Groupe et supergroupe conformes de l'espace-temps et contractions

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

Efficacy of cognitive-behavioural therapy interventions on reducing burden for caregivers of older adults with a neurocognitive disorder : A systematic review and metaanalysis

Background: By 2025, 34 million people worldwide will be living with Alzheimer's disease or another form of dementia (i.e., neurocognitive disorders). Symptoms of cognitive disorders include memory deficits and executive deficits; these and other symptoms have functional repercussions on daily activities such as doing chores, taking medication and preparing meals. People with neurocognitive disorders often rely on a caregiver to alleviate the impact of their symptoms, but this help has consequences for the caregiver. Indeed, caregivers report subjective burden, depressive symptoms, stress, anxiety and a lower quality of life than noncaregivers. Multiple cognitive-behavioural therapy (CBT) trials have been conducted to reduce these symptoms for caregivers, and two meta-analyses have suggested that this method could be beneficial in reducing depressive symptoms. However, no meta-analysis has been conducted to evaluate the efficacy of this type of intervention on reducing subjective burden. Method: Eligibility criteria for the individual studies were determined using the PICOS strategy recommended by the PRISMA Statement. Articles were selected from PsycNet, MEDLINE, AgeLine and ProQuest Dissertation and Theses for the period from 2000 to 2017. Article selection, data extraction and bias analysis for individual studies was completed by two independent authors who used a consensus procedure when discrepancies occurred. The statistics Q, df, p value, I-square and Tau-squared were computed. Standardized effect sizes (Hedges’s g) were also computed for all studies. Result: A total of 20 articles were included in the systematic review. Statistics suggested there was no significant heterogeneity, and a fixed-effect model was used. Ten studies (N = 200 caregivers) evaluated the efficacy of CBT in reducing subjective burden, and the meta-analysis suggested a significant reduction in subjective burden following CBT. Additionally, 17 studies (N = 437 caregivers) evaluated the efficacy of CBT in reducing depressive symptoms, and the meta-analysis revealed a significant reduction for these caregivers following CBT. Conclusion: CBT for caregivers of individuals with a neurocognitive disorder was beneficial in reducing subjective burden and depressive symptoms but had no impact on stress, anxiety or quality of life

Childhood Socioeconomic Status Does Not Predict Late-Life Cognitive Decline in the 1936 Lothian Birth Cohort

This study examined childhood socioeconomic status (SES) as a predictor of later life cognitive decline. Data came from 519 participants in the Lothian Birth Cohort 1936 (LBC1936) study. SES measures at 11 years of age included parental educational attainment, father’s occupational status, household characteristics and a composite measure of global childhood SES (i.e., a total of low SES childhood indicators). Cognitive abilities were assessed by the Mini-Mental State Exam at ages 69.8, 72.8 and 76.7 years. Most indicators of low childhood SES (i.e., father manual worker, less than secondary school father education, household overcrowding, exterior located toilet, and global childhood SES) did not predict cognitive decline between the ages of 69.8 and 76.7. Participants with less educated mothers showed an increase in cognitive decline (β = −0.132, p = 0.048, and CI = −0.80, −0.00). The relationship between maternal educational attainment and cognitive decline became non-significant when controlling for adult SES (i.e., participant educational attainment and occupation). Adult SES did not mediate the latter relationship. This study provides new evidence that childhood SES alone is not strongly associated with cognitive decline. New knowledge is critical to improving population health by identifying life span stages in which interventions might be effective in preventing cognitive decline

What place for ethics? An overview of ethics teaching in occupational therapy and physiotherapy programs in Canada

