Rexford Muza

Sleep stage sequence analysis of sleep onset REM periods in the hypersomnias

Background The Multiple Sleep Latency Test (MSLT) remains an important diagnostic tool in the diagnosis of hypersomnias. However, a positive MSLT may be found in other sleep disorders, such as behaviourally induced inadequate sleep syndrome (BIISS). It has been demonstrated that in sleep onset rapid eye movement (SOREM) periods in BIISS, REM sleep tends to arise from stage 2 sleep (non-REM (NREM) 2), rather than stage 1 sleep (NREM1), as in narcolepsy. Methods We performed sleep stage sequence analysis on 127 patients with nocturnal polysomnography and MSLT, including 25 with narcolepsy with cataplexy (N+C), 41 with narcolepsy without cataplexy (N−C), 21 with idiopathic hypersomnia with long sleep time (IHL), 20 with BIISS and 20 with periodic limb movement disorder (PLMD). 537 naps were recorded, containing 176 SOREM periods. Results All SOREM periods in the IHL, BIISS and PLMD groups arose from NREM2 sleep, 75% of those in N+C arose from NREM1 and in N−C only 52% arose from NREM1. Within the N−C group, those with SOREM periods all arising from stage 1 had a shorter MSL (p=0.02). Conclusions These results suggest that SOREM periods arising from NREM1 have high sensitivity for the diagnosis of narcolepsy and that SOREM periods from NREM1 are a marker of severity, either of sleepiness or REM instability. Sleep stage sequence analysis of SOREM periods may also aid more accurate phenotyping of the hypersomnias and in particular clarify heterogeneity among patients with narcolepsy without cataplexy.

The reality of sexsomnia.

Purpose of review The purpose of this review is to help further the understanding of the clinical profile of patients with sexsomnia and to better understand the spectrum of the clinical manifestations of sexsomnia. We will review the literature from the past decade on the subject and then compare it with our own clinical experience from patients who were retrospectively identified with sexsomnia at a tertiary sleep clinic over a 6-year period. Recent findings The prevalence of sexual behaviours in sleep remains unknown, but it seems to involve predominantly younger male adults who also frequently exhibit other non-rapid eye movement-related parasomnias. Medication-induced cases have been reported and treatment approach of sexsomnia greatly varies. Of 41 individuals with sexsomnia from our centre with a mean age of 32 (37 men), manifestations of sexsomnia were variable; sexual intercourse was most frequently reported overall, but the majority of women carried out masturbation. Violence and aggression were described on 11 occasions. All patients were amnesic of events. 73% had a history of another parasomnia. Summary Sexsomnia is frequently associated with concurrent sleep conditions or drugs initiation. It is a real clinical disorder which should be properly diagnosed and managed.

Catathrenia, a REM predominant disorder of arousal?

OBJECTIVES Catathrenia is an uncommon and poorly understood disorder, characterized by groaning during sleep occurring in tandem with prolonged expiration. Its classification, pathogenesis, and clinical relevance remain debated, substantially due to the limited number of cases reported to date. We report a series of consecutive cases of catathrenia, their clinical and polysomnographic characteristics, and their subsequent management. METHODS Consecutive patients with catathrenia who had undergone full polysomnography in our institution over a 5.5-year period were included. Catathrenia events (CEs) were examined in clusters, which formulated catathrenia periods (CPs). The relationships between CPs, sleep stage distribution, electroencephalogram (EEG) arousals, and other sleep parameters were assessed, along with the clinical presentation and management of catathrenic patients. RESULTS A total of 427 CPs were identified in 38 patients, 81% arising from rapid eye movement (REM) sleep. EEG arousals preceded or coincided with the onset of 84% of CPs, which were of longer duration than those not associated with an arousal (57.3 ± 56.8 vs. 32.2 ± 29.4 s, p < 0.001). Each CE had a characteristic airflow signal, with inspiration preceding a protracted expiration and a brief more rapid exhalation, followed by deep inspiration. Although the majority of patients were referred on the basis of bed partner complaints, 44.7% complained of daytime sleepiness. Continuous positive airway pressure therapy and sleep-consolidating pharmacotherapy led to subjective improvement, but were limited by poor long-term adherence. CONCLUSIONS In the largest series of catathrenia patients reported to date, we found that this rare disorder is characterized by a distinct breathing pattern and arises predominantly from REM sleep, with arousals almost uniformly preceding or coinciding with the onset of CPs.

