The clinical value of the maintenance of wakefulness test (MWT) in the differentiation of children with attention deficit hyperactivity disorder (ADHD) and disorders of excessive somnolence

Summary Introduction   Attention deficit hyperactivity disorder is one of the most common child and adolescent psychiatric disorders. Probably a dysfunctional arousal regulation may play an important role in its pathogenesis. According to this hypothesis ADHD children may present an hypoarousal state with impaired daytime vigilance when confrontated with monotonous, repetetive tasks. Methods   We assessed the daytime wakefulness of 23 ADHD children and 6 children with excessive somnolence (narcolepsy, idiopathic CNS hypersomnia) using the Maintenance of Wakefulness Test (MWT) as a measure to determine objectively a subjects' ability to stay awake under soporific conditions. Results   Results indicate that there is no impaired daytime wakefulness in ADHD children, whether their nighttime sleep was disturbed or not. Mean sleep latencies across all MWT trials were similar for both groups groups (17.2 min. vs 16.3 min). In contrast children with an increased daytime sleepiness presented a shortened mean sleep latency during the trials (8.9 min). Aditionally more children of this group fell asleep during MWT compared to ADHD children (72 % vs 40.6 %). Conclusion   We speculate that due to the occurrence of attention problems in both disorders, the MWT might become a feasable, objective instrument in clinical practice for differential diagnostic.     

Sensitivity and specificity of the multiple sleep latency test (MSLT), the maintenance of wakefulness test and the epworth sleepiness scale: failure of the MSLT as a gold standard

Excessive daytime sleepiness (EDS) is an important symptom that needs to be quantified, but there is confusion over the best way to do this. Three of the most commonly used tests: the multiple sleep latency test (MSLT), the maintenance of wakefulness test (MWT) and the Epworth sleepiness scale (ESS) give results that are significantly correlated in a statistical sense, but are not closely related. The purpose of this investigation was to help clarify this problem. Previously published data from several investigations were used to calculate the reference range of normal values for each test, defined by the mean+/-2 SD or by the 2.5 and 97.5 percentiles. The 'rule of thumb' that many people rely on to interpret MSLT results is shown here to be misleading. Previously published results from each test were also available for narcoleptic patients who were drug-free at the time and who by definition had EDS. This enabled the sensitivity and specificity of the three tests to be compared for the first time, in their ability to distinguish the EDS of narcolepsy from the daytime sleepiness of normal subjects. The receiver operator characteristic curves clearly showed that the ESS is the most discriminating test, the MWT is next best and the MSLT the least discriminating test of daytime sleepiness. The MSLT can no longer be considered the gold standard for such tests.     

Sustained attention to response task (SART) shows impaired vigilance in a spectrum of disorders of excessive daytime sleepiness

The sustained attention to response task comprises withholding key presses to one in nine of 225 target stimuli; it proved to be a sensitive measure of vigilance in a small group of narcoleptics. We studied sustained attention to response task results in 96 patients from a tertiary narcolepsy referral centre. Diagnoses according to ICSD-2 criteria were narcolepsy with (n=42) and without cataplexy (n=5), idiopathic hypersomnia without long sleep time (n=37), and obstructive sleep apnoea syndrome (n=12). The sustained attention to response task was administered prior to each of five multiple sleep latency test sessions. Analysis concerned error rates, mean reaction time, reaction time variability and post-error slowing, as well as the correlation of sustained attention to response task results with mean latency of the multiple sleep latency test and possible time of day influences. Median sustained attention to response task error scores ranged from 8.4 to 11.1, and mean reaction times from 332 to 366ms. Sustained attention to response task error score and mean reaction time did not differ significantly between patient groups. Sustained attention to response task error score did not correlate with multiple sleep latency test sleep latency. Reaction time was more variable as the error score was higher. Sustained attention to response task error score was highest for the first session. We conclude that a high sustained attention to response task error rate reflects vigilance impairment in excessive daytime sleepiness irrespective of its cause. The sustained attention to response task and the multiple sleep latency test reflect different aspects of sleep/wakefulness and are complementary.     

