Validation of the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) questionnaire in pediatric patients with narcolepsy with cataplexy aged 7-16 years.

OBJECTIVE/BACKGROUND: The Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) measures daytime sleepiness, but had not previously been validated in children <12 years of age. PATIENTS/METHODS: Data from a sodium oxybate (SXB) study in pediatric participants with narcolepsy with cataplexy (ClinicalTrials.gov, NCT02221869) were used in this validation study. SXB-naive participants completed an open-label titration period prior to entering a 2-week stable-dose period; participants taking SXB at study entry entered a 3-week stable-dose period. RESULTS: The analysis population (N = 100) had a mean (SD) age of 11.9 (2.39) years. Internal consistency as assessed by Cronbach's alpha was 0.750 (95% CI, 0.681-0.819). The intraclass correlation coefficient for the test-retest reliability assessment (n = 64 with stable or no stimulant use at study entry) was 0.755 (95% CI, 0.626-0.844). Responsiveness to change, measured as the mean within-person change in 1-week ESS-CHAD score over time in SXB-naive participants (n = 59) from baseline (before taking SXB) to end of the stable-dose period (taking the titrated amount of SXB), was -6.31 (95% CI: -7.61, -5.00; nominal P < 0.0001). For convergent construct validity, the mean (SD) scores for female (n = 40) and male (n = 60) participants were 13.98 (4.440) and 14.65 (4.050), respectively (nominal P = 0.4430). For divergent construct validity, the mean (SD) scores were 16.31 (2.978) in the group who were taking neither SXB nor stimulants at study entry (n = 32) and 13.47 (4.400) in the group taking SXB with or without stimulants at study entry (n = 68; nominal P = 0.0003). CONCLUSIONS: This evidence supports the validity of the 1-week ESS-CHAD in a pediatric population with narcolepsy.

Developing an Alternative Version of the Epworth Sleepiness Scale to Assess Daytime Sleepiness in Adults with Physical or Mental Disabilities.

INTRODUCTION: Excessive daytime sleepiness (EDS) is a frequent symptom with many possible causes, and many of these can be treated. EDS and its underlying causes have been associated with various negative health consequences. Recognition of EDS is thus an important public health concern. The concept of EDS is, however, not yet well defined, and different measures are used to diagnose EDS. The Epworth Sleepiness Scale (ESS) is the most widely used tool to assess daytime sleepiness in a broad range of populations. Its applicability in patients exhibiting physical or mental disabilities, like older multimorbid patients, is limited, since the ESS was not developed and validated in this patient group. METHODS: Within an expert study with 35 sleep medicine experts and a pilot study with 52 geriatric in-patients, who frequently exhibit physical or mental disabilities, and patients' close relatives, we adapted the original ESS to develop an alternative version to assess daytime sleepiness in adults with physical or mental disabilities (ESS-ALT). RESULTS: In this adapted version, items 3 (sitting inactively in a public place) and 8 (sleepy in traffic) were replaced by 2 new items (sitting in a waiting room, sitting and eating a meal) and an interview format was used. This ESS-ALT achieved fewer missing responses (23 vs. 73%) and a higher level of internal consistency (Cronbach's α = 0.64 vs. 0.23) than the original ESS while keeping its somnificity structure. CONCLUSION: The ESS-ALT achieves better psychometric properties than the original ESS for individuals with physical or mental disabilities.

The effects of unintentional drowsiness on the velocity of eyelid movements during spontaneous blinks.

