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The Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) cohort study of the Canadian Consortium on Neurodegeneration in Aging (CCNA) is a national initiative to catalyze research on dementia, set up to support the research agendas of CCNA teams. This cross-country longitudinal cohort of 2310 deeply phenotyped subjects with various forms of dementia and mild memory loss or concerns, along with cognitively intact elderly subjects, will test hypotheses generated by these teams.
The COMPASS-ND protocol, initial grant proposal for funding, fifth semi-annual CCNA Progress Report submitted to the Canadian Institutes of Health Research December 2017, and other documents supplemented by modifications made and lessons learned after implementation were used by the authors to create the description of the study provided here.
The CCNA COMPASS-ND cohort includes participants from across Canada with various cognitive conditions associated with or at risk of neurodegenerative diseases. They will undergo a wide range of experimental, clinical, imaging, and genetic investigation to specifically address the causes, diagnosis, treatment, and prevention of these conditions in the aging population. Data derived from clinical and cognitive assessments, biospecimens, brain imaging, genetics, and brain donations will be used to test hypotheses generated by CCNA research teams and other Canadian researchers. The study is the most comprehensive and ambitious Canadian study of dementia. Initial data posting occurred in 2018, with the full cohort to be accrued by 2020.
Availability of data from the COMPASS-ND study will provide a major stimulus for dementia research in Canada in the coming years.
How cognitive impairment and frailty combine to impact on older adults’ Quality of Life (QoL) is little studied, but their inter-relationships are important given how often they co-occur. We sought to examine how frailty and cognitive impairment, as well as changes in frailty and cognition, are associated with QoL and how these relationships differ based on employment status and social circumstances.
Using the Survey of Health, Ageing, and Retirement in Europe data, we employed moderated regression, followed by simple slopes analysis, to examine how the relationships between levels of health (i.e., of frailty and cognition) and QoL varied as a function of sex, age, education, social vulnerability, and employment status. We used the same analysis to test whether the relationships between changes in health (over two years) and QoL varied based on these same moderators.
Worse frailty (b = −1.61, p < .001) and cognitive impairment (b = −0.08, p < .05) were each associated with lower QoL. Increase in frailty (b = −2.17, p < .001) and cognitive impairment (b = −0.25, p < .001) were associated with lower QoL. The strength of these relationships varied depending on interactions with age, sex, education, social vulnerability, and employment status. Higher social vulnerability was consistently associated with lower QoL in analyses examining both static health (b = −3.16, p < .001) and change in health (b = −0.66, p < .001).
Many predictors of QoL are modifiable, providing potential targets to improve older adults’ QoL. Even so, the relationships between health, cognition, and social circumstances that shape QoL in older adults are complex, highlighting the importance for individualized interventions.
A cricothyroidotomy is a life-saving procedure, performed as a final option to emergency airway algorithms, and is essential for all clinicians who perform emergency airway management. The bougie-assisted cricothyroidotomy (BAC) is a novel technique that may be performed faster and with fewer complications than other traditional approaches. There is no established standard set of steps to guide the instruction of BAC performance. This study sought to systematically develop a BAC checklist for novice instruction using a modified Delphi methodology and international airway experts.
A literature review informed the creation of a preliminary BAC checklist. A three round, modified Delphi method was used to establish a BAC checklist intended for novice-level instruction. The consensus level for each step and the final checklist were predefined at 80%. Participants were international airway experts identified by study personnel and snowball sampling.
Fourteen international airway experts across six acute care specialities participated in the study. The checklist was refined using a seven-point rating scale for each item and participant comments. A 17-item checklist was developed with expert consensus achieved after three rounds. Internal consistency, measured with Cronbach’s α, was 0.855 (95% confidence interval 0.73-0.94).
This modified Delphi-derived checklist is the first systematically developed list of essential steps for guiding BAC instruction for novice learners. This tool serves to standardize BAC skill instruction and provide learners with a structured and consistent set of steps for deliberate practice.
