Health-related quality of life in narcolepsy

Development of a Mindfulness-Based Intervention for Narcolepsy: A Feasibility Study

STUDY OBJECTIVES

Mindfulness-based interventions (MBI) have been shown to improve psychosocial functioning in medical populations but have not been studied in narcolepsy. This study examined the feasibility and acceptability of an MBI that was adapted for narcolepsy, including three variations in program length.

METHODS

Adults with narcolepsy (N = 60) were randomized to MBI groups of varying durations: brief (4 weeks), standard (8 weeks), or extended (12 weeks). Participants completed assessments at baseline, 4 weeks, 8 weeks, and 12 weeks. To assess feasibility and acceptability, primary outcomes included attendance, meditation practice, and data completeness. Additionally, participants completed measures of mindfulness, self-compassion, mood, sleep, psychosocial functioning, and cognition. An effect size of Cohen's d ≥ 0.5 was used as the pre-specified benchmark for a minimal clinically important difference (MCID).

RESULTS

The attendance, meditation, and data completeness benchmarks were met by 71.7%, 61.7%, and 78.3% of participants, respectively. Higher proportions of the brief and extended groups met these benchmarks compared to the standard group. All groups met the MCID for mindfulness, self-compassion, self-efficacy for managing emotions, positive psychosocial impact, global mental health, and fatigue. Standard and extended groups met the MCID for anxiety and depression, and extended group met the MCID for additional measures including social and cognitive functioning, daytime sleepiness, hypersomnia symptoms, and hypersomnia-related functioning.

CONCLUSION

Results suggest that the remote delivery and data collection methods are feasible to employ in future clinical trials, and it appears that the extended MBI provides the most favorable clinical impact while maintaining attendance and engagement in meditation practice.

The Impact of Symptom Severity on Health-Related Quality of Life in People with Narcolepsy Type 1

OBJECTIVE

To assess the impact of symptom severity on health-related quality of life (HRQoL) in people with narcolepsy type 1 (NT1).

METHODS

A total of 174 people with NT1 were enrolled. They completed the Narcolepsy Severity Scale (NSS) and EQ-5D-3L consisting of five dimensions (EQ-5D utility values) and a visual analog scale (EQ-5D VAS). The relationship between severity of symptoms and HRQoL dimensions was evaluated by Pearson correlation analyses. Logistic regression was used to identify significant predictors of HRQoL. Nomogram was established based on results of independent predictors of factors on logistic regression analyses.

RESULTS

The mean score for NSS, EQ-5D utility values, and EQ-5D VAS were 29.8 (10.08), 0.78 (0.09), and 64.30 (19.84) in people with NT1, respectively. NSS score showed a significant correlation with self-care (r = 0.157, p < .05), usual activities (r = 0.236, p < .01), pain/discomfort (r = 0.174, p < .05), anxiety/depression (r = 0.2, p < .01), and EQ-5D utility values (r = -.261, p < .01). EDS (excessive daytime sleep), cataplexy, hallucinations, paralysis, and disrupted nocturnal sleep (DNS) were significantly associated to EQ-5D VAS (r ranged from -0.154 to -0.354, p < .05). EDS (OR = -0.297) and DNS (OR = -0.16) were predictors of HRQoL. NSS score (OR = -0.360) and treatment (OR = 0.215) were predictors of the metrics of HRQoL. The C-indices of the nomogram were 0.726.

CONCLUSION

The severity of symptoms could disrupt self-care and usual activities, and increase pain/discomfort and anxiety/depression. HRQoL might be improved by alleviating symptom severity.

Sleeping through a pandemic: impact of COVID-19-related restrictions on narcolepsy and idiopathic hypersomnia

STUDY OBJECTIVES

To assess the impact of coronavirus disease 2019 (COVID-19)-related restrictions on narcolepsy type 1 (NT2), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH).

METHODS

Participants with NT1, NT2, and IH followed in a university hospital completed an online 78-question survey assessing demographic, clinical, and occupational features of the population during the first COVID-19-related lockdown.

RESULTS

A total of 219 of 851 (25.7%) respondents of the survey reported a mean increase of 1.2 ± 1.9 hours (P < .001) in night sleep time and a mean decrease of 1.0 ± 3.4 points (P < .001) on the Epworth Sleepiness Scale during lockdown. Bedtime was delayed by 46.1% of participants and wakeup time was delayed by 59.6%, driven primarily by participants with IH. Teleworkers (but not in-person workers) reported a mean increase of 0.9 ± 1.2 hours in night sleep (P < .001) and a mean decrease in sleepiness score of 1.6 ± 3.1 (P < .001). Cataplexy improved in 54.1% of participants with NT1. Sleepiness correlated with psychological wellness (r = .3, P < .001). As many as 42.5% enjoyed the lockdown, thanks to reallocation of time usually spent commuting toward longer sleep time, hobbies, and family time, and appreciated a freer napping schedule. Conversely, 13.2% disliked the lockdown, feeling isolation and psychological distress.

CONCLUSIONS

Extended sleep time, circadian delay (in patients with IH), and teleworking resulted in decreased symptoms of central hypersomnias. These findings suggest that people with IH, NT1, and NT2 may benefit from a decrease in social and professional constraints on sleep-wake habits, and support advocacy efforts aimed at facilitating workplace and schedule accommodations for this population.

CITATION

Nigam M, Hippolyte A, Dodet P, et al. Sleeping through a pandemic: impact of COVID-19-related restrictions on narcolepsy and idiopathic hypersomnia. J Clin Sleep Med. 2022;18(1):255-263.

