CLINICAL AND NEURAL FEATURES PREDICTING ARM REHABILITATION-INDUCED RECOVERY, AFTER STROKE: LONGITUDINAL COHORT STUDY

S. Salvalaggio¹, A. Turolla², A. Vedovato¹, M. Andò¹, E. Rigon¹, L. Danesin¹, F. Burgio¹, R. Pezzetta¹, M. Zorzi³, D. D'Imperio¹, S. Zago¹, P. Busan¹, G. Arcara¹, G. Ferrazzi¹, N. Filippini¹

¹San Camillo IRCCS, Venice, Italy, ²University of Bologna, Bologna, Italy, ³University of Padova, Padova, Italy

Background: Stroke is a leading cause of disability and arm impairment in the long term. Prognosis for physical therapists refers to the prediction of optimal level of functional improvement that can be expected from a patient. In this regard, clinicians need to monitor whether successful trajectory of recovery is accomplished, over time.Literature provides suggestions on specific combinations of neural and clinical outcomes able to predict upper limb (UL) motor recovery after stroke. For instance, presence of motor evoked potentials (MEPs), structural integrity of the Cortico-Spinal Tract (CST), mild neurological impairments and young age were found to be positive prognostic factors for motor recovery. Alongside, rehabilitation is a key factor in promoting functional recovery, especially when provided with high dosage of treatment. However, whether and how prognosis of UL motor recovery may be influenced by rehabilitation received has not been studied yet.

Purpose: To explore clinical, neurophysiological and rehabilitation characteristics providing valid information for a prognostic model of UL rehabilitation-induced recovery, after stroke.

Methods: Inpatients with first single ischemic/hemorrhagic, cortical-subcortical, unilateral stroke were longitudinally enrolled and assessed with Magnetic Resonance Imaging (MRI), Transcranial Magnetic Stimulation (TMS) and clinical outcome measures at admittance (T0) and after 8 weeks (T1) of rehabilitation. Linear and logistic regression models were used to investigate potential clinical-and-neural predictors of UL motor recovery and factors predicting responders to motor rehabilitation, respectively (ClinicalTrials.gov ID: NCT05423119).

Results: From august 2021 to September 2022, 146 patients were screened and 38 were enrolled. Analyses on the first 20 patients (66 ± 13 years old, 19.6 ± 29.93 months from stroke) who completed the protocol showed that patients performed 67 ± 16 hours of rehabilitation, of which 33 ± 19 dedicated to specific UL activities, on average. The presence of MEPs (TO) was found to be a predicting factor for motor improvement (R²= 0.44) according to the Fugl-Meyer Assessment for Upper Extremity (FMA-UE). Moreover, lower level of Fractional Anisotropy (R²= 0.96) in the Posterior Limb of Internal Capsule (PLIC) extracted from Diffusion Tensor Imaging (DTI) was related to higher motor improvement in the UL activity, according to the Action Research Arm Test (ARAT). Finally, higher dose of rehabilitation (R² = 0.32, AUC = 0.87) was related to higher score on ARAT and higher dose of UL-specific intervention was related to better responsiveness in gross manual dexterity (R² = 0.32) according to the Box & Blocks Test (BBT).

Conclusions: Clinical features as age, time from lesion and severity of stroke were not found to influence prediction of UL motor improvement after stroke. The higher dose of therapy is provided, the higher the improvement in gross manual dexterity is expected. Integrity of the CST is involved in motor gains and presence of MEPs allows to predict a higher probability of better motor improvement, after rehabilitation.

Implications: Providing high dose of both motor rehabilitation and UL-specific activities to patients with valid MEPs and high residual motor function at baseline would lead to higher UL motor improvement.

Funding acknowledgements: This project was funded by RF-2018-12366899 (P.I. Prof. Dante Mantini), GR-2018-12366092 (P.I. Giorgio Arcara) and from San Camillo IRCCS (Venice).

Keywords:
stroke
rehabilitation
prognosis

Topics:
Neurology: stroke
Disability & rehabilitation
Neurology

Did this work require ethics approval? Yes

Institution: San Camillo IRCCS

Committee: Comitato Etico per la Sperimentazione Clinical (CESC)

Ethics number: NeuroPro 2021.10