles focusing on screening and rehabilitation outcomes in participants sustaining co-occurring traumatic brain injury and traumatic spinal cord injury (all ages) were identified in Ovid, Scopus, Web of Science, CINAHL, and ProQuest Dissertations and Theses electronic databases. There were no limitations on study design, date, or geographical location. Articles were excluded if they were not available in English. Data were extracted into the Rayyan online collaboration platform and summarized descriptively.

RESULTS

Twenty-five studies were included, with a mix of retrospective, case-control, and prospective cohort designs. Screening under-estimated traumatic brain injury incidence when approaches relied on inconsistently collected traumatic brain injury indicators, especially for mild traumatic brain injury. Rehabilitation outcomes included length of stay, functional outcomes, cognitive functioning, complication rates, and employment. Although mixed, outcomes among persons with moderate to severe co-occurring traumatic brain injury especially, appeared poorer than those with spinal cord injury alone.

CONCLUSIONS

Multivariable approaches to traumatic brain injury ascertainment and greater consistency in documenting acute traumatic brain injury indicators may improve reliability of capturing traumatic brain injury and traumatic brain injury severity among persons with traumatic spinal cord injury. Impacts of co-occurring traumatic brain injury appear greater relative to SCI alone but few studies analysed outcomes based on traumatic brain injury severity.

Depression-like behavior is associated with deficits in cognition and hippocampal neurogenesis in a subset of spinally contused male, but not female, rats

Depression and cognitive deficits present at higher rates among people with spinal cord injury (SCI) compared to the general population, yet these SCI comorbidities are poorly addressed. Sex and age appear to play roles in depression incidence, but consensus on the direction of their effects is limited. Systemic and cortical inflammation and disruptions in hippocampal neurogenesis have been identified as potential treatment targets, but a comprehensive understanding of these mechanisms remains elusive. We used a rodent SCI model to interrogate these gaps in knowledge. We examined post-injury depression-like behavior and cognitive deficits, as well as the association between affect, cognition, chronic hippocampal inflammation and hippocampal neurogenesis, in young and middle-aged male and female Sprague-Dawley rats. Depression-like behavior manifested in male and female subsets of SCI rats irrespective of age, at rates commensurate with the incidence of clinical depression. Changes in components of behavior were driven by sex and age, and affective outcomes were independent of common post-injury pathophysiological outcomes including locomotor functional deficits and spinal lesion severity. Interestingly, however, only male depression-like SCI rats exhibited deficits in hippocampal-associated spatial cognition. Neurogenesis was also disrupted in only SCI males in regions of the hippocampus responsible for affective outcomes. Decreased neurogenesis among middle-aged male subjects coincided with increases in numbers of the pro-inflammatory markers CD86 and iNOS, while middle-aged females had increased numbers of cells expressing Iba-1 and anti-inflammatory marker CD206. Overall, the present data suggest that post-SCI depression and cognition may be affected, in part, by sex- and age-dependent changes in hippocampal neurogenesis and inflammation. Hippocampal neurogenesis is a potential target to address psychological wellbeing after SCI, but therapeutic strategies must carefully consider sex and age as biological variables.

Neurostimulation on lumbosacral nerves as a new treatment for spinal cord injury impairments and its impact on cortical activity: a narrative review

Spinal cord injury (SCI) can cause significant motor, sensory, and autonomic dysfunction by disrupting neural connections. As a result, it is a global health challenge that requires innovative interventions to improve outcomes. This review assesses the wide-ranging impacts of SCI and focuses on the laparoscopic implantation of neuroprosthesis (LION) as an emerging and promising rehabilitation technique. The LION technique involves the surgical implantation of electrodes on lumbosacral nerves to stimulate paralyzed muscles. Recent findings have demonstrated significant improvements in mobility, sexual function, and bladder/bowel control in chronic SCI patients following LION therapy. This manuscript revisits the potential physiological mechanisms underlying these results, including neuroplasticity and modulation of autonomic activity. Additionally, we discuss potential future applications and amendments of LION therapy. This study emphasizes the potential of neuromodulation as a complementary approach to traditional rehabilitation, that can provide a beacon of hope for improving functionality and quality of life for individuals with SCI.

Cognitive assessment during inpatient rehabilitation after spinal cord injury, a retrospective cross-sectional study

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

Cognitive screening is underdeveloped in spinal cord injury (SCI). Therefore, the objectives of our study were: (1) to evaluate cognitive functioning of rehabilitation inpatients with recently acquired spinal cord injury (SCI) with the Montreal Cognitive Assessment (MoCA); (2) to analyse associations between patient and lesion characteristics and the MoCA scores and (3) to compare the MoCA with the cognitive domain of the Utrecht scale for Evaluation of Rehabilitation (USER).

SETTING

Inpatient rehabilitation in a specialized rehabilitation centre in the Netherlands.

METHODS

MOCA and USER data of inpatients between November 2020 and December 2021 were used. Correlation and regression analysis were used.

RESULTS

Included were 98 adults aged (median) 61.6 years (range 19.5-83.6), 66% male, 26.5% traumatic SCI, 63% persons with paraplegia. MoCA and USER scores were available for 83 and 92 individuals, respectively. In 44.6% of the participants, the MoCA score was below the cut-off. Age (r = 0.31, p = 0.005) and educational level (r = 0.54 P < 0.00) were significantly correlated to the MoCA score. The MoCA and the cognitive domain of the USER were moderately correlated (r = 0.25, p = 0.03).

CONCLUSIONS

Almost half of the inpatients scored below the cut-off score on the MoCA. Since the MoCA is a validated cognitive screening tool, the moderate correlation of the MoCA and the cognitive domain of the USER suggests that the USER alone is not sufficient in detecting cognitive deficits. We recommend to screen for cognitive deficits in all people with new SCI.

SPONSORSHIP

None.

Efficacy of Blood Flow Restriction Exercise for Improving Lower Limb Muscle Strength and Function in Chronic Spinal Cord Injury: A Randomized Controlled Trial

The objective of the present study was to evaluate the efficacy of low-load (LL) blood flow restriction exercise (BFRE) for improving lower limb muscle strength, muscle thickness and physical function in individuals with spinal cord injury (SCI). In a randomized sham-controlled trial, 21 participants (age ≥ 18 years, SCI duration ≥ 1 year, knee extensor strength grade 2-4, ASIA A-D) were randomized to either 45-min LL-BFRE (n = 11) or sham BFRE (n = 10) twice/week for 8 weeks. The exercise protocol consisted of four sets (30 × 15 × 15 × 15 repetitions) of unilateral seated leg extensions and leg curls at 30%-40% of 1RM performed with pneumatic cuffs applied proximally on the trained limb and inflated to 40% of total arterial occlusion pressure (BFRE) or non-inflated (sham exercise). Maximal voluntary isometric quadriceps and hamstring muscle strength, quadriceps muscle thickness, thigh circumference, and physical function were assessed at baseline, after 4 and 8 weeks of training and at 4-week follow-up. No significant between-group differences were found between BFRE and sham exercise in quadriceps or hamstring muscle strength, 10-m walking test, timed up & go, 6-min walking test or the spinal cord independence measure. In contrast, a significant between-group difference favoring BFRE was present for muscle thickness and thigh circumference from baseline to 4-week follow-up (0.76 cm (95% CI: 0.32; 1.20, p = 0.002) and 2.42 cm (0.05; 4.79, p = 0.05), respectively). In conclusion, there was no significant difference in the effect of LL-BFRE and sham exercise on muscle strength and physical function in individuals with SCI. However, significant increases in muscle thickness and thigh circumference were observed in favor of BFRE. Trial Registration: ClinicalTrials.gov identifier: NCT03690700.

