OBJECTIVE AND BACKGROUND:Health-related quality of life (HRQoL) is reduced in narcolepsy type 1 (NT1), but proper information on HRQoL in narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH) is lacking. This study examines HRQoL of NT1, NT2, IH, and healthy controls (HC) and assesses the HRQoL associates in these diseases. PATIENTS AND METHODS:117 adults (64 NT1, 22 NT2, 31 IH; 61.5 % women; 38.3 ± 12.0 years; 71.8 % treated) and 41 HC (53.7 % women; 35.9 ± 9.6 years) completed questionnaires assessing sleepiness, fatigue, symptoms severity, sleep inertia, depressive and anxiety symptoms, HRQoL, and underwent a semi-structured interview. Data were analyzed using the Mann-Whitney and Kruskal-Wallis tests, Spearman's correlation coefficient, and regression analysis. RESULTS:HRQoL of NT1, NT2, and IH, separately, was poorer compared to HC (p < 0.001). According to the 36-Item Short Form Health Survey, the mental HRQoL was more impaired in NT2 and IH than NT1 (p < 0.05) in association with more pronounced depressive symptoms (p < 0.01; p < 0.05, respectively) and sleep inertia (p < 0.01; p < 0.01, respectively). Psychiatric disorders were more prevalent in NT2 and IH versus NT1 (p < 0.05). CONCLUSION:HRQoL is reduced in NT1, NT2, and IH, with this reduction being more pronounced in NT2 and IH. Poor mental HRQoL of NT2 and IH was associated both with the severity of depressive symptoms and more intense sleep inertia.

Type 1 narcolepsy (T1N), an autoimmune disease associated with a disruption of hypocretin/orexin neurons, has conserved genetic effects transcending cultures and ethnicities. We pooled data from 5,339 cases from China, Europe, Korea, Japan, and the United States to conduct the first transethnic genome-wide association study (GWAS) on age of onset. Only one strong GWAS significant effect was observed across all ethnicities, summarized by the presence of human leukocyte antigen (HLA)-DQB1*03:01, and centered around the coding region of this gene. In contrast, HLA-DQB1*06:02-positive heterodimer (DQ0602) dosage did not strongly affect onset, and other known narcolepsy-associated genetic loci had minor effects. The HLA-DQB1*03:01 effect (mean −3.47 y, P = 1.7 × 10 −18 ) showed no heterogeneity across ethnic groups and was independent of common allelic variation at HLA-DQA1 in cis of HLA-DQB1*03:01 (DQA1*03:03; DQA1*05:05; DQA1*06:01). This effect may be due to a peptide being presented by all DQ0301 heterodimers (which are tolerant at the P1 binding position), or it may stem from genetic effects of HLA on T cell receptor genes TCRA and TCRB usage that influence the TCR repertoire. Using bulk and single-cell RNA sequencing data across Chinese and Caucasians, who have distinct patterns of linkage disequilibrium around DQB1*03:01, we found that HLA-DQB1*03:01 alters TCR repertoire at specific positions, most significantly within the CDR2α, CDR2β, and CDR3β loops. These results illustrate the remarkable conservation of genetic effects in narcolepsy across ethnicity. The identification of the disease-causing T cells will be crucial for elucidating how this finding relates to the underlying pathophysiology.

