Excessive Daytime Sleepiness Group Research Articles

Delayed sleep/wake rhythm and excessive daytime sleepiness correlate with decreased daytime brain activity during cognitive task in university students

Insufficient sleep and irregular sleep/wake rhythm are common problems among university students. We investigated the effect of sleep/wake rhythm and excessive daytime sleepiness (EDS) on the cortical oxygenation as measured by near-infrared spectroscopy (NIRS) and cognitive performance in university students. Peak- and integral values by a word fluency task were measured with NIRS. EDS was evaluated by the Epworth sleepiness scale (ESS), and performance function was evaluated using N-back task. Peak cerebral oxygenation was significantly correlated with ESS, bedtime, wake-up time, and median time of sleep. Accuracy on 2-back task was significantly correlated with integral value. Peak- and integral values were significantly lower, and bedtime and median time of sleep were significantly delayed in the EDS group than in the non-EDS group. EDS accompanied by delayed sleep/wake rhythm and short sleep duration may play an important role in decreasing daytime brain activity and cognitive performance.

Sleep Duration and Excessive Daytime Sleepiness Are Associated With Incidence of Disability in Community-Dwelling Older Adults

ObjectiveAlthough sleep disturbances are associated with disability among older adults, no longitudinal study has examined the impact of sleep assessed based on both sleep quality and quantity on incident disability. This study examined whether sleep duration and excessive daytime sleepiness were associated with incidence of disability in community-dwelling older adults. MethodsA total of 4756 older adults (53.3% women, mean age 71.9 years) met the entry criteria for this study. We measured monthly incident disability, defined as the onset of being certified for personal support or care as required by Japanese public long-term care insurance during the preceding 24 months. Sleep duration, excessive daytime sleepiness (EDS), and demographic factors were assessed at baseline. Cox's proportional hazard regression analysis estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of incidence of disability according to the 3 categories of sleep duration (short: ≤6.0 hours, mid: 6.1 to 8.9 hours, long: ≥9.0 hours), and we used mid duration sleepers as the reference group. ResultsLong sleep duration (HR 1.43, 95% CI 1.04–1.97) and presence of EDS (HR 1.41, 95% CI 1.01–1.98) were associated with higher rates of incident disability. Furthermore, a combination of sleep duration and EDS was associated with a higher rate of incident disability than the mid and no EDS group (HR 2.25, 95% CI 1.36–3.70). ConclusionLong sleep duration and EDS affected the incident of disability; thus, older adults with both sleep patterns may require an intervention to alter their sleep habit.

An analysis of clinical characteristics and factors in Parkinson's disease patients with excessive daytime sleepiness

To explore the clinical characteristics and prognostic factors in patients with Parkinson's disease (PD) and excessive daytime sleepiness (EDS) and to identify whether EDS could influence the sleep architecture and sleep apnea-related parameters. A total of 130 PD patients were eligible and enrolled in the study.By the Epworth sleepiness scale (ESS), patients were divided into the EDS group (ESS≥10) with 61 patients and the non-EDS group (ESS<10) with 69 patients.All underwent a video-polysomnography (PSG). Clinical characteristics were mainly evaluated by the unified Parkinson's disease rating scale (UPDRS) and the Hoehn-Yahr(H-Y)stage.while other related scales were applied for evaluating depression, cognitive function, quality of sleep and quality of life. A total of 61 patients (46.92%) were diagnosed as EDS (ESS≥10). Compared to the non-EDS group, the EDS group had significantly higher score of HAMD, UPDRSⅠand UPDRSⅡ, and significantly lower score of MoCA and PDQ (all P<0.05). Non-conditional logistic regression analysis showed that the scores of HAMD and UPDRSⅠ were the main prognostic factors for EDS.Significantly decreased sleep latency (SL) was found in the EDS group by PSG (P=0.008). The score of ESS was showed to be correlated with the scores of HAMD, MoCA, UPDRSⅠ, UPDRSⅡ, PDQ and SL. PD patients with EDS have more severe depression and cognitive dysfunction and worse quality of life.Sleep structure is altered in those patients with decreased sleep latency.Mental status is closely associated with EDS, but not sleep apnea.

