a novel strategy to decrease fall incidence post-stroke

Conditions: Stroke

Summary: approximately 15,000 veterans are hospitalized for stroke each year with new cases costing an estimated $111 million for acute inpatient, $75 million for post-acute inpatient, and $88 million for follow-up care over 6 months post-stroke. contributing to these costs is the incidence of falls. falls are a costly complication for veterans with stroke as they lead to an increased incidence of fractures, depression, and mortality. new strategies are needed to help veterans post-stroke regain their ability to safely walk without increasing their risk of falling as well as readily identify those who are a fall risk. this study addresses both of these needs as it will 1) investigate a new treatment approach, backward walking training, to determine if it will decrease fall incidence in the first year post-stroke and 2) determine if backward walking speed early after a stroke can identify those that are at risk for future falls.

approximately 15,000 veterans are hospitalized for stroke each year. persistent walking and balance deficits contribute to long-term disability and a high incidence of falls. falls are a common and costly complication of stroke; between 40% and 70% of affected individuals fall within the first year. falls lead to fear of falling, limitations in self-care and increased dependence. of greater concern, they lead to serious adverse events, including fractures, depression and mortality. a primary goal of stroke rehabilitation is to improve mobility despite persistent motor, balance and visual-spatial deficits. however, this goal has a down side since it increases fall risks. here, the investigators propose a novel therapeutic strategy to improve ambulation while decreasing the risk of falls: backward walking training (bwtraining). the investigators' central hypothesis is that a 6-week bwtraining program at 2-months post-stroke is superior to standard care in reducing falls within the 1st year post-stroke. identification of those at risk for falling is a necessary component of post-stroke rehabilitation to implement pro-active measures to decrease risk once individuals rejoin community living. recent research in a cohort of elderly adults determined that maximal backward walking speed (bwspeed) (not forward) identified individuals that had experienced a fall in the previous six months,6 suggesting that bwspeed could be a simple, inexpensive screening tool to identify individuals at risk of falling. with a randomized, blinded design, the investigators propose to prospectively assess the value of bwspeed as a tool to predict future falls. a notable post-stroke conundrum is that increased mobility may increase fall risk.5 on the other hand, limiting mobility leads to a multitude of inactivity-associated deficits, including recurrent stroke. to date, no intervention has demonstrated efficacy for improving walking while minimizing fall risk. bwtraining may be a simple and effective intervention to achieve both goals. in the investigators' recent randomized controlled pilot trial (rct), individuals with sub-acute stroke who participated in a bwtraining demonstrated 3-fold improvement in backward and forward walking speed and fall self-efficacy. further, bwtraining caused 75% greater improvement in balance versus those in a dose-matched balance training group. at the 3-month follow-up assessment, bwspeed of the bwtraining group averaged 0.63 m/s, exceeding the threshold for fall risk in elderly adults. given the success of the investigators' pilot intervention, a larger and more rigorous trial is needed to demonstrate reduced fall incidence over an extended follow-up period. the investigators designed this rct to address three specific aims: aim #1: test the hypothesis that 1-year fall incidence is decreased for participants randomized to bwtraining administered at 2-months post-stroke (versus usual care comparison group). hypothesis #1a: bwtraining at 2-months post-stroke reduces the number of falls over the next year. hypothesis #1b: bwtraining at 2-months post-stroke increases gait speed, improves balance and increases balance confidence over the next year. aim #2: test the hypothesis that bwtraining at 2 months (immediate) vs. 1-year (delayed) post-stroke is more effective at improving bwspeed. hypothesis #2a: bwspeed improvement from 2- to 14-months post-stroke is greater when bwtraining is delivered at 2 months versus 1 year post-stroke. hypothesis #2b: improvements in forward gait speed, functional gait assessment and activities-balance confidence scale from 2- to 14-months post-stroke are greater when bwtraining is delivered at 2 months versus 1 year post-stroke. aim #3: this exploratory aim will test the hypothesis that bwspeed at 2-months post-stroke is a significant predictor of fall incidence over the next year 1 year period, after adjusting for other covariates. hypothesis #3: bwspeed at 2-months will be a significant predictor of fall incidence during the first year post-stroke, after adjusting for other covariates. this study is significant since it concerns a novel strategy to improve ambulation while minimizing the risk of falling after a stroke. bwtraining is highly novel, is easy to administer and exciting preliminary data suggest that is has major potential as a therapeutic tool. in addition, the investigators will determine the potential of bwspeed (a simple, clinically relevant screening tool) to identify those at risk for future falls.

Eligibility criteria:
inclusion criteria: * berg balance scale \< 42 * self-selected 10 meter gait speed \< 0.8 m/s * diagnosis of unilateral stroke * \> 2 months \< 4 months post-stroke * able to ambulate at least 10 feet with maximum 1 person assist * medically stable * 18-85 years of age * physician approval for patient participation exclusion criteria: * presence of neurological condition other than stroke * serious cardiac conditions * hospitalization for myocardial infarction or heart surgery within 3 months * history of congestive heart failure * documented serious and unstable cardiac arrhythmias * hypertrophic cardiomyopathy * severe aortic stenosis * angina or dyspnea at rest or during activities of daily living * anyone meeting new york heart association criteria for class 3 or class 4 heart disease will be excluded * severe arthritis or orthopedic problems that limit passive ranges of motion of lower extremity * knee flexion contracture of -10 * knee flexion range of motion \< 90 * hip flexion contracture \> 25 * ankle plantar flexion contracture \> 15 * severe hypertension with systolic greater than 200 mmhg and diastolic greater than 110 mmhg at rest, that cannot be medically controlled into the resting range of 180/100 mmhg * pain upon ambulation * receiving physical therapy services for mobility and/or gait * living in a skilled nursing facility * unable to ambulate at least 150 feet prior to stroke, or experienced intermittent claudication while walking less than 200 meters * history of serious chronic obstructive pulmonary disease or oxygen independence * non-healing ulcers on the lower extremity * uncontrollable diabetes with recent weight loss, diabetic coma or frequent insulin reactions * on renal dialysis or presence of end stage liver disease * pulmonary embolism within previous 6 months * history of major head trauma * history of sustained alcoholism or drug abuse in the last six months * intracranial hemorrhage related to aneurysmal rupture or an arteriovenous malformation * current enrollment in a clinical trial to enhance stroke motor recovery

Keywords: rehabilitation gait postural balance exercise accidental falls kinesiology, applied