OBJECTIVE: Unintentional drowsiness, when we should be alert, as for example when driving a vehicle, can be very dangerous. In this investigation we examined the effects of unintentional drowsiness on the relative velocities of eyelid closing and reopening movements during spontaneous blinks. APPROACH: Twenty-four young adults volunteered to take part in this experiment, and 18 were finally accepted. They performed a 15 min visual reaction-time test at the same time of day and under the same environmental conditions with and without overnight sleep deprivation, one week apart. Their eyelid movements during blinks were monitored by a system of infrared reflectance blepharometry during each test. MAIN RESULTS: Very close relationships between the amplitude and maximum velocity of eyelid closing and reopening movements were confirmed. Frequency histograms of amplitude-velocity ratios (AVRs) for eyelid closing and reopening movements showed significant differences between alert and drowsy conditions. With drowsiness, eyelid movements became slower and AVRs increased for many but not all blinks. We also described a time-on-task effect on the relative velocities of eyelid movements which was more apparent in the drowsy condition. Eyelid movements became progressively slower during the first half of the test. This was presumably due to a short-lived alerting effect of starting the test. SIGNIFICANCE: The relative velocity of eyelid closing and reopening movements during spontaneous blinks decreases with unintentional drowsiness but is sensitive to the brief alerting stimulus of starting a reaction-time test.

Assessing narcolepsy with cataplexy in children and adolescents: development of a cataplexy diary and the ESS-CHAD.

OBJECTIVE: The aim of this study was to qualitatively evaluate concepts for incorporation into a daily diary to capture cataplexy frequency and to assess the content validity of the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) in pediatric patients with narcolepsy. PATIENTS AND METHODS: Face-to-face concept elicitation and cognitive interviews were conducted with children (7-9 years; n=13) and adolescents (10-17 years; n=16) who have narcolepsy with cataplexy, and their parents/caregivers. RESULTS: Similarities and differences were noted between narcolepsy concepts described by children and their parents/caregivers, suggesting some different but complementary perspectives; parents may not recognize cataplexy symptoms/triggers as well as children, but parents have greater recognition of the circumstances of falling asleep. Cataplexy diary modifications included changes in definitions and examples of cataplexy, using child-friendly terminology, adding a quantitative question to determine daily frequency, and standardizing the questionnaire for evening administration with self-completion by the child. Modifications were made to ESS-CHAD for child-friendly wording and to ensure that items reflect activities (eating, watching TV/video) and environments (school, bus/car transport) in which children are likely to participate. Two ESS-CHAD versions were proposed: one with a 1-month recall period, for general use, and the other with a recall period of "since your last study visit," for research, which could be shorter or longer than 1 month (as short as 1 week). CONCLUSION: The cataplexy diary and ESS-CHAD were modified for the assessment of children and adolescents. Further psychometric validation is recommended. These measures are being used in a Phase III, placebo-controlled clinical trial of sodium oxybate in children and adolescents with narcolepsy.

Assessing sleepiness and cataplexy in children and adolescents with narcolepsy: a review of current patient-reported measures.

OBJECTIVE: The objective of this study was to review patient-reported outcome measures assessing excessive daytime sleepiness (EDS) or cataplexy in children or adolescents to determine their usefulness and limitations in pediatric narcolepsy assessment. METHODS: Searches were performed in Embase and Medline for pediatric measures of EDS and cataplexy that are either patient- or proxy-reported, and searches of http://www.clinicaltrials.gov/ were conducted for studies in narcolepsy that included at least one patient-reported measure. Further review was performed if sleepiness questionnaires (child or proxy-reported), sleep questionnaires that may contain sleepiness questions, proxy-reported child behavior questionnaires, or information on cataplexy measures were mentioned. RESULTS: All self-reported cataplexy questionnaires from among 27 citations were study-specific diaries and were not identifiable as a recognized validated questionnaire. For EDS, 118 of 401 abstracts were further reviewed and the names of 21 questionnaires identified, of which eight questionnaires did not return additional citations of their validation. The Epworth Sleepiness Scale (ESS) or a modified version was the most frequently used measure of EDS. Although all measures were associated with limitations for use in the pediatric population, the ESS has been successfully used in adolescents and was deemed readily amenable to further modification for children. CONCLUSIONS: There remains a dearth of validated measures for assessing EDS and cataplexy in children and adolescents with narcolepsy. The need for these measures may be filled by modification or adaptation of existing adult measures; a daily cataplexy diary and the ESS may be readily modified to make them child-friendly with regard to wording and settings, but should still undergo psychometric validation.

