BACKGROUND:Until now, studies about body position and nocturnal breathing abnormalities have been restricted to comparing supine versus lateral positions.OBJECTIVES:In this retrospective study, we systematically evaluated the effect of body position on nocturnal breathing in 105 patients with a sleep apnea hypopnea syndrome (SAHS).METHODS:All the patients had an apnea hypopnea index > 10/h, as judged from polysomnography performed in the sleep laboratory. A thoracic sensor allowed to detect nine distinct body positions: supine (S), supine right (SR), right (R), prone right (PR), prone (P), prone left (PL), left (L), supine left (SL) and sitting upward (UP). Respiratory variables (number of obstructive, central and mixed apneas, of hypopneas and of desaturations, all expressed as an index per hour of total sleep time) were evaluated versus the body positions, using the non-parametric Kruskal-Wallis H method. Pairwise comparisons were performed using Mann-Whitney U tests.RESULTS:Most of the total sleep time (45%) was spent supine. A significant effect of body position was found for all the respiratory variables. Breathing was better in the intermediate SR and SL positions than S, and also better in PR and PL positions than, respectively, R and L. All the respiratory variables gradually improved when gradualling moving from the S to the P position.CONCLUSIONS:A nine position sensor, able to define intermediate positions in addition to the basic cardinal positions, is useful in the sleep laboratory. Using such a sensor, we found in SAHS patients that nocturnal breathing improves as a continuum from the S to the P position.

Objective: The lack of distinction in the clinical use of terms like fatigue and sleepiness is an important issue. While both fatigue and sleepiness can potentially be associated with nonrestorative sleep (NRS) complaints, their relationships are still poorly described. We propose to use Rasch analysis-based methods to study the interrelations of fatigue, sleepiness and NRS. Methods: 150 subjects (mean age = 39.3 years, range = 18–65) from a community sample underwent a structured computer-assisted web interview. We assessed demographic data, sleep habits, and subjective fatigue with the Fatigue Severity Scale (FSS), global and situational sleepiness with the Epworth Sleepiness (ESS) and the Stanford Sleepiness Scales, respectively, and affective symptoms with the Hospital Anxiety and Depression Scale. Dimensionality, measurement invariance and common person equating were investigated to study the FSS, ESS and their relations to NRS. Results: NRS was linked to shorter habitual sleep duration and to higher scores on psychometric scales. Both sleepiness and daytime fatigue were positively correlated to each other and to the intensity of affective symptoms. Rasch analyses showed both the ESS and FSS to measure unidimensional concepts of sleepiness and fatigue, respectively. In contrast to the FSS, the ESS only showed partial invariance to an NRS complaint. Common person equating suggests that, despite similar Rasch-derived agreeability scores, fatigue and sleepiness (as measured by the FSS and ESS) nevertheless designate distinct constructs. Conclusion: NRS complaints can simultaneously present with higher daytime fatigue and sleepiness levels but the associative relationships between fatigue and sleepiness remain relatively unaffected by NRS. Although participants might not present adequate differentiation, fatigue and sleepiness seem to relate to different underlying concepts.

The status of chronic fatigue syndrome (CFS) is still under debate. Mainstream views still often consider it as an undetected primary sleep disorder or as the psychosomatic expression of a related anxiety or depression syndrome. Both primary sleep disorder and CFS are often related to unrefreshing sleep and affective daytime symptoms. The present study compares nonrapid eye movement sleep distribution between patients with a primary sleep disorder and "pure" CFS patients without sleep or mood disorders. Intensity measures of affective symptoms are also analyzed. Sleep variables of 32 pure CFS (mean age, 41.9 +/- 8.7 years; 25 women), 30 Sleep Apnea Hypopnea Syndrome patients (mean age, 43.7 +/- 6.7 years; 13 women), and 14 healthy controls (mean age, 40.2 +/- 7.6 years; 9 women) were compared. Related affective symptoms were assessed using the self-reported Zung anxiety and depression scales. The study confirms previous reports on increased slow-wave sleep in CFS patients. Both patient groups showed similar sleep duration and efficiency. Sleep efficiency was lower in both patient groups compared with controls. CFS patients showed a higher microarousal index than controls. Anxiety, but not depression symptoms were more intense in the CFS group. The distribution of nonrapid eye movement sleep in CFS differs sizeably from what can be observed in a primary sleep disorder.

It is presently unclear whether chronic fatigue syndrome (CFS) patients exhibit daytime sleepiness in addition to fatigue. Both, fatigue, such as that seen in CFS patients, and excessive daytime sleepiness, such as in sleep apnea-hypopnea syndrome (SAHS), remain poorly understood. Both daytime conditions are generally related to unrefreshing sleep and show affective symptoms. This study's objective was to contribute to the understanding of the relationship between fatigue and sleepiness in CFS patients not co-morbid for primary sleep or psychiatric disorders. We compared 16 untreated CFS patients (mean age 32.8, all females) with 13 untreated SAHS (mean age 47.7, all females) patients and 12 healthy controls (mean age 32.2, all females). Objective sleepiness was measured using multiple sleep latency tests (MSLT). Subjective sleepiness and fatigue were assessed with the Epworth Sleepiness Scale and the Fatigue Severity Scale, respectively. Mean Sleep Latency (SL) on the MSLT was significantly shorter in SAHS patients than in CFS patients and CFS patients showed significantly shorter mean SL than matched controls but within normal range. Subjective sleepiness was greatest in SAHS patients and subjective fatigue was highest in CFS patients. Affective symptoms showed highest intensities in CFS patients. While higher than the control group on all measures, compared to SAHS, the CFS group had higher subjective fatigue and lower subjective and objective sleepiness. Despite possible overlap in symptoms and signs of both daytime conditions, our data indirectly support the clinical distinction between fatigue and sleepiness.