Efficacy of modafinil on excessive daytime sleepiness in Prader-Willi syndrome

Excessive daytime sleepiness is a frequent and a highly disruptive symptom to the daily routine of children with Prader-Willi Syndrome (PWS) and their families. The objective of the study was to evaluate the efficacy of modafinil, a central stimulant, on excessive daytime sleepiness in children and adolescents with PWS. The efficacy of modafinil was evaluated in this open label pilot study comparing the Epworth sleepiness scale before and after treatment. Ten patients with molecularly confirmed PWS and a complaint of excessive daytime sleepiness underwent a night-time sleep recording and multiple sleep latency tests. One patient was excluded because of severe obstructive sleep apnea syndrome. Nine patients (4 males) with median age of 16 years (8-21) received modafinil at a starting dose of 100 mg/day. We found that all patients had excessive daytime sleepiness with an Epworth sleepiness scale at 14 (11-20) and mean sleep latency on multiple sleep latency tests at 5 (3-6) minutes. Moreover, six patients had at least two sleep-onset rapid eye movement periods showing a narcolepsy-like phenotype. Modafinil significantly improved sleepiness in all patients on the Epworth sleepiness scale from 14 (11-20) to 4 (3-12), (P = 0.007). Body mass index of the patients did not change significantly under treatment. No side effects were reported, and the drug was well-tolerated. We posit that this open label case series shows good efficacy of modafinil in nine children and adolescents with PWS.     

Determinants of excessive daytime sleepiness in a French community-dwelling elderly population

Epidemiological studies have suggested that excessive daytime sleepiness (EDS) is associated with depression, but the association between EDS and other psychiatric disorders has not been investigated. The aim of this study was to investigate the association of EDS with a wide range of psychiatric disorders and health-related conditions in the elderly population. Two thousand two hundred and fifty-nine non-institutionalised persons aged 65-years and over randomly recruited from the Montpellier district, France, completed the Epworth Sleepiness Scale (ESS). Psychiatric status was assessed by the Mini International Neuropsychiatric Interview and demographic and other health information was obtained. This cross-sectional study was conducted from March 1999 to February 2001. Men were significantly more likely to report EDS (ESS score>10) compared with women (12.0% versus 6.0% respectively). EDS was significantly associated in univariate analyses with chronic diseases, early awakening, snoring, severity of depression and lifetime prevalence of manic and hypomanic episodes. A multivariate analysis revealed that the lifetime prevalence of manic and hypomanic episodes, snoring and gender (male) were independently associated with EDS. No independent association with other psychiatric disorders was found.     

Excessive daytime sleepiness in patients suffering from different levels of obstructive sleep apnoea syndrome

Excessive daytime sleepiness (EDS) is a frequent symptom of patients with obstructive sleep apnoea (OSA). EDS is a high-risk factor for accidents at work and on the road. Thirty untreated patients with different levels of severity of OSA were studied concerning night sleep and EDS. The criterion for severity was the respiratory disturbance index (RDI): 15 patients were classified as 'moderately' apnoeic (RDI < 40), 15 as 'severely' apnoeic (RDI > 40). Following night-time polysomnography, objective and subjective aspects of EDS were studied. To assess objective EDS the Maintenance of Wakefulness Test (MWT) and a computer-based vigilance performance test were used. Subjective EDS was determined using the Stanford Sleepiness Scale (SSS), the Epworth Sleepiness Scale (ESS) and the Visual Analogue Scales for Performance (VAS-P) and Tiredness (VAS-T). Well-being was assessed using the Scale of Well-Being by von Zerssen (Bf-S/Bf-S'). Severe apnoea patients spent more time in stage 1 and less in slow-wave sleep. MWT latencies tended to be shorter in the severe apnoea group. Vigilance testing revealed no group differences. Patients with moderate apnoea described themselves as more impaired in all subjective scales, but only SSS scores reached statistical significance. Our results suggest that there is no simple correlation between polysomnographic and respiratory sleep variables at night on the one hand, and the extent of EDS on the other hand. Furthermore, subjective and objective evaluation of EDS does not yield the same results. New approaches which allow a more detailed analysis of night sleep and daytime function are required to identify high-risked patients.     

Sleep disordered breathing and daytime sleepiness are associated with poor academic performance in teenagers. A study using the Pediatric Daytime Sleepiness Scale (PDSS)

