Exercise and Brain Health

A major public health problem in aging is that about half of all stroke survivors have significant cognitive problems, called vascular cognitive impairment, nondementia (VCIND) and also a 10fold increased risk of going on to develop full dementia. Investigators at University of Maryland and VA Maryland Exercise and Robotics Center of Excellence (MERCE) have developed exercise programs for individuals that have suffered a disabling stroke that improve cardiovascular fitness levels, walking function, balance, and can reverse impaired glucose tolerance (prediabetic state) and non-insulin dependent diabetes in nearly 60% of stroke patients. Our most recent randomized studies provide the first evidence that aerobic exercise (cardiovascular) can improve selected aspects of cognitive function that typically decline with aging, and can increase indirect measures of blood flow to the brain. All of these findings provide hope that exercise can improve brain health by reducing recurrent stroke including silent strokes (9/10 stroke are silent), and improving cognitive function. Yet, no studies to our knowledge have shown that exercise training can improve these elements of brain health in individuals that have had a minor stroke, silent strokes, or are at great risk of stroke due to the presence of cerebrovascular risk factors (e.g., hypertension, prediabetes, etc.). Research studies in this pilot clinical demonstration project are designed to: 1) provide new insights into the potential role for exercise to improve brain health in aging and after minor stroke or at risk for stroke by using advanced brain imaging techniques; 2) extend our findings in exercise and brain health to a population with cerebrovascular disease, including those with less severe neurological deficits; those with cerebrovascular risk factors, minor strokes, transient ischemic attack (neurological deficits resolved, but still at high risk for further events), or silent strokes, which are extremely common and predictive of developing cognitive decline and dementia. Furthermore, the investigators are dedicated to testing exercise programs that can reach out to the community. Therefore, the investigators propose to use the same low intensity exercise class format that the investigators already have implemented safely and effectively at County Senior Centers in Maryland over the last 4 years for more disabled stroke patients, toward the training of these minimally disabled or nondisabled older individuals with silent or minor cerebrovascular disease. The results of this study will lay the groundwork for community partnering and broader dissemination providing exercise programs designed to preserve and improve brain health for those at high risk of vascular disease and cognitive decline in aging. The hypothesis is that a 6 month supervised exercise class will improve brain function and cognitive function among individuals with cerebrovascular risk factors, minor stroke, TIA, or silent stroke as indicated by measures before and after training of 1) written and computer - based cognitive function (memory and thinking) and mood tests and 2) MRI pictures of the brain to see if blood flow is increased or damage due to old strokes and aging is reduced by the exercise training.

Individuals with cerebrovascular risk factors (e.g., hypertension, diabetes), minor stroke (nondisabling stroke in terms of community or home walking capability), TIA (warning stroke), or silent stroke (seen by brain imaging, but no paralysis or obvious stroke signs or symptoms) will be entered into a 6 month duration exercise class.

Initial medical and neurological evaluation will be conducted by a credentialed Clinician to assure that individuals are eligible and that they are medically and neurologically approved for participation in a low intensity aerobic exercise class. All subjects will have approval of their primary care provider, documenting their awareness and medical approval for their patient to enter into a low to moderate exercise intensity class. This is the same medical clearance that is already Institutional Review Board approved and is in use for the similar exercise class for stroke and neurologic disability in Howard County Department of Aging Senior Centers. Before starting the exercise, all subjects will be given a series of baseline testing: 1) walking and balance tests to characterize their mobility performance capacity (timed walks, Short Physical Performance Battery, Functional Reach, Berg Balance Test, modified dynamic gait index, and 4 square stepping, 2) a 12 hour battery of written and computer based cognitive function and mood tests and questionnaires, and 3) MRI that lasts about 1 hour that includes pictures of the brain . All of these tests will be repeated at midpoints (i.e., 3 months) and at the end of the training program (6 months, MRIs are performed only at baseline and 6 months). The exercise class will consist of supervised walking as well as bar and chair exercises to address upper and lower extremity function. The class will occur 3 times per week for 6 months.

Individuals are instructed to perform select parallel exercises at home the remaining days of the weeks and record activities in a homework logbook.

This protocol is being designed in a modular fashion to collect the same outcomes at baseline and post all other MERCE exercise and robotics interventions.