Sleep and motor learning in stroke (SMiLES): a longitudinal study investigating sleep-dependent consolidation of motor sequence learning in the context of recovery after stroke

Abstract

Introduction: There is growing evidence that sleep is disrupted after stroke, with worse sleep relating to poorer motor outcomes. It is also widely acknowledged that consolidation of motor learning, a critical component of poststroke recovery, is sleep-dependent. However, whether the relationship between disrupted sleep and poor outcomes after stroke is related to direct interference of sleep-dependent motor consolidation processes, is currently unknown. Therefore, the aim of the present study is to understand whether measures of motor consolidation mediate the relationship between sleep and clinical motor outcomes post stroke.

Methods and analysis: We will conduct a longitudinal observational study of up to 150 participants diagnosed with stroke affecting the upper limb. Participants will be recruited and assessed within 7 days of their stroke and followed up at approximately 1 and 6 months. The primary objective of the study is to determine whether sleep in the subacute phase of recovery explains the variability in upper limb motor outcomes after stroke (over and above predicted recovery potential from the Predict Recovery Potential algorithm) and whether this relationship is dependent on consolidation of motor learning. We will also test whether motor consolidation mediates the relationship between sleep and whole-body clinical motor outcomes, whether motor consolidation is associated with specific electrophysiological sleep signals and sleep alterations during subacute recovery.

Ethics and dissemination: This trial has received both Health Research Authority, Health and Care Research Wales and National Research Ethics Service approval (IRAS: 304135; REC: 22/LO/0353). The results of this trial will help to enhance our understanding of the role of sleep in recovery of motor function after stroke and will be disseminated via presentations at scientific conferences, peer-reviewed publication, public engagement events, stakeholder organisations and other forms of media where appropriate.

Trial registration number: ClinicalTrials.gov: NCT05746260, registered on 27 February 2023.

Keywords: neurophysiology; rehabilitation medicine; stroke.

Figure 1

Consent process, including capacity to consent decision framework.

Figure 2

Flowchart of the trial timeline and assessments. ARAT, Action Research Arm Test; BMI, body mass index; EEG, electroencephalography; FMA, Fugl-Meyer Assessment; mRS, modified Rankin Scale; NIHSS, National Institute of Health Stroke Scale; PHQ-8, Patient Health Questionnaire-8; RMI, Rivermead Mobility Index; SAFE, Shoulder Abduction Finger Extension; SCI, Sleep Condition Indicator; SRTT, Serial Reaction Time Task; STOP-Bang, Obstructive Sleep Apnoea Questionnaire; TMS, transcranial magnetic stimulation; 9HPT, Nine Hole Peg Test.

Figure 3

Predict Recovery Potential algorithm (PREP2), included with permission, under license CC BY-NC-ND 4.0 (https://presto.auckland.ac.nz). The algorithm uses neurological and clinical biomarkers to predict four different categories of potential recovery outcomes at 3 months after stroke. MEP, motor evoked potential; NIHSS, National Institute of Health Stroke Scale; SAFE, Shoulder Abduction Finger Extension Score.