14 research outputs found
La loi sur l'assurance automobile, fait-elle échec à un recours en responsabilité médicale et/ou hospitaliÚre?
Résumé: Le législateur québécois a instauré avec la Loi sur l'assurance automobile un compromis social, suivant lequel une victime d'accident d'automobile a droit à une compensation automatique et limitée pour un préjudice causé par un accident. En contrepartie, les indemnités accordées à la victime d 'un accident d'automobile tiennent lieu de tous ses droits et recours en raison de son préjudice corporel et nulle action à ce sujet n'est reçue devant les tribunaux de droit commun. La jurisprudence de la Cour supérieure du Québec est contradictoire à savoir si un recours parallÚle devant un tribunal civil est permis contre un tiers allégué fautif dans un contexte d'indemnités versées par la SAAQ suite à un accident d'automobile. Nous analyserons donc dans le présent essai la portée de la Loi sur l'assurance automobile afin de démontrer qu'une faute médicale et/ou hospitaliÚre subséquente à un accident d'automobile constitue un fait nouveau, indépendant de l'usage de l'automobile et interrompant le lien de causalité avec l'automobile et faisant ainsi obstacle à l'application de la loi et ce, malgré que cette faute soit survenue avant la consolidation des dommages causés par l'accident d 'automobile et malgré les indemnités perçues par la victime pour l'ensemble de ses dommages.||Abstract: The Quebec legislator established with the Automobile Insurance Act a social compromise in which an automobile accident victim is entitled to automatic and limited compensation for an injury caused by an accident. In return, the compensation awarded to the victim of an automobile accident stands in lieu of all rights and remedies by reason of his bodily injury and no action in that respect shall be admitted before any court of justice. There is contradictory case law from the Superior Court of Quebec as to whether parallel proceedings before a civil court are allowed against an allegedly liable third party in a context of compensation paid by the SAAQ following an automobile accident. This essay analyses the scope of the Automobile Jnsurance Act to show that an act of medical malpractice and/ or a hospital's breach of duty subsequent to a car accident is a new fact, independent of the use of the car, thus breaking the causal link with the automobile and precluding the application of the law, despite that this fault occurred prior to the consolidation of the damages caused by the automobile accident and despite the compensation received by the victim for all its damage
CaractĂ©risation de la substance grise cĂ©rĂ©brale dans lâapnĂ©e obstructive du sommeil chez les personnes dâĂąge moyen et ĂągĂ©es
LâapnĂ©e obstructive du sommeil (AOS) est lâun des troubles du sommeil les plus frĂ©quents chez lâadulte et sa prĂ©valence augmente avec lâĂąge. Elle se caractĂ©rise par des arrĂȘts rĂ©pĂ©tĂ©s de la respiration au cours du sommeil, menant Ă la prĂ©sence de fragmentation du sommeil et Ă de lâhypoxĂ©mie intermittente. Lorsque non traitĂ©, ce trouble peut mener Ă diverses consĂ©quences non nĂ©gligeables sur la santĂ© des individus qui en sont atteints, incluant sur la santĂ© du cerveau. LâAOS est dâailleurs de plus en plus reconnue comme Ă©tant un possible facteur de risque de dĂ©clin cognitif et de dĂ©mence. Dans ce contexte, quelques Ă©tudes transversales ont caractĂ©risĂ© le volume de la substance grise cĂ©rĂ©brale chez des adultes vieillissants atteints dâAOS, avec des rĂ©sultats variables. En effet, certaines Ă©tudes ont notĂ© de plus grands volumes de substance grise chez les personnes avec une AOS plus sĂ©vĂšre, alors que dâautres ont retrouvĂ© des plus petits volumes chez cette mĂȘme population. Ce qui explique la variabilitĂ© entre les Ă©tudes demeure Ă ce jour mal compris, bien que certaines hypothĂšses aient Ă©mergĂ©.
