Baillieul Sébastien

Université Grenoble Alpes · Department of Medicine

Background—Adults with Down’s syndrome (DS) present lower physical fitness associated with heightened sedentary behaviors and motor skills impairments. Their etiologies and determinants seem to be heterogeneous. This study aims to evaluate physical fitness in adults with DS and to identify specific physical fitness profiles depending on gender and...

Sleep disorders are defined on the basis of diagnostic criteria presented in medical classifications. However, no consensus has emerged on the exact list of operational symptoms that should be systematically investigated in the field of sleep medicine. We propose a systematic analysis of sleep symptoms that figure in a set of self-reported multiple...

Background: Continuous positive airway pressure (CPAP) is the first-line therapy for obstructive sleep apnea (OSA). A high or variable residual apnea-hypopnea index (rAHI) reflects treatment failure and is potentially triggered by exacerbation of cardiovascular comorbidities. Previous studies showed that high rAHI and large rAHI variability are as...

Introduction Chronic mountain sickness (CMS) is a condition characterized by excessive erythrocytosis in response to chronic hypobaric hypoxia. CMS frequently triggers cardiorespiratory diseases such as pulmonary hypertension and right or left heart failure. Ambient hypoxia might be further amplified night-time by intermittent hypoxia related to sl...

While continuous positive airway pressure (CPAP) therapy has a strong evidence base for the treatment of obstructive sleep apnoea (OSA), its impact on cardiovascular comorbidity remains unclear. This journal club reviews three recent randomised controlled trials aimed to evaluate the impact of CPAP therapy in secondary prevention of cerebrovascular...

Left/right prefrontal cortex (PFC) activation is linked to positive/negative affects, respectively. Besides, larger left PFC oxygenation during exercise relates to higher cardiorespiratory fitness (CRF). High-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) in improving CRF. The influence of training o...

Objective: In obstructive sleep apnea patients on continuous positive airway pressure (CPAP) treatment there is growing evidence for a significant impact of the type of mask on the residual apnea-hypopnea index (rAHI). Here, we propose a method for automatically classifying the impact of mask changes on rAHI. Methods: From a CPAP telemonitoring...

Aim Intermittent hypoxia (IH) is considered to be a major contributor to obstructive sleep apnoea-related cardiovascular consequences. The present meta-analysis aimed to assess the effects of IH on cardiac remodelling, function and infarct size after myocardial ischaemia across different rodent species and IH severities. Methods and results Relevan...

Purpose Both prolonged exercise and acute high-altitude exposure are known to induce cardiac changes. We sought to describe the cardiac responses to speed climbing at high-altitude, including left ventricular (LV) performance assessment using the myocardial work index (MWI), a new index derived from 2D speckle tracking echocardiography (STE). Meth...

Background Obstructive sleep apnea (OSA) remains massively underdiagnosed, due to limited access to polysomnography (PSG), the highly complex gold standard for diagnosis. Performance scores in predicting OSA are evaluated for machine learning (ML) analysis applied to 3D maxillofacial shapes. Methods The 3D maxillofacial shapes were scanned on 280...

Purpose The combined effects of acute hypoxia and exercise on cognition remain to be clarified. We investigated the effect of speed climbing to high altitude on reactivity and inhibitory control in elite climbers. Methods Eleven elite climbers performed a speed ascent of the Mont-Blanc (4810 m) and were evaluated pre- (at 1000 m) and immediately p...

Background Considering the potential greater cardiocirculatory effects of high intensity interval training (HIIT), we hypothesized that a 2-month supervised a high volume short interval HIIT would induce greater improvements in CRF and cardiometabolic risk and increase long-term maintenance compared to isocaloric moderate intensity continuous train...

Résumé La fréquence des séjours en altitude (pour le travail, les loisirs, les voyages en avion ou en véhicule à moteur) justifie que soit posée la question de leur tolérance, en particulier chez des sujets porteurs de maladie respiratoire préexistante. La baisse de la pression barométrique, les variations de densité de l’air et les variations de t...

Sleep apnoea, one of the most common chronic diseases, is a risk factor for ischaemic stroke, stroke recurrence, and poor functional recovery after stroke. More than half of stroke survivors present with sleep apnoea during the acute phase after stroke, with obstructive sleep apnoea being the most common subtype. Following a stroke, sleep apnoea fr...

Rationale Sleep-disordered breathing (SDB) is highly prevalent after stroke. The clinical and ventilatory chemosensitivity characteristics of SDB, namely obstructive, central and coexisting obstructive and central sleep apnoea (coexisting sleep apnoea) following stroke are poorly described. Objective To determine the respective clinical and ventil...

Background: Sleep disordered breathing (SDB) is a frequent disorder with serious adverse health consequences in people with Down syndrome (DS). This study aims to evaluate and classify sleep and physical activity (PA) characteristics in adults with DS. Methods: Forty participants with DS wore an accelerometer for seven consecutive days to measur...