Complex lived experiences and hidden disability after spinal cord injury: a latent profile analysis of the Australian arm of the International Spinal Cord Injury (Aus-InSCI) Community Survey

PURPOSE

To identify and examine subgroups of people with spinal cord injury (SCI) with different patterns of lived experience, and examine hidden impairments and disability among functionally independent and ambulant people.

MATERIALS AND METHODS

Latent profile analysis of population-based data from the Australian arm of the International Spinal Cord Injury (InSCI) Community survey (n = 1579).

RESULTS

Latent subgroups reflected levels of functional independence and extent of problems with health, activity/participation, environmental barriers, and self-efficacy. Quality of life (QoL), psychological profiles, and activity/participation were often as good or better in participants who reported lower (vs. higher) functional independence alongside comparable burden of health problems and environmental barriers. QoL, mental health, and vitality reflected self-efficacy and problem burdens more closely than functional independence. Ambulant participants reported a substantial burden of underlying, potentially hidden impairments, with QoL and mental health similar to wheelchair users.

CONCLUSION

Hidden disability among more independent and/or ambulant people with SCI can affect well-being substantially. Early and ongoing access to support, rehabilitation, and SCI specialist services is important irrespective of cause, type, severity of injury, and level of functional independence. Improved access to SCI expertise and equity of care would help to improve early recognition and management of hidden disability.

TRIAL REGISTRATION

Not applicable.

A review of the sources and pharmacological research of morroniside

Introduction

Morroniside (Mor) is a bioactive compound found in Corni Fructus (CF) [Cornaceae; Cornus officinalis Siebold & Zucc.], which has been used as medicine and food in China, Korea, and Japan for over 2,000 years. This review summarizes recent progress on Mor, specifically focusing on its distribution, isolation, detection, and various pharmacological effects.

Methods

A literature survey on Mor was conducted using electronic databases such as PubMed, ScienceDirect, CNKI, and Google Scholar. After removing TCM prescription-related standards, medicinal herb processing-related research, and other irrelevant works of literature, we obtained relevant information on Mor's biological and pharmacological properties.

Results

The main conclusions are as follows: Mor is widely distributed in the plant kingdom; the methods for extracting and isolating Mor are well established; and the technology for detecting it is accurate. Mor exhibits numerous pharmacological effects. Along with CF, Mor has shown renoprotective effects against diabetes, hepatoprotective effects against diabetes, triptolide, and nonalcoholic steatohepatitis, and boneprotective effects against osteoporosis and osteoarthritis. In addition, researchers have also explored other pharmacological effects of Mor, including neuroprotective effects against focal cerebral ischemia, spinal cord injury, and Alzheimer's disease; cardioprotective effects against acute myocardial infarction; protection of the digestive system from gastritis, inflammatory bowel disease, and colitis; protection of the skin by promoting hair growth, wound healing, and flap survival; and protection of the lungs from acute lung injury and pulmonary fibrosis. Moreover, Mor has anti-obesity effects, anti-inflammatory effects in the eye, and improves follicular development.

Discussion

Overall, this review provides a comprehensive understanding of the pharmacological effects of Mor, from which the limitations of the current research can be understood, which will help facilitate future research.

Efficacy of Interventions to Improve Cognitive Function in Adults with Spinal Cord Injury: A Systematic Review

Cognitive impairment is a common complication following spinal cord injury (SCI) and imposes a significant negative impact on adjustment, functional independence, physical and mental health, and quality of life. It is unclear whether interventions for cognitive impairment following SCI are effective. A systematic review of controlled trials was performed to evaluate the effect of interventions on cognitive functions in adults with SCI using search engines: Embase, The Cochrane Library, MEDLINE, Scopus, CINAHL, and Web of Science up to December 2023. Two reviewers independently screened the articles, and study findings were synthesized and summarized. The risk of bias was evaluated using the Cochrane Risk of Bias 2.0 tool. Eight moderate-quality studies were found that investigated the effects of physical exercise/activity-based therapy plus cognitive training or intermittent hypoxia, diet modification and dietary supplements, tibial nerve or cortical stimulation, and drug therapy on cognitive function in SCI. Physical exercise/activity-based therapy plus cognitive training showed most promise for improving cognitive functions, while drug therapy, diet modification, and dietary supplements showed potential for improving cognitive function. However, about half of the participants experienced heightened instability in blood pressure following the administration of midodrine, and one participant reported gastrointestinal side effects after taking omega-3 fatty acids. There was no evidence of improvement in cognitive function for stimulation techniques. The current review highlights the scarcity of research investigating the effectiveness of interventions that target cognitive function after SCI. Further, the effects of these eight studies are uncertain due to concerns about the quality of designs and small sample sizes utilized in the trials, as well as the employment of insensitive neurocognitive tests when applied to adults with SCI. This review highlights a significant gap in knowledge related to SCI cognitive rehabilitation.

Spinal cord injury disrupts plasma extracellular vesicles cargoes leading to neuroinflammation in the brain and neurological dysfunction in aged male mice

Aged individuals with spinal cord injury (SCI) are prevalent with increased mortality and worse outcomes. SCI can cause secondary brain neuroinflammation and neurodegeneration. However, the mechanisms contributing to SCI-induced brain dysfunction are poorly understood. Cell-to-cell signaling through extracellular vesicles (EVs) has emerged as a critical mediator of neuroinflammation, including at a distance through circulation. We have previously shown that SCI in young adult (YA) male mice leads to robust changes in plasma EV count and microRNAs (miRs) content. Here, our goal was to investigate the impact of old age on EVs and brain after SCI. At 24 h post-injury, there was no difference in particle count or size distribution between YA and aged mice. However, aged animals increased expression of EV marker CD63 with SCI. Using the Fireplex® miRs assay, Proteomics, and mass spectrometry-based Lipidomics, circulating EVs analysis identified distinct profiles of miRs, proteins, and lipid components in old and injury animals. In vitro, plasma EVs from aged SCI mice, at a lower concentration comparable to those of YA SCI mice, induced the secretion of pro-inflammatory cytokines and neuronal apoptosis. Systemic administration of plasma EVs from SCI animals was sufficient to impair general physical function and neurological function in intact animals, which is associated with pro-inflammatory changes in the brain. Furthermore, plasma EVs from young animals had rejuvenating effects on naïve aged mice. Collectively, these studies identify the critical changes in circulating EVs cargoes after SCI and in aged animals and support a potential EV-mediated mechanism for SCI-induced brain changes.

Incident traumatic spinal cord injury and risk of Alzheimer's disease and related dementia: longitudinal case and control cohort study

STUDY DESIGN

Retrospective case/control longitudinal cohort study OBJECTIVES: Prevalent traumatic spinal cord injury (TSCI) is associated with Alzheimer's disease and related dementia (ADRD). We examined the hazard ratio for ADRD after incident TSCI and hypothesized that ADRD hazard is greater among adults with incident TSCI compared with their matched control of adults without TSCI.

