Daridorexant for Alzheimer Disease Prevention

This study is testing whether a sleep medication called daridorexant (which helps people stay asleep) can help prevent or delay the development of Alzheimer's disease in older adults who have sleep problems but do not yet have dementia. **You may be eligible if...** - You do not have dementia (scoring above the threshold on standard memory tests) - You have had at least 6 years of formal education - Any mental health medications you take have been stable for at least 1 month - You can provide consent in English or French **You may NOT be eligible if...** - You have already been diagnosed with dementia - You have an unstable psychiatric condition, active suicidal thoughts, or a diagnosis of narcolepsy - You have severe untreated sleep apnea or a sleep disorder called REM behavior disorder - You currently take this type of sleep medication (called a DORA), benzodiazepines, or z-drugs more than twice per week - You take certain medications that affect how drugs are broken down in the body (strong CYP3A4 inhibitors/inducers) - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.