Polysomnography and Other Sleep Testing

Multiple methods are available for evaluating sleep concerns: clinical screening instruments, sleep diaries, polysomnography with multiple sleep latency test and maintenance of wakefulness test, and actigraphy. This chapter reviews the tools used to assess patients with sleep concerns. Screening tools such as questionnaires are used to stratify patients on the basis of their clinical characteristics and risk factors for sleep difficulties. Patients at high risk may need urgent polysomnography or further treatment.

P106 Evaluating the correlation between objective daytime sleepiness, daytime functioning and subjective sleepiness

Introduction Daytime sleepiness is typically assessed in clinical settings with the Multiple Sleep Latency Test (MSLT) and Maintenance of Wakefulness Test (MWT). However, these tests do not necessarily assess daytime functioning. This study aimed to assess the correlation between a 10-min Psychomotor Vigilance Test (PVT), as a measure of daytime functioning, and excessive daytime sleepiness as measured with the MSLT or MWT. Methods Patients attending the sleep clinic for assessments of daytime sleepiness underwent overnight polysomnography (PSG) and completed the Epworth Sleepiness Scale (ESS). The following day, patients completed four test sessions every 2h starting 1.5h after waking. Testing sessions included the Stanford Sleepiness Scale (SSS), PVT, MWT or MSLT. PVT lapses (reaction time >500ms), SSS score and sleep latencies (MSLT and MWT) were averaged within participants across sessions and regression analyses performed to assess the relationship between PVT lapses and sleepiness measures. Results A total of 41 patients (BMI: 33.7±8.7kg/m²; aged 44.8±17.8 years) completed the study. Of these, 22 (19 F) underwent the MSLT and 19 (2 F) underwent the MWT. PVT lapses correlated with MWT mean sleep latency (r²=0.62; p<0.001), ESS (r²= 0.19; p<0.01) and SSS (r²= 0.12; p<0.05) but not MSLT mean sleep latency (r²= 0.02; p = 0.50). Discussion In clinical practice, MWT and ESS are often used in conjunction to assess daytime functioning. Results suggest that the PVT could be used alongside MWT to aid clinical judgments around an individuals’ daytime functioning.

P130 An audit of urinary drug screening use in multiple sleep latency and maintenance of wakefulness testing in an Australian tertiary centre

Multiple sleep latency test (MSLT) and maintenance of wakefulness test (MWT) are objective measures of excessive daytime sleepiness, used in diagnosing and monitoring patients with sleep disorders. MSLT and MWT can be affected by substances such as psychotropics, stimulants, opioids and sedatives. Recent studies demonstrate high prevalence of positive urine drug screening (UDS) results in patients undergoing MSLT and MWT. We retrospectively audited patients who underwent UDS with MSLT/MWT at a tertiary centre from 1st January 2019 to 1st January 2020. The following data was collected: MSLT/MWT/UDS results, sleep disorder diagnosis/es, return to driving/work after testing and pre-existing and subsequent prescription of stimulants/wakefulness-promoting agents/psychotropics/sodium oxybate. Our cohort featured 32 patients (23 female). 29 MSLTs and 3 MWTs were performed. Median age was 31 years old. 13 patients were on wakefulness-promoting agents/psychotropics when tested, where 8 were on serotonin–norepinephrine reuptake inhibitors/selective serotonin reuptake inhibitors. 13 patients (~45%) had a reduced mean sleep latency (MSL), where 10 minutes was used as the cut-off. All 3 MWTs were within normal limits. 5 patients (~16%) had a positive UDS. 1 patient had a low MSL and tested positive for cannabinoids and opioids. The other 4 patients with normal MSL tested positive for benzodiazepines (2), cannabinoids (1) and opioids (1). All patients were cleared for work and 85% of patients who had a low MSL returned to work during follow-up. The rate of positive UDS in patients undergoing MSLT/MWT was comparable to existing publications and re-emphasizes the relevance of mandating UDS prior to MSLT/MWT.