SETTING

Using 2010-2020 U.S. national private administrative claims data, we identified adults aged 45 years and older with probable (likely and highly likely) incident TSCI (n = 657). Our controls included one-to-ten matched cohort of people without TSCI (n = 6553).

METHODS

We applied Cox survival models and adjusted them for age, sex, years of living with certain chronic conditions, exposure to six classes of prescribed medications, and neighborhood characteristics of place of residence. Hazard ratios were used to compare the results within a 4-year follow-up.

RESULTS

Our fully adjusted model without any interaction showed that incident TSCI increased the risk for ADRD (HR = 1.30; 95% CI, 1.01-1.67). People aged 45-64 with incident TSCI were at high risk for ADRD (HR = 5.14; 95% CI, 2.27-11.67) and no significant risk after age 65 (HR = 1.20; 95% CI, .92-1.55). Our sensitivity analyses confirmed a higher hazard ratio for ADRD after incident TSCI at 45-64 years of age compared with the matched controls.

CONCLUSIONS

TSCI is associated with a higher hazard of ADRD. This study informs the need to update clinical guidelines for cognitive screening after TSCI to address the heightened risk of cognitive decline and to shed light on the causality between TSCI and ADRD.

Old age alters inflammation and autophagy signaling in the brain, leading to exacerbated neurological outcomes after spinal cord injury in male mice

Older patients with spinal cord injury (SCI) have different features with regard to neurological characteristics after injury. Recent large-scale longitudinal population-based studies showed that individuals with SCI are at a higher risk of developing dementia than non-SCI patients, indicating that SCI is a potential risk factor for dementia. Aging is known to potentiate inflammation and neurodegeneration at the injured site leading to impaired recovery from SCI. However, no research has been aimed at studying the mechanisms of SCI-mediated cognitive impairment in the elderly. The present study examined neurobehavioral and molecular changes in the brain and the underlying mechanisms associated with brain dysfunction in aged C57BL/6 male mice using a contusion SCI model. At 2 months post-injury, aged mice displayed worse performance in locomotor, cognitive and depressive-like behavioral tests compared to young adult animals. Histopathology in injured spinal cord tissue was exacerbated in aged SCI mice. In the brain, transcriptomic analysis with NanoString neuropathology panel identified activated microglia and dysregulated autophagy as the most significantly altered pathways by both age and injury. These findings were further validated by flow cytometry, which demonstrated increased myeloid and lymphocytes infiltration at both the injured site and brain of aged mice. Moreover, SCI in aged mice altered microglial function and dysregulated autophagy in microglia, resulting in worsened neurodegeneration. Taken together, our data indicate that old age exacerbates neuropathological changes in both the injured spinal cord and remote brain regions leading to poorer functional outcomes, at least in part, through altered inflammation and autophagy function.

Chronic opioid prescription in veterans with spinal cord injury: Prevalence and associated factors

OBJECTIVE

Chronic opioid use presents long-term health risks for individuals with spinal cord injury (SCI). The purpose of the study was to characterize patterns and correlates of the chronic prescription of opioids among individuals with SCI in a population of Veterans receiving care though the Veteran's Health Administration.

DESIGN

A retrospective, longitudinal cohort study examined the US Department of Veterans Affairs electronic medical record data of veterans with SCI. The annual prevalence of prescription opioid use by type (any, acute, chronic, incident chronic) was calculated for each study year (2015-2017). Multivariable models examined associations with demographics and pre-existing medical comorbidities.

SETTING

US Department of Veterans Affairs, Veteran's Health Administration.

PARTICIPANTS

National sample of Veterans with SCI (N = 10,811).

MAIN OUTCOME MEASURE

Chronic prescription opioid use (≥90 days).

RESULTS

All types of prescription opioid use declined across the three study years (chronic opioid use prevalence = 33.2%, 31.7%, and 29.7%, respectively). Past history of depression, COPD, diabetes, pain condition, opioid use and tobacco use disorders were associated with a greater likelihood of current chronic prescription opioid use. Non-white race, hyperlipidemia, dementia, and tetraplegia were associated with a lower likelihood of current chronic prescription opioid use. When added to the multivariable model, prior chronic opioid prescription use was robustly associated with current chronic prescription opioid use, but most other factors were no longer significantly associated with current opioid use.

CONCLUSIONS

This study demonstrates opioid reduction over time from 2015 to 2017, however, chronic prescription opioid use remains common among a substantial minority of Veterans with SCI. Several demographics and comorbidities may provide clinicians with important insights into factors associated with chronic prescription opioid use, with past chronic prescription opioid use being the most important.

Delayed cerebrovascular reactivity in individuals with spinal cord injury in the right inferior parietal lobe: a breath-hold functional near-infrared spectroscopy study

Cerebrovascular reactivity (CVR) reflects the ability of blood vessels to dilate or constrict in response to a vasoactive stimulus, and allows researchers to assess the brain's vascular health. Individuals with spinal cord injury (SCI) are at an increased risk for autonomic dysfunction in addition to cognitive impairments, which have been linked to a decline in CVR; however, there is currently a lack of brain-imaging studies that investigate how CVR is altered after SCI. In this study, we used a breath-holding hypercapnic stimulus and functional near-infrared spectroscopy (fNIRS) to investigate CVR alterations in individuals with SCI (n = 20, 14M, 6F, mean age = 46.3 ± 10.2 years) as compared to age- and sex-matched able-bodied (AB) controls (n = 25, 19M, 6F, mean age = 43.2 ± 12.28 years). CVR was evaluated by its amplitude and delay components separately by using principal component analysis and cross-correlation analysis, respectively. We observed significantly delayed CVR in the right inferior parietal lobe in individuals with SCI compared to AB controls (linear mixed-effects model, fixed-effects estimate = 6.565, Satterthwaite's t-test, t = 2.663, p = 0.008), while the amplitude of CVR was not significantly different. The average CVR delay in the SCI group in the right inferior parietal lobe was 14.21 s (sd: 6.60 s), and for the AB group, the average delay in the right inferior parietal lobe was 7.08 s (sd: 7.39 s). CVR delays were also associated with the duration since injury in individuals with SCI, in which a longer duration since injury was associated with a shortened delay in CVR in the right inferior parietal region (Pearson's r-correlation, r = -0.59, p = 0.04). This study shows that fNIRS can be used to quantify changes in CVR in individuals with SCI, and may be further used in rehabilitative settings to monitor the cerebrovascular health of individuals with SCI.

Analysis of Influencing Factors of Major Depression After Spinal Cord Injury

Objective

To analyze the risk factors of major depressive disorder (MDD) after spinal cord injury (SCI).

Methods

Patients with SCI in our hospital from February 2020 to February 2023 were selected as the study objects. According to the Hamilton Depression Scale (HAMD) score, patients with 36~75 points were included in the major depression group, and 0~35 points were included in the non-major depression group. The general sociological characteristics (age, gender, educational level, place of residence, family economic status, payment method of medical expenses, marital status) and disease-related characteristics (course of disease, cause of injury, neurological level of injury, type of injury, degree of pain) of all patients were collected, and the items with differences were selected for logistic regression analysis to analyze the risk factors for major depression in patients with spinal cord injury.