Purpose: The recent introduction of master’s level curricula for Occupational Therapy and Physiotherapy training programs in Canada raises both challenges and opportunities to address ethical issues during professional training. This study evaluated the inclusion of ethics content in course descriptions and course calendars in order to develop a preliminary understanding of how rehabilitation ethics is taught in Canadian universities. Method: We reviewed the ethics content in the online curricula of 27 Canadian rehabilitation programs (OT & PT). Courses addressing ethical issues were identified through keyword searches, and were then subjected to both quantitative and textual descriptive analyses. Results: The mean proportion of credits allotted to courses that included ethics terminology was 5.9% (SD=1.4) for OT and 6.5% (SD=4.8) for PT (p=0.69). The most common terms in the course descriptions were ‘ethics/ethical’ followed by ‘legal’, ‘professionalism’, ‘deontology’ and ‘regulatory’. Textual analysis revealed eight course topics, the most frequent being: standards of practice, ethical decision-making, clinical courses and mediation/communication. Conclusion: With the growing recognition and status of occupational therapy and physiotherapy in the healthcare system, and corresponding shifts in how professionals are being trained, it is crucial to assess and reflect upon the place accorded to and manner of teaching ethics

Effects of a mindfulness-based intervention on circulating cytokine levels in individuals with amnestic mild cognitive impairment : a pilot study

Peripheral inflammation plays an important role in the pathophysiology of Alzheimer’s disease (AD) and dysregulations in circulating levels of different inflammatory mediators are detectable as early as the mild cognitive impairment (MCI) stage towards AD. Depressive symptoms, another risk factor of AD, are often found in individuals with MCI and associated with heightened levels of peripheral inflammatory mediators. Diminution in depressive symptoms and alterations of peripheral inflammation profiles have been observed following Mindfulness-based interventions (MBIs). In this pilot randomized-control trial, the impact of a mindfulness-based intervention (MBI) was compared to that of a psychoeducation-based intervention (PBI) on the peripheral inflammation profile and depressive symptomatology of participants with MCI. Plasma samples and scores on the Geriatric Depression scale (GDS) were obtained from 12 participants per group before and after the 8-week interventions. Flow cytometry allowed for inter-group comparisons of the pro-inflammatory cytokines Interleukin (IL)-6 and Tumor Necrosis Factor (TNF)-α levels. Post-MBI, two tendencies stand out regarding inflammation profiles: 1) a decrease of TNF-α for participants having higher initial levels of this cytokine, and 2) an increase of IL-6 levels for all participants. In the PBI group, the cytokine levels remained unchanged post-intervention. Regarding depressive symptomatology, no significant variations were noted for both groups. Moreover, variations on depressive symptoms and peripheral levels of cytokines were not correlated. MBI could exert a physiological effect on an important feature of AD, namely inflammation. Furthermore, action mechanisms behind physiological and psychological effects of MBIs could stem from independent sources. This remains to be demonstrated with more robust data

Links Between Metabolic and Structural Changes in the Brain of Cognitively Normal Older Adults: A 4-Year Longitudinal Follow-Up

We aimed to longitudinally assess the relationship between changing brain energy metabolism (glucose and acetoacetate) and cognition during healthy aging. Participants aged 71 ± 5 year underwent cognitive evaluation and quantitative positron emission tomography (PET) and magnetic resonance imaging (MRI) scans at baseline (N = 25) and two (N = 25) and four (N = 16) years later. During the follow-up, the rate constant for brain extraction of glucose (Kglc) declined by 6%–12% mainly in the temporo-parietal lobes and cingulate gyri (p ≤ 0.05), whereas brain acetoacetate extraction (Kacac) and utilization remained unchanged in all brain regions (p ≥ 0.06). Over the 4 years, cognitive results remained within the normal age range but an age-related decline was observed in processing speed. Kglc in the caudate was directly related to performance on several cognitive tests (r = +0.41 to +0.43, allp ≤ 0.04). Peripheral insulin resistance assessed by the homeostasis model assessment of insulin resistance (HOMA-IR) was significantly inversely related to Kglc in the thalamus (r = −0.44, p = 0.04) and in the caudate (r = −0.43, p = 0.05), and also inversely related to executive function, attention and processing speed (r = −0.45 to −0.53, all p ≤ 0.03). We confirm in a longitudinal setting that the age-related decline in Kglc is directly associated with declining performance on some tests of cognition but does not significantly affect Kacac