We present techniques for obtaining large (∼100 L STP) samples of ancient air for analysis of 14C of methane (14CH4)and other trace constituents. Paleoatmospheric 14CH4 measurements should constrain the fossil fraction of past methane budgets, as well as provide a definitive test of methane clathrate involvement in large and rapid methane concentration ([CH4]) increases that accompanied rapid warming events during the last deglaciation. Air dating to the Younger Dryas–Preboreal and Oldest Dryas–Bølling abrupt climatic transitions was obtained by melt extraction from old glacial ice outcropping at an ablation margin in West Greenland. The outcropping ice and occluded air were dated using a combination of δ15N of N2, δ18O of O2, δ18Oice and [CH4] measurements. The [CH4] blank of the melt extractions was <4 ppb. Measurements of δ18O and δ15N indicated no significant gas isotopic fractionation from handling. Measured Ar/N2, CFC-11 and CFC-12 in the samples indicated no significant contamination from ambient air. Ar/N2, Kr/Ar and Xe/Ar ratios in the samples were used to quantify effects of gas dissolution during the melt extractions and correct the sample [CH4]. Corrected [CH4] is elevated over expected values by up to 132 ppb for most samples, suggesting some in situ CH4 production in ice at this site.
Consecutive, adult, non–intensive care unit (non-ICU) inpatients triggering an institutional clinical sepsis pathway from May to August 2015.
All patients reviewed by an ID Fellow within 24 hours of sepsis pathway trigger underwent case review and clinic file documentation of recommendations. Those not reviewed by an ID Fellow were considered controls and received standard sepsis pathway care. The primary outcome was antibiotic appropriateness 48 hours after sepsis trigger.
In total, 164 patients triggered the sepsis pathway: 6 patients were excluded (previous sepsis trigger); 158 patients were eligible; 106 had ID intervention; and 52 were control cases. Of these 158 patients, 91 (58%) had sepsis, and 15 of these 158 (9.5%) had severe sepsis. Initial antibiotic appropriateness, assessable in 152 of 158 patients, was appropriate in 80 (53%) of these 152 patients and inappropriate in 72 (47%) of these patients. In the intervention arm, 93% of ID Fellow recommendations were followed or partially followed, including 53% of cases in which antibiotics were de-escalated. ID Fellow intervention improved antibiotic appropriateness at 48 hours by 24% (adjusted risk ratio, 1.24; 95% confidence interval, 1.04–1.47; P=.035). The appropriateness agreement among 3 blinded ID staff opinions was 95%. Differences in intervention and control group mortality (13% vs 17%) and median length of stay (13 vs 17.5 days) were not statistically significant.
Sepsis overdiagnosis and delayed antibiotic optimization may reduce sepsis pathway effectiveness. Early ID AMS improved antibiotic management of non-ICU inpatients with suspected sepsis, predominantly by de-escalation. Further studies are needed to evaluate clinical outcomes.
We reflect on the major issues raised by a thoughtful and diverse set of commentaries on our target article. We draw attention to the need to differentiate between ultimate and proximate explanation; the insurance hypothesis (IH) needs to be understood as an ultimate-level argument, although we welcome the various suggestions made about proximate mechanisms. Much of this response is concerned with clarifying the interrelationships between adaptationist explanations like the IH, constraint explanations, and dysfunction explanations, in understanding obesity. We also re-examine the empirical evidence base, concurring that it is equivocal and only partially supportive. Several commentators offer additional supporting evidence, whereas others propose alternative explanations for the evidence we reviewed and suggest ways that our current knowledge could be strengthened. Finally, we take the opportunity to clarify some of the assumptions and predictions of our formal model.
Integrative explanations of why obesity is more prevalent in some sectors of the human population than others are lacking. Here, we outline and evaluate one candidate explanation, the insurance hypothesis (IH). The IH is rooted in adaptive evolutionary thinking: The function of storing fat is to provide a buffer against shortfall in the food supply. Thus, individuals should store more fat when they receive cues that access to food is uncertain. Applied to humans, this implies that an important proximate driver of obesity should be food insecurity rather than food abundance per se. We integrate several distinct lines of theory and evidence that bear on this hypothesis. We present a theoretical model that shows it is optimal to store more fat when food access is uncertain, and we review the experimental literature from non-human animals showing that fat reserves increase when access to food is restricted. We provide a meta-analysis of 125 epidemiological studies of the association between perceived food insecurity and high body weight in humans. There is a robust positive association, but it is restricted to adult women in high-income countries. We explore why this could be in light of the IH and our theoretical model. We conclude that although the IH alone cannot explain the distribution of obesity in the human population, it may represent a very important component of a pluralistic explanation. We also discuss insights it may offer into the developmental origins of obesity, dieting-induced weight gain, and anorexia nervosa.