Excessive daytime sleepiness in adults with possible attention deficit/hyperactivity disorder (ADHD): a web-based cross-sectional study

ObjectivesArousal dysregulation has been speculated to be involved in the pathological mechanism of attention deficit/hyperactivity disorder (ADHD). However, there has been no epidemiological study assessing the real condition of excessive daytime sleepiness (EDS) in adults with ADHD. This study investigated the prevalence of EDS and the relationship between sleepiness and ADHD symptoms in adults with possible ADHD. MethodsAn observational, cross-sectional, web-based study was performed. Participants were 9822 Japanese adults aged 20–69 years who completed an Internet-based questionnaire that assessed ADHD symptoms, autistic traits, depressive symptoms, chronotype, sleepiness, and sleep disturbances. ResultsParticipants with possible ADHD were more likely than non-ADHD participants to have an evening chronotype and experience depressive symptoms, sleepiness, and sleep disturbances. The rates of having moderate and severe sleepiness in the possible ADHD group were higher than those in the non-ADHD group. Hierarchical logistic regression analyses revealed that the presence of ADHD symptoms was independently associated with EDS even after adjusting for factors related to the presence of sleepiness. When examining inattention and hyperactivity scores among participants with possible ADHD, the inattention score was significantly higher in the severe EDS group compared with the moderate and non-EDS groups. ConclusionsEDS was relatively common in adults with possible ADHD. ADHD symptoms, especially inattentiveness, were associated with the formation of EDS in this population.

Characterization of Daytime Sleepiness by Time–Frequency Measures of EEG Signals

Excessive daytime sleepiness (EDS) is one of the main symptoms of several sleep-related disorders with a great impact on patient lives. While many studies have been carried out in order to assess daytime sleepiness, automatic EDS detection still remains an open problem. In this work, a detection approach based on the time–frequency analysis of electroencephalography (EEG) signals is proposed. Multichannel EEG signals were recorded during five maintenance of wakefulness (MWT) and multiple sleep latency tests alternated throughout the day from patients suffering from sleep-disordered breathing. A group of 20 patients with EDS was compared with a group of 20 patients without daytime sleepiness (WDS) by analyzing 60-s EEG windows in the waking state. Measures obtained from the Choi–Williams distribution (CWD) and the cross-CWD were calculated in the EEG frequency bands δ (0.1–4 Hz), θ (4–8 Hz), α (8–12 Hz), β (12–30 Hz), and total band (TB, 0.1–45 Hz). Statistical differences between EDS and WDS groups were found in the δ and θ bands during MWT events (p < 0.0001). The results show that the EDS group presented more power in the θ band, while the WDS group presented higher spectral and cross-spectral entropy in the frontal zone in the δ band. In general, CWD and cross-CWD measures yielded sensitivities and specificities of above 80 %. The area under the receiver operating characteristic curve was above 0.85 for classifying EDS and WDS patients.

The relationship between excessive daytime sleepiness and metabolic syndrome in severe obstructive sleep apnea syndrome.

Excessive daytime sleepiness (EDS), which is commonly considered a cardinal sign of obstructive sleep apnea (OSA), may lead to an increased rate of metabolic syndrome (MetS), and be an independent risk factor for cardiovascular morbidity and mortality. The aim of this cross-sectional study was to examine the role of EDS in MetS and its components by researching severe OSA patients. The records of 175 consecutive patients who underwent standard polysomnography and diagnosed severe OSA were included. Subjective daytime sleepiness was assessed using the Epworth sleepiness scale (ESS). Fasting glucose, lipids, insulin and polysomnography parameters were measured. A metabolic score was counted as the total number of the positive diagnostic criteria of MetS for each subject, which indicated the level of metabolic disorder. The prevalence of central obesity, hypertriglyceridemia, low high density lipoprotein-cholesterol and MetS (78.2% vs 28.6%) was significantly higher among EDS group compared with control group. Compared with non-EDS patients, patients with EDS showed significantly higher metabolic score (3.22 ± 0.94 vs 1.96 ± 1.06). After adjustment for confounders, ESS score, log insulin and age significantly predicted the metabolic score (β = 0.567, P = 0.000; β = 0.197, P = 0.001 and β = 0.118, P = 0.048, respectively). EDS was independently correlated with the sum of metabolic components in severe OSA patients. Our study suggested that EDS might be a potentially useful clinical marker to identify patients with severe OSA at risk of MetS.