In this study, we investigated the effects of HLA-DQB1*03:01 on the onset age of type-1 narcolepsy. We pooled data from 5,339 cases from China, Europe, Korea, Japan, and the United States to conduct the first transethnic study on age of onset (OA). GWAS was used to detect the associated genes. HLA alleles were imputed by HIBAG. Three datasets (DGN, CHINA, and CAUC) were used for TCR analyses. Chinese patients were found to have an earlier age of onset. Independently of this, only one strong GWAS significant effect was observed, summarized by the presence of DQB1*03:01 and centered around the coding region of this gene. In contrast, DQ0602 dosage did not strongly affect onset, and other known narcolepsy-associated genetic loci had minor effects. The DQB1*03:01 effect (mean -3.47 years, p=1.7 10-18) showed no heterogeneity across ethnic groups and was independent of common allelic variation at DQA1 in cis of DQB1*03:01 (DQA1*03:03; DQA1*0505; DQA1*06:01). This effect may be explained by presentation of peptide(s) across all DQ0301 heterodimers, or, considering genetic effects mapping on TCRA and TCRB, effects on TCR repertoire. Using bulk and single-cell RNA-seq data across two ethnic groups, we found that DQB1*03:01 alters TCR repertoire at specific positions, most significantly within the CDR2A, CDR2B and CDR3B loops. These results illustrate the remarkable conservation of narcolepsy genetic effects across ethnicity and suggest that specific TCRs regulate narcolepsy onset. This result will likely be illuminating of the pathophysiology once T cells causative of the disease have been identified.

We have verified the eligibility of the Idiopathic Hypersomnia Severity Scale (IHSS) as a basic clinical tool for determining the subjective severity of illness in patients with idiopathic hypersomnia (IH) in the Czech Republic. Total of 37 patients with a diagnosis of IH (9 men, 28 women, mean age 40.2 ± 12.8) completed the IHSS scale. At the same time, they were instructed to complete the Epworth Sleepiness Scale (ESS), the Fatigue Severity Scale (FSS), the Hospital Anxiety and Depression Scales (HADS-A and HADS-D), and a short version of the Quality of Life Questionnaire (SF-36). The control group consisted of 88 ageand sex-matched healthy volunteers. The IHSS scale showed good internal consistency of the questionnaire using Cronbach’s α, which was 0.88. The KMO (Keiser-Meyer-Olkin index) was 0.72, confirming sufficient structural validity of the questionnaire. The correlation of the total IHSS score with the ESS (ρ = 0.59, p=0.0001) and FSS (ρ = 0.84, p<0.0001) as well as with the HADS-A scales (ρ = 0.64, p<0.0001), HADS-D (ρ = 0.79, p<0.0001) and SF-36 in both the mental (ρ = –0.85, p<0.0001) and physical health (ρ = –0.66, p<0.0001) components. The IHSS is a convenient and easy-to-apply clinical tool to assess subjective severity of illness, which describes well the symptoms of idiopathic hypersomnia and assesses their impact on health and daily activities.

In recent years, there has been an increased interest in elucidating the influence of the gut microbiota on sleep physiology. The gut microbiota affects the central nervous system by modulating neuronal pathways through the neuroendocrine and immune system, the hypothalamus-pituitary-adrenal axis, and various metabolic pathways. The gut microbiota can also influence circadian rhythms. In this study, we observed the gut microbiota composition of patients suffering from narcolepsy type 1, narcolepsy type 2, and idiopathic hypersomnia. We did not observe any changes in the alpha diversity of the gut microbiota among patient groups and healthy controls. We observed changes in beta diversity in accordance with Jaccard dissimilarities between the control group and groups of patients suffering from narcolepsy type 1 and idiopathic hypersomnia. Our results indicate that both these patient groups differ from controls relative to the presence of rare bacterial taxa. However, after adjustment for various confounding factors such as BMI, age, and gender, there were no statistical differences among the groups. This indicates that the divergence in beta diversity in the narcolepsy type 1 and idiopathic hypersomnia groups did not arise due to sleep disturbances. This study implies that using metabolomics and proteomics approaches to study the role of microbiota in sleep disorders might prove beneficial.

