Intensive therapy within critical time window fastens rehabilitation after stroke: Study

Restoration of human brain function after an injury is a signal challenge for translational neuroscience. Rodent stroke recovery studies identify an optimal or sensitive period for intensive motor training after stroke: near-full recovery is attained if task-specific motor training occurs during this sensitive window.

A group of researchers extended these findings to adult humans with stroke in a randomized controlled trial applying the essential elements of rodent motor training paradigms to humans. Stroke patients were adaptively randomized to begin 20 extra hours of self-selected, task-specific motor therapy at ≤30 d (acute), 2 to 3 mo (subacute), or ≥6 mo (chronic) after stroke, compared with controls receiving standard motor rehabilitation. Upper extremity (UE) impairment assessed by the Action Research Arm Test (ARAT) was measured at up to five-time points.

The primary outcome measure was ARAT recovery over 1 y after stroke.

The results of the study are as follows:

· By 1 year the researchers found significantly increased UE motor function in the subacute group compared with controls.

· The acute group compared with controls showed smaller but significant improvement.

· The chronic group showed no significant improvement compared with controls.

· Thus task-specific motor intervention was most effective within the first 2 to 3 months after stroke.

· The similarity to rodent model treatment outcomes suggests that other rodent findings may be translatable to human brain recovery.

Thus, the researchers concluded that these results provide empirical evidence of a sensitive period for motor recovery in humans.

Reference:

Critical Period After Stroke Study (CPASS): A phase II clinical trial testing an optimal time for motor recovery after stroke in humans by Dromerick A et.al published in the Proceedings of the National Academy of Sciences of the United States of America.

DOI: 10.1073/pnas.2026676118