Health-related quality of life in narcolepsy: A systematic review and meta-analysis

To date, there has been no systematic analysis of the literature regarding health-related quality of life in narcolepsy. This systematic review aimed to examine the impact of narcolepsy on health-related quality of life, measured through standardised health-related quality of life questionnaires such as the Short Form 36 and Functional Outcome of Sleep Questionnaire. The following databases: Medline, Embase, Cinahl, and Web of Science were searched for studies that investigated health-related quality of life in adults with narcolepsy. Studies were reviewed independently by two reviewers, and a random-effects meta-analysis was performed. A total of 30 studies were eligible for inclusion in the review. Additionally, meta-analyses were conducted for the Short Form 36 and the EQ5D. The Short Form 36 meta-analysis identified that the pooled mean scores for the Physical Component Summary (45.91) were less affected than the Mental Component Summary (42.98). People with narcolepsy experience substantially lower health-related quality of life when compared with the general population norms of the USA, UK, France and Norway, as well as compared with people with chronic diseases such as multiple sclerosis, diabetes, hypertension and epilepsy. Further research is warranted to identify the longitudinal effects of narcolepsy on health-related quality of life, and to develop a narcolepsy-specific health-related quality of life tool.

Quality of life and procrastination in post-H1N1 narcolepsy, sporadic narcolepsy and idiopathic hypersomnia, a Swedish cross-sectional study

OBJECTIVE/BACKGROUND

A cross-sectional study of health-related quality of life (HRQoL), procrastination and the relation to sleepiness, depression and fatigue in post-H1N1 narcolepsy type 1 (NT1), sporadic NT1 and idiopathic hypersomnia (IH).

PATIENTS/METHODS

Participants with NT1 and IH were enrolled from the Department of Neurology, Sahlgrenska University Hospital in Gothenburg (Sweden). All participants completed questionnaires about medication, employment, studies, transfer income, sleepiness, HRQoL, depression, fatigue and three questionnaires for procrastination.

RESULTS

Post-H1N1, sporadic NT1 and IH all scored higher than healthy controls on Epworth Sleepiness Scale (ESS), Patient Health Questionnaire (PHQ-9) and Fatigue Severity Scale (FSS), whereas EQ-5D-5L index and VAS was lower than for healthy individuals, but with no difference between groups. Post-H1N1 NT1 had a larger proportion of participants prescribed with sodium oxybate (44% vs. 9%, p = 0.003) and dexamphetamine (62% vs. 17%, p = 0.03) compared to sporadic NT1. The latter also in significantly higher doses than in sporadic NT1 (46 ± 12 vs. 25 ± 10 and 47.5 ± 21 mg, p < 0.0001). Post-H1N1 NT1 also had significantly higher scores on Pure Procrastination Scale (PPS), Irrational Procrastination Scale (IPS) and Susceptibility to Temptation Scale (STS), indicating a higher degree of procrastination. Multivariate analysis showed that depression, and to some extent fatigue, were predictors in NT1 for both HRQoL and procrastination.

CONCLUSIONS

The results show that health-related quality of life is impaired and tendency to procrastinate is higher in patients suffering from NT1 and both attributes can in part be explained by depressive symptoms. These findings highlight the impact of symptoms other than sleep and wakefulness regulation in patients with NT1.

Living with Narcolepsy: Current Management Strategies, Future Prospects, and Overlooked Real-Life Concerns

Narcolepsy is a neurological disorder of the sleep-wake cycle characterized by excessive daytime sleepiness (EDS), cataplexy, nighttime sleep disturbances, and REM-sleep-related phenomena (sleep paralysis, hallucinations) that intrude into wakefulness. Dysfunction of the hypocretin/orexin system has been implicated as the underlying cause of narcolepsy with cataplexy. In most people with narcolepsy, symptom onset occurs between the ages of 10 and 35 years, but because the disorder is underrecognized and testing is complex, delays in diagnosis and treatment are common. Narcolepsy is treated with a combination of lifestyle modifications and medications that promote wakefulness and suppress cataplexy. Treatments are often effective in improving daytime functioning for individuals with narcolepsy, but side effects and/or lack of efficacy can result in suboptimal management of symptoms and, in many cases, significant residual impairment. Additionally, the psychosocial ramifications of narcolepsy are often neglected. Recently two new pharmacologic treatment options, solriamfetol and pitolisant, have been approved for adults, and the indication for sodium oxybate in narcolepsy has been expanded to include children. In recent years, there has been an uptick in patient-centered research, and promising new diagnostic and therapeutic options are in development. This paper summarizes current and prospective pharmacological therapies for treating both EDS and cataplexy, discusses concerns specific to children and reproductive-age women with narcolepsy, and reviews the negative impact of health-related stigma and efforts to address narcolepsy stigma.

Health-related quality of life in patients with narcolepsy types 1 and 2 from a Sleep Center in Brazil

INTRODUCTION

Narcolepsy patients have higher prevalence of comorbidities, such as obesity, depression, and pain. Narcolepsy symptoms and concomitant medical conditions can impact the daily activities of patients. The objective of this study is to describe the quality of life in a sample of patients with narcolepsy, and the influence of the nutritional status in health domains.

METHODS

At Unifesp, two groups of 33 patients (narcolepsy types 1 and 2 meeting 2014 criteria, concerning hypocretin-1) and 33 controls without sleepiness, matched by age and sex, filled out the SF-36.

RESULTS

Narcolepsy groups, regardless of their nutritional status, had significantly lower scores in all domains, compared to controls, mainly in Role-physical, Role-emotional, and Energy/Fatigue. Role-physical score was lower in type 1 than in type 2 and controls (37.8±1.0 vs. 50.0±1.2 vs. 85.6±1.6; p<0.0001). Obese with type 2 narcolepsy scored lower than type 1 in physical scales.

CONCLUSION

In a Sleep Center in São Paulo, Brazil, physical and mental health were impaired in narcolepsy types 1 and 2. The first report of the poor health status in Brazilians with narcolepsy type 2 suggests that obesity negatively affects physical domains.