STUDY OBJECTIVES: Inadequate sleep and sleep disordered breathing (SDB) can impair learning skills. Questionnaires used to evaluate sleepiness in adults are usually inadequate for adolescents. We conducted a study to evaluate the performance of a Spanish version of the Pediatric Daytime Sleepiness Scale (PDSS) and to assess the impact of sleepiness and SDB on academic performance. DESIGN: A cross-sectional survey of students from 7 schools in 4 cities of Argentina. MEASUREMENTS: A questionnaire with a Spanish version of the PDSS was used. Questions on the occurrence of snoring and witnessed apneas were answered by the parents. Mathematics and language grades were used as indicators of academic performance. PARTICIPANTS: The sample included 2,884 students (50% males; age: 13.3 +/- 1.5 years) RESULTS: Response rate was 85%; 678 cases were excluded due to missing data. Half the students slept <9 h per night on weekdays. The mean PDSS value was 15.74 +/- 5.93. Parental reporting of snoring occurred in 511 subjects (23%); snoring was occasional in 14% and frequent in 9%. Apneas were witnessed in 237 cases (11%), being frequent in 4% and occasional in 7%. Frequent snorers had higher mean PDSS scores than occasional or nonsnorers (18 +/- 5, 15.7 +/- 6 and 15.5 +/- 6, respectively; P < 0.001). Reported snoring or apneas and the PDSS were significant univariate predictors of failure and remained significant in multivariate logistic regression analysis after adjusting for age, sex, body mass index, specific school attended, and sleep habits. CONCLUSIONS: Insufficient hours of sleep were prevalent in this population. The Spanish version of the PDSS was a reliable tool in middle-school-aged children. Reports of snoring or witnessed apneas and daytime sleepiness as measured by PDSS were independent predictors of poor academic performance.     

The impact of daytime sleepiness on the school performance of college students with attention deficit hyperactivity disorder (ADHD): a prospective longitudinal study

This prospective longitudinal study evaluated the impact of daytime sleepiness on the school performance of 62 college students diagnosed comprehensively with attention deficit hyperactivity disorder. The primary goal of the study was to determine if self‐reported daytime sleepiness rated at the beginning of the academic year could predict academic and overall functioning at the end of the academic year while also considering potentially important covariates, including symptoms of inattention, hyperactivity and impulsivity, medication status and whether or not students lived at home or on‐campus. Self‐reported daytime sleepiness predicted longitudinally school maladjustment, overall functional impairment and the number of D and F grades (i.e. poor and failing) students received in courses above and beyond both self‐ and parent‐report of symptoms, but did not predict overall grade point average. Living at home served as a protective factor and was associated with less school maladjustment and overall impairment. Gender was the only significant predictor in the overall grade point average model, with female gender associated with higher overall grades. The implications of these findings for monitoring and treatment of sleep disturbances in college students with attention deficit hyperactivity disorder are discussed.     

Estimating daytime sleepiness with previous night electroencephalography,electrooculography, and electromyography spectrograms in patients with suspected sleep apnea using a convolutional neural network

A common symptom of obstructive sleep apnea (OSA) is excessive daytime sleepiness (EDS). The gold standard test for EDS is the multiple sleep latency test (MSLT). However, due to its high cost, MSLT is not routinely conducted for OSA patients and EDS is instead evaluated using sleep questionnaires. This is problematic however, since sleep questionnaires are subjective and correlate poorly with the MSLT. Therefore, new objective tools are needed for reliable evaluation of EDS. The aim of this study was to test our hypothesis that EDS can be estimated with neural network analysis of previous night polysomnographic signals. We trained a convolutional neural network (CNN) classifier using electroencephalography, electrooculography, and chin electromyography signals from 2,014 patients with suspected OSA. The CNN was trained to classify the patients into four sleepiness categories based on their mean sleep latency (MSL); severe (MSL < 5min), moderate (5 ≤ MSL < 10), mild (10 ≤ MSL < 15), and normal (MSL ≥ 15). The CNN classified patients to the four sleepiness categories with an overall accuracy of 60.6% and Cohen’s kappa value of 0.464. In two-group classification scheme with sleepy (MSL < 10 min) and non-sleepy (MSL ≥ 10) patients, the CNN achieved an accuracy of 77.2%, with sensitivity of 76.5%, and specificity of 77.9%. Our results show that previous night’s polysomnographic signals can be used for objective estimation of EDS with at least moderate accuracy. Since the diagnosis of OSA is currently confirmed by polysomnography, the classifier could be used simultaneously to get an objective estimate of the daytime sleepiness with minimal extra workload.     