Ainsi, cette thĂšse vise Ă Ă©valuer lâassociation entre la sĂ©vĂ©ritĂ© de lâAOS et le volume de substance grise cĂ©rĂ©brale chez des personnes dâĂąge moyen et ĂągĂ©es de maniĂšre transversale et longitudinale. La premiĂšre Ă©tude de cette thĂšse se base sur des techniques de neuroimagerie afin dâĂ©valuer les liens entre la sĂ©vĂ©ritĂ© de lâAOS et le volume de la substance grise cĂ©rĂ©brale des sous-rĂ©gions du lobe temporal mĂ©dian, soit lâhippocampe, le cortex entorhinal et le cortex parahippocampique. Celles-ci ont Ă©tĂ© ciblĂ©es puisquâelles peuvent ĂȘtre affectĂ©es tĂŽt dans la progression de la pathologie de la maladie dâAlzheimer (MA). De plus, nous avons testĂ© lâeffet dâune correction de la portion dâeau libre sur les volumes cĂ©rĂ©braux. Finalement, nous avions comme objectif de mieux comprendre si certaines caractĂ©ristiques dĂ©mographiques ou cliniques de nos participants pouvaient avoir un impact sur les associations observĂ©es. Nous avons observĂ© quâune AOS plus sĂ©vĂšre Ă©tait associĂ©e Ă des volumes de substance grise plus grands de certaines sous-rĂ©gions du lobe temporal mĂ©dian (hippocampe et cortex entorhinal), mais seulement chez des groupes de participants spĂ©cifiques, soit les femmes, les participants plus ĂągĂ©s et ceux prĂ©sentant un trouble cognitif lĂ©ger de type amnĂ©sique. Le fait dâapporter une correction pour la portion dâeau libre aux volumes mesurĂ©s a rendu non significatives les associations observĂ©es. Il est donc possible que la prĂ©sence accrue dâeau extracellulaire, suggĂ©rant de lâĆdĂšme cĂ©rĂ©bral, puisse expliquer la prĂ©sence de plus grands volumes chez les participants prĂ©sentant une AOS plus sĂ©vĂšre.
La deuxiĂšme Ă©tude visait quant Ă elle Ă Ă©valuer les changements structurels des sous-rĂ©gions du lobe temporal mĂ©dian associĂ©s Ă la sĂ©vĂ©ritĂ© de lâAOS chez des personnes dâĂąge moyen et ĂągĂ©es sur une pĂ©riode dâenviron 2 ans. Nous avons dĂ©montrĂ© que chez nos participants nâayant pas utilisĂ© un traitement pour lâAOS, la prĂ©sence dâinteraction entre la sĂ©vĂ©ritĂ© de lâAOS et lâĂąge permettait dâexpliquer les changements annuels de volume de substance grise. De fait, les participants plus jeunes de notre Ă©chantillon ( 75 ans) avec une plus grande sĂ©vĂ©ritĂ© dâAOS prĂ©sentaient quant Ă eux une plus grande atrophie au fil du temps dans certaines rĂ©gions, soit lâhippocampe et le cortex entorhinal. Ces rĂ©sultats supportent donc une hypothĂšse biphasique des changements au niveau de la substance grise cĂ©rĂ©brale chez les gens prĂ©sentant de lâAOS, avec une premiĂšre phase caractĂ©risĂ©e par des augmentations de volume chez les adultes plus jeunes, menant Ă©ventuellement Ă de lâatrophie chez les personnes plus ĂągĂ©es.