Health-Related Quality of Life in Patients With Narcolepsy: A Review of the Literature

Narcolepsy is a chronic disorder characterized by symptoms of excessive daytime sleepiness, irresistible sleep attacks that may be accompanied by cataplexy brought on by emotions, sleep paralysis, and hypnagogic hallucinations. This is a review of 32 empirical articles on health-related quality of life (HRQoL) published in peer-reviewed journals over the past 37 years. Deleterious implications on education, recreation, driving, sexual life, and personality are associated with the disease with a consequent negative psychosocial impact. Sleepiness has an important influence on HRQoL, more than the other symptoms of this disorder that have disrupting roles, too. Therefore, patients with narcolepsy need assistance not only for medication prescription but also in terms of psychological and social support. It is also of importance to assess patients with narcolepsy carefully in terms of depressive symptoms because they may have a major impact on HRQoL with important clinical implications.

Correlation of Changes in Patient-Reported Quality of Life With Physician-Rated Global Impression of Change in Patients With Narcolepsy Participating in a Clinical Trial of Sodium Oxybate: A Post Hoc Analysis

INTRODUCTION

Narcolepsy patients report lower health-related quality of life (HRQoL) than the general population, as measured by the Short Form-36 Health Survey (SF-36). This analysis evaluated whether changes in SF-36 correlated with physician-rated Clinical Global Impression of Change (CGI-C).

METHODS

Data were from 209 of 228 narcolepsy patients participating in an 8-week clinical trial of sodium oxybate. Changes from baseline for SF-36 subscales (Physical Functioning, Role Physical, Bodily Pain, General Health, Vitality, Social Functioning, Role Emotional, and Mental Health) and the summary scores were evaluated for correlation with CGI-C overall and by treatment group. Correlations were calculated using the Pearson product-moment correlation coefficient (r).

RESULTS

Correlations described an inverse relationship in scores, but a direct relationship in improvement; lower CGI-C scores (i.e., better) were associated with higher SF-36 subscale scores (i.e., improved HRQoL). Moderate and significant correlations were observed for Vitality (r = -0.464; P < 0.0001) and Role Physical (r = -0.310; P < 0.0001) subscales, but weak correlations were observed with other subscales including summary scores. Correlations were stronger at higher sodium oxybate doses for most SF-36 subscales.

CONCLUSION

Some aspects of HRQoL, measured by the SF-36, may be associated with narcolepsy. In particular, Vitality (indicative of energy and tiredness) and Role Physical (impact of physical function on daily roles) moderately correlated with overall change in status observed by clinicians. However, lack of strong correlations between SF-36 and CGI-C indicates differences in patient and clinician perspectives of disease, and suggest a need for broader assessment of the impact of narcolepsy and its treatment on patients.

FUNDING

Jazz Pharmaceuticals.

The development of a health-related quality-of-life instrument for young people with narcolepsy: NARQoL-21

BACKGROUND

Narcolepsy is a lifelong sleep disorder with a prevalence of between 0.03% and 0.06% and onset at around puberty. It is associated with psychiatric comorbidities and cognitive difficulties. No valid and reliable condition-specific health-related quality-of-life (HrQoL) instrument has been developed for this population.

METHODS

A questionnaire based on four mixed-gender age-defined focus group discussions and a patient panel analysis was administered to young people with narcolepsy and a control group. External reliability was measured by a test-retest procedure and internal reliability was measured using Cronbach's alpha. Convergent validity with the KIDSCREEN-10 index was assessed using with intraclass correlation coefficients (ICC) and receiver operating characteristic (ROC) curves. Factor analysis techniques were used to identify suitable items and confirm the factor structure. Baseline values were assessed for convergent validity, ceiling effects, agreement and sensitivity. Comparison with KIDSCREEN-10 was made on the basis of area under the curve (AUC).

RESULTS

One hundred young people with narcolepsy and 95 control subjects returned questionnaires. The factor structure revealed two main factors with five domains and 21 questions, which was confirmed with confirmatory factor analysis. The domains of the NARQoL-21 showed good independence while the floor and ceiling effects were acceptable. The external reliability (0.928), convergent validity (rs = 0.769) and internal consistency (Cronbach's alpha = 0.886) were excellent. A Bland-Altman plot revealed some proportional bias. Good discriminant validity was detected for control/patient (Cohen's d = 2.114). ROC analysis showed significantly better AUC for NARQoL-21 (0.939) than KIDSCREEN (0.877). A cut-off score equivalent to KIDSCREEN-10 for suboptimal HrQoL which maximized sensitivity (84%) and specificity (92%) was found at NARQoL-21 score below 42.

CONCLUSIONS

Establishing the validity of a disease-specific HrQoL instrument in a population of people with a rare condition poses significant challenges. The mixed-methods approach adopted here has resulted in a questionnaire of 21 items with good discrimination and convergent validity, and excellent internal and external reliability, allowing precise and stable measurements. The cut-off score can be useful to identify patients with very poor HrQoL and thus improve the design of treatment options. Further testing in a longitudinal cohort is recommended in order to establish responsiveness.

Managing Sleep Disorders during Pregnancy

Sleep disturbances and disorders are common during pregnancy, and they can be risk factors for a number of serious pregnancy-related sleep disorders. These include postpartum depression, pregnancy-induced hypertension, gestational diabetes, and intrauterine growth retardation. In addition, certain chronic sleep disorders, such as narcolepsy, are quite challenging to manage in the context of pregnancy and during lactation, particularly with medications that can be teratogenic. This review discusses 4 common sleep disorders and their impacts on pregnancy, and suggests ways to deal with these disorders that improves maternal and fetal outcomes safely. The review discusses diagnosis and treatment of obstructive sleep apnea, restless legs syndrome, insomnia, and narcolepsy in pregnancy.

The Humanistic and Economic Burden of Narcolepsy

STUDY OBJECTIVES

To evaluate the burden of narcolepsy--with respect to psychiatric comorbidities, Health-Related Quality of Life (HRQoL), direct costs for healthcare resource utilization, and indirect costs for reported work loss-through comparison of patients to matched controls.