Mutual informationmeasuresapplied to EEG signals for sleepinesscharacterization

Excessive daytime sleepiness (EDS) is one of the main symptoms of several sleep related disorders with a great impact on the patient lives. While many studies have been carried out in order to assess daytime sleepiness, the automatic EDS detection still remains an open problem. In this work, a novel approach to this issue based on non-linear dynamical analysis of EEG signal was proposed. Multichannel EEG signals were recorded during five maintenance of wakefulness (MWT) and multiple sleep latency (MSLT) tests alternated throughout the day from patients suffering from sleep disordered breathing. A group of 20 patients with excessive daytime sleepiness (EDS) was compared with a group of 20 patients without daytime sleepiness (WDS), by analyzing 60-s EEG windows in waking state. Measures obtained from cross-mutual information function (CMIF) and auto-mutual-information function (AMIF) were calculated in the EEG. These functions permitted a quantification of the complexity properties of the EEG signal and the non-linear couplings between different zones of the scalp. Statistical differences between EDS and WDS groups were found in β band during MSLT events (p-value < 0.0001). WDS group presented more complexity than EDS in the occipital zone, while a stronger nonlinear coupling between occipital and frontal zones was detected in EDS patients than in WDS. The AMIF and CMIF measures yielded sensitivity and specificity above 80% and AUC of ROC above 0.85 in classifying EDS and WDS patients.

Correntropy measures to detect daytime sleepiness from EEG signals

Excessive daytime sleepiness (EDS) is one of the main symptoms of several sleep related disorders and has a great impact on patients’ lives. While many studies have been carried out in order to assess daytime sleepiness, automatic EDS detection still remains an open problem. In this work, a novel approach to this issue based on correntropy function analysis of EEG signals was proposed in order to detect patients suffering from EDS. Multichannel EEG signals were recorded during five Maintenance of Wakefulness Tests (MWT) and Multiple Sleep Latency Tests (MSLT) alternated throughout the day for patients suffering from sleep disordered breathing (SDB). A group of 20 patients with EDS was compared with a group of 20 patients without daytime sleepiness (WDS), by analyzing 60 s EEG windows in a waking state. Measures obtained from the cross-correntropy function (CCORR) and auto-correntropy function (ACORR) were calculated in the EEG frequency bands: δ, 0.1–4 Hz; θ, 4–8 Hz; α, 8–12 Hz; β, 12–30 Hz; total band TB, 0.1–45 Hz. These functions permitted the quantification of complex signal properties and the non-linear couplings between different areas of the scalp. Statistical differences between EDS and WDS groups were mainly found in the β band during MSLT events (p-value < 0.0001). The WDS group presented more complexity in the occipital zone than the EDS group, while a stronger nonlinear coupling between the occipital and frontal regions was detected in EDS patients than in the WDS group. At best, ACORR and CCORR measures yielded sensitivity and specificity above 80% and the area under ROC curve (AUC) was above 0.85 in classifying EDS and WDS patients. These performances represent an improvement with respect to classical EEG indices applied in the same database (sensitivity and specificity were never above 80% and AUC was under 0.75).

The different clinical faces of obstructive sleep apnoea: a cluster analysis.

Although commonly observed in clinical practice, the heterogeneity of obstructive sleep apnoea (OSA) clinical presentation has not been formally characterised. This study was the first to apply cluster analysis to identify subtypes of patients with OSA who experience distinct combinations of symptoms and comorbidities. An analysis of baseline data from the Icelandic Sleep Apnoea Cohort (822 patients with newly diagnosed moderate-to-severe OSA) was performed. Three distinct clusters were identified. They were classified as the "disturbed sleep group" (cluster 1), "minimally symptomatic group" (cluster 2) and "excessive daytime sleepiness group" (cluster 3), consisting of 32.7%, 24.7% and 42.6% of the entire cohort, respectively. The probabilities of having comorbid hypertension and cardiovascular disease were highest in cluster 2 but lowest in cluster 3. The clusters did not differ significantly in terms of sex, body mass index or apnoea-hypopnoea index. Patients with OSA have different patterns of clinical presentation, which need to be communicated to both the lay public and the professional community with the goal of facilitating care-seeking and early identification of OSA. Identifying distinct clinical profiles of OSA creates a foundation for offering more personalised therapies in the future.