Results

Totally 216 patients were enrolled in our study, including 45 patients (18.98%) had moderate-to-severe depression and 175 patients (81.02%) had non-severe depression. Univariate analysis showed that gender (χ2 = 11.865, P < .001), course of disease (χ2 = 12.967, P < .001), family economic status (χ2 = 8.610, P = .003), educational level (χ2 =15.287, P < .001), neurological level of injury (χ2 = 9.013, P = .003) and pain level (χ2 = 16.673, P < .001) were statistically significant differences between the 2 groups. Multivariate logistic regression analysis showed that gender [odds ratio (OR) (95 % CI) = 3.986 (1.743~9.116), P = .001], course of disease [OR (95 % CI) = 4.033 (1.818~8.947), P = .001], family economic status [OR (95 % CI) = 3.136 (1.449~6.785), P = .004], educational level [OR (95 % CI) = 4.332 (1.998~9.388), P = .000], neurological level of injury [OR (95 % CI) = 2.848 (1.414~5.734), P = .003], and pain level [OR (95 % CI) = 5.767 (2.309~14.404), P < .001] were risk factors for major depressive disorder in SCI patients.

Conclusion

Gender, disease duration, family economic status, education level, level of nerve injury, and pain level may be the independent risk factors of MDD incidence in patients with spinal cord injury.

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.

Cerebrovascular Reactivity Following Spinal Cord Injury

Background

Spinal cord injuries (SCI) often result in cardiovascular issues, increasing the risk of stroke and cognitive deficits.

Objectives

This study assessed cerebrovascular reactivity (CVR) using functional magnetic resonance imaging (fMRI) during a hypercapnic challenge in SCI participants compared to noninjured controls.

Methods

Fourteen participants were analyzed (n = 8 with SCI [unless otherwise noted], median age = 44 years; n = 6 controls, median age = 33 years). CVR was calculated through fMRI signal changes.

Results

The results showed a longer CVR component (tau) in the grey matter of SCI participants (n = 7) compared to controls (median difference = 3.0 s; p < .05). Time since injury (TSI) correlated negatively with steady-state CVR in the grey matter and brainstem of SCI participants (RS = -0.81, p = .014; RS = -0.84, p = .009, respectively). Lower steady-state CVR in the brainstem of the SCI group (n = 7) correlated with lower diastolic blood pressure (RS = 0.76, p = .046). Higher frequency of hypotensive episodes (n = 7) was linked to lower CVR outcomes in the grey matter (RS = -0.86, p = .014) and brainstem (RS = -0.89, p = .007).

Conclusion

Preliminary findings suggest a difference in the dynamic CVR component, tau, between the SCI and noninjured control groups, potentially explaining the higher cerebrovascular health burden in SCI individuals. Exploratory associations indicate that longer TSI, lower diastolic blood pressure, and more hypotensive episodes may lead to poorer CVR outcomes. However, further research is necessary to establish causality and support these observations.

Metacognitive accuracy predicts self-reported quality of life following traumatic brain injury

OBJECTIVE

Metacognition and quality of life (QoL) are both adversely affected by traumatic brain injury (TBI), but the relation between them is not fully understood. As such, the purpose of this study was to determine the degree to which metacognitive accuracy predicts QoL in individuals with TBI.

METHODS

Eighteen participants with moderate-to-severe TBI completed a stimulus-response task requiring the discrimination of emotions depicted in pictures of faces and then provided a retrospective confidence judgment after each response. Metacognitive accuracy was calculated using participants' response accuracy and confidence judgment accuracy. Participants also completed the Quality of Life After Brain Injury (QOLIBRI) questionnaire to assess QoL in various areas of functioning.

RESULTS

Performance of a linear regression analysis revealed that higher metacognitive accuracy significantly predicted lower overall QoL. Additionally, higher metacognitive accuracy significantly predicted lower QoL related to cognition and physical limitations.

CONCLUSION

The study results provide evidence of an inverse relation between metacognitive performance and QoL following TBI. Metacognitive changes associated with TBI and their relation to QoL have several clinical implications for TBI rehabilitation.

Longitudinal motor system changes from acute to chronic spinal cord injury

BACKGROUND AND PURPOSE

In acute spinal cord injury (SCI), magnetic resonance imaging (MRI) reveals tissue bridges and neurodegeneration for 2 years. This 5-year study aims to track initial lesion changes, subsequent neurodegeneration, and their impact on recovery.

METHODS

This prospective longitudinal study enrolled acute SCI patients and healthy controls who were assessed clinically-and by MRI-regularly from 3 days postinjury up to 60 months. We employed histologically cross-validated quantitative MRI sequences sensitive to volume, myelin, and iron changes, thereby reflecting indirectly processes of neurodegeneration and neuroinflammation. General linear models tracked lesion and remote changes in volume, myelin- and iron-sensitive magnetic resonance indices over 5 years. Associations between lesion, degeneration, and recovery (using the Spinal Cord Independence Measure [SCIM] questionnaire and the International Standards for Neurological Classification of Spinal Cord Injury total motor score) were assessed.

RESULTS

Patients' motor scores improved by an average of 12.86 (95% confidence interval [CI] = 6.70-19.00) points, and SCIM by 26.08 (95% CI = 17.00-35.20) points. Within 3-28 days post-SCI, lesion size decreased by more than two-thirds (3 days: 302.52 ± 185.80 mm2 , 28 days: 76.77 ± 88.62 mm2 ), revealing tissue bridges. Cervical cord and corticospinal tract volumes transiently increased in SCI patients by 5% and 3%, respectively, accompanied by cervical myelin decreases and iron increases. Over time, progressive atrophy was observed in both regions, which was linked to early lesion dynamics. Tissue bridges, reduced swelling, and myelin content decreases were predictive of long-term motor score recovery and improved SCIM score.

CONCLUSIONS

Studying acute changes and their impact on longer follow-up provides insights into SCI trajectory, highlighting the importance of acute intervention while indicating the potential to influence outcomes in the later stages.

Cognitive, behavioral and psychiatric symptoms in patients with spinal cord injury: a scoping review

Spinal Cord Injury (SCI) is a condition where the spinal cord is damaged and experiences partial or complete loss of motor and/or sensory function, which is typically less than normal. After SCI, patients may exhibit more severe psychiatric symptoms and experience cognitive impairments, including reduced speed and attention processing capacity, as well as difficulties with executive function and episodic memory retention. Among the behavioral and psychiatric symptoms, depression, anxiety, substance use disorder, and posttraumatic stress disorder are the most common. This review aims to investigate the cognitive, behavioral, or psychiatric symptoms of the patient with SCI and their influence on the rehabilitation process. Studies were identified from an online search of PubMed, Web of Science, Cochrane Library, and Embase databases. Studies published between 2013-2023 were selected. This review has been registered on OSF (n) 3KB2U. We have found that patients with SCI are at high risk of cognitive impairment and experience a wide range of difficulties, including tasks based on processing speed and executive function. This clinical population may experience adjustment disorders with depression and anxiety, as well as other psychiatric symptoms such as fatigue, stress, and suicidal ideation. This review has demonstrated that SCI patients may experience psychiatric symptoms and cognitive impairments that affect their functioning. At the same time, these patients may be more prone to various adjustment and mood disorders. Moreover, these two aspects may interact with each other, causing a range of symptoms, increasing the risk of hospitalization, and delaying the rehabilitation process.