Cette thĂšse permet dâavoir un portrait plus clair sur la nature des changements et des mĂ©canismes impliquĂ©s dans lâassociation entre la sĂ©vĂ©ritĂ© de lâAOS et les volumes de substance grise. Lâun des apports importants est lâutilisation dâune nouvelle mĂ©thodologie afin dâobtenir une portion dâeau libre, ce qui a permis de mieux comprendre lâapport potentiel de mĂ©canismes pouvant sous-tendre les changements structuraux observĂ©s, notamment lâĆdĂšme cĂ©rĂ©bral. De plus, lâĂ©valuation des caractĂ©ristiques individuelles des participants a permis dâexpliquer partiellement les incongruences entre les Ă©tudes prĂ©cĂ©dentes. Dans le cadre des Ă©tudes incluses dans cette thĂšse, nous avons observĂ© des changements plus marquĂ©s chez les femmes. Nous avons Ă©galement pu dĂ©montrer que lâĂąge des individus atteints dâAOS pouvait influencer significativement le patron de changements observĂ©s. Les rĂ©sultats de cette thĂšse pourraient donc permettre de mieux cibler les personnes avec AOS qui pourraient le plus bĂ©nĂ©ficier dâun traitement pour maintenir leur santĂ© cĂ©rĂ©brale.Obstructive sleep apnea (OSA) is one of the most common sleep disorders in adults, and its prevalence increases with age. It is characterized by repeated pauses in breathing during sleep, leading to sleep fragmentation and intermittent hypoxemia. If left untreated, this disorder can have numerous consequences, including on the brainâs health. OSA is increasingly recognized as a risk factor for cognitive decline and dementia. In this context, cross-sectional studies have characterized brain gray matter volume in aging adults with OSA, with variable results. Indeed, some studies have noted greater gray matter volumes in people with more severe OSA, while others have found smaller volumes in this same population. What explains the variability between studies remains poorly understood, although some hypotheses have emerged.
Thus, this thesis aims to assess the association between OSA severity and cerebral gray matter volume in middle-aged and elderly individuals using cross-sectional and longitudinal designs. The first study in this thesis uses neuroimaging techniques to assess the links between OSA severity and cerebral gray matter volume of the medial temporal lobe subregions, i.e. the hippocampus, entorhinal cortex and parahippocampal cortex. These were chosen as they can be affected early in the progression of Alzheimer's disease (AD) pathology. We also corrected our brain volumes for free-water portion. Finally, we aimed to better understand whether certain demographic or clinical characteristics of our participants might have an impact on the associations observed. We noted that more severe OSA was associated with larger gray matter volumes in certain subregions of the medial temporal lobe (hippocampus and enthorinal cortex), but only in specific groups of participants: women, older participants and those with amnestic mild cognitive impairment. Correcting our volumes for free-water portion rendered the associations nonsignificant. It is therefore possible that the presence of extracellular water, suggestive of cerebral edema, could explain the presence of larger volumes in participants with more severe OSA.
The second study aimed to assess longitudinal structural changes associated with OSA severity in middle-aged and elderly people over a period of around 2 years. We found that in participants who did not use treatment for OSA, the presence of interactions between OSA severity and age were associated with the annual changes in gray matter volume. Indeed, younger participants (75 years old) with greater OSA severity showed greater hippocampal and entorhinal cortex atrophy over time. These results therefore support a biphasic hypothesis of changes in cerebral gray matter in people with OSA, with an initial phase characterized by volume increases in younger adults, eventually leading to atrophy in older people.
This thesis provides a clearer picture of the nature of the changes and mechanisms involved in the association between OSA severity and gray matter volumes. An important contribution is the use of a new methodology to obtain a free-water portion, which allows to better understand the potential contribution of mechanisms that may underlie the structural changes observed, notably cerebral edema. In addition, the assessment of participants' individual characteristics helped to partially explain incongruities between previous studies. Indeed, in the studies included in this thesis, we observed more marked changes in certain subgroups of participants, notably women. We were also able to demonstrate that the age of individuals with OSA could significantly influence the pattern of changes observed, either gray matter hypertrophy or atrophy. The results of this thesis could therefore make it possible to target specific subgroups of individuals suffering from OSA who may be at greater risk of displaying changes in gray matter structure, and thus promote screening and treatment when necessary
Reduced rapid eye movement sleep in late middle-aged and older apolipoprotein E É4 allele carriers
Study Objectives
Apolipoprotein E É4 (APOE4) is the strongest genetic risk factor for Alzheimerâs disease (AD). In addition, APOE4 carriers may exhibit sleep disturbances, but conflicting results have been reported, such that there is no clear consensus regarding which aspects of sleep are impacted. Our objective was to compare objective sleep architecture between APOE4 carriers and non-carriers, and to investigate the modulating impact of age, sex, cognitive status, and obstructive sleep apnea (OSA).