Validation of the Epworth Sleepiness Scale for Children and Adolescents using Rasch analysis.

OBJECTIVE: A validated measure of daytime sleepiness for adolescents is needed to better explore emerging relationships between sleepiness and the mental and physical health of adolescents. The Epworth Sleepiness Scale (ESS) is a widely used scale for daytime sleepiness in adults but contains references to alcohol and driving. The Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) has been proposed as the official modified version of the ESS for children and adolescents. This study describes the psychometric analysis of the ESS-CHAD as a measure of daytime sleepiness for adolescents. METHODS: The ESS-CHAD was completed by 297 adolescents, 12-18 years old, from two independent schools in Victoria, Australia. Exploratory factor analysis and Rasch analysis was conducted to determine the validity of the scale. RESULTS: Exploratory factor analysis and Rasch analysis indicated that ESS-CHAD has internal validity and a unidimensional structure with good model fit. Rasch analysis of four subgroups based on gender and year-level were consistent with the overall results. The results were consistent with published ESS results, which strongly indicates that the changes to the scale do not affect the scale's capacity to measure daytime sleepiness. CONCLUSIONS: It is concluded that the ESS-CHAD is a reliable and internally valid measure of daytime sleepiness in adolescents 12-18 years old. Further studies are needed to establish the internal validity of the ESS-CHAD for children under 12 years, and to establish external validity and accurate cut-off points for children and adolescents.

The reliability and validity of the Korean version of the Epworth sleepiness scale.

OBJECTIVE: The Epworth sleepiness scale (ESS) is widely used to measure the subject's average sleep propensity across those different situations in daily life, particularly in patients with sleep-disordered breathing. The purposes of this study were to test the hypothesis that the Korean version of the ESS (KESS) is valid and evaluate its usefulness. MATERIALS AND METHODS: We developed the KESS, which involved translating into Korean and then translating back into English to check its accuracy. A total of 273 participants (181 obstructive sleep apnea (OSA)-37 mild, 61 moderate, 83 severe, 32 simple snoring and 60 normal) were included in this study. All subjects completed the overnight polysomnograph and 53 of the total subjects were randomly selected for a retest with the questionnaire approximately 2∼4 weeks later. The associations between KESS and the degree of OSA were examined through ANCOVA, adjusted for age, sex and BMI. RESULTS: The total score and each item's score of KESS in patients with OSA were significantly higher than subjects with normal controls (p < 0.01). As the severity of OSA increased, the KESS showed significantly increasing patterns (p for trend <0.01). The KESS in patient groups showed good internal consistency (Cronbach's α = 0.90) and test-retest reliability (r = 0.78 to 0.93). CONCLUSION: The KESS is a reliable and valid tool for screening patients with daytime sleepiness in Korea.

Portuguese-language version of the Epworth sleepiness scale: validation for use in Brazil.

OBJECTIVE: The aim of this study was to develop a Portuguese-language version of the Epworth sleepiness scale (ESS) for use in Brazil. METHODS: The steps involved in creating the ESS in Brazilian Portuguese (ESS-BR) were as follows: translation; back-translation; comparison (by a committee) between the translation and the back-translation; and testing in bilingual individuals. The ESS-BR was applied to a group of patients who were submitted to overnight polysomnography in order to identify obstructive sleep apnea-hypopnea syndrome (OSAHS), insomnia and primary snoring. A control group was composed of subjects with a history of normal sleep habits, without reported snoring. RESULTS: A total of 114 patients and 21 controls were included. The 8-item scores of the ESS-BR had an overall reliability coefficient of 0.83. The study group was composed of 59 patients with OSAHS, 34 patients with primary snoring and 21 patients with insomnia. One-way ANOVA demonstrated significant differences in ESS-BR scores among the four diagnostic groups (p < 0.001). Post-hoc tests between groups showed that the ESS-BR scores of the patients with insomnia did not differ from those of the controls (p > 0.05). The ESS-BR scores were significantly higher for OSAHS patients and for primary snorers than for controls (p < 0.05). In addition, the scores for OSAHS patients were significantly higher than were those for primary snorers (p < 0.05). CONCLUSIONS: The results of the present study demonstrate that the ESS-BR is a valid and reliable instrument for the assessment of daytime sleepiness, equivalent to its original version when applied to individuals who speak Brazilian Portuguese.

