P101 An audit of the clinical impact of mandatory urinary drug screening performed as part of Maintenance of Wakefulness and Multiple Sleep Latency Testing’

Abstract Study Objectives Multiple sleep latency testing (MSLT) and maintenance of wakefulness testing (MWT) are validated objective assessments of excessive daytime sleepiness. However, both are open to the confounding effects of drugs. This study aims to determine the rates of detection of drugs with known effects of sleep architecture using both immunoassay (IA) and mass spectrometry (MS) urinary drug screens (UDS) during MSLT/MWT testing. Methods A retrospective audit was performed on all patients who underwent an MSLT/MWT test at a tertiary hospital sleep laboratory between 2013-2023. Data was collected on the rates of positive IA and MS UDS, disclosure of the drug to their treating physician, demographics, comorbidities, and polysomnographic variables. Results 162 patients were included in the analysis, 137 MSLT patients and 25 MWT patients. 29/162 (17.9%) and 67/162 (51.3%) of patients had a positive IA-UDS and MS-UDS respectively. These drugs were disclosed in 44% of positive IA-UDS and 68% of MS-UDS positive patients. Patients with a positive IA and MS UDS during MSLT were more likely to have an elevated HADS-A questionnaire result and clinically diagnosed anxiety and depression, history of malignancy (IA-UDS) and chronic pain (MS-UDS). There was no correlation between positive UDS results and any variables in patients undergoing MWT. Conclusions There is limited data on the rates of positive UDS routinely performed as part of MSLT/MWT. This has made it difficult to determine the optimal screening method. This study demonstrates that in patients undergoing MSTL/MWT testing, positive IA and MS-UDS are common and frequently not disclosed.