Digital Sleep Therapy for Older Adults with Cognitive Impairment

This study aims to determine the efficacy of digital Behavioural Therapy for Insomnia (dBTi) compared to online sleep health education (control) at reducing insomnia symptom severity (Insomnia Severity Index: ISI) in older adults (50+ years) with subjective cognitive impairment from baseline compared to week 8.

Insomnia is a highly prevalent sleep disorder affecting up to 10% of the adult population and reports of over 40% in the older population. Current insomnia treatments focus heavily on symptom management with cognitive behavioural therapy for insomnia (CBTi), in both digital and face-to-face form as the recommended first-line treatment. Despite the strong evidence for digital CBTi, there are a lack of data related to older people and whether digital brief behavioural therapy is efficacious in this population. Recent work shows that sleep plays a critical role in optimising brain function and sleep disturbance is highly prevalent in individuals with cognitive impairment.

The investigators will conduct a fully online study comparing 3-weeks of digital brief behavioural therapy for insomnia (dBBTi) (in addtiotion to an extra optional 3 weeks) against online sleep health education. Participants will be recruited, screened and determined eligibility and consent will be conducted online. Participants will be randomly allocated to either dBBTi delivered via a mobile application called SleepFix or wait-listed control. The SleepFix mobile application delivers sleep restriction therapy using a 4 stage approach to improve sleep efficiency. The control will consist of 3 online sleep health education modules provided bi-weekly with information about sleep and sleep hygiene without any specific insomnia therapy. Participants will be recruited using social media and directed to a website to determine eligibility and then provided access to either the dBBTi (SleepFix) or the control with a link to the first online module.

At baseline, all participants will complete self-reported measures of insomnia, cognition ,sleep, fatigue, sleepiness , anxiety, depression, quality of life and digital health literacy. These will be repeated at follow-up at weeks 8, 16.

Eligibility Criteria:
Inclusion Criteria:

* Aged 50 years and older
* Insomnia Severity Index score ≥10
* Self-reported subjective cognitive impairment as defined as moderate subjective cognitive complaints (i.e. answers YES to have cognitive concerns OR thinking and memory skills are worse than same-age peers on the online screening)
* English speaking
* Access to a smartphone and willingness/proficiency to use a mobile app for healthcare
* Able to give informed online consent

Exclusion Criteria:

* Neurological (e.g. Parkinson's, epilepsy) and major psychiatric disease (e.g. current major depression), dementia, history of cerebrovascular events (stroke, TIA); history of head injury with loss of consciousness \> 30mins;
* Self-reported jetlag symptoms due to travel in the last 7 days;
* Current illicit substance use or alcohol intake suggestive of a hazardous or harmful pattern;
* Shift-work;
* Medical conditions with known effects on cognition and sleep (e.g. cancer with chemotherapy);
* Diagnosed obstructive sleep apnoea, or other sleep disorder including REM Sleep Behaviour Disorder, Restless Legs Syndrome or Narcolepsy.