Portuguese-language version of the Epworth sleepiness scale: validation for use in Brazil / Validação da escala de sonolência de Epworth em português para uso no Brasil

OBJECTIVE: The aim of this study was to develop a Portuguese-language version of the Epworth sleepiness scale (ESS) for use in Brazil. METHODS: The steps involved in creating the ESS in Brazilian Portuguese (ESS-BR) were as follows: translation; back-translation; comparison (by a committee) between the translation and the back-translation; and testing in bilingual individuals. The ESS-BR was applied to a group of patients who were submitted to overnight polysomnography in order to identify obstructive sleep apnea-hypopnea syndrome (OSAHS), insomnia and primary snoring. A control group was composed of subjects with a history of normal sleep habits, without reported snoring. RESULTS: A total of 114 patients and 21 controls were included. The 8-item scores of the ESS-BR had an overall reliability coefficient of 0.83. The study group was composed of 59 patients with OSAHS, 34 patients with primary snoring and 21 patients with insomnia. One-way ANOVA demonstrated significant differences in ESS-BR scores among the four diagnostic groups (p < 0.001). Post-hoc tests between groups showed that the ESS-BR scores of the patients with insomnia did not differ from those of the controls (p > 0.05). The ESS-BR scores were significantly higher for OSAHS patients and for primary snorers than for controls (p < 0.05). In addition, the scores for OSAHS patients were significantly higher than were those for primary snorers (p < 0.05). CONCLUSIONS: The results of the present study demonstrate that the ESS-BR is a valid and reliable instrument for the assessment of daytime sleepiness, equivalent to its original version when applied to individuals who speak Brazilian Portuguese.

OBJETIVO: Desenvolver uma versão da escala de sonolência de Epworth (ESE) para o português para uso no Brasil. MÉTODOS: A versão no português do Brasil (ESE-BR) foi desenvolvida de acordo com as seguintes etapas: tradução; retrotradução; comparação entre a tradução e a retrotradução (por um comitê); e aplicação em indivíduos bilíngues. A ESE-BR foi aplicada a um grupo de pacientes submetidos à polissonografia de noite inteira para identificar síndrome da apneia-hipopneia obstrutiva do sono (SAHOS), insônia e ronco primário. Um grupo controle foi composto de indivíduos com história de hábitos normais de sono, sem ronco aparente. RESULTADOS: Um total de 114 pacientes e 21 controles foram incluídos. Os 8 itens do ESE-BR tiveram um coeficiente de confiabilidade total de 0,83. O grupo em estudo foi composto por 59 pacientes com SAHOS, 34 pacientes com ronco primário e 21 pacientes com insônia. One-way ANOVA demonstrou diferenças significativas nos escores do ESE-BR entre os quatro grupos diagnósticos (p < 0,001). Testes post hoc entre grupos pareados mostraram que os escores do ESE-BR para insones não diferiram daqueles dos controles (p > 0,05). Os escores dos pacientes com SAHOS e nos roncadores primários foram significativamente maiores que os dos controles (p < 0,05). Além disso, os escores para pacientes com SAHOS foram significativamente maiores do que os daqueles com ronco primário (p < 0,05). CONCLUSÕES: Os resultados do presente estudo demonstraram que a ESE-BR é um instrumento válido e confiável para a avaliação da sonolência diurna e equivalente a sua versão original, quando aplicada em indivíduos que falam português do Brasil

The effect of blinks and saccadic eye movements on visual reaction times.