Aim: The aim of the study was to verify the applicability of the Narcolepsy Severity Scale (NSS) as a basic clinical tool for determining the subjective severity of the disease in patients with narcolepsy type 1 (NT1) in the Czech Republic. Patients and methods: A total of 78 patients from 2 sleep centers with a dia gnosis of NT1 (29 men, 49 women, mean age 36.1 +/- 11.7 years, range 18-71 years, N = 51 were treated) completed the NSS scale consisting of 15 questions focusing on the occurrence, frequency, and impact on daily activities of all major narcoleptic symptoms. At the same time, they were instructed to complete the Epworth Sleepiness Scale (ESS), the Fatigue Severity Scale (FSS), the Hospital Anxiety and Depression Rating Scale (HADS) and a short version of the Quality of Life Questionnaire (SF-36). Results: The NSS scale shows good internal consistency of the questionnaire using Cronbach's alpha, which is 0.80 for the whole cohort of NT1 patients, 0.79 for the treated group and 0.82 for the untreated group. The Keiser-Meyer-Olkin index for the entire cohort is 0.73, confirming sufficient structural validity of the questionnaire. There was no significant difference in the NSS scores of treated and untreated patients; however, the correlation of the total NSS score with ESS (p = 0.61; P < 0.0001) and FSS (p = 0.4438; P < 0.0001) was confirmed. Conclusions: The NSS is a convenient and practical clinical tool for determining the subjective severity of the disease, well capturing the main narcoleptic symptoms and assessing their impact on daily activities.

Narcolepsy type 1 (NT1) is caused by a loss of hypocretin/orexin transmission. Risk factors include pandemic 2009 H1N1 influenza A infection and immunization with Pandemrix®. Here, we dissect disease mechanisms and interactions with environmental triggers in a multi-ethnic sample of 6,073 cases and 84,856 controls. We fine-mapped GWAS signals within HLA (DQ0602, DQB1*03:01 and DPB1*04:02) and discovered seven novel associations (CD207, NAB1, IKZF4-ERBB3, CTSC, DENND1B, SIRPG, PRF1). Significant signals at TRA and DQB1*06:02 loci were found in 245 vaccination-related cases, who also shared polygenic risk. T cell receptor associations in NT1 modulated TRAJ*24, TRAJ*28 and TRBV*4-2 chain-usage. Partitioned heritability and immune cell enrichment analyses found genetic signals to be driven by dendritic and helper T cells. Lastly comorbidity analysis using data from FinnGen, suggests shared effects between NT1 and other autoimmune diseases. NT1 genetic variants shape autoimmunity and response to environmental triggers, including influenza A infection and immunization with Pandemrix®.

Prof. Bedrich Roth founded sleep medicine in our country 70 years ago. However, the inter- and multidisciplinary nature of sleep medicine developed several decades later, in the early 1990s, with the cooperation of pulmonologists, neurologists and psychiatrists. This led to the foundation of the Czech Sleep Research and Sleep Medicine Society (short title Czech Sleep Society) in 2001. At present, the Society includes 215 members and plays a leading role in the current practice of sleep medicine in the entire country. Activities include accreditation/certification procedures, educational programs, annual national meetings, the development of guidelines and recommendations for different sleep disorders, promoting research and many other endeavors. The society also collaborates with other medical societies in discussions with state health care authorities and health insurance companies. Health insurance companies cover sleep medicine care by means of a DRG system for hospitalizations, and a point system for outpatient care. The majority of sleep medicine care is centralized, and medications are largely covered (e.g. modafinil and natrium oxybate are available to patients free of charge). Positive airway pressure devices are lent to patients by health insurance companies if treatment criteria for sleep breathing disorders are met and compliance is fulfilled. The absence of acknowledged specialization or sub- specialization in sleep medicine by the Czech Ministry of Health is the main challenge to be overcome.