METHODS

This analysis was conducted on data from the 2011, 2012, and 2013 US National Health and Wellness Survey (NHWS; 2011 NHWS n = 75,000, 2012 NHWS n = 71,157, and 2013 NHWS n = 75,000). Patients who reported a narcolepsy diagnosis (n = 437) were matched 1:2 with controls (n = 874) on age, sex, race/ethnicity, marital status, education, household income, body mass index, smoking status, alcohol use, exercise, and physical comorbidity. Chi-square tests and one-way analyses of variance were used to assess whether the narcolepsy and control groups differed on psychiatric comorbidities, HRQoL, labor force participation, work productivity, and healthcare resource utilization.

RESULTS

Patients with narcolepsy, in comparison to matched controls, reported substantially (two to four times) greater psychiatric comorbidity, HRQoL impairment, prevalence of long-term disability, absenteeism, and presenteeism, and greater resource use in the past 6 mo as indicated by higher mean number of hospitalizations, emergency department visits, traditional healthcare professional visits, neurologist visits, and psychiatrist visits (each p < 0.05).

CONCLUSIONS

These population-based data suggest that a narcolepsy diagnosis is associated with substantial adverse impact on mental health, HRQoL, and key economic burdens that include work impairment, resource use, and both direct and indirect costs. Although this study is cross-sectional, the results highlight the magnitude of the potential opportunity to improve mental health, lower costs, and augment work-related productivity through effective assessment and treatment of narcolepsy.

Evaluation of Quality of Life in Patients With Narcolepsy Treated With Sodium Oxybate: Use of the 36-Item Short-Form Health Survey in a Clinical Trial

Introduction

The present post hoc analysis was designed to evaluate health-related quality of life (HRQoL) using the 36-item Short Form Health Status Survey (SF-36) during an 8-week trial of sodium oxybate (SXB).

Methods

SF-36 was assessed in a phase 3 placebo-controlled trial in patients with narcolepsy (N = 228) randomized to placebo or SXB in doses of 4.5, 6, or 9 g nightly for 8 weeks. Changes from baseline in SF-36 (last observation carried forward) were compared between SXB and placebo, and effect sizes (ES) were estimated.

Results

Baseline SF-36 values were lower than normative values for the US general population. After 8 weeks of treatment, mean (±standard deviation) improvement from baseline on the Physical Component Summary (PCS) was significantly greater with SXB 9 g/night than placebo (6.3 ± 9.1 vs. 1.5 ± 6.2; p = 0.005), with moderate ES; no significant difference was found between the SXB and placebo groups on the Mental Component Summary. SXB 9 g/night resulted in significantly (p < 0.05) greater improvements than placebo in Physical Functioning (4.4 ± 9.2 vs. 1.0 ± 8.0), General Health (GH; 3.1 ± 7.0 vs. 0.4 ± 6.8), and Social Functioning (6.8 ± 16.8 vs. 1.1 ± 9.6). All SXB doses resulted in significant improvement (p < 0.05) relative to placebo for Vitality, with moderate ES. No significant differences versus placebo were observed for Role–Physical, Role–Emotional, or Mental Health domains.

Conclusion

Treatment with SXB was associated with a dose-dependent improvement in HRQoL, with the 9-g nightly dose demonstrating a positive impact on PCS and individual SF-36 domains of Vitality, GH, and Physical and Social Functioning.

Trial registration

NCT00049803.

Funding

Jazz Pharmaceuticals.

Health-related stigma as a determinant of functioning in young adults with narcolepsy

Symptoms of narcolepsy tend to arise during adolescence or young adulthood, a formative time in human development during which people are usually completing their education and launching a career. Little is known about the impact of narcolepsy on the social aspects of health-related quality of life in young adults. The purpose of this study was to examine relationships between health-related stigma, mood (anxiety and depression) and daytime functioning in young adults with narcolepsy compared to those without narcolepsy. Young adults (age 18–35) with narcolepsy (N = 122) and without narcolepsy (N = 93) were mailed a packet that included questionnaires and a self-addressed postage paid envelope. The questionnaire included demographic information and a composite of instruments including the SF 36, Functional Outcomes of Sleep Questionnaire (FOSQ), Fife Stigma Scale (FSS), Epworth Sleepiness Scale (ESS) and Hospital Anxiety and Depression Scale (HADS). Variable associations were assessed using descriptive statistics, ANOVA, Mann-Whitney U Test, correlations, stepwise multiple regression and path analysis. Young adults with narcolepsy perceived significantly more stigma and lower mood and health-related quality of life than young adults without narcolepsy (p<0.01). Health-related stigma was directly and indirectly associated with lower functioning through depressed mood. Fifty-two percent of the variance in functioning was explained by the final model in the young adults with narcolepsy. Health-related stigma in young adults with narcolepsy is at a level consistent with other chronic medical illnesses. Health-related stigma may be an important determinant of functioning in young adults with narcolepsy. Future work is indicated toward further characterizing stigma and developing interventions that address various domains of stigma in people with narcolepsy.

Narcolepsy and the Sickness Impact Profile: A general health status measure

Objective

We characterized functional impact of narcolepsy on patients using a general health status measure, the Sickness Impact Profile (SIP). It has 136 items grouped into 12 categories and 2 dimensions.

Methods

We ascertained patients with physician-diagnosed narcolepsy in King County, Washington using multiple overlapping methods over four years starting July 2001. We recruited 226 patients (mean age 48 years, 65% female) who underwent in-person interviews and completed: Epworth Sleepiness Scale (ESS), Ullanlinna Narcolepsy Scale (UNS), and SIP. Linear regression was used to assess correlations between measures.

Results

Mean percent of total dysfunction was higher for psychosocial dimension (13.2) and independent categories (13.4) than physical dimension (5.0). Mean percent of total dysfunction in descending order for categories was: Sleep and Rest (23.6), Alertness Behavior (22.6), and Recreation and Pastimes (20.6). Ten items were endorsed by at least a third of all patients but only two of them concerned sleep. Unexpectedly, among the top ten items were, “My sexual activity is decreased,” and “I forget a lot, for example, things that happened recently, where I put things, appointments.” Percent of overall dysfunction on SIP (mean 10.3) was significantly correlated with ESS (r=0.36, p<0.001) and UNS (r=0.47, p<0.001). In this population-based sample, mean percent of total dysfunction on SIP in patients with narcolepsy (10.3) was higher than previously reported in the general population (3.6) and similar to that in other chronic disabling conditions.