Vision is suppressed during blinks and saccadic eye movements. We hypothesized that visual reaction times (RTs) in a vigilance test would be significantly increased when a blink or a saccade happened to coincide with the stimulus onset. Thirty healthy volunteers each performed a visual RT test for 15 min while their eye and eyelid movements were monitored by a system of infrared reflectance oculography. RTs increased significantly, many by more than 200 msec, when a blink occurred between 75 msec before and up to 150 msec after the stimulus onset. A similar result was observed with saccades that started 75 to 150 msec after the stimulus. Vision or attention was evidently inhibited before each blink and for longer than the saccades lasted. We suggest that visual suppression is involved in this process, which could explain some of the normal variability in RTs over periods of seconds that has not been adequately explained before.

Development of a Japanese version of the Epworth Sleepiness Scale (JESS) based on item response theory.

BACKGROUND: Various Japanese versions of the Epworth Sleepiness Scale (ESS) have been used, but none was developed via standard procedures. Here we report on the construction and testing of the developer-authorized Japanese version of the ESS (JESS). METHODS: Developing the JESS involved translations, back translations, a pilot study, and psychometric testing. We identified questions in the ESS that were difficult to answer or were inappropriate in Japan, proposed possible replacements for those questions, and tested them with analyses based on item response theory (IRT) and classical test theory. The subjects were healthy people and patients with narcolepsy, idiopathic hypersomnia, or obstructive sleep apnea syndrome. RESULTS: We identified two of our proposed questions as appropriate replacements for two problematic questions in the ESS. The JESS had very few missing data. Internal consistency reliability and test-retest reliability were high. The patients had significantly higher JESS scores than did the healthy people, and higher JESS scores were associated with worse daytime function, as measured with the Pittsburgh Sleep Quality Index. CONCLUSIONS: In Japan, the JESS provides reliable and valid information on daytime sleepiness. Researchers who use the ESS with other populations should combine their knowledge of local conditions with the results of psychometric tests.

Effects of caffeine on alertness as measured by infrared reflectance oculography.

RATIONALE: Caffeine is a well-known stimulant that can be used to increase alertness and performance especially in low arousal situations such as monotonous highway driving or after sleep deprivation. The effects of caffeine in rested, alert, participants are less clear, and this may be attributable to difficulties in objectively assessing small changes in alertness. OBJECTIVES: The present study examined the effects of caffeine in non-sleep-deprived participants with methods that have previously been shown to be sensitive to changes in alertness. In order to avoid confounding results, low, or non-users of caffeine, were sought as participants. MATERIALS AND METHODS: Twelve subjects participated in a within-subjects double-blind placebo-controlled design study and were administered either a capsule containing 200 mg of caffeine or placebo on two separate days. Ten-minute long tests of vigilance were performed at baseline and then at 30, 60, 120, 180, and 240 min after swallowing the capsule. During vigilance tests, eye blink variables were measured using infrared reflectance oculography and converted into a drowsiness score, Johns Drowsiness Scale (JDS). RESULTS: Caffeine significantly reduced JDS scores (drowsiness) and reaction times, and these changes persisted for 3 to 4 h. Self reports of sleepiness were not as sensitive, with Karolinska Sleepiness Scale scores only being significantly lower in the caffeine compared to placebo condition at 30 min post capsule administration. CONCLUSIONS: The results demonstrated that despite being well rested, administration of caffeine significantly increased alertness and enhanced performance, and these changes were able to be detected with the JDS.

Distinguishing sleep disorders from seizures: diagnosing bumps in the night.