As Canada’s population ages, frailty – with its increased risk of functional decline, deterioration in health status, and death – will become increasingly common. The physiology of frailty reflects its multisystem, multi-organ origins. About a quarter of Canadians over age 65 are frail, increasing to over half in those older than 85. Our health care system is organized around single-organ systems, impairing our ability to effectively treat people having multiple disorders and functional limitations. To address frailty, we must recognize when it occurs, increase awareness of its significance, develop holistic models of care, and generate better evidence for its treatment. Recognizing how frailty impacts lifespan will allow for integration of care goals into treatment options. Different settings in the Canadian health care system will require different strategies and tools to assess frailty. Given the magnitude of challenges frailty poses for the health care system as currently organized, policy changes will be essential.
The subsurface exploration of other planetary bodies can be used to unravel their geological history and assess their habitability. On Mars in particular, present-day habitable conditions may be restricted to the subsurface. Using a deep subsurface mine, we carried out a program of extraterrestrial analog research – MINe Analog Research (MINAR). MINAR aims to carry out the scientific study of the deep subsurface and test instrumentation designed for planetary surface exploration by investigating deep subsurface geology, whilst establishing the potential this technology has to be transferred into the mining industry. An integrated multi-instrument suite was used to investigate samples of representative evaporite minerals from a subsurface Permian evaporite sequence, in particular to assess mineral and elemental variations which provide small-scale regions of enhanced habitability. The instruments used were the Panoramic Camera emulator, Close-Up Imager, Raman spectrometer, Small Planetary Linear Impulse Tool, Ultrasonic drill and handheld X-ray diffraction (XRD). We present science results from the analog research and show that these instruments can be used to investigate in situ the geological context and mineralogical variations of a deep subsurface environment, and thus habitability, from millimetre to metre scales. We also show that these instruments are complementary. For example, the identification of primary evaporite minerals such as NaCl and KCl, which are difficult to detect by portable Raman spectrometers, can be accomplished with XRD. By contrast, Raman is highly effective at locating and detecting mineral inclusions in primary evaporite minerals. MINAR demonstrates the effective use of a deep subsurface environment for planetary instrument development, understanding the habitability of extreme deep subsurface environments on Earth and other planetary bodies, and advancing the use of space technology in economic mining.
Many older adults experience what is clinically recognised as frailty but little is known about the perceptions of, and attitudes regarding, being frail. This qualitative study explored adults' perceptions of frailty and their beliefs concerning its progression and consequences. Twenty-nine participants aged 66–98 with varying degrees of frailty, residing either in their homes or institutional settings, participated in semi-structured interviews. Verbatim transcripts were analysed using a Grounded Theory approach. Self-identifying as ‘frail’ was perceived by participants to be strongly related to their own levels of health and engagement in social and physical activity. Being labelled by others as ‘old and frail’ contributed to the development of a frailty identity by encouraging attitudinal and behavioural confirmation of it, including a loss of interest in participating in social and physical activities, poor physical health and increased stigmatisation. Using both individual and social context, different strategies were used to resist self-identification. The study provides insights into older adults' perceptions and attitudes regarding frailty, including the development of a frailty identity and its relationship with activity levels and health. The implications of these findings for future research and practice are discussed.
Point-of-care ultrasound (PoCUS) has become an essential skill in the practice of emergency medicine (EM). Various EM residency programs now require competency in basic PoCUS applications. The education literature suggests that deliberate practice is necessary for skill acquisition and mastery. We used an educational theory, Ericsson’s model of deliberate practice, to create a PoCUS curriculum for our Royal College of Physicians and Surgeons of Canada EM residency.
Although international recommendations around curriculum requirements exist, this will be one of the first papers to describe the implementation of a specific PoCUS training program. This paper details the features of the program and lessons learned during its initial 3 years. Sharing this experience may serve as a nidus for scholarly discussion around how to best approach medical education in this area.
The Comprehensive Geriatric Assessment (CGA) is used in geriatric medicine as a means to manage the health care needs of older adults and to grade frailty. We modified the CGA so that it could be completed independently by care partners (usually family) and be used to grade frailty. Our objective was to examine the feasibility of a care partner completing the CGA at the time of the first prehospital encounter.
A prospective, observational study was conducted with a convenience sample of patients ≥ 70 years accompanied by a knowledgeable care partner. Feasibility was measured by the time required and percent completeness of items on the form based on completion by the care partner and by paramedic perception of utility.
