Sleep disturbances are common in patients with autoimmune encephalitis.

OBJECTIVES: Autoimmune encephalitis (AE) is increasingly recognized as an important cause of subacute cognitive decline, seizures, and encephalopathy, with an ever-broadening clinical phenotype. Sleep disturbances are reported in AE patients, including rapid eye movement sleep behavior disorder, hypersomnia, fragmented sleep, and sleep-disordered breathing; however, the prevalence of sleep disturbances and contributions to outcomes in AE patients remain unknown. There is a need to determine the prevalence of sleep disturbances in AE patients, and to clarify the relationship between specific autoantibodies and disruptions in sleep. METHODS: Clinical history, results of serum and cerebrospinal fluid testing, electroencephalography, and neuroimaging were reviewed from 26 AE patients diagnosed and managed at our tertiary care hospital. Polysomnography was performed in patients with clinical indications, yielding data from 12 patients. RESULTS: The median age of AE patients was 53 years (range 18-83). Autoantibodies against intracellular antigens (including Ma and Hu autoantibodies) were identified in 6/26 (23%) patients, while autoantibodies against cell-surface neuronal antigens (including NMDAR and LGI1) were identified in 20/26 (77%) patients. New sleep complaints were reported by 19/26 (73%) AE patients, including gasping or snoring (9/19, 47%), dream enactment behavior (6/19, 32%), insomnia (5/19, 29%), hypersomnia (4/19, 21%), other parasomnias (4/19, 21%), and dream-wake confusional states (2/19, 11%). Dream enactment behaviors were particularly common in AE associated with LGI1 autoantibodies, reported in 4/7 (57%) patients. Polysomnography showed reduced total sleep time, stage 3 and rapid eye movement sleep, and prominent sleep fragmentation. CONCLUSION: Sleep disturbances are common in AE, warranting active surveillance in affected patients. Improved identification and treatment of sleep disorders may reduce morbidity associated with AE and improve long-term outcomes.

Sleep Pathology in Creutzfeldt-Jakob Disease.

STUDY OBJECTIVES: Associations between sleep and neurodegenerative diseases have become increasingly evident. This study aims to characterize the prevalence and type of sleep pathology in Creutzfeldt-Jakob disease (CJD), a rapidly progressive, fatal neurodegenerative disease. METHODS: In this observational cross-sectional cohort study, we performed a retrospective analysis of sleep signs and symptoms in a consecutive group of patients with definite CJD at a tertiary care medical center (n = 28). Polysomnography was performed in 14 patients. RESULTS: Although only 5 of 28 patients carried a premorbid sleep diagnosis, signs/symptoms of sleep pathology were present in 25 patients. Eleven reported hypersomnia whereas 13 reported insomnia. Seven had restless legs symptoms and/or periodic limb movements of sleep, and nine reported parasomnias. Of the 14 patients who underwent polysomnography, 1 did not show sleep, 9 (69%) had poorly formed or absent sleep spindles and/or K-complexes, and 10 (77%) had sleep-disordered breathing. Of the 8 patients who experienced rapid eye movement (REM) sleep during the polysomnography, 3 (38%) showed REM sleep without atonia, and 2 patients met criteria for REM sleep behavior disorder. Median total sleep time was 226 (interquartile range [IQR] = 195-282) min. Median sleep efficiency was 58.5% (IQR = 41-65.5 %). Median REM time was 0.35% (IQR = 0-7.125%). Five patients (38%) demonstrated periodic limb movements during polysomnography. One case is presented. CONCLUSIONS: Sleep pathology is common in CJD, and screening for sleep pathology is indicated in the evaluation of patients with rapidly progressive dementias. Early identification and treatment of sleep pathology may provide an intervenable target for CJD.

The effect of venlafaxine on behaviour, body weight and striatal monoamine levels on sleep-deprived female rats.

Partial sleep deprivation is clinically associated with fatigue, depressive symptoms and reduced memory. Previously, it has been demonstrated that venlafaxine, an atypical antidepressant, increases the levels of noradrenaline and serotonin in rat hippocampus. The aim of this study was to evaluate the effects of venlafaxine on depression, anxiety, locomotor activity and memory in a model of REM sleep (REMs) deprivation in rats. We have also studied the influence of venlafaxine on monoamine levels in the striatum. Six groups of animals (N=20 each) were treated with saline or venlafaxine (1 or 10 mg/kg) during 10 days, submitted or not to REMs deprivation and studied with the forced swimming test of Porsolt (STP), plus-maze, passive avoidance and open-field tests right after sleep deprivation. Animals were also studied for passive avoidance 24 h later (rebound period). Brain samples for monoamine measurements were collected either immediately after REMs deprivation or after 24 h. Both REMs deprivation and venlafaxine showed an antidepressant effect. An anxiolytic effect was also observed after REMs deprivation. Previous treatment with venlafaxine blocked the antidepressant and anxiolytic effects of REMs deprivation. REMs deprivation alone and treatment with venlafaxine 10 mg/kg increased locomotor activity, and this effect was inhibited by venlafaxine in REMs deprived rats. Both venlafaxine treatment and REMs deprivation induced weight loss. Venlafaxine treatment, but not REMs deprivation, induced an increase in striatal dopamine (DA) levels. The combination of REMs deprivation and venlafaxine treatment was associated with an increase in serotonin turnover 24 h after rebound sleep. In this study, venlafaxine treatment hindered most behavioral effects of REMs deprivation and was associated with an interference on dopamine and serotonin systems in the striatum.