Microsleep as a marker of sleepiness in obstructive sleep apnea patients

We hypothesized that: (a) the presence of microsleep (MS) during a Maintenance Wakefulness Test (MWT) trial may represent a reliable marker of sleepiness in obstructive sleep apnea (OSA) patients; (b) the number of MSs will be higher in sleepy versus non‐sleepy patients with a borderline MWT mean sleep latency; and (c) scoring MS during MWT analysis may help physicians to recognize patients with a higher degree of sleepiness. We analysed the MWT data of 112 treatment‐naïve OSA patients: 20 with short sleep latency (SL, sleep latency <12.8 min), 43 with borderline latency (BL, sleep latency between 12.8 and 32.6 min) and 49 with normal latency (NL, sleep latency >32.6 min). Microsleep was identified in all SL, in 42 BL and in 18 NL patients, with a median latency of 5.6 min. Accordingly, patients were classified into two subgroups: group A (n = 43) with microsleep latency <5.6 min and group B (n = 69) with microsleep latency >5.6 min when present. The mean sleep latency in the MWT was 14.5 ± 7.5 min in group A and 34.6 ± 7.4 min in group B (p < 0.0001). The number of microsleep episodes during each MWT trial was higher in group A than in group B. Sleep latency survival curves demonstrated different patterns of sleep latency in these groups (log‐rank test <0.0001). This finding was confirmed in a Cox proportional hazard analysis: the presence of a mean MS latency <5.6 min is associated with an increasing risk of falling asleep during the MWT (RR, 1.93; 95 CI 1.04–3.6; p = 0.03). We conclude that the detection of microsleep may help in discriminating OSA patients with and without daytime vigilance impairment.     

Daytime Sleepiness and Driving Performance in Patients with Obstructive Sleep Apnea: Comparison of the MSLT,the MWT,and a Simulated Driving Task

Study Objectives:

To test the reliability of a driving-simulation test for the objective measurement of daytime alertness compared with the Multiple Sleep Latency Test (MSLT) and with the Maintenance of Wakefulness Test (MWT), and to test the ability to drive safely, in comparison with on-road history, in the clinical setting of untreated severe obstructive sleep apnea.

Design:

N/A.

Setting:

Sleep laboratory.

Patients or Participants:

Twenty-four patients with severe obstructive sleep apnea and reported daytime sleepiness varying in severity (as measured by the Epworth Sleepiness Scale).

Interventions:

N/A.

Measurements and Results:

Patients underwent MSLT and MWT coupled with 4 sessions of driving-simulation test on 2 different days randomly distributed 1 week apart. Simulated-driving performance (in terms of lane-position variability and crash occurrence) was correlated with sleep latency on the MSLT and more significantly on the MWT, showing a predictive validity toward the detection of sleepy versus alert patients with obstructive sleep apnea. In addition, patients reporting excessive daytime sleepiness or a history of car crashes showed poorer performances on the driving simulator.

Conclusions:

A simulated driving test is a suitable tool for objective measurement of daytime alertness in patients with obstructive sleep apnea. Further studies are needed to clarify the association between simulated-driving performance and on-road crash risk of patients with sleep disordered breathing.

Citation:

Pizza F; Contardi S; Mondini S; Trentin L; Cirignotta F. Daytime sleepiness and driving performance in patients with obstructive sleep apnea: comparison of the MSLT, the MWT, and a simulated driving task. SLEEP 2009;32(3):382-391.     

Daytime variations in central nervous system activation measured by a pupillographic sleepiness test

Pupil size is regulated exclusively by the autonomic nervous system, and in darkness is proportional to the level of central sympathetic tone. Spontaneous pupillary movements, while at rest in darkness and quiet, were recorded for a period of 11 min, using infrared video pupillography. Thirteen young adults took part in a 30-h experiment lasting from 08.00 h to 14.00 h on the following day. Pupillographic testing and completion of a self-rated scale for the estimate of sleepiness were repeated every two hours. Pupillary unrest index (PUI), as a measure of pupil size instability associated with daytime sleepiness, showed the lowest values at 09.00 h, when pupil size was found to be maximal, and 23.00 h. During the course of the day, amplitude spectrum < or = 0.8 Hz and PUI showed increasing values during the afternoon hours, followed by a decrease during the evening. Daytime variations in the pupillary unrest index in healthy normal subjects were found to be positively correlated with the level of alertness. These findings are similar to the daytime variations found by the MSLT (multiple sleep latency test) in young adults.     

