This study will explore whether sleep in stroke survivors is improved with digital cognitive behavioural therapy for insomnia (Sleepio), in comparison to treatment as usual, and will explore whether changes in sleep relate to changes in overnight consolidation of motor learning.

Stroke is one of the leading causes of adult disability. Rehabilitation of movement after stroke depends on motor learning. Motor learning involves not only improvement during practice but also offline improvement, or consolidation, that occurs after practice. Consolidation of learning depends on good sleep quality. However, sleep is disrupted long-term after stroke and patients with poorer sleep show worse rehabilitation outcomes.

Cognitive behavioural therapy for insomnia (CBT) is the recommended first line treatment for sleep problems. "Sleepio" is a digital CBT programme which is effective across a range of clinical populations. This study aims to test the efficacy of digital CBT for reducing insomnia symptoms after stroke, in comparison with usual care alone. To explore the possibility that sleep interventions might enhance rehabilitation outcomes via their impact on consolidation of motor learning, the study will additionally test for differences in consolidation between groups, and explore whether changes in sleep measures are associated with changes in consolidation.

Participants will be randomised to either receive digital CBT for insomnia (in addition to usual care) or receive treatment as usual alone (2:1 treatment to control ratio). The primary outcome is the score on the 8-item Sleep Condition Indicator, 10 weeks following randomisation. Secondary outcomes include behavioural measures of overnight motor consolidation assessed as the change in motor task performance from training to retest, sleep disruption assessed with actigraphy, and depression and fatigue using the Patient Health Questionnaire (PHQ9) and the Fatigue Severity Scale respectively.

In addition to this, to explore the feasibility of delivering rehabilitation following the sleep improvement programme, an optional 4 weeks of upper limb motor training at home will be offered to all participants (regardless of group allocation) after follow-up. Outcomes of adherence to the training and upper limb function will be assessed.

Inclusion Criteria:

• Willing and able to give informed consent for participation in the study
• Aged 18 years or above.
• Clinical diagnosis of stroke affecting the upper limb, with sufficient movement to perform the motor learning task
• Discharged from inpatient care
• Interest in accessing a programme with the aim of improving sleep quality
• Reliable access to the internet

Exclusion Criteria:

• Other neurological condition affecting movement (e.g. Parkinson's Disease, Multiple Sclerosis)
• Diagnosed, untreated, sleep disorder (e.g. Sleep Apnea)
• Uncontrolled seizures
• Planned inpatient admission (e.g. for rehabilitation) in the next 4 months that would impact ability to engage with the Sleepio programme
• Engagement in psychological therapy for insomnia in the past 12 months
• Pregnancy

De-identified data are available upon reasonable request

Following publication of results

Available upon reasonable request

Randomisation and facilitation of the intervention will be performed by a research assistant, and the person analysing the data will be blinded to group allocations.