Matthew Edwardson, MD

Lohse KR, Lang CE, and Boyd LA. Is More Better? Using Metadata to Explore Dose–Response Relationships in Stroke Rehabilitation. Stroke. 2014

The more time spent in rehabilitation therapy, the better the recovery.  Although widely believed by the stroke community, this theory becomes less clear after exploring the scientific evidence.  For example, one study suggested that high doses of intense occupational therapy shortly after stroke actually led to worse outcomes.  In addition, compared to acute stroke trials, most rehabilitation trials enrolled only a small number of subjects.  How generalizable could the results really be?  Lohse and colleagues tackled this problem using a meta-data approach combining the results of high quality stroke rehabilitation trials.  They discovered that more time in therapy does indeed improve recovery, but the timing of delivery post-stroke may be less important.

The authors identified 37 high quality randomized controlled stroke rehabilitation trials that differed in the amount of therapy delivered between groups.  Outcome measures for each study were converted to standard effect-sizes in order to combine results.  Timing of therapies post-stroke varied considerably with a mean of ~1 year.  Overall results showed improved outcomes in those receiving more therapy (g = 0.35, [0.26, 0.45], p < 0.001).  Regression modeling suggested significant improvement for every 10 additional hours of therapy independent of when therapy was started post-stroke.  There was weak evidence to suggest that every additional 10 hours of therapy may provide diminishing returns.

This study provides strong evidence that time spent in rehabilitation therapy matters and raises several questions with regard to current clinical practice.  Insurance reimbursement largely dictates time allotted to inpatient and outpatient therapies in the U.S.  Should we be advocating for more time?  At what point does more therapy provide no clinically significant benefit?  By taking into account that the control groups in all of these studies received a standard amount of time in therapy, it would appear that under-treatment is the norm and advocating for more time is warranted.  While the current study suggested no difference with regard to the timing of therapy post-stroke, many of us feel this question has not been adequately addressed in human trials.  Animal stroke models suggest earlier is better.  Complicating matters is the lack of a one-size-fits-all approach to stroke rehab.  Patients enrolled into stroke rehabilitation trials typically have pure-motor stroke and a moderate degree of weakness.  Those with very mild or very severe strokes may not benefit from additional therapy.  In summary, more is generally better, but the best approach in clinical practice remains in debate.