Subjects (N 5 104) were enrolled with three postenrolment exclusions due to ineligibility. Most participants were older women living in their own home. The mean time to complete the questionnaire was 18.7 minutes (SD 11.3; median 15 minutes; interquartile range 12-20 minutes). Only 64% of the care partners recorded the time it took. Nineteen percent of paramedics completed a follow-up survey, and all felt screening for frailty was worthwhile and most (> 70%) thought that the CP-CGA may be a useful approach. The study was limited by recruitment bias of potentially eligible patients, a high level of missingness in the outcome measures of interest, and low paramedic participation rates.
We observed a high rate of item completeness of questionnaires with a mean time to complete of 18.7 minutes in a convenience sample of older patients. A small sample of paramedics universally endorsed the utility of screening for frailty in the prehospital setting, and many thought the CP-CGA was a helpful tool.
It is unknown whether there are racial differences in the heritability of major depressive disorder (MDD) because most psychiatric genetic studies have been conducted in samples comprised largely of white non-Hispanics. To examine potential differences between African-American (AA) and European-American (EA) young adult women in (1) Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) MDD prevalence, symptomatology, and risk factors, and (2) genetic and/or environmental liability to MDD, we analyzed data from a large population-representative sample of twins ascertained from birth records (n = 550 AA and n = 3226 EA female twins) aged 18–28 years at the time of MDD assessment by semi-structured psychiatric interview. AA women were more likely to have MDD risk factors; however, there were no significant differences in lifetime MDD prevalence between AA and EA women after adjusting for covariates (odds ratio = 0.88, 95% confidence interval [CI]: 0.67–1.15). Most MDD risk factors identified among AA women were also associated with MDD at similar magnitudes among EA women. Although the MDD heritability point estimate was higher among AA women than EA women in a model with paths estimated separately by race (56%, 95% CI: 29–78% vs. 41%, 95% CI: 29–52%), the best fitting model was one in which additive genetic and non-shared environmental paths for AA and EA women were constrained to be equal (A = 43%, 33–53% and E = 57%, 47–67%). In spite of a marked elevation in the prevalence of environmental risk exposures related to MDD among AA women, there were no significant differences in lifetime prevalence or heritability of MDD between AA and EA young women.
Ceremonial architecture of late precontact (A.D. 600-1500) societies of Puerto Rico consists of stone-lined plazas and ball courts (bateys,). Archaeologists use these structures to signify the onset of hierarchical “chiefly” polities and to interpret their regional organization. Problematically, little consideration is given to the costs of their physical construction and the associated organizational implications at local and regional scales. In this paper, we use data gathered through geoarchaeological field investigations to develop labor estimates for the plaza and bateys at the site of Tibes—one of the largest precolumbian ceremonial centers in Puerto Rico. The estimates provide a basis for addressing how these features were constructed at the site and are considered within the broader organizational contexts of incipient polities in the island's south-central region between A.D. 600 and A.D. 1200.
Aspects of disordered eating and personality traits, such as neuroticism, are correlated and individually heritable. We examined the phenotypic correlation between binge eating episodes and indices of personality (neuroticism, extraversion, openness to experience, agreeableness, conscientiousness, and control/impulsivity). For correlations ≥|0.20|, we estimated the extent to which genetic and environmental factors contributed to this correlation. Participants included 3,446 European American same-sex female twins from the Missouri Adolescent Female Twin Study (median age = 22 years). Binge eating episode was assessed via interview questions. Personality traits were assessed by self-report questionnaires. There was a significant moderate phenotypic correlation between binge eating episode and neuroticism (r = 0.33) as well as conscientiousness (r = -0.21), while other correlations were significant but smaller (r ranging from -0.14 to 0.14). Individual differences in binge eating episodes, neuroticism, and conscientiousness were attributed to additive genetic influences (38% [95% CI: 21–53%], 45% [95% CI: 38–52%], and 44% [95% CI: 0.33–0.55%] respectively), with the remaining variance attributed to individual-specific environmental influences. Covariance was attributable to genetic (neuroticism rg = 0.37; conscientiousness rg = -0.22) and individual-specific environmental (neuroticism re = 0.28; conscientiousness re = -0.19) influences. Personality traits may be an early indicator of genetic vulnerability to a variety of pathological behaviors, including binge eating episode. Furthermore, prior research documenting phenotypic correlations between eating disorder diagnoses and personality may have stemmed from etiological overlap between these personality traits and aspects of disordered eating, such as binge eating episode.