Discussion

The SIP correlated with ESS and UNS, and captured unique aspects of the impact of narcolepsy on patients.

Reward-based behaviors and emotional processing in human with narcolepsy-cataplexy

Major advances in the past decade have led a better understanding of the pathophysiology of narcolepsy with cataplexy (NC) caused by the early loss of hypothalamic hypocretin neurons. Although a role for hypocretin in the regulation of sleep/wakefulness state is widely recognized, other functions, not necessarily related to arousal, have been identified. Hence, the hypocretin system enhances signaling in the mesolimbic pathways regulating reward processing, emotion and mood regulation, and addiction. Although studies on hypocretin-deficient mice have shown that hypocretin plays an essential role in reward-seeking, depression-like behavior and addiction, results in human narcolepsy remained subject to debate. Most of studies revealed that hypocretin-deficient narcolepsy patients either drug-free or medicated with psychostimulant had preferences toward risky choices in a decision-making task under ambiguity together with higher frequency of depressive symptoms and binge eating disorder compared to controls. However, human studies mostly reported the lack of association with pathological impulsivity and gambling, and substance and alcohol abuse in the context of narcolepsy-cataplexy. Prospective larger studies are required to confirm these findings in drug-free and medicated patients with narcolepsy. Inclusion of patients with other central hypersomnias without hypocretin deficiency will provide answer to the major question of the role of the hypocretin system in reward-based behaviors and emotional processing in humans.

Excessive daytime sleepiness assessed by the Epworth Sleepiness Scale and its association with health related quality of life: a population-based study in China

Background

Excessive daytime sleepiness (EDS) is a common condition worldwide that has many negative effects on people who were afflicted with it, especially on their health-related quality of life (HRQOL). The Epworth Sleepiness Scale (ESS) is a commonly used method for evaluating EDS in English-speaking countries. This paper reported the prevalence of subjective EDS in China as assessed by the Mandarin version of the ESS; tested the scale’s response rate, reliability and validity; and investigated the relationship between ESS scores and HRQOL.

Methods

A population-based sample of 3600 residents was selected randomly in five cities in China. The demographic information was collected, subjective EDS was assessed by the Mandarin version of the ESS (ESS scores >10), and HRQOL was evaluated by the Mandarin version of the 36-item Short Form Health Survey (SF-36).

Results

The Mandarin version of ESS had very few missing responses, and the average response rate of its eight items was 97.92%. The split-half reliability coefficient and Cronbach’s α coefficient were 0.81 and 0.80, respectively. One factor was identified by factor analysis with an eigenvalue of 2.78. The ESS scores showed positive skewness in the selected sample, with a median (Q1, Q3) of 6 (3, 0). 644 (22.16%) respondents reported subjective EDS, and all of the scores of the eight dimensions of the SF-36 were negatively correlated with ESS scores.

Conclusions

The Mandarin version of ESS is an acceptable, reliable, and valid tool for measuring EDS. In addition, subjective EDS is common in China, based on the ESS results, and impairs HRQOL.

The burden of narcolepsy with cataplexy: how disease history and clinical features influence socio-economic outcomes

OBJECTIVE

To investigate in narcolepsy with cataplexy (NC) patients of working age (18-65 years) the influence of age at onset, age at diagnosis and clinical features on socio-occupational conditions, disease-related economic burden, and quality of life.

METHODS

One hundred consecutive patients underwent a semistructured interview on socio-occupational aspects, NC-related direct and indirect costs, and NC history. Questionnaires were used to evaluate excessive daytime sleepiness, cataplexy, depressive symptoms, and quality of life.

RESULTS

NC patients (51 males, mean age 37±11.5 years) had educational and occupational levels similar to those of the Italian population of the same age range, but married less often, especially if NC onset occurred at a young age. Total annual NC-related costs were €9814 ± 10,372 per patient. Multivariate analyses showed that patients with NC onset before the age of 30 years had a higher educational level, married less frequently, and were less frequently unemployed or inactive (retired, housewife). Patients diagnosed before the age of 30 years were less frequently unemployed or inactive, had fewer work changes, and had a better general health perception. Irresistible sleepiness was associated with work absences and higher indirect costs. Depressive symptoms were strongly associated with lower quality-of-life scores.

CONCLUSIONS

NC age at onset and at diagnosis modulates the disease-related burden. A diagnosis at a young age could improve patients' occupational prognosis, and their general health perception.

Executive control of attention in narcolepsy

Background

Narcolepsy with cataplexy (NC) is a disabling sleep disorder characterized by early loss of hypocretin neurons that project to areas involved in the attention network. We characterized the executive control of attention in drug-free patients with NC to determine whether the executive deficits observed in patients with NC are specific to the disease itself or whether they reflect performance changes due to the severity of excessive daytime sleepiness.

Methodology

Twenty-two patients with NC compared to 22 patients with narcolepsy without cataplexy (NwC) matched for age, gender, intellectual level, objective daytime sleepiness and number of sleep onset REM periods (SOREMPs) were studied. Thirty-two matched healthy controls were included. All participants underwent a standardized interview, completed questionnaires, and neuropsychological tests. All patients underwent a polysomnography followed by multiple sleep latency tests (MSLT), with neuropsychological evaluation performed the same day between MSLT sessions.

Principal Findings

Irrespective of diagnosis, patients reported higher self-reported attentional complaints associated with the intensity of depressive symptoms. Patients with NC performed slower and more variably on simple reaction time tasks than patients with NwC, who did not differ from controls. Patients with NC and NwC generally performed slower, reacted more variably, and made more errors than controls on executive functioning tests. Individual profile analyses showed a clear heterogeneity of the severity of executive deficit. This severity was related to objective sleepiness, higher number of SOREMPs on the MSLT, and lower intelligence quotient. The nature and severity of the executive deficits were unrelated to NC and NwC diagnosis.

