Intensive arm rehabilitation after stroke improves functional outcomes
Intensive arm motor therapy improved modified Rankin Scale scores among a “substantial” portion of patients who had experienced a stroke, according to findings published in Neurology.
The study results demonstrated that gains in specific motor impairments correlated with a higher likelihood of improvement, the researchers noted.
“Trials of acute stroke therapies often assess benefit using the modified Rankin Scale (mRS), which covers functional outcomes, is categorized by the WHO-International Classification of Function (ICF) as a measure of activities limitations (previously called “disability”) and is accepted by the FDA as the primary endpoint for acute stroke trials,” the researchers wrote. “In contrast, trials of stroke recovery therapies often assess benefit using measures categorized as loss of body structure/function (previously called “impairment”), such as the Fugl-Meyer (FM) motor scale, and often do not even measure the mRS. The relationship between improved body structure/function (eg, FM scale) and gains in measures of activities limitations (eg, mRS) is not always evident, but a better understanding of the relationship between these two dimensions could be useful to emerging stroke recovery therapeutics.”
To examine this issue, Steven C. Cramer, MD, a stroke neurologist in the department of neurology at both the University of California Los Angeles and the University of California Irvine, and colleagues examined the impact of intensive rehabilitation on the mRS and the changes in motor impairment that correlated most with mRS gains.
Patients in the 11-site, assessor-blind study demonstrated persistent, stroke-related arm motor deficits. The researchers assessed patients before and 30 days after a 6-week daily rehabilitation course. They measured activity progress with mRS, a disability score ranging from 0 (no neurological deficits) to 6 (death), and motor progress, or body structure/function gains, with the Fugl-Meyer (FM) scale.
At baseline, patients (n = 77; 160±48 days after stroke) had median mRS scores of 3 (interquartile range [IQR], 2-3). These scores decreased to 2 (IQR, 2-3) after 30 days of therapy (P < .0001). The number of patients with an mRS score equal to or less than 2 rose from 46.8% at baseline to 66.2% after 30 days of therapy (P = .015). Patients who experienced a treatment-related improvement in mRS score demonstrated similar overall motor gains compared to those without an improvement in mRS score.
When Cramer and colleagues compared improvements in body structure/function in patients with mRS gains compared to those without such gains, they found that the groups did not differ in terms of the change in total FM motor score over the same period. In addition, the change in total FM score did not correlate with the change in mRS score or to the likelihood of an mRS score reduction.
An exploratory analysis demonstrated that improvements in specific motor impairments, including finger flexion and wrist circumduction, significantly correlated with a greater likelihood of a decrease in mRS score. Cramer and colleagues also found that the number of patients who experienced a decrease in mRS score was similar between patients who had an ischemic stroke compared with an intracerebral hemorrhage.
The researchers noted the modest sample size and minimal proportion of women enrolled limited the study results.
“Patients with a treatment-related mRS gain were more likely to show improvement in specific motor impairments, such as finger flexion and wrist circumduction,” Cramer and colleagues wrote. “This suggests that not all motor impairments have the same impact on functional outcome, and therefore improvement in motor impairments that have a stronger link to function could be targeted as a useful component of a broader rehabilitation therapy strategy.”