Relationship of Heart Rate Variability to Sleepiness in Patients with Obstructive Sleep Apnea with and without Heart Failure

Many patients with severe obstructive sleep apnea (OSA) do not complain of excessive daytime sleepiness (EDS), possibly due to increased sympathetic nervous activity (SNA) and accompanying heightened alertness. We hypothesized that in patients with OSA, those without subjective EDS (Epworth Sleepiness Scale, ESS score < 11) would have higher very low frequency (VLF) heart rate variability (HRV) during sleep, reflecting greater sympathetic heart rate modulation than patients with an ESS score ≥ 11. Patients with severe OSA (AHI ≥ 30: 26 with and 65 without heart failure) were divided into those with and without EDS. Heart rate (HR) signals were acquired in stage 2 sleep during periods of recurrent apneas and hypopneas and submitted to coarse graining spectral analysis, which extracts harmonic, neurally mediated contributions to HRV from total spectral power. Because the apnea-hyperpnea cycle entrains muscle SNA at VLF (0 to 0.04 Hz), VLF power was our principal between-group comparison. Subjects without EDS had higher harmonic VLF power (944 ± 839 vs 447 ± 461 msec(2), p = 0.003) than those with EDS, irrespective of the presence or absence of heart failure (1218 ± 944 vs 426 ± 299 msec(2), p = 0.043, and 1029 ± 873 vs 503 ± 533 msec(2), p = 0.003, respectively). ESS scores correlated inversely with VLF power in all (r = -0.294, p = 0.005) and in heart failure subjects (r = -0.468, p = 0.016). Patients with severe OSA but without EDS have higher VLF-HRV than those with EDS. This finding suggests that patients with severe OSA but without EDS have greater sympathetic modulation of HRV than those with EDS that may reflect elevated adrenergically mediated alertness. Taranto Montemurro L; Floras JS; Picton P; Kasai T; Alshaer H; Gabriel JM; Bradley TD. Relationship of heart rate variability to sleepiness in patients with obstructive sleep apnea with and without heart failure.

The Association between the Phenotype of Excessive Daytime Sleepiness and Blood Pressure in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome

Objective Investigate the clinical features and the blood pressure (BP) pattern of the phenotype of excessive daytime sleepiness (EDS) in OSAHS.Methods A total of 508 Chinese adults with suspected OSAHS were referred to our sleep laboratory from October 2009 to May 2012. On the same night of polysomnography (PSG), the levels of blood pressure were measured before sleeping (bedtime BP) and immediately after waking up in the next morning (morning BP). EDS was recognized as Epworth Sleepiness Scale (ESS)≥9. Subjects were classified into four groups based on the apnea-hypopnea index (AHI) from PSG as follows: control (simple snoring) group (control, n=104) with AHI<5; mild group (mild, n=89) with AHI≥5 and <15; moderate group (moderate, n=70) with AHI≥15 and<30; and severe group (severe, n=245) with AHI ≥30. The differences and correlations between BP and PSG parameters in EDS and non-EDS group of OSAHS patients were analyzed.Results In all subjects, ESS was positively correlated with morning diastolic blood pressure (DBP), Mean arterial pressure (MAP) and bedtime DBP (r=0.144, 0.102 and 0.114, respectively, each P value<0.05). In OSAHS patients, ESS was only positively correlated with morning DBP (r=0.137, P<0.05). OSAHS patients with EDS phenotype were younger and were more likely to have the symptom of waking up feeling tired (36.1% vs. 23.2%, p=0.023), who had lower MSaO2, longer SIT90 (the ratio of time of SpO2 below 90% in total sleep time) and higher DBP (bedtime as well as morning). In patients with AHI≥15, ESS was correlated positively with both bedtime and morning DBP after controlling the confounding effects of age, sex, BMI, AHI and nadir nocturnal oxygen saturation( r=0.126,0.143, respectively, both P values<0.05). And in OSAHS patients of EDS phenotype, the bedtime DBP, bedtime MAP, morning DBP, and morning MAP were 3~5 mm Hg higher than that in patients of non-EDS phenotype(P<0.05). In the moderate and severe OSAHS group, patients with EDS phenotype were younger and had a lower mean blood oxygen saturation (MSaO2), longer time of SpO2 below 90% and higher SIT90 than patients with non-EDS phenotype (P<0.05). In hypertensive OSAHS patients, patients with EDS were also younger and had higher micro-arousal index (MiI), as well as higher morning DBP, morning MAP and bedtime DBP than that in non-EDS group (P<0.05).Conclusions EDS in OSAHS patients is a special phenotype, which was characterized by younger age, higher DBP and more severe hypoxic load. This feature is mainly manifested in moderate and severe OSAHS patients. It is very important to identify the phenotype of EDS in patients with OSAHS, who may meet more benefits from effective treatment of OSAHS by correcting the intermittent nocturnal hypoxia and sleep fragmentation.