Methods
A total of 198 dementia-free participants aged >55 years old (mean age: 68.7 ± 8.08 years old, 40.91% women, 41 APOE4 carriers) were recruited in this cross-sectional study. They underwent polysomnography, APOE4 genotyping, and a neuropsychological evaluation. ANCOVAs assessed the effect of APOE4 status on sleep architecture, controlling for age, sex, cognitive status, and the apneaâhypopnea index. Interaction terms were added between APOE4 status and covariates.
Results
Rapid eye movement (REM) sleep percentage (Fâ
=â
9.95, pâ
=â
.002, ηp2â
=â
0.049) and duration (Fâ
=â
9.23, pâ
=â
.003, ηp2â
=â
0.047) were lower in APOE4 carriers. The results were replicated in a subsample of 112 participants without moderate-to-severe OSA. There were no significant interactions between APOE4 status and age, sex, cognitive status, and OSA in the whole sample.
Conclusions
Our results show that APOE4 carriers exhibit lower REM sleep duration, including in cognitively unimpaired individuals, possibly resulting from early neurodegenerative processes in regions involved in REM sleep generation and maintenance
Living ethics: a stance and its implications in health ethics
Moral or ethical questions are vital because they affect our daily lives: what is the best choice we can make, the best action to take in a given situation, and ultimately, the best way to live our lives? Health ethics has contributed to moving ethics toward a more experience-based and user-oriented theoretical and methodological stance but remains in our practice an incomplete lever for human development and flourishing. This context led us to envision and develop the stance of a âliving ethicsâ, described in this inaugural collective and programmatic paper as an effort to consolidate creative collaboration between a wide array of stakeholders. We engaged in a participatory discussion and collective writing process known as instrumentalist concept analysis. This process included initial local consultations, an exploratory literature review, the constitution of a working group of 21 co-authors, and 8 workshops supporting a collaborative thinking and writing process. First, a living ethics designates a stance attentive to human experience and the role played by morality in human existence. Second, a living ethics represents an ongoing effort to interrogate and scrutinize our moral experiences to facilitate adaptation of people and contexts. It promotes the active and inclusive engagement of both individuals and communities in envisioning and enacting scenarios which correspond to their flourishing as authentic ethical agents. Living ethics encourages meaningful participation of stakeholders because moral questions touch deeply upon who we are and who we want to be. We explain various aspects of a living ethics stance, including its theoretical, methodological, and practical implications as well as some barriers to its enactment based on the reflections resulting from the collaborative thinking and writing process
Altered resting-state functional connectivity patterns in late middle-aged and older adults with obstructive sleep apnea
IntroductionObstructive sleep apnea (OSA) is increasingly recognized as a risk factor for cognitive decline, and has been associated with structural brain alterations in regions relevant to memory processes and Alzheimerâs disease. However, it is unclear whether OSA is associated with disrupted functional connectivity (FC) patterns between these regions in late middle-aged and older populations. Thus, we characterized the associations between OSA severity and resting-state FC between the default mode network (DMN) and medial temporal lobe (MTL) regions. Second, we explored whether significant FC changes differed depending on cognitive status and were associated with cognitive performance.MethodsNinety-four participants [24 women, 65.7â±â6.9 years old, 41% with Mild Cognitive Impairment (MCI)] underwent a polysomnography, a comprehensive neuropsychological assessment and a resting-state functional magnetic resonance imaging (MRI). General linear models were conducted between OSA severity markers (i.e., the apnea-hypopnea, oxygen desaturation and microarousal indices) and