Efficacy of CBT-I and Lemborexant Medication for Different Subtypes of Chronic Insomnia

Inclusion Criteria:

• 18 years of age or older at the time of enrolment

• Meeting Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria forinsomnia disorder (Duke Sleep Interview), with total Insomnia Severity Index (ISI)score > 10, and score ≥ 2 on either the interference or distress item

• Minimal symptoms of anxiety and/or depression with Patient Health Questionnaire (PHQ-9) > 4 and/or Generalized Anxiety Disorder (GAD-7) > 4

• Ability to read and understand French or English

• Ability to use a smartphone, tablet, or computer, and access to home internetconnection

Exclusion Criteria:

• Presence of a lifetime diagnosis of any psychotic or bipolar disorder

• Untreated psychiatric disorder (e.g., major depression) or risk for suicide

• Substance/alcohol use disorder within the past year

• Any life-threatening or progressive medical illness (e.g., cancer, chronicobstructive pulmonary disease) or neurological degenerative disease (e.g., dementia)

• Current use of sleep-promoting medications (prescribed or over-the-counter) orcannabis-derived products for sleep more than two nights per week

• Current use of tricyclic antidepressants, monoamine oxidase inhibitors, or atypicalantidepressants

• Reported diagnosis of sleep disorder other than insomnia (e.g., obstructive sleepapnea, restless legs syndrome, rapid eye movement behavior disorder, delayed phasesleep disorder, narcolepsy)

• Total score > 5 on the Stop-Bang Questionnaire and/or clinical symptoms suggestiveof sleep apnea (excessive daytime sleepiness), or Epworth score > 10, restless legssyndrome or other signs of other sleep disorders

• Atypical sleep schedules (i.e., habitual bedtimes later than 2:00 AM and risingtimes later than 10:00 AM on more than two days/nights per week as documented from asleep diary)

• Working night shifts more than five nights per month in the last six months

• Consuming 2 or more alcoholic beverages per day regularly (3 days or more per week)

• Any contra-indications to using the study medication, including lungdisease/breathing problems (e.g., chronic obstructive pulmonary disease), use ofstrong or moderate CYP3A inducers (strong - rifampin, carbamazepine, and St. John'sWort) (moderate - bosentan, efavirenz, etravirine, and modafinil), pregnant andbreastfeeding women

• Not using any method of birth control