Little attention has been paid to the long-term development of idiopathic hypersomnia symptoms and idiopathic hypersomnia comorbidities. The aim of this study was to describe the general health of patients with idiopathic hypersomnia years after the initial diagnosis, focusing on current subjective hypersomnolence and the presence of its other possible causes. Adult patients diagnosed with idiopathic hypersomnia ≥ 3 years ago at sleep centres in Prague and Kosice were invited to participate in this study. A total of 60 patients were examined (age 47.3 ± SD = 13.2 years, 66.7% women). In all participants, their hypersomnolence could not be explained by any other cause but idiopathic hypersomnia at the time of diagnosis. The mean duration of follow-up was 9.8 + 8.0 years. Fifty patients (83%) reported persisting hypersomnolence, but only 33 (55%) had no other disease that could also explain the patient's excessive daytime sleepiness and/or prolonged sleep. In two patients (3%), the diagnosis in the meantime had changed to narcolepsy type 2, and 15 patients (25%) had developed a disease or diseases potentially causing hypersomnolence since the initial diagnosis. Complete hypersomnolence resolution without stimulant treatment lasting longer than 6 months was reported by 10 patients (17%). To conclude, in a longer interval from the diagnosis of idiopathic hypersomnia, hypersomnolence may disappear or may theoretically be explained by another newly developed disease, or the diagnosis may be changed to narcolepsy type 2. Thus, after 9.8 years, only 55% of the examined patients with idiopathic hypersomnia had a typical clinical picture of idiopathic hypersomnia without doubts about the cause of the current hypersomnolence.

Study objectives: Microbial antigens can elicit an immune response leading to the production of autoantibodies cross-reacting with autoantigens. Still, their clinical significance in human sera in the context of brain diseases is unclear. Therefore, assessment of natural autoantibodies reacting with their neuropeptides may elucidate the autoimmune etiology of central hypersomnias. The study aims to determine whether serum autoantibody levels differ in patients with different types of central hypersomnias (narcolepsy type 1 and 2, NT1 and NT2; idiopathic hypersomnia, IH) and healthy controls and if the differences could suggest the participation of autoantibodies in disease pathogenesis.Methods: Sera from 91 patients with NT1, 27 with NT2, 46 with IH, and 50 healthy controls were examined for autoantibodies against assorted neuropeptides. Participants were screened using questionnaires related to sleep disorders, quality of life, and mental health conditions. In addition, serum biochemical parameters and biomarkers of microbial penetration through the intestinal wall were determined.Results: A higher prevalence of autoantibodies against neuropeptides was observed only for alpha-melanocytesstimulating hormone (alpha-MSH) and neuropeptide glutamic acid-isoleucine (NEI), which differed slightly among diagnoses. Patients with both types of narcolepsy exhibited signs of microbial translocation through the gut barrier. According to the questionnaires, patients diagnosed with NT2 or IH had subjectively worse life quality than patients with NT1. Patients displayed significantly lower levels of bilirubin and creatinine and slightly higher alkaline phosphatase values than healthy controls.Conclusions: Overall, serum anti-neuronal antibodies prevalence is rare, suggesting that their participation in the pathophysiology of concerned sleep disorders is insignificant. Moreover, their levels vary slightly between diagnoses indicating no major diagnostic significance.

Background: Delayed sleep-wake phase disorder (DSWPD) is a chronic condition with a multifactorial etiology that primarily affects adolescents, significantly influencing their quality of life. In clinical practice, the contribution of intrinsic and behavioral factors is difficult to determine. The aim of our study was to compare data from clinical interviews, sleep diaries, actigraphy, and nocturnal polysomnography (PSG) in a cohort of adolescents with DSWPD and to assess psychiatric/neurodevelopmental comorbidity. Methods: Thirty-one patients (22 male; mean age 15.4 +/- 2.2 years, range 12 to 19 years) with a diagnosis of DSWPD based on detailed history, sleep diary, and actigraphy underwent nocturnal polysomnography (PSG) and neurological, psychological, and psychiatric examination. Results: Attention-deficit/hyperactivity disorder (ADHD) was present in 14 cases (45%), specific learning difficulties in nine (29%), and mood disorder (anxiety/depression) in 16 patients (52%). PSG revealed sleep-onset delay in only 12 (38%) cases. No differences in clinical data or psychiatric comorbidity between the group with sleep delay and the group with normal sleep onset were detected. Decreased total sleep time, sleep efficiency, rapid eye movement (REM) sleep, and prolonged REM sleep latency were observed in patients with delayed sleep onset. Conclusions: PSG showed delayed sleep timing in only 38% of patients with a diagnosis of DSWPD based on diagnostic criteria of the International Classification of Sleep Disorders. We suggest that PSG can provide useful information regarding the prevailing etiology (biological versus behavioral) if dim light melatonin onset testing is not available. (c) 2021 Elsevier Ltd. All rights reserved.