Double jeopardy: the influence of excessive daytime sleepiness and impaired cognition on health‐related quality of life in adults with heart failure

To determine how excessive daytime sleepiness (EDS) and impaired cognition contribute to health-related quality of life (HRQL) in heart failure (HF). Adults with chronic HF were enrolled into a prospective cohort study. Data were obtained from 280 subjects enrolled from three sites in the northeastern USA; 242 completed the 6-month study. At baseline, cohorts with and without EDS were identified using the Epworth Sleepiness Scale. Each EDS group was further subdivided into those with and without impaired cognition using a battery of five neuropsychological tests. Two disease-specific measures, the Kansas City Cardiomyopathy Questionnaire (KCCQ) and the Functional Outcomes of Sleep Questionnaire (FOSQ), were used to measure HRQL. General linear modelling of square-transformed variables was used to test the hypothesis that cohort membership was a significant predictor of HRQL. At 6 months the remaining sample was 62.5 [standard deviation (SD) 12] years old, mostly male (63%), white (65%), and functionally compromised [72% New York Heart Association (NYHA) class III/IV]. The cohort with both EDS and impaired cognition had the lowest KCCQ overall summary score (60.5 ± 22.5) compared with the cohort without EDS or impaired cognition (74.6 ± 17.4, P ≤ 0.001). A similar effect was seen on the FOSQ (16.0 ± 2.8 vs. 18.5 ± 2.2, P < 0.001). Impaired cognition alone did not explain poor HRQL, but the addition of EDS poses a significant risk for poor HRQL. Interventions designed to influence EDS may improve HRQL in this population.

Factors Associated with Excessive Daytime Sleepiness in Obstructive Sleep Apnea Syndrome under CPAP Treatment

The purpose of this study was to assess factors associated with subjective sleep evaluation, chiefly excessive daytime sleepiness (EDS) in obstructive sleep apnea syndrome (OSAS) adult outpatients under continuous positive airway pressure (CPAP) treatment. One thousand and forty-eight OSAS outpatients (mean age: 51.4% male: 90.5%) who were treated by CPAP were consecutively collected. Age, sex, CPAP compliance (CPAP usage as their device of nights with application-time of at least 4 hours per night objectively; %usage ≥ 4 h/d), and Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J) of the patients showing EDS (Japanese version of the Epworth Sleepiness Scale; JESS ≥ 11) were compared cross-sectionally with those of the patients who did not show EDS (JESS < 11). Nineteen point two % of all patients showed EDS subjectively. Two hundred one patients were classified to an EDS(+) group and an 847 patients were classified to EDS(–) group. Age and global PSQI-J scores were significantly different between the two groups. Logistic regression showed that EDS was significantly associated with global PSQI-J scores, but not with age. Among PSQI-J components, overall sleep quality, duration of sleep, sleep disturbance, and day dysfunction due to sleepiness were significantly higher in the EDS(+) group. Especially, 19.4% of patient in the EDS(+) group reported actual sleep time during the past month to be less than 5 hours/day. Although functional relationship should be further evaluated, insufficient sleep is the main factor associated with EDS in the OSAS patients under CPAP treatment.

Relationship between excessive daytime sleepiness and oxygen saturation in obstructive sleep apnea-hypopnea syndrome