Introduction : Les tableaux cliniques du syndrome de fatigue chronique (SFC) et du syndrome d'apnees hypopnees du sommeil (SAHS) sont en general associes a des plaintes de sommeil non-recuperateur et de symptomes affectifs. Le SFC est un diagnostic ou l'on suspecte frequemment la presence d'un trouble du sommeil primaire (TSP) non detecte. Objectif : Le but de l'etude etait de clarifier s'il existe des similitudes entre un groupe de patients SFC purs sans TSP ni comorbidites significatives et un groupe de patients SAHS en terme de proportions de stades de sommeil et d'intensite de symptomes affectifs. Methodes: Nous avons etudie les caracteristiques de 32 patients SFC (âge moyen 41.9 ± 8.7, 25 femmes) et de 30 patients SAHS (âge moyen 43.7 ± 6.7, 13 femmes) d'âge similaire, presentant un temps de sommeil total et des efficiences de sommeil similaires. Lintensite des symptomes affectifs etait mesuree a l'aide des echelles de depression et d'anxiete de Zung. Resultats : Les deux groupes de patients avaient des scores significativement superieurs au niveau des deux echelles que des sujets controles (p < 0.001). Lanxiete etait plus intense dans le groupe SFC que dans le groupe SAHS (p < 0.001). Par contre nous n'avons pas releve de difference au niveau des symptomes depressifs. La structure et les proportions du sommeil NREM dans le SFC sont differentes de ce que l'on observe dans un TSR Nos resultats confirment une distribution paradoxale du sommeil NREM ainsi qu'une elevation d'activite de type alpha a l'EEG pendant le sommeil lent profond chez les patients SFC.

Personality may play a role in the predisposition, the precipitation and/or the maintenance of the CFS. Thirty-six consecutively examined female patients hospitalised for a sleep workup, filled out a Temperament and Character Inventory (TCI) questionnaire. A MANOVA compared the patientswith a control group of femalesmatched for age. Significant scores were obtained for dimensions such as Harm Avoidance, Reward Dependence, and Self-Directedness. However, the only subdimension of Harm Avoidance that proved significantly higher in CFS than in controls was "Fatigability,"; which is likely to overlap with the core CFS symptom. All in all, the personality structure does not appear to play a major role in the CFS.

Background/Aims: One of the core symptoms of the chronic fatigue syndrome (CFS) is unrefreshing sleep and a subjective sensation of poor sleep quality. Whether this perception can be expressed, in a standardized questionnaire as the Pittsburgh Sleep Quality Index (PSQI), has to our knowledge never been documented in CFS. Furthermore, correlations of subjective fatigue, PSQI, affective symptoms and objective parameters such as sleep efficiency are poorly described in the literature. Methods: Using a cross-sectional paradigm, we studied subjective measures like PSQI, Fatigue Severity Scale scores and intensity of affective symptoms rated by the Hamilton Depression and Anxiety scales as well as objective sleep quality parameters measured by polysomnography of 28 ‘pure’ (no primary sleep and no psychiatric disorders) CFS patients compared to age- and gender-matched healthy controls. Results: The PSQI showed significantly poorer subjective sleep quality in CFS patients than in healthy controls. In contrast, objective sleep quality parameters, like the Sleep Efficiency Index (SEI) or the amount of slow-wave sleep did not differ significantly. Subjective sleep quality showed a correlation trend with severity of fatigue and was not correlated with the intensity of affective symptoms in CFS. Conclusion: Our findings indicate that a sleep quality misperception exists in CFS or that potential nocturnal neurophysiological disturbances involved in the nonrecovering sensation in CFS are not expressed by sleep variables such as the SEI or sleep stage distributions and proportions.

Une approche multidimensionnelle permet de mieux prendre en compte les difficultes auxquelles sont confrontes les patients atteints du syndrome de fatigue chronique. Elle permet aussi de cibler individuellement les symptomes et leur traitement. Une telle approche a ete realisee par analyse factorielle chez 298 patients par Vercoulen et al. (I994). Les variables concernant le sommeil. sont cependant cardinaux dans ce syndrome et provenaient uniquement de questionnaires dans l'etude citee. Il etait interessant de reproduire les grandes lignes de cette etude en integrant de telles variables objectives. Par ailleurs, ce type d'analyse devait permettre d'examiner de facon exploratoire a quelles variables specifiques du sommeil etaient liees les dimensions de fatigue examinees par une serie d'echelles psychometriques. Les resultats de l'analyse factorielle integrant ces variables objectives different notablement de l'etude precitee, en raison probablement de differences de criteres de selection et d'echelles utilisees. Les facteurs permettent d'associer diverses dimensions du syndrome de fatigue chronique a des anomalies specifiques du sommeil et mettent en question l'unicite de ce syndrome defini tres largement par son symptome.