Fatigue, depression, and sleep inertia are frequently underdiagnosed manifestations in narcolepsy and idiopathic hypersomnia. Our cross-sectional study design included diagnostic interview accompanied by assessment instruments and aimed to explore how these factors influence disease severity as well as to elucidate any sex predisposition. One hundred and forty-eight subjects (female 63%) were divided into narcolepsy type 1 (NT1; n = 87, female = 61%), narcolepsy type 2 (NT2; n = 22, female = 59%), and idiopathic hypersomnia (IH; n = 39, female = 69%). All subjects completed a set of questionnaires: Epworth Sleepiness Scale (ESS), Hospital Anxiety and Depression Scales (HADS), Fatigue Severity Scale (FSS), and Sleep Inertia Questionnaire (SIQ). In narcoleptic subjects, questionnaire data were correlated with the Narcolepsy Severity Scale (NSS), and in subjects with idiopathic hypersomnia, with the Idiopathic Hypersomnia Severity Scale (IHSS). The highest correlation in narcoleptic subjects was found between NSS and ESS (r = 0.658; p < 0.0001), as well as FSS (r = 0.506; p < 0.0001), while in subjects with idiopathic hypersomnia, the most prominent positive correlations were found between IHSS and SIQ (r = 0.894; p < 0.0001), FSS (r = 0.812; p < 0.0001), HADS depression scale (r = 0.649; p = 0.0005), and HADS anxiety scale (r = 0.528; p < 0.0001). ESS showed an analogic correlation with disease severity (r = 0.606; p < 0.0001). HADS anxiety and depression scores were higher in females (p < 0.05 and p < 0.01), with similar results for FSS and SIQ scales (p < 0.05 for both), and a trend toward higher ESS values in females (p = 0.057). Our study illustrates that more attention should be focused on pathophysiological mechanisms and associations of fatigue, depression, as well as sleep inertia in these diseases; they influence the course of both illnesses, particularly in women.

Aims of the study:Commonly used approach to illness assessment focuses on the patient's actual state supplemented by binary records of past events and conditions. This research project was designed to explain subjective experience in idiopathic hypersomnia (IH) patients influenced by their clinical symptoms and comorbidities.Material and Methods:Forty-three IH patients of both sexes (female 60.5%, male 39.5%) were assessed using a detailed structured examination. The interview covered neurologic, psychiatric, and internal medicine anamnesis, medication past and current, substance abuse, work impairment, detailed sleep-related data, specific sleep medication, and a full-length set of questionnaires including depression, quality of life, sleepiness, anxiety, fatigue, insomnia, and sleep inertia. The data were digitized and imported into statistical software (SPSS by IBM), and dynamic simulation software (Vensim by Ventana Systems Inc.) was used to build a causal loop diagram and stocks and flows diagram as a simulation structure.Results:The overall raw data and simulation-based patterns fit at 76.1%. The simulation results also identified the parameters that contribute the most to patients' subjective experience. These included sleep inertia, the refreshing potential of naps, the quality of nocturnal sleep, and the social aspects of the patient's life. Psychiatric disorders influence the overall pattern at a surprisingly low level. The influence of medication has been studied in detail. Although its contribution to the dynamics looks marginal at first sight, it significantly influences the contribution of other variables to the overall patient experience of the disease.Conclusion:Even the simplified dynamic structure designed by the research team reflects the real-life events in patients with IH at the acceptable level of 76.1% and suggests that a similar structure plays an important role in the course of the disease. Therapeutic focus on the parameters identified by the model should enhance the patients' subjective experience throughout illness duration and might even turn the progress from negative into positive. Further research is needed to understand the dynamics of idiopathic hypersomnia in greater detail to better understand the causes and design therapeutic approaches to improve patients' quality of life.