An Investigation into the Use of Stimulant Therapy during Pregnancy

Introduction. A lack of documentation of stimulant use during pregnancy means that doctors have difficulty advising narcoleptic and hypersomnolent patients. Objectives. To investigate the use of stimulant therapy in narcoleptic and hypersomnolent patients during pregnancy. Method. A search of clinic letters at a tertiary sleep clinic identified women who became pregnant whilst receiving stimulant therapy between 01/09/1999 and 18/11/2010. Fifteen patients were included in a telephone survey. Results. There were 20 pregnancies. The reported advice received with regards to stimulant use was variable. In 7 pregnancies, medication was stopped preconceptually: 1 had a cleft palate and an extra digit 6 had good foetal outcomes. In 8 pregnancies, medication was stopped postconceptually: 1 had autism and attention-deficit hyperactivity disorder; 7 had good foetal outcomes. In 5 pregnancies, medication was continued throughout pregnancy: 2 ended in miscarriage; 1 was ectopic; 2 had good foetal outcomes. The most common symptom experienced was debilitating hypersomnolence. Conclusion. There are no standardised guidelines for use of stimulants during pregnancy. Women have significant symptoms during pregnancy for which there is an unmet clinical need. More research is needed into whether medication can be safely continued during pregnancy, and if not, when it should be discontinued. Better standardized advice should be made available.

The utility of a 5 th nap in multiple sleep latency test

BACKGROUND This is the first study that aimed to look specifically at the utility of the 5(th) nap in the multiple sleep latency test (MSLT), a test used to assist in the diagnosis of narcolepsy. METHODS Data was retrospectively collected from the Sleep Disorders Centre of a Tertiary Hospital on patients that had a 5(th) nap during their MSLT from the 08(th) November 2011 to 12(th) November 2014. RESULTS Fifty-three patients had a 5(th) nap performed out of 378 MSLT studies. In 16% of cases a diagnosis of narcolepsy was given directly due to the inclusion of the 5(th) nap on the MSLT. Here a 5(th) nap allowed diagnostic criteria of mean sleep latency <8 minutes and >2 SOREMPS to be met. In 53% of cases the mean sleep latency increased due to 5(th) nap inclusion; the mean sleep latency of the first four naps was 5.6 vs. 6.7 after inclusion of the 5(th) nap. CONCLUSIONS The 5(th) nap is not often performed within the MSLT studies. Our study shows that only a few patients may benefit from a 5(th) nap opportunity which also led to increase of the mean sleep latency at the expense of extra time, cost, labour and increased patient anxiety.

Catathrenia as a REM predominant disorder of arousal

Catathrenia is an uncommon and poorly understood disorder, characterized by groaning during sleep occurring in tandem with prolonged expiration. Its classification, pathogenesis and clinical relevance remain debated, substantially due to the limited number of cases reported to date. We report a series of consecutive cases of catathrenia, their clinical and PSG characteristics, and their subsequent management. Consecutive patients with catathrenia who had undergone full PSG in our institution over a 5-and-half-year period were included. Catathrenia events (CEs) were examined in clusters, formulating catathrenia periods (CPs). The relationships between CPs, sleep stage distribution, EEG arousals, and other sleep parameters were assessed, along with the clinical presentation and management of catathrenic patients. A total of 427 CPs were identified in 38 patients, 81% arising from REM sleep. EEG arousals preceded or coincided with the onset of 84% of CPs, which were of longer duration than those not associated with an arousal (57.3±56.8 vs 32.2±29.4 sec, p In the largest series of catathrenia patients reported to date, we found that this rare disorder is characterized by a distinct breathing pattern, and arises predominantly from REM sleep, with arousals almost uniformly preceding or coinciding with the onset of catathrenia periods.