Narcolepsy-like pathologic daytime sleepiness in a patient with obsessive-compulsive disorder and attention deficit hyperactivity disorder: a Case Report.

Excessive daytime sleepiness (EDS) is a frequent complaint in the general population. Other than being a common symptom associated with various sleep disorders, EDS may be a consequence of chronic sleep deprivation or the primary symptom of central disorders of hypersomnolence (CDH). In addition to narcolepsy type 1 (NT1), the other conditions within the CDH spectrum are less well-defined and share considerable clinical and neurophysiological similarities. Herein, we describe the clinical management of a complex case that highlights several challenges in the diagnostic process of a patient with EDS and a history of obsessive-compulsive disorder (OCD). In the absence of other sleep disorders, secondary structural causes, and orexin deficiency as possible causes for EDS, the patient was initially diagnosed with NT2 based on electrophysiological criteria. However, the clinical course, which showed only a partial response to various stimulant medications for subjective and objective daytime sleepiness, led us to question the diagnosis. A detailed psychiatric and neuropsychological assessment revealed, in addition to the previously identified severe OCD and anxiety, a diagnosis of attention deficit hyperactivity disorder (ADHD), subsequently leading to a revised diagnosis of hypersomnia associated with a psychiatric disorder (HPSY). The literature regarding OCD and sleep disorders remains scarce but the connection between ADHD and hypersomnia, as well as narcolepsy, is well-established. Our case report illustrates that a psychiatric and neuropsychological assessment should be considered mandatory for patients with objective EDS.