Background: There are limited data available on regional differences in the diagnosis and management of narcolepsy. In order to better understand worldwide trends in clinical assessment and management of narcolepsy, a survey of health-care providers was conducted by the World Sleep Society Narcolepsy task force. Methods: A total of 146 surveys that included items on the diagnosis and management of narcolepsy were completed by practitioners representing 37 countries. Results: Most of the participants were from Europe, North America, Oceania, Asia and Latin America. A consistent approach to applying the diagnostic criteria of Narcolepsy was documented with the exception of measurement of CSF hypocretin-1, which has limited availability. While the majority of practitioners (58%) reported not using the test, 1% indicated always evaluating CSF hypocretin-1 levels. There was much variability in the availability of currently recommended medications such as sodium oxybate and pitolisant; modafinil and antidepressants were the most commonly used medications. Amphetamines were unavailable in some countries. Conclusion: The results of the study highlight clinical and therapeutic realities confronted by worldwide physicians in the management of narcolepsy. While the diagnostic criteria of narcolepsy rely in part on the quantification of CSF hypocretin-1, few physicians reported having incorporated this test into their routine assessment of the condition. Regional differences in the management of narcolepsy appeared to be related to geographic availability and expense of the therapeutic agents. (C) 2021 Elsevier B.V. All rights reserved.

Significance Genetic markers in TRANK1 gene and its vicinity have been weakly associated with bipolar disorder and schizophrenia (10% increased risk). We found that the same polymorphisms are associated with Kleine-Levin syndrome (50% increased risk), a rare sleep disorder characterized by recurrent episodes of severe hypersomnia and cognitive abnormalities. Response to lithium treatment is suggestive of a pathophysiological overlap between KLS and bipolar disorder. The study also shows that variants in the TRANK1 gene region may predispose to KLS when patients have had a difficult birth, suggesting that TRANK1 gene region modulates newborns’ response to brain injury, with consequences for mental and neurological health in adulthood. Another possibility may be that the polymorphism impacts birth and KLS.

Introduction: Idiopathic hypersomnia (IH) is a rare orphan disease characterized by excessive daytime sleepiness, frequently accompanied by prolonged nocturnal sleep and difficulties awakening, termed sleep inertia or sleep drunkenness. Severe sleepiness usually causes a greater handicap than manifestations of narcolepsy. Methods: Forty-three IH patients (17 male, mean age 42.8 +/- SD 12.2 years, range 20-67), diagnosed in the past 20 years according to ICSD-2 or ICSD-3 criteria were invited for clinical examination to evaluate the course, manifestations and severity of the disease, as well as clinical comorbidities. The patients completed a set of questionnaires scoring sleepiness, sleep inertia, fatigue, depression, anxiety, circadian preference, and quality of life. Results: IH patients were divided according to the duration of nocturnal sleep at the time of their diagnosis into two cohorts: (1) with normal sleep duration (n = 25, 58.1%) and (2) with long sleep duration (n = 18, 41.9%). The mean duration of ad libitum sleep per 22 h in the second cohort was 732.0 +/- 115.4 min (range 603e1100), and women markedly prevailed (n = 14, 77.8%). Age at disease onset was younger in the group with long sleep duration (21.2 +/- 11.4 years versus 28.1 +/- 13.6 years, p = 0.028), their MSLT latency was longer (7.2 +/- 3.7 min versus 5.1 +/- 1.7 min, p = 0.005), a history of sleep inertia prevailed (p = 0.005), and daily naps were mostly non-refreshing (p = 0.014). Additionally, questionnaires in the group with long sleep duration showed more severe sleep inertia (p = 0.007), fatigue (p = 0.004), and a tendency towards evening chronotype (p = 0.001). Conclusions: IH patients with long sleep duration differ clinically as well as by objective measures at the time of diagnosis and in long-term follow up from IH patients without long 24-h sleep time. In our opinion they represent an independent clinical entity to be considered in the revised ICSD-3 criteria. (C) 2021 Elsevier B.V. All rights reserved.