The Influence of birth cohorts on future cognitive decline

Background: Slowed rates of cognitive decline have been reported in individuals with higher cognitive reserve (CR), but interindividual discrepancies remain unexplained. Few studies have reported a birth cohort effect, favoring later-born individuals, but these studies remain scarce. Objective: We aimed to predict cognitive decline in older adults using birth cohorts and CR. Methods:Within the Alzheimer’s Disease Neuroimaging Initiative, 1,041 dementia-free participants were assessed on four cognitive domains (verbal episodic memory; language and semantic memory; attention; executive functions) at each follow-up visit up to 14 years. Four birth cohorts were formed according to the major historical events of the 20th century (1916–1928; 1929–1938; 1939–1945; 1946–1962). CR was operationalized by merging education, complexity of occupation, and verbal IQ. We used linear mixed-effect models to evaluate the effects of CR and birth cohorts on rate of performance change over time. Age at baseline, baseline structural brain health (total brain and total white matter hyperintensities volumes), and baseline vascular risk factors burden were used as covariates. Results: CR was only associated with slower decline in verbal episodic memory. However, more recent birth cohorts predicted slower annual cognitive decline in all domains, except for executive functions. This effect increased as the birth cohort became more recent. Conclusion: We found that both CR and birth cohorts influence future cognitive decline, which has strong public policy implications

Screening tools to identify patients with complex health needs at risk of high use of health care services : a scoping review

Background : Many people with chronic conditions have complex health needs often due to multiple chronic conditions, psychiatric comorbidities, psychosocial issues, or a combination of these factors. They are at high risk of frequent use of healthcare services. To offer these patients interventions adapted to their needs, it is crucial to be able to identify them early. Objective : The aim of this study was to find all existing screening tools that identify patients with complex health needs at risk of frequent use of healthcare services, and to highlight their principal characteristics. Our purpose was to find a short, valid screening tool to identify adult patients of all ages. Methods : A scoping review was performed on articles published between 1985 and July 2016, retrieved through a comprehensive search of the Scopus and CINAHL databases, following the methodological framework developed by Arksey and O’Malley (2005), and completed by Levac et al. (2010). Results : Of the 3,818 articles identified, 30 were included, presenting 14 different screening tools. Seven tools were self-reported. Five targeted adult patients, and nine geriatric patients. Two tools were designed for specific populations. Four can be completed in 15 minutes or less. Most screening tools target elderly persons. The INTERMED self-assessment (IM-SA) targets adults of all ages and can be completed in less than 15 minutes. Conclusion : Future research could evaluate its usefulness as a screening tool for identifying patients with complex needs at risk of becoming high users of healthcare services

Inosculation of tissue-engineered capillaries with the host's vasculature in a reconstructed skin transplanted on mice.

The major limitation for the application of an autologous in vitro tissue-engineered reconstructed skin (RS) for the treatment of burnt patients is the delayed vascularization of its relatively thick dermal avascular component, which may lead to graft necrosis. We have developed a human endothelialized reconstructed skin (ERS), combining keratinocytes, fibroblasts and endothelial cells (EC) in a collagen sponge. This skin substitute then spontaneously forms a network of capillary-like structures (CLS) in vitro. After transplantation to nude mice, we demonstrated that CLS containing mouse blood were observed underneath the epidermis in the ERS in less than 4 days, a delay comparable to our human skin control. In comparison, a 14-day period was necessary to achieve a similar result with the non-endothelialized RS. Furthermore, no mouse blood vessels were ever observed close to the epidermis before 14 days in the ERS and the RS. We thus concluded that the early vascularization observed in the ERS was most probably the result of inosculation of the CLS network with the host's capillaries, rather than neovascularization, which is a slower process. These results open exciting possibilities for the clinical application of many other tissue-engineered organs requiring a rapid vascularization