BACKGROUND: Abnormal paroxysmal events in sleep may be parasomnias or epileptic seizures. In nocturnal frontal lobe epilepsy (NFLE), the unusual seizure features often lead to diagnostic confusion with nonepileptic parasomnias; video-electroencephalography monitoring is usually required to make the diagnosis. OBJECTIVE: To examine the reliability of the clinical history in diagnosing NFLE, using the Frontal Lobe Epilepsy and Parasomnias (FLEP) scale. DESIGN: The FLEP scale, comprising specific questions reflecting the diagnostic features of NFLE and parasomnias, was developed by an expert panel following review of the literature. It was then validated in a sample of individuals with firmly diagnosed nocturnal events. SETTING: Patients were recruited after appropriate diagnostic workup in tertiary sleep and epilepsy referral centers in Melbourne, Australia. PARTICIPANTS: Sixty-two patients (45 males) [corrected] with paroxysmal nocturnal events. Intervention Two independent interviews were conducted in each case, with the patient and a witness, by researchers blinded to the diagnosis. MAIN OUTCOME MEASURE: The diagnosis obtained from scores on the FLEP scale was compared with the confirmed diagnosis in each patient. RESULTS: Nocturnal frontal lobe epilepsy was correctly diagnosed from the FLEP score in 31 of 31 patients, with a sensitivity of 1.0 (95% confidence interval [CI], 0.85-1.00), specificity of 0.90 (95% CI, 0.73-0.97), positive predictive value of 0.91 (95% CI, 0.75-0.97), and negative predictive value of 1.00 (95% CI, 0.85-1.00). CONCLUSIONS: A diagnosis of NFLE can be made reliably using the clinical features identified in the FLEP scale. This may reduce the requirement for tertiary referral and extensive inpatient monitoring.

Validation of a Chinese version of the Epworth sleepiness scale.

Epworth sleepiness scale (ESS) is widely used to evaluate degree of somnolence among Chinese patients with sleep-disordered breathing. Yet no Mandarin-Chinese translation has ever reported its validation data. In this study we translated and validated the ESS into Mandarin Chinese (CESS). We found, in 31 bilingual patients' responses to the CESS and the English ESS obtained 1-2 weeks apart did not differ significantly (10.5 +/- 3.7 vs. 9.6 +/- 3.9, p = 0.32, Wilcoxon's signed rank test) and were significantly correlated (Spearman's p = 0.67, p = 0.0004). A total of 359 sleep-disordered breathing subjects were enrolled into the validation study in a prospective manner. The CESS showed acceptable internal consistency (Cronbach's alpha = 0.81). Thirty out of these patients answered CESS twice at an interval of 2-4 weeks, to yield an acceptable level of test-retest reliability (p = 0.74, p = 0.001). The respiratory disturbance indices obtained from 251 out of 359 subjects were significantly correlated with their CESS scores (p = 0.22, p < 0.001). The standard response mean of CESS was 0.86 as obtained from 94 out of 359 subjects who had initial control of their symptoms at 3 months after radio-frequency palate surgery. We conclude that the CESS is reliable in both a linguistic and a test-retest sense, and appears to be valid and sensitive to clinical change. The CESS could be used to advantage among other Mandarin-speaking subjects as a standardised screening test of sleepiness in daily life.

Sleep propensity varies with behaviour and the situation in which it is measured: the concept of somnificity.

It is self-evident that we fall asleep more readily when lying down than when standing up. Nevertheless, the influence of this and more subtle changes in posture, activity and the situation in which sleep propensity is measured have been largely ignored. The term somnificity is introduced here, defined as the general characteristic of a posture, activity and situation that reflects its capacity to facilitate sleep-onset in a majority of subjects. The relative somnificities of different activities and situations in the Epworth Sleepiness Scale (ESS) were investigated in 23 groups, involving 2802 subjects from seven different countries. The means of the different ESS item-scores were ranked from highest to lowest in each group. There was a high concordance (Kendall's C=0.84, P < 0.0001) among these ranks for all groups, whether of normal subjects or patients with sleep disorders, regardless of age, sex, or average sleepiness in daily life assessed by total Epworth scores. The ESS item-ranks formed an ordinal scale of somnificities with five different levels. Analysis of raw ESS item-scores for all 987 individual Australian subjects showed the same pattern of somnificities with six different levels, but with a lower concordance (C=0.39, P < 0.0001). This was probably because of subject x situation-specific interactions that were averaged within groups. A conceptual model of sleepiness is outlined that includes interactions between separate sleep and wake drives as a possible way of including behavioural and situational influences on sleep propensity.