阻塞性睡眠呼吸暂停综合征白天嗜睡的测试及其自动监控系统的研制

目的建立一项简单客观地评价阻塞性睡眠呼吸暂停(obstructivesleepapnea,OSA)患者白天嗜睡的方法。方法先制作一套判断睡眠的自动化睡眠监控系统并用于醒觉维持试验(MWT)。10例OSA患者和5名正常人进行2次相隔约1h的MWT。记录睡眠多导图包括脑电图、眼动图和下颌肌电图。结果建立了一套判断睡眠的自动化睡眠监控系统,由自动化睡眠监控系统检测的醒觉维持时间与睡眠多导图所检测的一致。OSA患者的醒觉维持时间是(21±7)min明显小于正常人(38±2)min(P<0.01)。结论在MWT试验时,自动化睡眠监控系统可代替复杂的睡眠多导图。     

Oculomotor changes are associated to daytime sleepiness in the multiple sleep latency test

Sleep onsets in the diurnal multiple sleep latency test (MSLT), following different sleep lengths of the preceding night sleep (8, 5, 4, 3, 2, 1 h) and following the corresponding recovery nights, were considered for a study on changes of oculomotor activity during sleep onset. The study aimed to assess the individual time course in spontaneous blinks (SBs) and slow eye movements (SEMs) during the sleep onset period and also the relationship with sleep latencies in the MSLT. Group analyses compared oculomotor changes between conditions characterized by a different level of daytime sleepiness. The results show a clear inverse relation between the two oculomotor measures, with a linear SB decrease and quadratic SEM increase across the wake-sleep transition. A 150 s sample of SB and SEM activity at the start of MSLT trials correlates with individual subsequent sleep latency. Finally, mean changes in daytime sleepiness as measured by the MSLT are paralleled by coherent oculomotor changes, with a significant linear decrease of SB as sleepiness increases as a consequence of previous sleep reduction. Both individual and group results show that endogenous blinking is associated with moderate changes in daytime sleepiness.     

Weak relationships between suppression of melatonin and suppression of sleepiness/fatigue in response to light exposure

In this paper we examine the relationship between melatonin suppression and reduction of sleepiness through light by comparing three different data sets. In total 36 subjects participated in three studies and received 4 h of bright light either from midnight till 4:00 hours (experiments A and B) or from noon till 16:00 hours (experiment C). In experiment A (night-time light, partial illumination of the retina, pupil dilated) subjects were exposed to either 100 lx of ocular light on the temporal, 100 lx on the nasal part of the retina, or <10 lx of dim light on the whole retina. In experiments B (night-time light, whole retina, pupil not dilated) and C (daytime light, whole retina, pupil not dilated) subjects were exposed either to bright (5000 lx) or to dim light (<10 lx). Subjective sleepiness/fatigue and melatonin concentrations in saliva were assessed hourly in all three experiments. For experiment A, a significant suppression of melatonin due to nasal and temporal illumination of the retina was found, that was not accompanied by a detectable reduction of subjective sleepiness/fatigue. For experiment B we found a suppression of melatonin that was paralleled with a significant reduction in subjective sleepiness, but not in fatigue. During experiment C we found no melatonin suppression but a reduction of subjective sleepiness, but also no effect on fatigue. From these data we conclude that the effects of light on sleepiness/fatigue are not mediated by melatonin and that the influence of endogenous melatonin concentration on sleepiness/fatigue is restricted.     

Manipulation of core body and skin temperature improves vigilance and maintenance of wakefulness in narcolepsy

CONTEXT: Impaired vigilance and sleepiness are two majordaily complaints of patients with narcolepsy. We previously showed their sleepiness to be correlated to an abnormally regulated skin temperature, i.e., increased distal skin temperature compared with proximal skin temperature. OBJECTIVE: Our goal was to investigate a possible causal contribution of skin temperature disturbances to impairments in the ability to maintain vigilance and wakefulness in narcolepsy. DESIGN: In a modified constant routine protocol, the Psychomotor Vigilance Task (PVT) and the Maintenance of Wakefulness Test (MWT) were repeatedly assessed. Meanwhile, skin and core body temperatures were mildly manipulated within the thermoneutral range of the normal diurnal rhythm using a thermosuit and hot or cold food and drinks. SETTING: Tertiary narcolepsy referral center in a university hospital PATIENTS OR OTHER PARTICIPANTS: Eight patients (5 males) diagnosed with narcolepsy with cataplexy according to the ICSD-2 criteria (mean age +/- SD: 28.6 +/- 6.4, range 18-35 years). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): MWT sleep latency and PVT response speed. RESULTS: Compared to core cooling, core warming attenuated the typical decline in PVT response speed with increasing time-on-task by 25% (P = 0.02). Compared to distal skin warming, distal skin cooling increased the time that the patients were able to maintain wakefulness by 24% (distal warming: 1.88 min. vs. distal warming: 2.34 min.; P < 0.01). CONCLUSIONS: Core body and skin temperatures causally affect vigilance and sleepiness in narcolepsy. This could lead to future practical applications.     