Explaining the challenges of Iranian caregivers in provision of home health care to spinal cord injury patients: a qualitative study

BACKGROUND

The incidence of spinal cord injury (SCI) is increasing across the globe. The caregivers of patients with spinal cord injuries experience many problems during providing care to these patients. Identifying the problems experienced by caregivers can facilitate the process of care provision to these patients. So, the aim of this study was to explore the challenges of caregivers in provision of home health care to SCI patients.

METHODS

This study was conducted by qualitative description approach in Iran from Apr 2021 to Dec 2022. The participants included the caregivers of SCI patients recruited by purposive sampling. The data were collected by face-to-face interviews and analyzed using the method proposed by Lundman and Graneheim.

RESULTS

Two themes emerged from the data analysis, including burnout (with the categories of physical challenge and psychological challenges) and coping strategies (with the categories of social support and professional support).

CONCLUSION

Resolving the obstacles and problems faced by home caregivers can improve the circumstances of care provision so that they can be relieved of their own physical and psychological conundrums and deliver suitable home care to SCI patients.

TRIAL REGISTRATION NUMBER

Not applicable.

Brain activation during the N-back working memory task in individuals with spinal cord injury: a functional near-infrared spectroscopy study

Cognitive impairments have frequently been reported in individuals with spinal cord injury (SCI) across different domains such as working memory, attention, and executive function. The mechanism of cognitive impairment after SCI is not well understood due to the heterogeneity of SCI sample populations, and may possibly be due to factors such as cardiovascular dysfunction, concomitant traumatic brain injury (TBI), hypoxia, sleep disorders, and body temperature dysregulation. In this study, we implement the Neuropsychiatric Unit Cognitive Assessment Tool (NUCOG) to assess cognitive differences between individuals with SCI and age-matched able-bodied (AB) controls. We then use an N-back working memory task and functional near-infrared spectroscopy (fNIRS) to elucidate the neurovascular correlates of cognitive function in individuals with SCI. We observed significant differences between the SCI and AB groups on measures of executive function on the NUCOG test. On the N-back task, across the three levels of difficulty: 0-back, 2-back, and 3-back, no significant differences were observed between the SCI and AB group; however, both groups performed worse as the level of difficulty increased. Although there were no significant differences in N-back performance scores between the two groups, functional brain hemodynamic activity differences were observed between the SCI and AB groups, with the SCI group exhibiting higher maximum oxygenated hemoglobin concentration in the right inferior parietal lobe. These findings support the use of fNIRS to study cognitive function in individuals with SCI and may provide a useful tool during rehabilitation to obtain quantitative functional brain activity metrics.

Improving Outcomes in People with Spinal Cord Injury: Encouraging Results from a Multidisciplinary Advanced Rehabilitation Pathway

Spinal cord injury (SCI) consists of damage to any segment of the spinal cord extending to potential harm to nerves in the cauda equina. Rehabilitative efforts for SCI can involve conventional physiotherapy, innovative technologies, as well as cognitive treatment and psychological support. The aim of this study is to evaluate the feasibility of a dedicated, multidisciplinary, and integrated intervention path for SCI, encompassing both conventional and technological interventions, while observing their impact on cognitive, motor, and behavioral outcomes and the overall quality of life for individuals with SCI. Forty-two patients with SCI were included in the analysis utilizing electronic recovery system data. The treatment regimen included multidisciplinary rehabilitation approaches, such as traditional physiotherapy sessions, speech therapy, psychological support, robotic devices, advanced cognitive rehabilitation, and other interventions. Pre-post comparisons showed a significant improvement in lower limb function (Fugl Meyer Assessment-FMA < 0.001), global cognitive functioning (Montreal Cognitive Assessment-MoCA p < 0.001), and perceived quality of life at both a physical and mental level (Short Form-12-SF-12 p < 0.001). Furthermore, we found a significant reduction in depressive state (Beck Depression Inventory-BDI p < 0.001). In addition, we assessed patient satisfaction using the Short Form of the Patient Satisfaction Questionnaire (PSQ), offering insights into the subjective evaluation of the intervention. In conclusion, this retrospective study provides positive results in terms of improvements in motor function, cognitive functions, and quality of life, highlighting the importance of exploring multidisciplinary approaches.

Brain MRI changes in degenerative cervical myelopathy: a systematic review

BACKGROUND

Degenerative cervical myelopathy (DCM) is the most common cause of adult spinal cord dysfunction globally. Associated neurological symptoms and signs have historically been explained by pathobiology within the cervical spine. However, recent advances in imaging have shed light on numerous brain changes in patients with DCM, and it is hypothesised that these changes contribute to DCM pathogenesis. The aetiology, significance, and distribution of these supraspinal changes is currently unknown. The objective was therefore to synthesise all current evidence on brain changes in DCM.

METHODS

A systematic review was performed. Cross-sectional and longitudinal studies with magnetic resonance imaging on a cohort of patients with DCM were eligible. PRISMA guidelines were followed. MEDLINE and Embase were searched to 28th August 2023. Duplicate title/abstract screening, data extraction and risk of bias assessments were conducted. A qualitative synthesis of the literature is presented as per the Synthesis Without Meta-Analysis (SWiM) reporting guideline. The review was registered with PROSPERO (ID: CRD42022298538).

FINDINGS

Of the 2014 studies that were screened, 47 studies were identified that used MRI to investigate brain changes in DCM. In total, 1500 patients with DCM were included in the synthesis, with a mean age of 53 years. Brain alterations on MRI were associated with DCM both before and after surgery, particularly within the sensorimotor network, visual network, default mode network, thalamus and cerebellum. Associations were commonly reported between brain MRI alterations and clinical measures, particularly the Japanese orthopaedic association (JOA) score. Risk of bias of included studies was low to moderate.

INTERPRETATION

The rapidly expanding literature provides mounting evidence for brain changes in DCM. We have identified key structures and pathways that are altered, although there remains uncertainty regarding the directionality and clinical significance of these changes. Future studies with greater sample sizes, more detailed phenotyping and longer follow-up are now needed.

FUNDING

ODM is supported by an Academic Clinical Fellowship at the University of Cambridge. BMD is supported by an NIHR Clinical Doctoral Fellowship at the University of Cambridge (NIHR300696). VFJN is supported by an NIHR Rosetrees Trust Advanced Fellowship (NIHR302544). This project was supported by an award from the Rosetrees Foundation with the Storygate Trust (A2844).