To investigate polysomnographic determinants of excessive daytime sleepiness (EDS) and potential relationship in Chinese patients with obstructive sleep apnea-hypopnea syndrome (OSAS). A total of 410 patients with obstructive sleep apnea-hypopnea syndrome were analyzed retrospectively who were obtained in Sleep medicine center of West China hospital from January to April in 2010. All of the patients with an apnea-hypopnea index (AHI) greater than 5 h(-1) were evaluated using the Epworth Sleepiness Scale (ESS) and sleep disorders questionnaire. The patients who ESS score was more than 10 were defined as EDS; otherwise, the other was considered to without EDS. A total of 176 patients with EDS (ESS: 15 ± 3) and 234 without EDS (ESS: 6 ± 3) were studied. Patients with EDS were slightly higher BMI (28 ± 4 vs 26 ± 4) and shorter REM sleep latency (99 ± 65 vs 125 ± 81) than patients without EDS. Furthermore, there were significant difference in awake SaO2, AHI, minimum SaO2, oxygen desaturation index and arousal index between EDS group were No-EDS group (P < 0.001). There was a significant difference in waking SaO2 of severe OSAS between both groups. Long-term chronic hypoxia already exists in severe OSAS patients with prominent sleepiness. Waking SaO2 may play a role as a predictor in evaluation and diagnosis in patients with OSAS.

Autonomic Arousals in Sleep Related Breathing Disorders: A Link Between Daytime Somnolence and Hypertension?

WE HAVE READ WITH EXTREME INTEREST THE RECENT ARTICLE PUBLISHED ON YOUR JOURNAL BY KAPUR ET AL.1 THE FINDINGS OF THIS STUDY EMPHASIZE the important role of daytime sleepiness in determining the risk of hypertension in patients with sleep-related breathing disorders. In particular, in Figure 1 the authors clearly show that only in patients with daytime somnolence there is an increase in the risk of hypertension, in parallel with the increase in apnea-hypopnea index. The important and clinically relevant contribution carried by this excellent study, is the identification of daytime sleepy patients as a group at greater risk of cardiovascular events. However, this study was not designed to investigate the mechanisms responsible for the association between sleepiness and hypertension, an important issue which thus remains unresolved. We have hypothesized that excessive daytime sleepiness (EDS) in patients with sleep related breathing disorders may be associated with subcortical arousals. Apnea-related autonomic arousals may not produce detectable EEG changes. However, since they involve brainstem neurons controlling both sleep/vigilance and cardiovascular regulation, they may simultaneously trigger daytime somnolence and appreciable changes in cardiac autonomic regulation. Therefore alterations in cardiac autonomic control might be considered as markers of the occurrence of autonomic arousals in patients with sleep related breathing disorders. These alterations can be easily assessed by estimating changes in spontaneous baroreflex sensitivity2 or in specific indexes of heart rate variability3 from polysomnographic recordings. Shortly before Kapur et al reported their findings, we demonstrated the association between EDS and impaired autonomic cardiac modulation in a study4 published online in May 2008. To test our hypothesis we applied a multiple latency sleep test to quantify EDS in normotensive patients with sleep related breathing disorders ranging from snoring to obstructive apnea; these patients then underwent a complete overnight polysomnography associated with non-invasive beat-by-beat blood pressure monitoring. We found that patients with and without EDS had similar values of apnea-hypopnea index, similar sleep characteristics, and also similar overnight values of blood pressure (hypertension was among the exclusion criteria in our study). However, patients with EDS showed a significantly lower baroreflex sensitivity (known to be potentially linked to development of hypertension), and a higher ratio of the low-frequency to high-frequency powers of heart rate variability (an acknowledged indirect indication of changes in cardiac sympatho/vagal balance towards a predominant sympathetic modulation). In a successive analysis we confirmed these results also after excluding obese patients (BMI ≥30 kg/m2) in the EDS group, in order to completely exclude the obese hypoventilation syndrome as a possible cause of somnolence.5 Our findings demonstrate an association between daytime sleepiness and impaired autonomic cardiac modulation even in subjects who have not yet developed overt hypertension (preclinical stage), but who are at high risk for its future development. Our results may thus help understanding the mechanisms responsible for the association between daytime sleepiness and hypertension demonstrated by Kapur et al.1 Our hypothesis is that autonomic arousals, which may occur in some of the patients suffering from sleep related breathing disorders, are associated with both daytime sleepiness and alterations of cardiac autonomic modulation. These changes in autonomic cardiovascular regulation, on top of the well known alterations in chemoreflex activity, in mechanics of ventilation and in sleep structure characterizing obstructive sleep apnea, could explain why daytime sleepiness is associated with a higher risk of developing arterial hypertension. The work by Kapur et al1 provides data which are clearly supporting our hypothesis, and which unequivocally indicate the importance of taking the level of daytime somnolence into account to prevent cardiovascular events in patients with sleep related breathing disorders.