Once-Nightly Sodium Oxybate (FT218) Demonstrated Improvement of Symptoms in a Phase 3 Randomized Clinical Trial in Patients With Narcolepsy

Study Objectives To assess the efficacy and safety of FT218, a novel once-nightly formulation of sodium oxybate (ON-SXB), in patients with narcolepsy in the phase 3 REST-ON trial. Methods Narcolepsy patients aged ≥16 years were randomized 1:1 to uptitration of ON-SXB (4.5, 6, 7.5, and 9 g) or placebo. Three coprimary endpoints were change from baseline in mean sleep latency on the Maintenance of Wakefulness test, Clinical Global Impression-Improvement rating, and weekly cataplexy attacks at 9, 7.5, and 6 g. Secondary endpoints included change from baseline on the Epworth Sleepiness Scale. Safety included adverse drug reactions and clinical laboratory assessments. Results In total, 222 patients were randomized; 212 received ≥1 dose of ON-SXB (n=107) or placebo (n=105). For the 3 coprimary endpoints and Epworth Sleepiness Scale, all 3 doses of ON-SXB demonstrated clinically meaningful, statistically significant improvement vs placebo (all P<0.001). For ON-SXB 9 g vs placebo, increase in mean sleep latency was 10.8 vs 4.7 min (LSMD [95% CI], 6.13 [3.52–8.75]), 72.0% vs 31.6% were rated much/very much improved on Clinical Global Impression-Improvement (OR [95% CI], 5.56 [2.76–11.23]), change in mean weekly number of cataplexy attacks was –11.5 vs –4.9 (LSMD [95% CI], –6.65 [–9.32 to –3.98]), and change in Epworth Sleepiness Scale was –6.5 and –2.7 (LSMD [95% CI], –6.52 [–5.47 to –2.26]). Common adverse reactions included nausea, vomiting, headache, dizziness, and enuresis. Conclusions ON-SXB significantly improved narcolepsy symptoms; its safety profile was consistent with SXB. ON-SXB conferred efficacy with a clearly beneficial single nighttime dose.

Ambulatory circadian monitoring in sleep disordered breathing patients and CPAP treatment

Our aim was to evaluate the circadian rhythm of motor activity, body position and integrated variable TAP (composed by wrist Temperature, motor Activity and body Position) in Sleep Disordered Breathing (SDB), its relation to SDB severity and the effect of continuous positive airway pressure (CPAP) on these circadian rhythms. To do this, we monitored motor activity and body position rhythms of 78 SDB patients (53.3 ± 1.2 years old, 26.9% women) and 32 healthy subjects (51.4 ± 3.2 years old, 43.8% women) for 1 week. On the last day of that week, SDB patients underwent a polysomnography followed by a Maintenance of Wakefulness Test, Multiple Sleep Latency Test and Sustained Attention to Response Task protocol. A subgroup of 18 moderate to severe SDB patients was treated with CPAP and monitored again after 3 months under treatment. A non-parametrical analysis was performed to characterize the circadian patterns to assess differences between groups and associations between sleep and circadian parameters. Circadian variables were altered in SDB, exhibiting a direct relationship to SDB severity. The motor activity pattern showed a clear improvement with CPAP treatment. Thus, circadian ambulatory monitoring, including the integrated variable TAP, could be used to evaluate the circadian alterations caused by SDB and activity pattern to monitor the effect of CPAP treatment.

Self-perceived sleep during the Maintenance of Wakefulness Test: how does it predict accidental risk in patients with sleep disorders?

Study Objectives To determine whether the feeling of having slept or not during the Maintenance of Wakefulness Test (MWT) is associated with the occurrence of self-reported sleep-related traffic near misses and accidents in patients with sleep disorders. Methods This study was conducted in patients hospitalized in a French sleep center to perform a 4*40 min MWT. Relationship between mean sleep latency on the MWT, feeling of having slept or not during MWT trials and sleep-related near misses and accidents reported during the past year was analyzed. Results 192 patients suffering from OSAS, idiopathic hypersomnia, narcolepsy, restless leg syndrome or insufficient sleep syndrome were included. 165 patients presented no or one misjudgment of feeling of having slept during MWT trials while 27 presented more than two misjudgments. Almost half of the latter (48.1%) reported a sleepiness-related traffic near miss or accident in the past year versus only one third (27.9%) for the former (P<.05). Multivariate logistic regression showed that patients with more than two misjudgments had a 2.52-fold (95% CI, 1.07–5.95, P<.05) increase in the risk of reporting a sleepiness-related near miss/accident. Conclusions Misjudgment in self-perceived sleep during the MWT is associated with the occurrence of self-reported sleepiness-related traffic near misses and accidents in the past year in patients suffering from sleep disorders. Asking about the perception of the occurrence of sleep during the MWT could be used to improve driving risk assessment in addition to sleep latencies.

