0719 Much Ado About Nothing? Cannabinoids Do Not Impact Multiple Sleep Latency Test Variables in Suspected Central Disorders of Hypersomnolence Patients

Abstract Introduction Urine drug testing (UDT) during MSLT is performed to rule out the presence of confounding substances. The 2021 AASM recommendations highlight cannabinoids as particularly relevant to MSLT interpretation, citing reports of shortened sleep latency or, after recent discontinuation, REM rebound. However, conflicting reports exist. Prevalence of cannabinoid use among patients with central disorders of hypersomnolence (CDH) is unknown. Methods Retrospective analysis was performed of patients with suspected CDH undergoing PSG/MSLT at Cleveland Clinic, 3/2009-2/2025, who had immunoassay UDT prior to MSLT. Included patients met ICSD-3 criteria for narcolepsy type 1/2 (NT1/2), idiopathic hypersomnia (IH) or undifferentiated hypersomnia (UH). For analyses involving MSLT parameters, the “cannabinoid positive” group (UDT+) was comprised of patients with UDT positive for cannabinoids alone. Results From 1,031 cases with verified ICSD-3 diagnoses, 91 (8.8%) had UDT positive for cannabinoids. Positivity did not differ between CDH subgroups (6/55 (10.9%) in NT1, 7/98 (7.1%) NT2, 21/258 (8.1%) IH, 57/620 (9.2%) UH; p=0.84). Overall N = 1,019 (54 NT1, 97 NT2, 256 IH, 612 UH) after excluding cases positive for >1 substance. UDT+ and UDT- groups did not differ in age (34.0±11.9 vs 35.0±14.5; p=0.89), female sex (61 (77.2%) vs 686 (73.0%); p=0.49), BMI (26.6[22.7, 31.5] vs 27.2[23.3, 32.3]; p=0.46), or race/ethnicity composition (58 (73.4%) Caucasian vs 734 (78.4%) Caucasian; p=0.49). However, UDT+ had higher Epworth Sleepiness Scale scores (15.2±5.1 vs 14.0±5.2; p=0.025) and lower AHI on PSG (1.00[0.30,3.4] vs 1.8[0.70,5.0]; p=0.011). For MSLT outcomes, UDT+ and UDT- did not differ by total SOREMPs (0.00[0.00,1.00] UDT+ vs 0.00[0.00,1.00] UDT-; p=0.45) or mean sleep latency (MSL) (10.6[5.3,13.5] UDT+ vs 10.0[5.9,14.6] UDT-; p=0.89). Likewise, UDT+ had similar likelihood as UDT- of reaching 2+ SOREMPs (13 (16.5%) UDT+ vs 184 (19.6%) UDT-; p=0.63) or MSL ≤ 8 (30 (30.8%) UDT+ vs 373 (39.7%) UDT-; p=0.75). Conclusion These findings demonstrate that a clinically important percentage of patients with suspected CDH use cannabinoids. Additionally, our results do not support ruling MSLTs as invalid solely due to cannabinoid use. Given the similar prevalence of MSLTs with MSL ≤ 8 and/or 2+ SOREMPs between groups, cannabinoids may not impact classification of CDH subtypes; further research is needed. Support (if any)