Cardiovascular, Cerebrovascular, and Cognitive Function in Spinal Cord Injury

Study Overview
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Brief Summary
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Increased life expectancy in individuals with spinal cord injury (SCI) present clinicians with the challenge of managing the secondary complications of SCI with the chronic diseases common in an aging population. Cardiovascular disease, cerebral vascular disease, and cognitive dysfunction are among the primary challenges facing clinicians in the treatment of an aging population. Cognitive dysfunction has been reported in upwards of 60% of the SCI population, which have been primarily attributed to concomitant traumatic brain injury or pre-morbid conditions. Identifying possible modifiable risk factors which contribute to the increased prevalence of cognitive dysfunction in the SCI population is of significant clinical relevance and cardiovascular and cerebrovascular disorders have emerged as possible contributors to the cognitive disorders in the general population. These risk factors include: physical inactivity, chronically low or high blood pressure (BP), reduced blood flow to the brain, arterial stiffening, and impaired nervous system regulation of the cardiovascular system. These risk factors are particularly prominent in the SCI population as they represent a model of profound inactivity, have trouble regulating blood pressure, and suffer impaired cardiovascular regulation from their injury. In addition, we've recently reported deficits in blood flow to the brain at rest and during cognitive tests; with results being further impaired in SCI with chronically low blood pressure. Therefore the goals of this project are to determine the influence of cardiovascular and cerebral vascular responses at rest and during cognitive testing on test performance in 80 individuals with SCI compared to 50 age-matched non-SCI controls. All potential subjects will undergo a rigorous two-part screening process which consists of an initial screening via telephone and a detailed, in-person screening. Eligible subjects will be invited to participate in a 3 hour laboratory visit during which their arterial stiffness, blood pressure, heart rate, respiration rate and, blood flow to the brain will be monitored at rest and during a comprehensive series of cognitive tests. We hypothesize that blood pressure and cerebrovascular response to testing will account significantly for performance in cognitive testing that otherwise would have been attributable to SCI status.

Detailed Description
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The cognitive test battery will consists of the tests listed below, administered in the order given. Each test will be scored according to the California Verbal Learning Test (Total & SD?) Controlled oral word association test Symbol Digit Modalities Test (Oral version) Trail Making Test (Oral version) Stroop Test (W?, C?, CW?) Digit Span (Forwards, Backwards, and Sequencing) California Verbal Learning Test (LD? & Recognition?) Letter-Number Sequencing California Verbal Learning Test (LD Forced recognition?) WASI-II Sub-tests (Vocabulary, Similarities, and Matrix Reasoning)

Official Title
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Cardiovascular, Cerebrovascular, and Cognitive Function in SCI

Conditions
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Spinal Cord Injury

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Between the ages of 30 and 64 years old If SCI, the duration of injury must be greater than 1 year At least 20/60 minimum acuity in worst eye on the Snell Eye Exam A score ≥22 on the Montreal Cognitive Assessment English literate Able to provide informed consent Exclusion Criteria: Acute illness or infection Documented history of: Stroke Recent illicit drug abuse (from medical chart, within the past 6-months) Unstable or uncontrolled seizures Neurodegenerative disease including Alzheimer's disease, Parkinson's disease, Huntington's disease Severe TBI (identified by TBI screening tool) Any significant history of neurological disease/disorders: Alzheimer's disease Parkinson's disease Vascular dementia Huntington's disease Pick's disease Lewy Body Dementia Frontotemporal dementia Normal pressure hydrocephalus Brain tumor Progressive supranuclear palsy Seizure disorder Multiple sclerosis Any significant systemic illness or unstable medical condition, including: Uncontrolled diabetes mellitus, Uncorrected hypothyroidism or hyperthyroidism, Systemic cancer. History of schizophrenia or bipolar disorder or any active psychosis Alcohol or substance abuse or dependence within the past 6 months (from medical record)

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Able-Bodied Controls<br>Subjects must be between the ages of 30 and 64 years old, be English-literate and able to provide informed consent. They must score at least 20/60 minimum acuity in their worst eye on the Snell Eye Exam, and score at least 22 on the Montreal Cognitive Assessment. Subjects MUST NOT HAVE: an acute illness or infection, history of stroke, recent illicit drug abuse (<6 months), unstable/uncontrolled seizures, neurodegenerative disease, Severe Traumatic Brain Injury (as determined by TBI screening tool), any significant history of neurological disease/disorder, any significant systemic illness or unstable medical condition (uncontrolled diabetes, hypo- or hyperthyroidism, systemic cancer), history of schizophrenia or bipolar disorder or any active psychosis, or alcohol/substance abuse or dependence (<6 months). | |
| Spinal Cord Injury<br>Subjects must be between the age of 30 and 64 years old, be English-literate and able to provide informed consent. They must be at least 1 year from the date of their spinal cord injury. They must score at least 20/60 minimum acuity in their worst eye on the Snell Eye Exam, and score at least 22 on the Montreal Cognitive Assessment. Subjects MUST NOT HAVE: an acute illness or infection, history of stroke, recent illicit drug abuse (<6 months), unstable/uncontrolled seizures, neurodegenerative disease, Severe Traumatic Brain Injury (as determined by TBI screening tool), any significant history of neurological disease/disorder, any significant systemic illness or unstable medical condition (uncontrolled diabetes, hypo- or hyperthyroidism, systemic cancer), history of schizophrenia or bipolar disorder or any active psychosis, or alcohol/substance abuse or dependence (<6 months). | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic Blood Pressure (mmHg) | To determine change in systolic blood pressure from seated rest to seated cognitive testing in subjects with and without spinal cord injury. | Up to 2 years | 
| Performance on tests of information processing (WAIS-IV and Digit Span) and working memory (SDMT) | To compere cognitive performance on tests of working memory and information processing in individuals with and without spinal cord injury. | up to 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral Blood Flow Velocity (cm/second) from the middle cerebral arteries | To determine change in cerebral blood flow velocity from seated rest to seated cognitive testing in subjects with and without spinal cord injury. | Up to 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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spinal cord injury, autonomic dysreflexia, baroreceptor integrity, sympathetic integrity, vagal integrity, autonomic integrity, arterial stiffness, cognitive function, traumatic brain injury, cerebral blood flow