Cardiovascular and Cognitive Implications of Central Disorders of Hypersomnolence and Their Treatments

Inclusion Criteria: * Diagnosed with narcolepsy or idiopathic hypersomnia according to International Classification of Sleep Disorders, third edition * Age 18 - 75 years * BMI between 18 and 40 kg/m2 * Prescribed a medication of interest (e.g., sodium oxybate, low sodium oxybate, pitolisant, modafinil/armodafinil, solriamfetol, traditional stimulant(s)) by a clinical sleep specialist as part of routine medical care. * Subject must be willing to postpone starting medication until after completion of baseline assessment(s). * If subject has been taking a prescribed hypersomnia medication(s) at a stable dose for at least 3 months and has been prescribed a new medication, then subject may complete baseline assessment(s) while taking initial hypersomnia medication(s) before starting new medication. Exclusion Criteria: * Any change to medication(s) within the last 45 days * History of chronic alcohol or drug abuse within the prior 12 months * Heart failure, history of severe hypertension, or other cardiovascular disease compromising the patient's wellbeing or ability to participate in this study * Use of any sleep apnea treatment (e.g., Positive Airway Pressure (PAP) therapy, oral appliance therapy, etc.) within 45 days of baseline assessment visit * Participation in another study of an investigational drug within the 28 days prior to screening visit or currently * Pregnancy and/or breast-feeding * Subjects who, in the opinion of the Investigator, may not be suitable for the stu…