FC values between DMN and MTL regions using CONN toolbox. Partial correlations were then performed between OSA-related FC patterns and (i) OSA severity markers in subgroups stratified by cognitive status (i.e., cognitively unimpaired versus MCI) and (ii) cognitive scores in the whole sample. All analyzes were controlled for age, sex and education, and considered significant at a pâ<â0.05 threshold corrected for false discovery rate.ResultsIn the whole sample, a higher apnea-hypopnea index was significantly associated with lower FC between (i) the medial prefrontal cortex and bilateral hippocampi, and (ii) the left hippocampus and both the posterior cingulate cortex and precuneus. FC patterns were not associated with the oxygen desaturation index, or micro-arousal index. When stratifying the sample according to cognitive status, all associations remained significant in cognitively unimpaired individuals but not in the MCI group. No significant associations were observed between cognition and OSA severity or OSA-related FC patterns.DiscussionOSA severity was associated with patterns of lower FC in regions relevant to memory processes and Alzheimerâs disease. Since no associations were found with cognitive performance, these FC changes could precede detectable cognitive deficits. Whether these FC patterns predict future cognitive decline over the long-term needs to be investigated
Luc Courchesne : observateur du monde
Catalogue prĂ©parĂ© sous la direction de Christine Bernier.Catalogue de lâexposition tenue au Carrefour des arts et des sciences, UniversitĂ© de MontrĂ©al,
du 13 avril au 19 juin 2022
La loi sur l'assurance automobile, fait-elle échec à un recours en responsabilité médicale et/ou hospitaliÚre?
Résumé: Le législateur québécois a instauré avec la Loi sur l'assurance automobile un compromis social, suivant lequel une victime d'accident d'automobile a droit à une compensation automatique et limitée pour un préjudice causé par un accident. En contrepartie, les indemnités accordées à la victime d 'un accident d'automobile tiennent lieu de tous ses droits et recours en raison de son préjudice corporel et nulle action à ce sujet n'est reçue devant les tribunaux de droit commun. La jurisprudence de la Cour supérieure du Québec est contradictoire à savoir si un recours parallÚle devant un tribunal civil est permis contre un tiers allégué fautif dans un contexte d'indemnités versées par la SAAQ suite à un accident d'automobile. Nous analyserons donc dans le présent essai la portée de la Loi sur l'assurance automobile afin de démontrer qu'une faute médicale et/ou hospitaliÚre subséquente à un accident d'automobile constitue un fait nouveau, indépendant de l'usage de l'automobile et interrompant le lien de causalité avec l'automobile et faisant ainsi obstacle à l'application de la loi et ce, malgré que cette faute soit survenue avant la consolidation des dommages causés par l'accident d 'automobile et malgré les indemnités perçues par la victime pour l'ensemble de ses dommages.||Abstract: The Quebec legislator established with the Automobile Insurance Act a social compromise in which an automobile accident victim is entitled to automatic and limited compensation for an injury caused by an accident. In return, the compensation awarded to the victim of an automobile accident stands in lieu of all rights and remedies by reason of his bodily injury and no action in that respect shall be admitted before any court of justice. There is contradictory case law from the Superior Court of Quebec as to whether parallel proceedings before a civil court are allowed against an allegedly liable third party in a context of compensation paid by the SAAQ following an automobile accident. This essay analyses the scope of the Automobile Jnsurance Act to show that an act of medical malpractice and/ or a hospital's breach of duty subsequent to a car accident is a new fact, independent of the use of the car, thus breaking the causal link with the automobile and precluding the application of the law, despite that this fault occurred prior to the consolidation of the damages caused by the automobile accident and despite the compensation received by the victim for all its damage