Importance of Urinary Drug Screening in the Multiple Sleep Latency Test and Maintenance of Wakefulness Test

Abstract

Study Objectives: Multiple sleep latency testing (MSLT) and the maintenance of wakefulness test (MWT) are gold-standard objective tests of daytime sleepiness and alertness; however, there is marked variability in their interpretation and practice. This study aimed to determine the incidence of positive drug screens and their influence on MSLT, MWT, and polysomnographic variables. Methods: All patients attending Eastern Health Sleep Laboratory for MSLT or MWT over a 21-mo period were included in the study. Urinary drug screening for amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, methadone, and opiates was performed following overnight polysomnography (PSG). Demographics and PSG variables were compared. Results: Of 69 studies, MSLT (43) and MWT (26), 16% of patients had positive urinary drug screening (7 MSLT; 4 MWT). Drugs detected included amphetamines, cannabinoids, opiates, and benzodiazepines. No patient self-reported use of these medications prior to testing. No demographic, MSLT or MWT PSG data or overnight PSG data showed any statistical differences between positive and negative drug screen groups. Of seven MSLT patients testing positive for drug use, one met criteria for the diagnosis of narcolepsy and five for idiopathic hypersomnia. On MWT, three of the four drug-positive patients had a history of a motor vehicle accident and two patients were occupational drivers. Conclusions: These findings indicate drug use is present in patients attending for daytime testing of objective sleepiness and wakefulness. These data support routine urinary drug screening in all patients undergoing MSLT or MWT studies to ensure accurate interpretation in the context of illicit and prescription drug use. Keywords: excessive daytime sleepiness, hypersomnia, narcolepsy Citation: Anniss AM, Young A, O'Driscoll DM. Importance of urinary drug screening in the multiple sleep latency test and maintenance of wakefulness test.

Recommended protocols for the Multiple Sleep Latency Test and Maintenance of Wakefulness Test in adults: guidance from the American Academy of Sleep Medicine

“…Consideration should be given to drug screening as part of the MSLT protocol, as several recreational and illicit drugs can affect both sleep and wake/alertness (i.e., barbiturates, benzodiazepines, cannabinoids, cocaine, methadone and opioids). [21][22][23] The available evidence suggests that up to 33% of adult patients undergoing MSLTs have a positive drug screen. Moreover, a significant number of patients (81% in one study), 23 had not reported use of the detected substance.…”

“…In a study by Anniss et al 2016, 6 out of 26 patients (16%) undergoing an MWT had a positive drug screen for either an amphetamine, cannabis, or benzodiazepine. 22 A variety of reasons motivated patients for their unreported drug use. If a drug screen is performed, the results should be clearly documented in the test report.…”

Remitting narcolepsy? Longitudinal observations in a hypocretin-deficient cohort

“…This work has several limitations. In addition to its retrospective design and small number of included NT1 patients, we must acknowledge that we did not perform urinary drug screening during MSLT/MWT and, hence, may have missed underhand consumption of psychostimulants, with the intention to avoid social/work-related restrictions or being banned from driving [36]. Second, although the employed radioimmunoassay kit for hypocretin-1 has a low inter-and intra-assay variability [19,37,38], its accuracy might be less reliable when CSF hypocretin levels are below 60 pg/ml, and the applied CSF hypocretin detection limit of 30 pg/ml might thus appear as too low.…”