489 Pivotal Phase 3 Study of FT218, a Once-Nightly Sodium Oxybate Formulation, in Patients With Narcolepsy: REST-ON Primary Results

Introduction Sodium oxybate (SO) is an effective treatment for patients with narcolepsy; however, currently available SO formulations require twice-nightly dosing. The purpose of this study was to evaluate efficacy and safety of FT218, an investigational once-nightly controlled-release SO formulation, for the treatment of excessive daytime sleepiness and cataplexy in patients with narcolepsy types 1 (NT1) and 2 (NT2). Methods This was a randomized, double-blind, placebo-controlled, multicenter study in patients with narcolepsy ≥16 years old. Patients were randomized 1:1 to receive FT218 or matching placebo: 4.5 g/night for 1 week, 6.0 g/night for 2 weeks, 7.5 g/night for 5 weeks, and 9.0 g/night for 5 weeks (maximum treatment duration, 13 weeks). Coprimary endpoints were mean sleep latency (minutes) on maintenance of wakefulness test (MWT), Clinical Global Impression-Improvement (CGI-I) of sleepiness, and weekly number of cataplexy attacks (NCAs; NT1 only). Results A total of 212 patients were randomized and received study treatment (FT218, n=107; placebo, n=105). FT218 showed significant (P<0.001) improvement vs placebo in mean sleep latency on MWT for all evaluated doses; LS mean difference (minutes) between FT218 and placebo was 6.13 at 9.0 g (week 13), 6.21 at 7.5 g (week 8), and 4.98 at 6.0 g (week 3). A higher proportion of patients receiving FT218 were much/very much improved on CGI-I vs placebo (72% vs 31.6% at 9.0 g; 62.6% vs 22.8% at 7.5 g; and 40.1% vs 6.1% at 6.0 g; all P<0.001). LS mean difference between FT218 and placebo in mean weekly NCAs was significant (P<0.001) for all doses: −6.65 at 9.0 g, −6.27 at 7.5 g, and −4.83 at 6.0 g. The most common adverse reactions were nausea, vomiting, headache, dizziness, enuresis, and decreased appetite. Conclusion All evaluated doses of FT218 showed significant improvement vs placebo in mean sleep latency on MWT, CGI-I, and weekly NCAs. FT218 was generally well tolerated and the most common adverse events were consistent with known side effects of SO. Support (if any) Avadel Pharmaceuticals.

519 Restless Legs and Periodic Limb Movements in 86 patients with Multiple Sclerosis

Introduction The aim of this study was to assess the prevalence of restless legs syndrome (RLS), periodic limb movements during sleep (PLMS) and their overlap in a large population of patients with multiple sclerosis (MS), and to compare clinical and paraclinical findings between patients with and without RLS/PLMS. Methods In this cross–sectional, observational, instrumental study, eighty-six patients (M/F: 27/59; mean age 48.0 ± 10.8 years) with a diagnosis of MS underwent a structured telephone interview assessing the five standard diagnostic criteria for RLS. Seventy-six participants underwent Video-polysomnography and Maintenance of Wakefulness Test (MWT). Instrumental and clinical findings were subsequently statistically compared to investigate their association with RLS and PLMS index (PLMSI). Results RLS and PLMS (PLMSI ≥15/h) prevalence in patients with MS was of 31.4% and 31.6% respectively. Among patients with RLS, 37.5% had a PLMSI ≥15/h. In the group with PLMS, 37.5% met all diagnostic criteria for RLS. No differences were found between patients with and without RLS (F = 0.99, p = 0.45), and between patients with and without a PLMSI ≥15/hour (F = 0.32 p = 0.94) on the pool of clinical and instrumental variables. Conclusion RLS is highly prevalent and severe in patients with MS. The prevalence of PLMS is comparable to the general population. The low percentage of patients with RLS having a high PLMSI, together with the absence of correlation between RLS and female gender and older age, support the existence of a distinct symptomatic form of RLS in MS. Support (if any):