The Clinical Relevance of Autonomic Dysfunction, Cerebral Hemodynamics, and Sleep Interactions in Individuals Living With SCI

A myriad of physiological impairments is seen in individuals after a spinal cord injury (SCI). These include altered autonomic function, cerebral hemodynamics, and sleep. These physiological systems are interconnected and likely insidiously interact leading to secondary complications. These impairments negatively influence quality of life. A comprehensive review of these systems, and their interplay, may improve clinical treatment and the rehabilitation plan of individuals living with SCI. Thus, these physiological measures should receive more clinical consideration. This special communication introduces the under investigated autonomic dysfunction, cerebral hemodynamics, and sleep disorders in people with SCI to stakeholders involved in SCI rehabilitation. We also discuss the linkage between autonomic dysfunction, cerebral hemodynamics, and sleep disorders and some secondary outcomes are discussed. Recent evidence is synthesized to make clinical recommendations on the assessment and potential management of important autonomic, cerebral hemodynamics, and sleep-related dysfunction in people with SCI. Finally, a few recommendations for clinicians and researchers are provided.

Activation of SIRT1 by hyperbaric oxygenation promotes recovery of motor dysfunction in spinal cord injury rats

BACKGROUND

Hyperbaric oxygenation (HBO) therapy can improve locomotor dysfunction following spinal cord injury (SCI). Emerging evidence has demonstrated that sirtuin1 (SIRT1) exerts protective effects on neurons. However, whether HBO alleviates locomotor dysfunction by regulating SIRT1 is unclear.

METHODS

The traumatic SCI animal model was performed on the adult Sprague-Dawley rats. The Basso, Beattie Bresnahan (BBB) locomotor rating scale was used to evaluate the open-field locomotor function. Western blot, real-time quantitative reverse transcription polymerase chain reaction, SIRT1 activity assay, and enzyme-linked immunosorbent assays were performed to explore the molecular mechanisms.

RESULTS

We found that series HBO therapy significantly improved locomotor dysfunction and ameliorated the decreased mRNA, protein, and activity of spinal cord SIRT1 induced by traumatic SCI injury in rats. In addition, intraperitoneal injection of SIRT1 inhibitor EX-527 abolished the beneficial effects of series HBO treatment on locomotor deficits. Importantly, series HBO treatment following the traumatic SCI injury inhibited the inflammatory cascade and apoptosis-related protein, which was retained by EX-527 and enhanced by SRT1720. Furthermore, EX-527 blocked the enhanced induction of autophagy series with the HBO application.

CONCLUSION

These findings demonstrated a new mechanism for series HBO therapy involving activation of SIRT1 and subsequent modulation of the inflammatory cascade, apoptosis, and autophagy, which contributed to the recovery of motor dysfunction.

Cognitive Failure in Adults with Spinal Cord Injury: A Valuable Adjunct Measure for Enhancing Cognitive Assessment and Rehabilitation Outcomes

Cognitive impairment is common in persons with spinal cord injury (SCI), impacting their daily functioning and rehabilitation. This study assesses the extent of self-reported cognitive failures in everyday life in persons with SCI and its relationships with objective neurocognitive measures and psychosocial factors, including depressive mood, anxiety, perceived control, and fatigue. The differences between forty-one adults with a chronic SCI and forty-one able-bodied controls were examined. The participants completed the Cognitive Failures Questionnaire (CFQ) to assess cognitive failure and neurocognitive tests assessing attention and executive functions, as well as a psychosocial assessment. The SCI group reported higher cognitive failure rates than the able-bodied group (31.7% versus 19%, p > 0.05). Objective neurocognitive tests did not significantly correlate with the CFQ scores in either group. However, the CFQ scores were positively associated with most psychosocial factors, even after controlling for covariates. The CFQ scores were significantly associated with depressive mood in persons with SCI. These findings highlight the importance of incorporating self-reported cognitive measures into neurocognitive assessments and rehabilitation planning for adults with SCI. Self-reports capture everyday cognitive challenges that objective tests may miss. Additionally, this study highlights the strong connections between cognitive failures and psychosocial issues, particularly mood disorders, emphasizing the need for comprehensive rehabilitation and psychosocial support post-SCI, addressing both cognitive and emotional wellbeing.

Pulse rate variability: An alternative to heart rate variability in adults with spinal cord injury

Pulse rate variability (PRV) is often used as an alternative to heart rate variability (HRV) to measure psychophysiological function. However, its validity to do so is unclear, especially in adults with spinal cord injury (SCI). This study compared PRV and HRV in adults with higher-level SCI (SCI-H, n = 23), lower-level SCI (SCI-L, n = 22), and able-bodied participants (AB n = 44), in a seated position as a function of performance in a reactivity task (Oxford Sleep Resistance Test: OSLER). PRV and HRV was measured using reflective finger-based photoplethysmography (PPG) and electrocardiography, respectively, at baseline, immediately post-OSLER, and after five-minute recovery. Agreement between PRV and HRV was determined by Bland-Altman analysis and differences between PRV and HRV over time by linear mixed effects model (LMM) analysis. Concurrent validity was assessed through correlation analyses between PRV and HRV. Additional correlation analyses were performed with psychosocial factors. Results indicated insufficient to moderate agreement between PRV and HRV. LMM analyses indicated no differences over time for standard deviation of normal-to-normal intervals and low-frequency power but significant differences for root mean square of successive differences and high frequency power. Nevertheless, PRV and HRV were highly correlated (Median r = .878 (.675-.990)) during all assessment periods suggesting sufficient concurrent validity. Similar correlation patterns were also found for PRV and HRV with psychosocial outcomes. While differences existed, results suggest PRV derived from reflective finger-based PPG is a valid proxy of HRV in tracking psychophysiological function in adults with SCI and could therefore be used as a more accessible monitoring tool.

Massive body-brain disconnection consequent to spinal cord injuries drives profound changes in higher-order cognitive and emotional functions: A PRISMA scoping review

Spinal cord injury (SCI) leads to a massive disconnection between the brain and the body parts below the lesion level representing a unique opportunity to explore how the body influences a person's mental life. We performed a systematic scoping review of 59 studies on higher-order cognitive and emotional changes after SCI. The results suggest that fluid abilities (e.g. attention, executive functions) and emotional regulation (e.g. emotional reactivity and discrimination) are impaired in people with SCI, with progressive deterioration over time. Although not systematically explored, the factors that are directly (e.g. the severity and level of the lesion) and indirectly associated (e.g. blood pressure, sleeping disorders, medication) with the damage may play a role in these deficits. The inconsistency which was found in the results may derive from the various methods used and the heterogeneity of samples (i.e. the lesion completeness, the time interval since lesion onset). Future studies which are specifically controlled for methods, clinical and socio-cultural dimensions are needed to better understand the role of the body in cognition.

The gray matter atrophy and related network changes occur in the higher cognitive region rather than the primary sensorimotor cortex after spinal cord injury

Objective

This study used functional magnetic resonance imaging (fMRI) to explore brain structural and related network changes in patients with spinal cord injury (SCI).

Methods

Thirty-one right-handed SCI patients and 31 gender- and age-matched healthy controls (HC) were included. The gray matter volume (GMV) changes in SCI patients were observed using voxel-based morphometry (VBM). Then, these altered gray matter clusters were used as the regions of interest (ROIs) for whole-brain functional connectivity (FC) analysis to detect related functional changes. The potential association between GMV and FC values with the visual analog scale (VAS), the American Spinal Injury Association (ASIA) score, and the course of injuries was investigated through partial correlation analysis.