Conclusions

We demonstrated that drug-free patients with NC and NwC complained of attention deficit, with altered executive control of attention being explained by the severity of objective sleepiness and global intellectual level. Further studies are needed to explore whether medications that promote wakefulness can improve the executive functions in narcolepsy.

Determinants of depressive symptoms in narcoleptic patients with and without cataplexy

The present prospective study assesses depressive symptoms in narcoleptic patients with (NC+) and without (NC-) cataplexy (46 women, 40 men) and age- and sex- matched healthy controls. Seventy patients were under treatment with stimulants and/or anticataplectics. All subjects completed the Beck Depression Inventory (BDI), the Zung Self-Rating Depression Scale (SDS), the Global Impression of Severity of Depression (GSD), the Profile of Mood States (POMS) and Epworth Sleepiness Scale. Patients with narcolepsy were more depressed than controls (higher scores in BDI, GSD, SDS, and POMS [in the total score and in all subscale scores]); however, between the NC+ and NC- patient groups, no differences were found. Our study shows that the women and the patients using antidepressants and stimulants (combination) have a higher probability for depressive symptoms independent of the presence of cataplexy. The lack of difference between NC+ and NC- in the level of depression supports the assumption that the major psychosocial burden in narcolepsy is not necessarily associated with the presence of cataplexy.

Narcolepsy: a review

Narcolepsy is a lifelong sleep disorder characterized by a classic tetrad of excessive daytime sleepiness with irresistible sleep attacks, cataplexy (sudden bilateral loss of muscle tone), hypnagogic hallucination, and sleep paralysis. There are two distinct groups of patients, ie, those having narcolepsy with cataplexy and those having narcolepsy without cataplexy. Narcolepsy affects 0.05% of the population. It has a negative effect on the quality of life of its sufferers and can restrict them from certain careers and activities. There have been advances in the understanding of the pathogenesis of narcolepsy. It is thought that narcolepsy with cataplexy is secondary to loss of hypothalamic hypocretin neurons in those genetically predisposed to the disorder by possession of human leukocyte antigen DQB1*0602. The diagnostic criteria for narcolepsy are based on symptoms, laboratory sleep tests, and serum levels of hypocretin. There is no cure for narcolepsy, and the present mainstay of treatment is pharmacological treatment along with lifestyle changes. Some novel treatments are also being developed and tried. This article critically appraises the evidence for diagnosis and treatment of narcolepsy.

A 5-year prospective cohort study on health-related quality of life in patients with narcolepsy

OBJECTIVE

To evaluate the 5-year variation of health-related quality of life (HRQoL) and mood symptoms in a cohort of patients with narcolepsy.

METHODS

Adults attending the Sleep Centre of the Department of Neurological Sciences, University of Bologna in 1997 and meeting the International Classification of Sleep Disorders-Revised criteria for the diagnosis of narcolepsy were eligible. Included patients self-administered the Medical Outcome Short Form-36 (SF-36) and the Zung depression scale (ZDS) prospectively in 1998 and 2003.

RESULTS

There was no significant difference between 1998 and 2003 measures of SF-36 and ZDS in the 54 patients included. About 25% of them showed moderate or severe mood symptoms in both observations. ZDS score (inversely) and duration of disease (directly) explained a percentage of variance of role physical, vitality (VT), social functioning (SF) and role emotional. At the second observation VT and SF had a further percentage of variance explained by excessive daytime sleepiness (EDS) and age at onset. Self-reported diabetes frequency doubled after 5 years (from 7% to 17%).

CONCLUSIONS

Patients with narcolepsy show a stable impairment of HRQoL in a 5-year period with respect to Italian normative data. Mood status and EDS negatively influence their HRQoL while disease duration has a positive influence.

The socio-economical burden of hypersomnia

OBJECTIVES

In the absence of socio-economical consequences of hypersomnia this study addresses the factual indirect and direct costs.

METHODS

Two thousand two hundred and eight patients with a hypersomnia diagnosis from 1998 to 2005 were identified in the Danish national patient registry (NPR), each compared with 4 age and gender adjusted, randomly chosen citizens selected from the Civil Registration System Statistics. The health cost was decomposed in direct and indirect yearly costs, including labor supply and social transfer payments. Direct costs included frequencies and costs of discharges and outpatient use by cost weights according to diagnosis related groups and specific outpatient prices based on data from The Danish Ministry of Health. The use of and costs of drugs was based on data from the Danish Medicines Agency. The frequencies and costs from primary sectors were based on data from The National Health Security. Indirect costs were based on income data from the coherent social statistics (CSS).

RESULTS

Patients with hypersomnia presented significant higher health related contact rate, expenses and medication use. No differences were identified in employment and income. The yearly sum of direct and indirect costs were yearly euro3402 vs. euro1212 in controls (P < 0.001), corresponding to a yearly excess costs euro2190. The patients presented higher transfer income, total euro889.

CONCLUSION

Hypersomnia patient present higher health and medication uses, and social transfer income and thus represent a significant socio-economical burden.

Anxiety and mood disorders in narcolepsy: a case-control study

INTRODUCTION

Narcolepsy is a primary sleeping disorder with excessive daytime sleepiness and cataplexy as core symptoms. There is increasing interest in the psychiatric phenotype of narcolepsy. Although many authors suggest an overrepresentation of mood disorders, few systematic studies have been performed and conflicting results have been reported. Anxiety disorders in narcolepsy have only received little attention.

METHODS

We performed a case-control study in 60 narcolepsy patients and 120 age- and sex-matched controls from a previous population study. The Schedules for Clinical Assessment in Neuropsychiatry were used to assess symptoms and diagnostic classifications of mood and anxiety disorders.