The Psychosocial Problems of Children With Narcolepsy and Those With Excessive Daytime Sleepiness of Uncertain Origin

Narcolepsy is a predominantly rapid eye movement sleep disorder with onset usually in the second decade but often in earlier childhood. Classically it is characterized by combinations of excessive sleepiness especially sleep attacks, cataplexy, hypnagogic hallucinations, and sleep paralysis. The psychosocial effects of this lifelong condition are not well documented, especially in children. This study aims to describe the psychosocial profile of a large group of children with narcolepsy compared with other excessively sleepy children and controls. We used an international cross-sectional questionnaire survey of children aged from 4 to 18 years who had received from a physician a diagnosis of narcolepsy compared with age- and gender-matched controls. Assessments were made of behavior, mood, quality of life, and educational aspects. Recruited children were separated into those who met conventional criteria for narcolepsy (n = 42) and those whose primary complaint was excessive daytime sleepiness without definite additional features of narcolepsy (excessive daytime sleepiness group; n = 18). Compared with controls, children with narcolepsy and also those with excessive daytime sleepiness alone showed significantly higher rates of behavioral problems and depression. Again, to a significant extent, their quality of life was poorer and they had more educational problems. The children with narcolepsy and the excessive daytime sleepiness group were indistinguishable from each other on these measures. A range of psychosocial problems can be identified in children with narcolepsy. The origins of these problems are unclear. The similar profiles of difficulties in the narcolepsy and excessive daytime sleepiness groups suggest that excessive sleepiness is the main cause. Clinicians and others responsible for the care of such children need to be mindful of the importance of early detection, intervention, and, ideally, the prevention of these problems.

Excessive Daytime Sleepiness in Parkinson Disease: A SPECT Study

The underlying pathologic mechanism of excessive daytime sleepiness (EDS) in Parkinson disease and the relative contributions of brain function to this process are poorly understood. We compared brain perfusion images between patients with Parkinson disease and EDS and those without EDS using n-isopropyl-p-1231 iodoamphetamine single photon emission computed tomography. Clinical study. Sumitomo Hospital. Thirteen patients with Parkinson disease with EDS (EDS group) and 27 patients with Parkinson disease without EDS (no-EDS group) were studied. Whether or not each case had EDS was determined according to the response to the Epworth Sleepiness Scale: patients with an Epworth Sleepiness Scale score > or = 10 were included in the EDS group, and patients with an Epworth Sleepiness Scale score < or = 9 were included in the no-EDS group. There were significant hypoperfusions in the left parietal and temporal association cortex in the EDS group. In the multivariable logistic regression model, attention and decreased regional cerebral blood flow of the left parietal association cortex and right caudate and increased regional cerebral blood flow of the right thalamus were the independent and significant factors. The cortical hypofunction relative to hyperfunction of the brain stem may relate to EDS in Parkinson disease. This is the first imaging study about EDS in Parkinson disease, and further studies are required.

P300 Latency: Abnormal in Sleep Apnea with Somnolence and Idiopathic Hypersomnia, but Normal in Narcolepsy

To evaluate cognitive abnormalities in excessive daytime sleepiness (EDS) using cognitive evoked potentials (P300), and to evaluate if P300 measures differentiate among disorders of EDS, a series of EDS subjects were administered a polysomnogram, auditory and visual P300 testing using 31 scalp electrodes, and a multiple sleep latency test. P300 variables were compared with those of normal subjects. Forty normal subjects ages 16 to 65 years, and 69 EDS patients ages 16 to 65 years were used. Of these, 39 had profound obstructive sleep apnea (OSA, Respiratory Disturbance Index or RDI > 80/h sleep) with severe somnolence (Mean Sleep Latency < 5 min). Twenty-two had idiopathic hypersomnia (IH). Eight had narcolepsy. The normals and the three EDS groups did not differ in age. IH and profound OSA patients had longer visual P300 latency than normals or narcolepsy patients (p < 0.05). (p < 0.05). IH and profound OSA patients had longer auditory P300 latency than normals. They had smaller auditory P300 amplitude than narcolepsy patients. There were visual P300 latency topographic differences between normals and profound OSA patients. In conclusion, IH and profound OSA patients show cognitive evoked potential evidence of cognitive dysfunction. Narcolepsy patients do not show such evidence. Visual P300 latency differentiates among disorders of EDS.