Results

GMV of the frontal, temporal, and insular cortices was lower in the SCI group than in the HC group. No GMV changes were found in the primary sensorimotor area in the SCI group. Besides, the altered FC regions were not in the primary sensorimotor area but in the cingulate gyrus, supplementary motor area, precuneus, frontal lobe, and insular. Additionally, some of these altered GMV and FC regions were correlated with ASIA motor scores, indicating that higher cognitive regions can affect motor function in SCI patients.

Conclusions

This study demonstrated that gray matter and related network reorganization in patients with SCI occurred in higher cognitive regions. Future rehabilitation strategies should focus more on cognitive functions.

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.

Magnetic resonance spectroscopy investigation in the right human hippocampus following spinal cord injury

Objective

Preclinical studies have shown that cognitive impairments following spinal cord injury (SCI), such as impaired spatial memory, are linked to inflammation, neurodegeneration, and reduced neurogenesis in the right hippocampus. This cross-sectional study aims to characterize metabolic and macrostructural changes in the right hippocampus and their association to cognitive function in traumatic SCI patients.

Methods

Within this cross-sectional study, cognitive function was assessed in 28 chronic traumatic SCI patients and 18 age-, sex-, and education-matched healthy controls by a visuospatial and verbal memory test. A magnetic resonance spectroscopy (MRS) and structural MRI protocol was performed in the right hippocampus of both groups to quantify metabolic concentrations and hippocampal volume, respectively. Group comparisons investigated changes between SCI patients and healthy controls and correlation analyses investigated their relationship to memory performance.

Results

Memory performance was similar in SCI patients and healthy controls. The quality of the recorded MR spectra was excellent in comparison to the best-practice reports for the hippocampus. Metabolite concentrations and volume of the hippocampus measured based on MRS and MRI were not different between two groups. Memory performance in SCI patients and healthy controls was not correlated with metabolic or structural measures.

Conclusion

This study suggests that the hippocampus may not be pathologically affected at a functional, metabolic, and macrostructural level in chronic SCI. This points toward the absence of significant and clinically relevant trauma-induced neurodegeneration in the hippocampus.

Exploring caregivers' perceptions of community-based service requirements of patients with spinal cord injury: a qualitative study

BACKGROUND

The incidence of spinal cord injury is increasing worldwide. Patients with spinal cord injury and their families face many difficulties during the disease course. Caregivers are more involved with these patients than anyone else, so recognizing patients' care requirements based on caregivers' opinions can facilitate care provision to these people. The purpose of this study was to explore caregivers' perceptions of the community-based services requirements of patients with spinal cord injury.

METHODS

This qualitative research was conducted in Iran from Apr 2021 to Dec 2022 using the conventional content analysis method. The participants in the study included family caregivers and providers of home care services to patients with spinal cord injury, who were selected by purposeful sampling. Data were collected by conducting 14 face-to-face interviews and analyzed based on the method proposed by Lundman and Graneheim.

RESULTS

Data analysis led to the extraction of 815 primary codes, which were organized into two themes: community reintegration (with two categories, including the need to provide a suitable social platform and lifelong care) and palliative care (with two categories, including family conference and survival management).

CONCLUSION

Social facilities and infrastructure should be modified in a way that patients with spinal cord injury can appropriately benefit from community-based care services and an independent satisfactory life. Palliative care should be continuously provided from the time of lesion development until the patient's death.

Cannabis health survey on usage in women with spinal cord injury and knowledge among physicians: A cross-sectional study

OBJECTIVE

Individuals with spinal cord injury (SCI) report using cannabis to self-manage chronic pain and spasticity. However, its safety and efficacy are not well understood. As more women with SCI are pursuing motherhood, clinicians must consider the possibility of maternal cannabis use and its impact on fetal development. Moreover, due to the lack of current evidence for cannabis, it is important to characterize the perceptions and knowledge of physicians towards both recreational and synthetic cannabinoids.

DESIGN

Two anonymous surveys (10-items each) were conducted.

SETTING AND PARTICIPANTS

Women with SCI (n = 20) completed an anonymous, online survey regarding cannabis use. Physicians at a Canadian SCI rehabilitation center (n = 15) completed a survey on their knowledge of recreational and synthetic cannabinoids among individuals with SCI.

OUTCOME MEASURES

Survey 1 evaluated cannabis use patterns and perceptions before/after SCI in women, including during pregnancy and breastfeeding. The aim of Survey 2 was to understand the perception and current knowledge of physicians regarding recreational cannabis and synthetic cannabinoid use by patients with SCI.

RESULTS

At the time of survey, 7 women with SCI reported use of cannabis, only 4 of them used prior to injury. Managing tone/spasticity (n = 5) was the major reported benefit of cannabis use. Women used cannabis during pregnancy and/or breastfeeding as a sleep aid or relief for morning sickness (n = 1 pregnancy, n = 1 breastfeeding, n = 1 both). The most-reported challenge with cannabis use was difficulty obtaining consistent, desirable effects (n = 5). Almost all physicians (n = 13) described their knowledge on recreational cannabis products as "none, very little or poor", with greater overall comfort and knowledge of synthetic cannabinoids.

CONCLUSION

Due to the reported use of cannabis during pregnancy/breastfeeding and current impoverishment of physicians' knowledge (particularly regarding recreational cannabis products), it is imperative to further investigate the safety and efficacy of cannabis use in women with SCI.

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.

Hydralazine plays an immunomodulation role of pro-regeneration in a mouse model of spinal cord injury

Spinal cord injury (SCI) results in severe motor and sensory dysfunction with no effective therapy. Spinal cord debris (sp) from injured spinal cord evokes secondary SCI continuously. We and other researchers have previously clarified that it is mainly bone marrow derived macrophages (BMDMs) infiltrating in the lesion epicenter to clear sp, rather than local microglia. Unfortunately, the pro-inflammatory phenotype of these infiltrating BMDMs is predominant which impairs wound healing. Hydralazine, as a potent vasodilator and scavenger of acrolein, has protective effects in many diseases. Hydralazine is also confirmed to promote motor function and hypersensitivity in SCI rats through scavenging acrolein. However, few studies have explored the effects of hydralazine on immunomodulation, as well as spontaneous pain and emotional response, the important syndromes in clinical patients. It remains unclear whether hydralazine affects infiltrating BMDMs after SCI. In this study, we targeted BMDMs to explore the influence of hydralazine on immune cells in a mouse model of SCI, and also investigated the contribution of polarized BMDMs to hydralazine-induced neurological function recovery after SCI in male mice. The adult male mice underwent T10 spinal cord compression. The results showed that in addition to improving motor function and hypersensitivity, hydralazine relieved SCI-induced spontaneous pain and emotional response, which is a newly discovered function of hydralazine. Hydralazine inhibited the recruitments of pro-inflammatory BMDMs and educated infiltrated BMDMs to a more reparative phenotype involving in multiple biological processes associated with SCI pathology, including immune/inflammation response, neurogenesis, lipid metabolism, oxidative stress, fibrosis formation, and angiogenesis, etc. As an overall effect, hydralazine-treated BMDMs loaden with sp partially rescued neurological function after SCI. It is concluded that hydralazine plays an immunomodulation role of educating pro-inflammatory BMDMs to a more reparative phenotype; and hydralazine-educated BMDMs contribute to hydralazine-induced improvement of neurological function in SCI mice, which provides support for drug and cell treatment options for SCI therapy.

