L’appareillage en pression positive continue améliore le contrôle cognitif de la marche dans le syndrome d’apnées obstructives du sommeil sévère

Obstructive sleep apnoea syndrome (OSAS) has structural and functional cerebral consequences, which involve cognitive and gait limitations. Severe OSAS is associated with higher stride time variability (STV), a clinical biomarker of cognitive gait control. The impact of continuous positive airway pressure treatment (CPAP) on STV in severe OSAS has never been assessed. Prospective, controlled study evaluating the effect of 8 weeks of CPAP treatment in 12 severe OSAS patients (age=57.2±8.9 years, BMI=27.4±3.1 kg.m-2, AHI=46.3±11.7) compared to 10 matched control subjects. Spatiotemporal gait parameters are recorded at spontaneous speed and STV calculated. The cognitive control of gait and posture is assessed using a dual task paradigm (gait or posture and cognitive task (Stroop test) performed simultaneously). Performance at Stroop test is evaluated by calculating the correct response rate. Before CPAP, OSAS patients show a greater STV compared to controls (3.1±1.1% vs 2.1±0.5%, p=0.02), a higher centre of pressure area (131.2±79.8mm² vs 66.9±21.9mm², p=0.02) and a lower correct response rate in dual task condition while walking (p<0.001) or standing (p<0.001). After CPAP, STV (post-CPAP STV: 2.4±0.5%, p=0.005 vs pre-CPAP) and cognitive performance in dual task are improved in OSAS group and do not differ anymore from controls. Severe OSAS patients present an altered gait control, which may be improved by CPAP treatment. Our results suggest their cognitive origin.Le syndrome d’apnées obstructives du sommeil (SAOS) a des répercussions structurelles et fonctionnelles cérébrales responsables de limitations cognitives et locomotrices. Le SAOS sévère est associé à une plus grande variabilité du temps de cycle de marche (CVTCM), marqueur clinique du contrôle cognitif de la marche. L’effet du traitement par pression positive continue (PPC) sur le CVTCM dans le SAOS n’a jamais été étudié. Etude prospective contrôlée, évaluant l’effet de 8 semaines de traitement par PPC sur 12 patients avec SAOS sévère (âge=57.2±8.9 ans, IMC=27.4±3.1 kg.m-2, IAH=46.3±11.7) comparativement à 10 sujets contrôle appariés. Les paramètres spatiotemporels de marche sont enregistrés à vitesse spontanée et le CVTCM calculé. Le contrôle cognitif de la marche et de la posture est étudié par un paradigme de double tâche (marche ou posture et tâche cognitive (test de Stroop) simultanés). La performance au test de Stroop est évaluée par le taux de réponse correcte. Avant PPC, les patients SAOS présentent un CVTCM plus élevé comparativement aux contrôles (3.1±1.1% vs 2.1±0.5%, p=0.02), une surface d’oscillation du centre de pression plus élevée (131.2±79.8mm² vs 66.9±21.9mm², p=0.02) et un taux de réponse correcte en double tâche significativement plus bas à la marche (p<0.001) et en posture (p<0.001). Après PPC, le CVTCM (post-PPC CVTCM : 2.4±0.5%, p=0.005 vs pré-PPC) et les performances cognitives en double tâche sont améliorées dans le groupe SAOS et ne différent plus des contrôles. Les patients porteurs d’un SAOS sévère présentent une altération du contrôle locomoteur qui semble être amélioré par le traitement par PPC. Nos données suggèrent leur origine cognitive

Into thin air — Entraînement en altitude etconditionnement hypoxique : du sportif au malade

National audienc

Into thin air — Entraînement en altitude etconditionnement hypoxique : du sportif au malade

National audienc

Reshaping Sleep Apnea Care: Time for Value-based Strategies

International audienc

Neural substrates of reduced walking activity after supratentorial stroke: A voxel-based lesion symptom mapping study