Background Continuous positive airway pressure (CPAP), the reference treatment for obstructive sleep apnoea (OSA), is used by millions of individuals worldwide with remote telemonitoring providing daily information on CPAP usage and efficacy, a currently underused resource. Here, we aimed to implement data science methods to provide tools for perso...

Neurologic disorders often affect sleep-wake and circadian patterns, either as a primary consequence of brain lesions that disrupt neuronal networks regulating sleep or circadian time or as a secondary consequence of underlying sensory or motor neuropathology. These SWCD may present in diverse ways, ranging from changes to sleep structure or EEG mi...

Background. Physical activity is a cornerstone for the management of obesity. Owing to, in part, lower pleasure, this population however perform very little exercise.[1] From a physiopsychological standpoint, left and right prefrontal cortex (PFC) activation are thought to be related to positive and negative affects, respectively.[2] Moreover, larg...

To determine the effect of continuous positive airway pressure (CPAP), the gold standard treatment for obstructive sleep apnea syndrome (OSAS), on gait control in severe OSAS patients. We conducted a randomized, double-blind, parallel-group, sham-controlled monocentric study in Grenoble Alpes University Hospital, France. Gait parameters were record...

Résumé Les patients porteurs d’un rhumatisme inflammatoire chronique tel que la polyarthrite rhumatoïde ou la spondyloarthrite présentent une combinaison de niveaux d’activité physique limités et des comportements sédentaires qui affectent à la fois les critères d’évaluation de la maladie et les comorbidités. L’innocuité de l’activité physique chez...

Résumé Introduction L’exposition hypoxique est à considérer comme un continuum, dont les effets dépendent de la dose et de la sensibilité individuelle à l’hypoxie. Le conditionnement hypoxique (CH) représente une stratégie innovante et prometteuse, allant de l’amélioration des performances humaines à des applications thérapeutiques. État des conn...

Abstract Background Sleep-disordered breathing (SDB) is highly prevalent in acute ischaemic stroke and is associated with worse functional outcome and increased risk of recurrence. Recent meta-analyses suggest the possibility of beneficial effects of nocturnal ventilatory treatments (continuous positive airway pressure (CPAP) or adaptive servo-vent...

Introduction Sleep disordered breathing (SDB) and ischemic stroke (IS) are intertwined pathologies. The topography of IS may interacts with SDB (vigilance, ventilatory and upper airway control). Objective To evaluate the association between stroke location and SDB after a first IS. Method Prospective monocentric cohort of patients aged 18–85 year...

Introduction Living in high altitude is challenging for the cardiovascular system, and some of highlanders develop a chronic mountain sickness (CMS). Only few data are available above the altitude of 4380 m. La Rinconada is the highest mining city in the world at an altitude of 5100 m. Objective To describe heart remodeling and pulmonary hemodynam...

Introduction Pathologies du sommeil et infarctus cérébral (IC) sont étroitement liés et possiblement la topographie de l’IC et la pathologie du sommeil interagissent (vigilance, commande ventilatoire et des voies aériennes supérieures). Objectifs L’objectif principal est d’évaluer la corrélation potentielle entre topographie lésionnelle d’un premi...

Background While millions of people are living permanently at high altitude (>2,500 m) worldwide, the mechanisms underlying their tolerance to chronic hypoxia and those responsible for the occurrence of chronic mountain sickness (CMS) remain to be elucidated. Excessive erythrocytosis (EE) is thought to be the main mechanism responsible for CMS symp...

The human brain is a perfect example of our dependence on oxygen. Brain physiological constraints render it vulnerable to hypoxia, such as encountered in environmental conditions (high altitude exposure) or pathological hypoxemic conditions. Among those pathological conditions, and due to its high prevalence in general population and the various le...

The 2019 European Respiratory Society (ERS) International Congress took place in Madrid, Spain, and served as a platform to find out the latest advances in respiratory diseases research. The research aims are to understand the physiology and consequences of those diseases, as well as the improvement in their diagnoses, treatments and patient care....

Objectif Pathologies du sommeil et infarctus cérébral (IC) sont étroitement liés et possiblement la topographie de l’IC et la pathologie du sommeil interagissent (vigilance, commande ventilatoire et des voies aériennes supérieures). Objectif corrélation entre topographie lésionnelle d’un premier IC et syndrome d’apnées du sommeil (SAS). Méthodes C...

New findings: What is the central question of this study? Impairment and subsequent improvement in cerebral oxygenation during acute and prolonged exposure to high altitude affects exercise performance. However, this study innovates by investigating the effect of acute and prolonged high-altitude exposure on cerebral hemodynamics during a submaxim...

Objective: To identify candidate biomarkers of walking recovery with motor tract integrity measurements using fractional anisotropy (FA) from the corticospinal tract (CST) and alternative motor pathways in patients with moderate to severe subacute stroke. Methods: Walking recovery was first assessed with generalized linear mixed model (GLMM) wit...

Connected health is a growing field and can be viewed from different perspectives, particularly in sleep apnea syndrome. The purpose of this review is to show how all these aspects of connected health are already used in the management of sleep apnea syndrome (SAS) and its comorbidities. First, it can give patients a better understanding and a bett...

