Lemborexant for Insomnia in a Patient With Dementia: An N-of-1 Trial

Background & Rationale Insomnia is a highly common, chronic disorder that is distressful for the patient but also for caregivers and can give rise to a heavy burden on the healthcare team. Sleeping aids like benzodiazepines and other sedatives (e.g., zolpidem, zopiclone) have been widely used to help treat insomnia. However, sleeping aids are also known to cause adverse drug reactions such as drowsiness and dizziness, that increases the risk of falls, driving impairment, visual impairment, cognitive impairment, and upon discontinuation may cause paradoxical rebound insomnia, delirium, and nightmares all of which exacerbate the initial insomnia. All of the negative aspects of sleeping aid use are exaggerated for older, frail adults.

Some patients experience an early (young-age) onset dementia with a substantial component of insomnia. Due to the many risks associated with traditional sleeping aids they are often inappropriate in adults living with cognitive impairment and/or frailty. Lemborexant comes from a new class of medications for insomnia. Lemborexant is a dual orexin receptor antagonist that blocks the binding of wake-promoting neuropeptides orexin A and orexin B to their receptors orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R), which is thought to suppress wake drive. Unlike other traditional sleeping aids, lemborexant has not shown to be significantly associated with driving impairment, rebound insomnia, or dependence/withdrawal symptoms. Also, in clinical trials it only rarely causes the types of adverse events associated with benzodiazepines and other traditional sedatives and is less often associated with discontinuations due to adverse events.

While lemborexant is available on the Canadian market it is unclear how this medication will be tolerated by patients living with an early onset dementia. Understanding the effectiveness, tolerability, and safety of lemborexant will be helpful in an N of 1 trial to understand the details of effect and effectiveness in individual patients living with dementia and insomnia.

Hypothesis The investigators hypothesize that lemborexant will be effective and safe in the treatment of insomnia in adults living with both early-onset dementia and concomitant sleep difficulty.

Objective The objective of this study is to evaluate lemborexant for efficacy and safety as a sedative medication for insomnia in adults living with both early-onset dementia and insomnia.