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.
- Backward Walking Training Behavioral
Intervention Desc: Backward Walking Training will occur both on a treadmill and overground. In brief, BWTraining will consist of 20-30 minutes of step training with a Body Weight Support and Treadmill system (BWST), rest periods provided as warranted, with manual assistance provided by trainers, followed by 15 minutes of overground gait training. A 20-30 min period of actual stepping is the goal for the intervention sessions on the treadmill with rest periods as needed. Each training session may last up to 1 hour and 30 minutes including time for warm-up, stretching, and cool down. Participants will be fitted with a harness around their hips and torso, which will be attached to an overhead support system directly above the treadmill. From a stationary position, the treadmill belt will gradually be increased in speed with intervention trainers assisting participant to step backward with their paretic leg, their non-paretic leg (if needed) and at the hips for weight-shift. ARM 1: Kind: Experimental Label: Immediate Backward Walking Training Description: Individuals will participate in 18 sessions of Backward Walking training immediately following baseline assessment. ARM 2: Kind: Experimental Label: Delayed Backward Walking Training Description: Individuals will participate in 18 sessions of Backward Walking training at 1-year post-strokeD
- Allocation: Randomized
- Masking: Single Blind (Outcomes Assessor)
- Purpose: Treatment
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Fall incidence (number of falls)||Change between baseline and 1-year post-stroke||No|
|Secondary||10 Meter Walk Test||Change between baseline and 1-year post-stroke||No|
|Secondary||3-Meter Backward Walk test||Change between baseline and 1-year post-stroke||No|
|Secondary||Functional Gait Assessment||Change between baseline and 1-year post-stroke||No|
|Secondary||Activities-Specific Balance Confidence Scale||Change between baseline and 1-year post-stroke||No|
|Secondary||Berg Balance Scale||Change between baseline and 1-year post-stroke||No|
|Secondary||Lower-Extremity Fugl-Meyer Motor Score||Change between baseline and 1-year post-stroke||No|
|Secondary||Four-Step Square Test||Change between baseline and 1-year post-stroke||No|
|Secondary||Stride time||Change between baseline and 1-year post-stroke||No|
|Secondary||Stride length||Change between baseline and 1-year post-stroke||No|
|Secondary||Step time||Change between baseline and 1-year post-stroke||No|
|Secondary||Step length||Change between baseline and 1-year post-stroke||No|
|Secondary||Step width||Change between baseline and 1-year post-stroke||No|
|Secondary||Kinesiologic assessment of walking||Change between baseline and 1-year post-stroke||No|