International audienceBackground: 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 this cross-sectional study, 33 community-dwelling stroke survivors (age: 63.9 ± 12.9 years; % female: 36.4%; NIHSS at admission: 3.3 ± 4.0) were prospectively recruited at least 3 months after a first ever, unilateral, supratentorial stroke confirmed by brain magnetic resonance imaging. Walking activity was measured by daily step counts (steps∙day-1), recorded using an Actigraph GT3x+ triaxial accelerometer over 7 consecutive days. Voxel-based lesion-symptom mapping was performed to identify brain areas associated with walking activity following stroke.Results: Participants presented 4491.9 ± 2473.7 steps∙day-1. Lower levels of walking activity were related to lesions of the posterior part of the putamen, of the posterior limb of the internal capsule and of the anterior part of the corona radiata. No cortical region was associated with walking activity.Conclusions: Our preliminary results identify subcortical neuroanatomical correlates for reduced walking activity following stroke. If confirmed, these results could serve as a rationale for the development of targeted rehabilitative strategy to improve mobility after stroke

Current Knowledge and Perspectives for Pharmacological Treatment in OSA

International audienc

The individual and societal prices of non-adherence to continuous positive airway pressure, contributors, and strategies for improvement

International audienceIntroduction: Continuous positive airway pressure (CPAP) is the first-line therapy for obstructive sleep apnea (OSA). CPAP is highly effective for improving symptoms and quality of life, but the major issue is adherence, with up to 50% of OSA discontinuing CPAP in the first 3 years after CPAP initiation.Areas covered: We present the individual and societal costs of non-adherence to CPAP, factors associated with non-adherence to CPAP, as well as current strategies for improving adherence including telehealth, couple-based interventions, and behavioral interventions. We also report on challenges and pitfalls for the visualization and analysis of CPAP remote monitoring platforms.Expert opinion: CPAP termination rates and adherence to therapy remain major issues despite technical improvements in CPAP devices. The individual and societal price of non-adherence to CPAP for OSA patients goes beyond excessive sleepiness and includes cardiovascular events, all-cause mortality, and increased health costs. Strategies for improving CPAP adherence should be individually tailored and aim to also improve lifestyle habits including physical activity and diet. Access to these strategies should be supported by refining visualization dashboards of CPAP remote monitoring platforms, and by disseminating telehealth and innovative analytics, including artificial intelligence

Cognitive-motor dual-task interference modulates mediolateral dynamic stability during gait in post-stroke individuals

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 post-strokes and 10 healthy controls) while walking in single-task (normal gait) and four different dual-tasks (cognitive-motor interference). Positions of the extrapolated center of mass and mediolateral widths of both margin of stability and base of support were extracted from 35 marker trajectories. Post-stroke participants presented larger margin of stability and base of support than controls during single-task (both p < 0.01), with a larger margin of stability on the non-paretic side than on the paretic side at ipsilateral foot-strike (p < 0.05). No significant effect of the dual-task was found between groups. In post-stroke participants, dual-task induced slight modification of the mediolateral stability strategy, as the margin of stability was not different between the two limbs at foot-strike, and significantly reduced the performance in every cognitive task. Post-stroke participants increased their dynamic stability in the frontal plane in single-task by extending their base of support and mainly relying on their non-paretic limb. Under cognitive-motor interference (dual-task), post-stroke participants prioritized dynamic stability over cognitive performance to ensure a safe locomotion. Thus, rehabilitation programs should consider both dynamic balance and dual-task training, even at a chronic delay following stroke, to reduce the risk of fall in post-stroke individuals

Excessive Erythrocytosis and Chronic Mountain Sickness in Dwellers of the Highest City in the World

International audienc

Classification of Factors Effect on Sleep in Individuals with Down Syndrome

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 measure physical activity and sleep–wake patterns. The corresponding data were also obtained by survey and polysomnography. The apnea-hypopnea index (AHI) is calculated from the number of apneas and hypopneas per hour of sleep according to international guidelines. Results: Polysomnography showed SDB based on AHI in 95% of adults: 50% had severe SDB, 22.5% presented moderate and 22.5% mild SDB, predominantly in males. They had poor sleep quality (80.1%) and low PA levels. Using statistical classification methods, we observed three clusters with two opposite profiles. Clusters 2 and 3 showed low PA indices (daily steps: 5719 and 5310, respectively) and severe SDB (AHI = 33.6 and 55.5 events/h), high age and high gonial angle. Cluster 1 showed high PA (mean count of daily steps: 6908) and mild to moderate SDB (AHI = 16.8 events/h), low age and low gonial angle. Conclusions: Our findings suggest that there are different profiles (age, gender, obesity, gonial angle) that are associated with SDB in adults with DS. These results suggest that this may represent important factors to consider when planning health promotion and prevention