Digital CBT-I feasibility study protocol targets insomnia in cognitive impairment, exploring neurodegeneration markers

Insomnia is highly prevalent in older adults and strongly associated with increased risk of cognitive impairment and dementia, including Alzheimer's disease. Emerging evidence suggests a bidirectional link, where sleep disturbance may contribute to neurodegeneration by impairing the glymphatic system's clearance of neurotoxic metabolites like β-amyloid and tau proteins. Current interventions often fall short in addressing this complex interplay, highlighting the need for accessible, effective strategies that might mitigate disease progression.

This paper describes the protocol for the Randomised Evaluation of Sleep in Cognitive Impairment Trial (REST), a feasibility study. It will evaluate a digital Cognitive Behavioural Therapy for Insomnia (CBT-I) intervention in older adults experiencing cognitive impairment. The study design includes an 8-week treatment phase, with participants randomized to either the digital CBT-I or a control arm. Primary endpoints focus on assessing the feasibility and acceptability of the intervention, including recruitment, retention, and adherence rates. Secondary endpoints will measure changes in sleep parameters, cognitive performance, and quality of life.

As a protocol paper, this study does not report findings but outlines the intended outcomes. The REST protocol aims to assess the feasibility and acceptability of the digital CBT-I intervention among older adults with cognitive impairment. Primary outcomes will include recruitment rates, retention rates, adherence to the 8-week intervention, and completion rates of outcome measures. Secondary outcomes will involve changes in sleep parameters (e.g., sleep efficiency, total sleep time), cognitive performance (e.g., attention, executive function, memory), and quality of life. The study will also explore preliminary effects on neuroimaging markers related to amyloid deposition and tau proteins, and neuroinflammation to inform future efficacy trials.