RESULTS

Symptoms of mood disorders were reported by about one third of patients. However, the prevalence of formal mood disorder diagnoses - including major depression - was not increased. In contrast, more than half of the narcolepsy patients had anxiety or panic attacks. Thirty-five percent of the patients could be diagnosed with anxiety disorder (odds ratio=15.6), with social phobia being the most important diagnosis. There was no influence of age, sex, duration of illness or medication use on the prevalence of mood or anxiety symptoms and disorders.

DISCUSSION

Anxiety disorders, especially panic attacks and social phobias, often affect patients with narcolepsy. Although symptoms of mood disorders are present in many patients, the prevalence of major depression is not increased. Anxiety and mood symptoms could be secondary complications of the chronic symptoms of narcolepsy. Recent studies have shown that narcolepsy is caused by defective hypocretin signaling. As hypocretin neurotransmission is also involved in stress regulation and addiction, this raises the possibility that mood and anxiety symptoms are primary disease phenomena in narcolepsy.

Prevalence of narcolepsy with cataplexy in Norway

OBJECTIVES

Narcolepsy is a lifelong disabling disorder that may be alleviated by relevant treatment. Patients frequently report 10-15 years from the first symptoms to the time they get the diagnosis and treatment can be started. In order to offer a sufficient diagnostic and therapeutic service to this patient group, a reliable estimation of the prevalence of the disorder is important. A study of the prevalence of narcolepsy with cataplexy in Norway was therefore undertaken.

MATERIALS AND METHODS

The Ullanlinna Narcolepsy scale (UNS) was sent to 14548 randomly selected Norwegians between 20 and 60 years. Additionally, the study included telephone interviews and clinical evaluation of responders with >or=14 points on the UNS, and in those with suspected narcolepsy, polygraphic sleep recordings and human leucocyte antigen (HLA)-typing.

RESULTS

A total of 8992 responders answered the questionnaire (response rate 61.8%), 267 had >or=14 points on the UNS, 156 were interviewed and 15 had sleep recordings. In two HLADQB1*0602-positive patients sleep recordings were compatible with narcolepsy.

CONCLUSIONS

The results indicate a prevalence of 0.022% and approximately 1000 patients with narcolepsy with cataplexy in Norway.

Narcolepsy and depression and the neurobiology of gammahydroxybutyrate

A voluminous literature describes the relationship between disturbed sleep and depression. The breakdown of sleep is one of the cardinal features of depression and often also heralds its onset. Frequent arousals, periods of wakefulness and a short sleep onset REM latency are typical polysomnographic features of depression. The short latency to REM sleep has been attributed to the combination of a monoaminergic deficiency and cholinergic supersensitivity and these irregularities have been proposed to form the biological basis of the disorder. A similar imbalance between monoaminergic and cholinergic neurotransmission has been found in narcolepsy, a condition in which frequent awakenings, periods of wakefulness and short sleep onset REM latencies are also characteristic findings during sleep. In many cases of narcolepsy, this imbalance appears to result from a deficiency of hypocretin but once established, whether in depression or narcolepsy, this disequilibrium sets the stage for the dissociation or premature appearance of REM sleep and for the dissociation of the motor inhibitory component of REM sleep or cataplexy. In the presence of this monoaminergic/cholinergic imbalance, gammahydroxybutyrate (GHB) may acutely further reduce the latency of REM sleep and induce cataplexy, in both patients with narcolepsy or depression. On the other hand, the repeated nocturnal application of GHB in patients with narcolepsy improves the continuity of sleep, prolongs the latency to REM sleep and prevents cataplexy. Evidence to date suggests that GHB may restore the normal balance between monoaminergic and cholinergic neurotransmission. As such, the repeated use of GHB at night and the stabilization of sleep over time makes GHB an effective treatment for narcolepsy and a potentially effective treatment for depression.

Sleep disorders and medical conditions in women. Proceedings of the Women & Sleep Workshop, National Sleep Foundation, Washington, DC, March 5-6, 2007

Sleep disorders affect women differently than they affect men and may have different manifestations and prevalences. With regard to obstructive sleep apnea (OSA), variations in symptoms may cause misdiagnoses and delay of appropriate treatment. The prevalence of OSA appears to increase markedly after the time of menopause. Although OSA as defined by the numbers of apneas/hypopneas may be less severe in women, its consequences are similar and perhaps worse. Therapeutic issues related to gender should be factored into the management of OSA. The prevalence of insomnia is significantly greater in women than in men throughout most of the life span. The ratio of insomnia in women to men is approximately 1.4:1.0, but the difference is minimal before puberty and increases steadily with age. Although much of the higher prevalence of insomnia in women may be attributable to the hormonal or psychological changes associated with major life transitions, some of the gender differences may result from the higher prevalence of depression and pain in women. Insomnia's negative impact on quality of life is important to address in women, given the high relative prevalence of insomnia as well as the comorbid disorders in this population. Gender differences in etiology and symptom manifestation in narcolepsy remain understudied in humans. There is little available scientific information to evaluate the clinical significance and specific consequences of the diagnosis of narcolepsy in women. Restless legs syndrome (RLS) is characterized by an urge to move the legs or other limbs during periods of rest or inactivity and may affect as much as 10% of the population. This condition is more likely to afflict women than men, and its risk is increased by pregnancy. Although RLS is associated with impaired quality of life, highly effective treatment is available.

Gray matter deficits in young adults with narcolepsy

OBJECTIVES

The aim of this study was to investigate gray matter volume changes in narcolepsy.

MATERIALS AND METHODS

An optimized voxel-based morphometry was conducted for 17 young adults with a sole diagnosis of human leukocyte antigen DQB(1) 0602 positive narcolepsy with cataplexy (26.6 +/- 5.2 years old) and 17 comparison subjects (24.6 +/- 4.9 years old) using 3 Tesla scanner. Gray matter volumes in the bilateral hypothalamic voxel of interests (VOI) were also calculated.

