The two most common causes of brain injury are stroke and trauma. Both sleep and mental health problems are common after brain injury; we will investigate whether there is a relationship between poor sleep quality and worse mental health in this group. We will also follow patients up, at approximately three-monthly intervals until one year after injury, to see how sleep and mental health symptoms change over time and with recovery.

We will assess sleep in detail using questionnaires, a sleep monitor worn on the wrist, a portable brain activity sensor, and a sleep mat. We will assess mental health (neuropsychiatric) symptoms using questionnaires.

Participants will be asked to complete these assessments at baseline and at approximately 3-monthly intervals until they reach 12 months post-injury.

This data will allow us to explore the types of sleep disruption seen after brain injury and examine the association between sleep and mental health symptoms.

This is a cross-sectional and longitudinal observational cohort study to assess the relationship between sleep quality and neuropsychiatric symptoms in adults within 12 months of an acquired brain injury, including traumatic brain injury (TBI), ischaemic stroke or haemorrhage. We hypothesise that participants with poor sleep quality will have worse neuropsychiatric (mental health) symptoms and slower recovery.

Participants will be identified at least one week, but less than 12 months, after brain injury from: a) National Health Service (NHS) sites; b) advertisements; and c) previous studies where patients have consented to be contacted about future studies.

The primary aim is to test whether adults with acquired brain injury and poor sleep quality (defined as a cut-off of >5 on the Pittsburgh Sleep Quality Index; PSQI) have a greater neuropsychiatric symptom burden (assessed with the diagnostic and statistical manual of mental disorder ver sion (DSM-5) Cross-Cutting Measure Level 1 Total Score) than those with good subjective sleep quality.

Secondary outcomes will test whether both self-reported and objective markers of sleep disruption (derived from actigraphy, brain activity and sleep mat data) relate to neuropsychiatric symptoms over time.

Two optional sub-studies will assess: a) long term sleep mat derived metrics (the participant will be asked to have a sleep mat on their bed at home for one year), and b) the association between sleep and changes in motor function over time.

Baseline clinical and demographic characteristics will be gathered from medical records and/or using questionnaires.

For the main objective of the study (cross-sectional assessment), we will collect data at a single time point (baseline). Following informed consent, we will assess sleep quality using the Pittsburgh Sleep Quality Index questionnaire (PSQI) and Neuropsychiatric symptoms using the Diagnostic and Statistical Manual (DSM-5) Cross-Cutting measure (DSM-5 CCM) level 1 total score.

For the secondary objectives, we will collect data at as many time points as the participant is able and willing to complete. Assessments will be at 3-monthly intervals until the participant reaches 12 months post-injury, thus some participants will complete more assessments than others. Secondary measures regarding sleep and neuropsychiatric symptoms will be assessed with self-report questionnaires at each time point: Pittsburgh Sleep Quality Index questionnaire (PSQI), sleep diary (SD; daily for 2 weeks), insomnia severity index (ISI), Fatigue Severity Scale (FSS), patient health questionnaire (PHQ-8), generalized anxiety disorder questionnaire (GAD-7), DSM-5 Cross-Cutting measure (DSM-5 CCM) Level 1 (total), primary care post-traumatic stress disorder questionnaire (PC-PTSD). We will also obtain information regarding the patient's location at the time of assessment (e.g. hospital, neurorehabilitation unit, home), medications and any sleep or mental health treatments they have received.

We will collect 'objective' sleep measures which will include using a waterproof actigraphy monitor worn on the least-affected wrist (2 weeks at each assessment period), a portable brain activity (electroencephalography) monitor to wear on their head during sleep (3-5 nights at each timepoint) and a sleep mat which goes under the bed mattress (2 weeks at each timepoint).

There are two optional sub-studies:

1. For a subset of participants we will provide a sleep mat to keep under their mattress continuously until they reach 12 months post-injury. This is to explore changes in sleep continuity/disruption and sleep timing long-term.
2. For a subset of participants we will assess motor impairment/function of the upper limb (arm) and lower limb (leg) at each time point using clinical/research assessments: the Fugl Meyer assessment, Action Research Arm Test, Box and Blocks test, and the Rivermead Mobility Index.

Inclusion Criteria:

• Willing and able to give informed consent for participation in the study.
• Aged 18 years or above.
• At least one week, but less than 12 months post-injury
• Clinical diagnosis of acquired brain injury (stroke, haemorrhage or traumatic).
• Participants with Traumatic Brain Injury will have a Mild (probable) or Moderate-severe (definite) brain injury according to the Mayo classification
• Participants must be willing to consent to us contacting their general practitioner (GP) or direct care team if we have concerns about their mental health

Exclusion Criteria:

• Brain injury not caused by trauma, haemorrhage or stroke
• Previous brain injury.
• Other relevant neurological conditions which could affect outcome measures (e.g., Parkinson's or Alzheimer's disease)
• No stable and suitable place to sleep

Adult patients, age 18 years or over (no upper age limit) within one year of acquired brain injury (stroke, haemorrhage, trauma)

Anonymous data will be available upon reasonable request to Melanie Fleming

Data will be available following publication or public release of the main findings, for approximately 2 years.

Anonymous data will be available upon reasonable request to the Principal Investigator, using file transfer (e.g. Microsoft OneDrive).