Assessing Depression and Cognitive Impairment Following Stroke and Neurotrauma: Behavioral Methods for Quantifying Impairment and Functional Recovery

Rodent models of stroke and neural injury are reliable and useful tools for testing new interventions and therapeutics. In addition to physical (motor) impairment, cognitive deficits and depressive behaviors are often observed due to neurotrauma. Proper experimental design of pre- and post-assessments of these behaviors that reduce or minimize the confounding effects of motor impairment are essential for determining markers of progression of impairment or recovery. This chapter provides step-by-step laboratory protocols for assessing cognition using the Barnes maze and the novel object recognition test (NORT) and depressive-like behaviors using the sucrose preference test, the three-chambered sociability approach test, and the burrowing test.

Event-related potentials during mental rotation of body-related stimuli in spinal cord injury population

Mental rotations of body-related stimuli are known to engage the motor system and activate body schema. Sensorimotor deficits following spinal cord injury (SCI) alter the representation of the body with a negative impact on the performance during motor-related tasks, such as mental rotation of body parts. Here we investigated the relationship between event-related potentials in SCI participants and the difficulty in mentally rotating a body-part. Participants with SCI and healthy control subjects performed a laterality judgment task, in which left or right images of hands, feet or animals (as a control stimulus) were presented in two different orientation angles (75° and 150°), and participants reported the laterality of the stimulus. We found that reaction times of participants with SCI were slower for the rotation of body-related stimuli compared to non-body-related stimuli and healthy controls. At the brain level, we found that relative to healthy controls SCI participants show: 1) reduced amplitudes of the posterior P100 and anterior N100 and larger amplitudes of the anterior P200 for overall stimuli; 2) an absence of the modulation of the rotation related negativity by stimulus type and rotation angles. Our results show that body representation changes after SCI affecting both components of early stimulus processing and late components that process high-order cognitive aspects of body-representation and task complexity.

Spinal cord reserve in multiple sclerosis

BACKGROUND

The spinal cord (SC) is a preferential target of multiple sclerosis (MS) damage highly relevant towards disability. Differential impact of such damage could be due to the initial amount of SC tissue, as described for the brain parenchyma (brain reserve concept). We aimed to test the existence of SC reserve by using spinal canal area (SCaA) as a proxy.

METHODS

Brain sagittal three-dimensional T1-weighted scans covering down to C5 level were acquired in 2930 people with MS and 43 healthy controls (HCs) in a cross-sectional, multicentre study. SC area (SCA) and SCaA were obtained with the Spinal Cord Toolbox. Demographical data and patient-derived disability scores were obtained. SC parameters were compared between groups with age-adjusted and sex-adjusted linear regression models. The main outcome of the study, the existence of an association between SCaA and Patient Determined Disease Steps, was tested with scaled linear models.

RESULTS

1747 persons with MS (mean age: 46.35 years; 73.2% female) and 42 HCs (mean age: 45.56 years; 78.6% female) were analysed after exclusion of post-processing errors and application of quality criteria. SCA (60.41 mm² vs 65.02 mm², p<0.001) was lower in people with MS compared with HC; no differences in SCaA were observed (213.24 mm² vs 212.61 mm², p=0.125). Adjusted scaled linear models showed that a larger SCaA was significantly associated with lower scores on Patient Determined Disease Steps (beta coefficient: -0.12, p=0.0124) independently of spinal cord atrophy, brain T2 lesion volume, age and sex.

CONCLUSIONS

A larger SCaA may be protective against disability in MS, possibly supporting the existence of SC reserve.

Higher serum β2-microglobulin is a predictive biomarker for cognitive impairment in spinal cord injury

Objective

Recent studies have suggested that high levels of β2-microglobulin are linked to cognitive deterioration; however, it is unclear how this connects to spinal cord injury (SCI). This study sought to determine whether there was any association between cognitive decline and serum β2-microglobulin levels in patients with SCI.

Methods

A total of 96 patients with SCI and 56 healthy volunteers were enrolled as study participants. At the time of enrollment, specific baseline data including age, gender, triglycerides (TG), low-density lipoprotein (LDL), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), smoking, and alcohol use were recorded. Each participant was assessed by a qualified physician using the Montreal cognitive assessment (MoCA) scale. Serum β2-microglobulin levels were measured using an enzyme-linked immunosorbent assay (ELISA) reagent for β2-microglobulin.

Results

A total of 152 participants were enrolled, with 56 in the control group and 96 in the SCI group. There were no significant baseline data differences between the two groups (p > 0.05). The control group had a MoCA score of 27.4 ± 1.1 and the SCI group had a score of 24.3 ± 1.5, with the difference being significant (p < 0.05). The serum ELISA results revealed that the levels of β2-microglobulin in the SCI group were considerably higher (p < 0.05) than those in the control group (2.08 ± 0.17 g/mL compared to 1.57 ± 0.11 g/mL). The serum β2-microglobulin level was used to categorize the patients with SCI into four groups. As serum β2-microglobulin levels increased, the MoCA score reduced (p < 0.05). After adjustment of baseline data, further regression analysis showed that serum β2-microglobulin level remained an independent risk factor for post-SCI cognitive impairment.

Conclusions

Patients with SCI had higher serum levels of β2-microglobulin, which may be a biomarker for cognitive decline following SCI.

Psychological and Psychiatric Aspects of Brain and Spinal Cord Tumors

Central nervous system (CNS) tumors are mainly diagnosed by physical symptoms such as paralysis, visual field defect, seizure, and loss of consciousness. The psychological and psychiatric background of CNS tumors, whether in preoperative or postoperative period, has long been a neglected topic; however, lately, many authors and researchers have paid more attention to these manifestations. Neurocognition is a subset of parameters, including attention, memory, mood, emotions, language production, personality, executive function, problem-solving, calculation, and spatial cognition, making up the patient's cognitive performance. Also, it is worthy to say that neurocognition is considered a parameter of quality of life (QoL). Currently, we know that neurocognitive disorders are a group of symptoms presenting by the patients. These symptoms may be the first picture of CNS lesions, which result in incorrect treatment, a higher financial burden on the patient and health system, and finally, poorer QoL and performance scale if they are not diagnosed early. Psychological and psychiatric problems such as depression, anxiety, and phobia following the CNS tumors have two aspects. These may present before any treatment resulting from the tumoral mass effect, peritumoral edema, or cerebral tissue disruption due to the space-occupying lesion. On the other hand, we can see these features after a kind of therapy such as surgery, medical therapy, or adjuvant therapy. Sometimes, the CNS tumors lead to psychosocial complications postoperatively. Indeed, considering tumor surgery complications, some patients may find various degrees of deficits that make the patient isolated either socially or professionally. Obviously, the improvement rate and outcome of this specific situation depend on the mechanism of occurrence and its causes. For instance, postoperative symptom relief would be expected when the symptoms are related to the tumoral mass effect. Getting familiar with this constellation of the symptoms, realizing them, and then localizing them to the correct area of the CNS are very crucial. Accordingly, because of their importance in QoL, their influence on patient's survival even more than the extent of resection of the tumor, and somehow their ignorance, we will discuss different neurocognitive manifestations related to CNS tumors in this chapter.