Sleep Disturbance in MCI: A Study of a Cognitive Behavioural Therapy Digital Intervention

This study aims to determine the feasibility of a randomized-controlled trial of digital cognitive behavioural therapy for insomnia (CBT-I) for sleep and cognitive performance in older adults with MCI and insomnia symptoms (50-80 years). The trial will be completed online, and participants will be recruited from the community across Australia.

Insomnia is a highly prevalent sleep disorder which affect approximately 10% of the adult population and 40% of the older population. Further, insomnia has been linked to an increased risk of developing dementia. Currently, the recommended first-line treatment for insomnia is cognitive behavioural therapy for insomnia (CBT-I), in both face-to-face and digital form. Despite the strong evidence for digital CBT-I, there are insufficient data regarding the benefits and effectiveness of digital CBT-I in older people with mild cognitive impairment (MCI).

The investigators will conduct a fully online study comparing 6-weeks of digital behavioural therapy for insomnia (CBT-I) against online sleep health education. Participants will be recruited using social media, as well as from memory clinics. Participants will be screened and determined eligibility and consent will be conducted online. Subsequently, participants will be randomly allocated to either digital CBT-I delivered via an application called Sleepio or wait-listed control. The Sleepio app is a sleep-improvement program that uses cognitive behavioural therapy techniques to improve insomnia symptoms. The wait-listed control will consist of 3 modules of an online Sleep Health Education package delivered fortnightly with non-tailored basic sleep information. They will be directed to a website to determine eligibility and then provided access to either the digital CBT-I (Sleepio) or the wait-listed control with a link to the first online module.

At baseline, all participants will complete self-reported measures of subjective cognitive complaints, insomnia, fatigue, sleep, depression, quality of life, and digital health literacy. Also, they will complete three web-based cognitive assessments that measure memory, processing speed, and executive functioning. These will be repeated at follow-up at weeks 12

Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of MCI as defined by a neuropsychologist.
* Able to provide informed electronic consent.
* Fluent English literacy.
* Adults aged between 50-80 years.
* Insomnia symptoms as indicated by a score \>10 on the Insomnia Severity Index (ISI).
* Regular computer, smartphone, or tablet use, with internet access.

Exclusion Criteria:

* Previous diagnosis of dementia or a score on the brief Montreal Cognitive Assessment of \<18.
* Previous major head injury, cerebrovascular events (stroke, TIA), or loss of consciousness ≥ 30 minutes.
* Previous or current neurological disorder diagnosis (e.g. Parkinson's, multiple sclerosis, epilepsy).
* Current illicit substance use or harmful alcohol intake (Alcohol Use Disorders Identification Test Consumption (AUDIT-C) score \> 8).
* Current severe major depression diagnosis as defined by a score \>20 on the Patient Health Questionnaire (PHQ-9) and/or suicidal ideation (score of \>1 on Q9 of the PHQ-9), or severe psychiatric or developmental disorders (e.g. Schizophrenia, bipolar disorder, autism).
* Major sleep disorders (e.g. narcolepsy, severe restless legs syndrome, and rapid eye movement (REM) sleep behaviour disorder)
* Commencement of continuous positive airway pressure therapy, antidepressants, melatonin or engaged in CBT or psychological interventions within the prior 4 weeks.
* Shift workers, recent (within 30-days) transmeridian travel.
* Older adults with a risk of an increase in daytime sleepiness and decreased alertness (e.g. professional drivers or those who operate heavy machinery).
* Any contraindication to sleep deprivation therapy.
* Currently participating in or has participated in a research study of an investigational agent or device within 4 weeks of enrolment.
* Any medication that has been used to assist sleep for three or more nights per week (e.g. benzodiazepines, sedative hypnotics, opioids) or at the discretion of the clinician.