1028 Marijuana Use and the Multiple Sleep Latency Test: A Diagnostic Dilemma

Abstract

Introduction: A standardized Multiple Sleep Latency Test (MSLT) can help determine if a patient who suffers from subjective excessive daytime sleepiness has objective hypersomnolence. Marijuana is the most commonly used illicit drug in the US and recreational use is becoming legal in many states1. MSLT findings can be complicated by marijuana use and cause false positive diagnoses of narcolepsy2. Report of Case: A 43-year-old woman presents to the sleep disorders clinic with excessive daytime sleepiness (EDS), insomnia, sleep disruption, sleep attacks, and cataplexy episodes. MSLT results: Mean sleep latency was severely reduced at 0.5 minute, with a total of 4 sleep-onset REM periods (SOREMPS) occurring during naps 1, 2, 3, and 4. Urine drug screen on the day of the MSLT was positive for marijuana. Conclusion: Marijuana use can cause daytime sleepiness and shorten both REM onset and sleep onset times during the MSLT, causing false positive results. Given the potential for drug abuse in marijuana users, a urine drug screen should always be performed prior to the MSLT in order to mitigate the recreational use of potentially habit-forming medications for narcolepsy. Support/Discussion: There are limited studies evaluating how MSLT results are affected by a positive urine drug screens. Positive screens may confound the diagnosis of idiopathic hypersomnia and narcolepsy without cataplexy as they rely heavily on positive MSLT findings for diagnosis2. Performing a drug screen before an MSLT can significantly alter the diagnosis and management of hypersomnolence. A positive urine drug screen may preclude the need for an MSLT altogether2. Marijuana use is also prevalent in adolescents. In one study, 10% of adolescents with EDS had both a positive drug screen for marijuana and positive MSLT findings3. There are no current guidelines on how to treat patients with concurrent positive drug screens and MSLT findings. Even if a true central hypersomnia is confirmed, treatment options may be limited as most treatments are controlled medications that may not be appropriate for patients with a history of illicit drug use.