Autonomic markers of arousal during sleep in patients undergoing investigation for obstructive sleep apnoea, their relationship to EEG arousals, respiratory events and subjective sleepiness

Estimating the degree of sleep fragmentation is an important part of a respiratory sleep study and is conventionally measured using EEG micro arousals or is inferred indirectly from respiratory abnormalities such as apnoeas and desaturations. There is a need for less labour-intensive measures of sleep fragmentation, and transient rises in blood pressure and heart rate may fulfil this role. Forty unselected sleep clinic referrals undergoing investigation for possible obstructive sleep apnoea (OSA) were studied with one night of polysomnography. Three conventional indices of sleep fragmentation (EEG micro arousals, apnoea/hypopnoea index (AHI) and oxygen saturation dip rate (SaO₂ dips)) and two autonomic indices (heart rate and blood pressure rises) have been compared. Correlations between these five indices ranged from r=0.38 to r=0.73. Of the two autonomic indices, the correlations for blood pressure rises with SaO₂ dips and EEG micro arousals were stronger (r=0.71 and r=0.65, respectively) than those for heart rate rises (0.55 and 0.51). All indices of sleep fragmentation, apart from heart rate rises, were similar in their correlation with subjective sleepiness (r-values 0.21–0.36). Arousals implied from blood pressure rises (using pulse transit time) can be measured easily, are objective, and appear no worse at predicting subjective sleepiness than either EEG micro arousals or AHI. They may therefore provide a useful alternative to manual scoring of micro arousals from the EEG as an index of sleep fragmentation in sleep clinic patients undergoing investigation for possible OSA.     

Impact of continuous positive airway pressure (CPAP) on quality of life in patients with obstructive sleep apnea (OSA)

Obstructive sleep apnea is a chronic illness with increasing prevalence. In addition to associated cardiovascular comorbidities, obstructive sleep apnea syndrome has been linked to poor quality of life, occupational accidents, and motor vehicle crashes secondary to excessive daytime sleepiness. Although continuous positive airway pressure is the gold standard for sleep apnea treatment, its effects on quality of life are not well defined. In the current study we investigated the effects of treatment on quality of life using the data from the Apnea Positive Pressure Long‐term Efficacy Study (APPLES), a randomized controlled trial of continuous positive airway pressure (CPAP) versus sham CPAP. The Calgary Sleep Apnea Quality of Life Index (SAQLI) was used to assess quality of life. Overall we found no significant improvement in quality of life among sleep apnea patients after CPAP treatment. However, after stratifying by OSA severity, it was found that long‐term improvement in quality of life might occur with the use of CPAP in people with severe and possibly moderate sleep apnea, and no demonstrable improvement in quality of life was noted among participants with mild obstructive sleep apnea.     

Definition of excessive daytime sleepiness in the general population: Feeling sleepy relates better to sleep‐related symptoms and quality of life than the Epworth Sleepiness Scale score. Results from an epidemiological study

Many different subjective tools are being used to measure excessive daytime sleepiness (EDS) but the most widely used is the Epworth Sleepiness Scale (ESS). However, it is unclear if using the ESS is adequate on its own when assessing EDS. The aim of this study was to estimate the characteristics and prevalence of EDS using the ESS and the Basic Nordic Sleep Questionnaire (BNSQ) in general population samples. Participants aged 40 years and older answered questions about sleepiness, health, sleep‐related symptoms and quality of life. Two groups were defined as suffering from EDS: those who scored >10 on the ESS (with increased risk of dozing off) and those reporting feeling sleepy during the day ≥3 times per week on the BNSQ. In total, 1,338 subjects (53% male, 74.1% response rate) participated, 13.1% reported an increased risk of dozing off, 23.2% reported feeling sleepy and 6.4% reported both. The prevalence of restless leg syndrome, nocturnal gastroesophageal reflux, difficulties initiating and maintaining sleep and nocturnal sweating was higher among subjects reporting feeling sleepy compared to non‐sleepy subjects. Also, subjects reporting feeling sleepy had poorer quality of life and reported more often feeling unrested during the day than non‐sleepy subjects. However, subjects reporting increased risk of dozing off (ESS > 10) without feeling sleepy had a similar symptom profile as the non‐sleepy subjects. Therefore, reporting only risk of dozing off without feeling sleepy may not reflect problematic sleepiness and more instruments in addition to ESS are needed when evaluating daytime sleepiness.