RESULTS

Compared with the comparison subjects, narcoleptic patients had gray matter volume decrease in the right hypothalamus and other regions including subcortical, prefrontal, limbic and occipital areas. Narcoleptic patients also had lower gray matter volume on predefined VOI at the bilateral hypothalamus, which correlated with the Ullanlinna Narcolepsy Scale score.

CONCLUSIONS

Current findings suggest that narcoleptic patients have structural abnormalities in hypothalamus, which might be related to the clinical manifestation of narcolepsy with cataplexy.

Quality of life in patients with narcolepsy: a WHOQOL-bref study

OBJECTIVE

To evaluate the perception of Quality of Life (QL) in Brazilian patients with narcolepsy.

METHOD

40 adult patients aged between 20 and 72 years (mean=41.55; SD=14.50); (28 F; 12M), with the diagnosis of chronic narcolepsy were followed up at the outpatient clinic (Patient Group). The Control Group was composed of 40 adults. The instrument utilized was the World Health Organization Quality of Life (WHOQOL-BREF).

RESULTS

The two groups were homogeneous and no difference was found with regards to age, sex, and demographic characteristics. The perception of QL in physical, psychological and social domains showed lower scores in those patients with narcolepsy than in the control group (p<0.05). Concerning physical domain, all the aspects evaluated were significantly impaired, in patient group, including sleep satisfaction (p<0.001); energy for daily activities (p=0.039); capacity to perform activities (p=0.001); and capacity to work (p=0.001).

CONCLUSION

The perception of QL showed severe impairment in patients with narcolepsy for physical, psychological and social domains.

Psychosocial and intellectual functioning in childhood narcolepsy

PURPOSE

This study reports the psychological assessment of 12 children referred to a narcolepsy clinic, using quantitative methods to describe intellectual and psychosocial functioning in childhood narcolepsy.

METHODS

The participants were six males and six females aged between 7-16 years (median age 10 years). The protocol included a clinical interview; the Wechsler Intelligence Scale for Children-III-UK; and the Parent version of the Achenbach Child Behaviour Checklist (CBCL).

RESULTS

Eleven children obtained an IQ in the average range (mean and median =100). However, a significant difference was found between verbal and performance scales in 42% of children, compared to WISC-III normative prevalence rates of 24%. CBCL results revealed that 10/12 children scored in the clinically significant range on the Total Score Index, with 9/12 obtaining scores in the significant range on the Internalizing Index. The majority of children presented with difficulties in discussing and describing distressing physical and psychological symptoms with parents and others.

CONCLUSIONS

These findings suggest that the psychosocial impact of narcolepsy extends beyond the effects of excessive sleepiness and that symptoms such as hallucinations can lead to significant psychological morbidity.

Antidepressant drugs for narcolepsy

BACKGROUND

Narcolepsy is a disorder of the central nervous system, the main symptoms of which are excessive daytime sleepiness (EDS) and cataplexy (an abrupt and reversible decrease in or loss of muscle tone, affecting the limbs or trunk or both, elicited by emotional stimuli). Narcolepsy has an adverse impact on people's quality of life. Together with stimulant drugs (used to control EDS), antidepressants are usually recommended to counteract cataplexy. In addition, some antidepressants are also reported to improve EDS.

OBJECTIVES

To evaluate the effects of antidepressant drugs on EDS, cataplexy, quality of life, and their side effects in people with narcolepsy.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2007), MEDLINE (1966 to 2007), EMBASE (1980 to 2007), PsycINFO (1872 to 2007), and CINAHL (1981 to 2007). Bibliographies of identified articles were reviewed to find additional references. Unpublished randomised trials were searched for by consulting governmental and non-governmental clinical trial registers, disease-specific websites, investigators and experts in the field, pharmaceutical companies/manufacturers.

SELECTION CRITERIA

Parallel or cross-over randomised or quasi-randomised controlled trials testing the treatment of narcolepsy with any type of antidepressant drug versus no treatment, placebo, or another antidepressant drug.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

Three cross-over and two parallel trials were included with a total of 246 participants. The methodological quality of all studies was unclear. As the trials tested different comparisons, or had a different design or dealt with different outcome measures, meta-analysis was not performed. In one cross-over trial (10 participants) femoxetine had no significant effect in eliminating or reducing EDS but significantly reduced cataplexy. Mild and transient side effects were reported in the femoxetine treatment period by two participants. In a second cross-over trial (56 participants) viloxazine significantly reduced EDS and cataplexy. In a third cross-over trial the authors inappropriately treated the trial design as a parallel study and no conclusions can be reached in favour of either drug. Two more trials with parallel design tested ritanserin versus placebo without finding differences of effectiveness in reducing EDS or cataplexy.

AUTHORS' CONCLUSIONS

There was no good quality evidence that antidepressants are effective for narcolepsy or improve quality of life. Despite the clinical consensus recommending antidepressants for cataplexy there is scarce evidence that antidepressants have a positive effect on this symptom. There is a clear need for well-designed randomised controlled trials to assess the effect of antidepressants on narcolepsy.

Therapies for narcolepsy with or without cataplexy: evidence-based review

(1) Narcolepsy is a rare disorder of unknown aetiology characterized by excessive daytime sleepiness and typically associated with cataplexy. It is extremely incapacitating, and frequently results in impaired psychosocial functioning and reduced work performance. Currently there is no cure for narcolepsy, so treatment focuses on control of symptoms.(2) Although the sympathomimetic stimulants, such as amphetamines or methylphenidate, are effective in improving excessive daytime sleepiness in patients with narcolepsy, they have the potential for dependence, have sometimes disabling sympathomimetic side-effects and are associated with tolerance.(3) To date, there is clear evidence of the efficacy of modafinil, armodafinil and sodium oxybate in patients with narcolepsy. Modafinil and armodafinil improve excessive daytime sleepiness symptoms and have little abuse potential, but have no effect on cataplexy, so other drugs, such as antidepressants, are required to control cataplexy attacks.(4) Sodium oxybate improves both excessive daytime sleepiness and cataplexy. However, there is potential for abuse and possibly dependence.