0721 The Truth Will Set You Free: Disclosure of Cannabinoid Use by Patient Demographics during Evaluation for Central Disorders of Hypersomnolence

Abstract Introduction The 2021 AASM MSLT protocol recommendations do not provide a uniform requirement for urine drug testing (UDT) in patients undergoing evaluation for central disorders of hypersomnolence (CDH). Rather, UDT may be indicated “depending on clinical and community circumstances.” Selective performance of UDT may result in under-detection of recreational substances, including cannabinoids. Methods Retrospective analysis was performed of patients with suspected CDH undergoing PSG/MSLT at Cleveland Clinic from 3/2009 to 2/2025 who had immunoassay UDT the morning of MSLT. Included patients met ICSD-3 criteria for narcolepsy type 1/2 (NT1/2), idiopathic hypersomnia (IH) or undifferentiated hypersomnia (UH). Disclosure of cannabinoid use was determined by pre-test sleep provider office visit, during which patients were specifically asked about substance use, and from questionnaire responses about recreational drug use. Results Of 1,031 cases with verified ICSD-3 diagnoses (55 NT1, 98 NT2, 258 IH, 620 UH), 85 (8.24%) tested positive for cannabinoids and had documented disclosure data (63 (74.1%) Caucasian, 66 (77.6%) female, age 34.5 ± 11.8). Only 42 patients (49.4%) disclosed cannabinoid use. Differences in age and sex between disclosure and non-disclosure groups were not significant (age 32.7±9.6 vs. 36.2±13.5, p=0.16; female 31 (73.8%) vs. 35 (81.4%), p=0.40, respectively). Race/ethnicity composition was also similar between groups; disclosure group had 33 (78.6%) Caucasian, 7 (16.7%) Black, and 2 (4.8%) Multiracial patients vs. 30 (69.8%) Caucasian, 7 (16.3%) Black, and 6 (14.0%) Multiracial in non-disclosure group (p=0.39). Disclosure across CDH subtypes included 5/6 (83.3%) patients with NT1, 3/6 (50.0%) with NT2, 9/20 (45.0%) with IH, and 25/53 (47.2%) with UH (p = 0.48). Conclusion Among patients with suspected CDH testing cannabinoid-positive on UDT the day of MSLT, nearly half did not disclose their substance use beforehand. Moreover, age, sex, race/ethnicity, and ICSD-3 diagnosis did not correlate with disclosure status. These results suggest that UDT should be universally performed during MSLT, as neither patient report nor demographic factors accurately predict cannabinoid use. Support (if any)