Objectives: Fibromyalgia (FM) is a chronic painful condition partly due to alterations in pain modulation by the central nervous system. Multicomponent therapy (MT) and repetitive transcranial magnetic stimulation (rTMS) had both been reported as pain modulators in FM patients. The aim of this study was to compare the effects of rTMS on pain with...

Background: Most stroke patients exhibit low levels of walking activity, a key component of secondary stroke prevention. The predictors of walking activity may be multifactorial and are thus far partially understood. We aimed to study the neuroanatomic correlates of low levels of daily walking activity following hemispheric stroke. Methods: In t...

Introduction : La santé connectée est en plein essor et peut être envisagée à partir de différentes perspectives notamment dans le syndrome d’apnées du sommeil (SAS). Matériels et méthodes : L’objet de cette revue est de montrer comment toutes ces dimensions de la santé connectée s’appliquent déjà à la prise en charge du SAS et de ses comorbidités....

The 2018 European Respiratory Society (ERS) International Congress held in Paris, France, served as a platform to discover the latest research on respiratory diseases, the improvement in their treatments and patient care. Specifically, the scientific sessions organised by ERS Assembly 4 provided novel insights into sleep disordered breathing and fr...

Introduction: Central sleep apnea (CSA) syndrome has gained a considerable interest in the sleep field within the last 10 years. It is overrepresented in particular subpopulations such as patients with stroke or heart failure. Early detection and diagnosis, as well as appropriate treatment of central breathing disturbances during sleep remain chall...

Physical performance relies on the concerted action of myriad responses, many of which are under circadian clock control. Little is known, however, regarding the time-dependent effect on exercise performance at the molecular level. We found that both mice and humans exhibit daytime variance in exercise capacity between the early and late part of th...

Study objectives Sleep is altered at high altitude leading many mountaineers to use hypnotics in order to improve sleep efficiency. While after a full night at altitude the short-acting hypnotic zolpidem does not appear to alter cognitive function, residual adverse effects should be considered following early waking-up as performed by mountaineers....

Objective and background: Impaired cerebral blood flow and cerebrovascular reactivity to hypercapnia during wakefulness at rest as well as reduced exercise tolerance have been reported in severe obstructive sleep apnea (OSA) patients. Impaired cerebral oxygenation and hemodynamics can contribute to reduced exercise performance. We hypothesized tha...

Purpose: Lower muscle strength and endurance have been reported in severe obstructive sleep apnea (OSA). Increased intracortical inhibition previously reported at rest in OSA suggests central neuromuscular impairments in these patients. We hypothesized that (i) OSA patients demonstrate reduced knee extensor strength and endurance due to central im...

Objectif La force et l’endurance musculaire semblent être réduites chez le patient atteint de syndrome d’apnée obstructive du sommeil (SAOS) sévère. Cette étude visait à évaluer les mécanismes neuromusculaires de la fatigue induite par l’exercice chez le patient SAOS avant et après 8 semaines de traitement par pression positive continue (PPC). Mét...

Study aim Severe obstructive sleep apnoea (OSA) can lead to neurocognitive alterations, including gait impairments. The beneficial effects of continuous positive airway pressure (CPAP) on improving excessive daytime sleepiness and daily functioning have been documented. However, a demonstration of CPAP treatment efficacy on gait control is still la...

Study protocol. Full length french version. (PDF)

Pre-assessment visual testing, to ensure that subjects were able to properly distinguish colours by using the same screen setting as during the dual-task assessments. The four colours used in our Stroop test were consecutively displayed on the screen (A), then words written in the congruent font colour were displayed (B). Participants were instruct...

Ethical authorization. (PDF)

Study protocol. English language summary. (DOCX)

Many studies have investigated respiratory muscle strength (RMS) in cystic fibrosis (CF) and its relationship with exercise tolerance and quality of life. Only few studies investigated respiratory muscle endurance (RME) for which no standard assessment exists. Whether RME is altered in CF and its relationship with lung function, maximal exercise ca...

Gait asymmetry and dynamic balance impairments observed in post-stroke individuals increase their risk of fall. Moreover, walking while performing a cognitive task (i.e. dual-task) disturbs the control of balance in post-stroke individuals. Here we investigated the mediolateral dynamic stability in twenty-two community-dwelling participants (12 pos...

Introduction Après un accident vasculaire cérébral (AVC), la marche est altérée entraînant une modification de la coordination intramembre (CIM) [1]. La réalisation d’une tâche secondaire cognitive en marchant influence de manière négative les paramètres spatiotemporels de marche et augmente le risque de chute [2]. L’objectif de cette étude était d...

Robach et al. (2016) recently showed that 35.8% of alpinists attempting to ascend Mont Blanc consume at least one drug. The hypnotic Zolpidem is used by 8.4% of climbers to reduce sleep disturbances the night before the ascent. The present study aimed to assess residual effects of 10mg Zolpidem (dose recommended by the manufacturer) on cognitive pr...