Browsing by Author "Hill, Michael D."
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- ItemOpen AccessA Psychological Perspective on Image Interpretation in Acute Ischemic Stroke: Factors Affecting Non-Contrast CT ASPECTS Reliability(2018-06-27) Wilson, Alexis Terrin Connett; Menon, Bijoy K.; Demchuk, Andrew M.; Hill, Michael D.; Saposnik, GustavoThe Alberta Stroke Program Early CT Score (ASPECTS) is a semiquantitative scale to assess the extent of early ischemic changes on non-contrast CT in acute ischemic stroke patients. This is crucial for prognostication and treatment selection. Recent studies have revealed significant heterogeneity in reported measures of inter-rater reliability in ASPECTS, and this thesis aims to investigate the reasons underlying this phenomenon from the perspective of clinicians’ cognitive processes. First, this work explores relevant topics in the psychology of image interpretation and, on this psychological basis, proposes potential causes of inconsistent ASPECTS reliability. Possible strategies to improve clinicians’ inter- and intra-rater reliability are also discussed. The effect of image reading context variables and rater expertise on ASPECTS inter-rater reliability was then investigated. Raters of different experience levels scored ASPECTS on baseline non-contrast CT scans under three prior-information conditions (NCCT only, NCCT with access to clinical information, NCCT with access to clinical information and multiphase CT angiography) and three reading-context conditions (high/low ambient light, time pressure). The results indicate that these variables have the capacity to affect ASPECTS reliability. This work highlights the importance of acknowledging that medical image interpretation can be influenced by seemingly irrelevant external and internal factors like reading environment characteristics or physician-level variables. Giving more consideration to these variables in clinical and educational settings could improve the utility of tools like ASPECTS.
- ItemOpen AccessA scoping review of the globally available tools for assessing health research partnership outcomes and impacts(2023-12-22) Mrklas, Kelly J.; Boyd, Jamie M.; Shergill, Sumair; Merali, Sera; Khan, Masood; Moser, Cheryl; Nowell, Lorelli; Goertzen, Amelia; Swain, Liam; Pfadenhauer, Lisa M.; Sibley, Kathryn M.; Vis-Dunbar, Mathew; Hill, Michael D.; Raffin-Bouchal, Shelley; Tonelli, Marcello; Graham, Ian D.Abstract Background Health research partnership approaches have grown in popularity over the past decade, but the systematic evaluation of their outcomes and impacts has not kept equal pace. Identifying partnership assessment tools and key partnership characteristics is needed to advance partnerships, partnership measurement, and the assessment of their outcomes and impacts through systematic study. Objective To locate and identify globally available tools for assessing the outcomes and impacts of health research partnerships. Methods We searched four electronic databases (Ovid MEDLINE, Embase, CINAHL + , PsychINFO) with an a priori strategy from inception to June 2021, without limits. We screened studies independently and in duplicate, keeping only those involving a health research partnership and the development, use and/or assessment of tools to evaluate partnership outcomes and impacts. Reviewer disagreements were resolved by consensus. Study, tool and partnership characteristics, and emerging research questions, gaps and key recommendations were synthesized using descriptive statistics and thematic analysis. Results We screened 36 027 de-duplicated citations, reviewed 2784 papers in full text, and kept 166 studies and three companion reports. Most studies originated in North America and were published in English after 2015. Most of the 205 tools we identified were questionnaires and surveys targeting researchers, patients and public/community members. While tools were comprehensive and usable, most were designed for single use and lacked validity or reliability evidence. Challenges associated with the interchange and definition of terms (i.e., outcomes, impacts, tool type) were common and may obscure partnership measurement and comparison. Very few of the tools identified in this study overlapped with tools identified by other, similar reviews. Partnership tool development, refinement and evaluation, including tool measurement and optimization, are key areas for future tools-related research. Conclusion This large scoping review identified numerous, single-use tools that require further development and testing to improve their psychometric and scientific qualities. The review also confirmed that the health partnership research domain and its measurement tools are still nascent and actively evolving. Dedicated efforts and resources are required to better understand health research partnerships, partnership optimization and partnership measurement and evaluation using valid, reliable and practical tools that meet partners’ needs.
- ItemOpen AccessA Spatial Epidemiological Analysis of Stroke in Alberta, Canada, Using GIS.(2015-01-08) van Rheenen, Susan M.; Hill, Michael D.; Watson, Tim W.J.Stroke is the potentially devastating result of a sudden interruption of blood flow to the brain. It is a leading cause of death and disability world wide and incidence is expected to increase due to an aging population and increased prevalence in risk factors. Epidemiological research can enhance our understanding of stroke as a health problem in the population with respect to the extent of disease incidence and prevalence, the efficacy of health care delivery for stroke prevention and acute care, and to inform public health policy and planning. Geographic Information Systems (GIS) technology and spatial methods provide the means to store and retrieve spatially indexed health data, display the spatial information in maps, and conduct analyses examining health service delivery and utilization. The overall objective of this research is to enrich our current understanding of stroke as a health problem in the province of Alberta, Canada. This thesis is comprised of three studies. The first study utilized GIS-based methods and administrative datasets to identify and locate significant clusters of high and low rates of the major stroke types and in-hospital mortality. Important questions were raised regarding why regional differences exist and how disparities might be mitigated. The second study expanded upon the cluster analysis with an examination of associations between selected predictors and stroke and mortality hot and cold spots, mortality at the individual level, and recurrent stroke, using multivariable logistic regression. Distance from specialized stroke care was a significant predictor of index and recurrent stroke and mortality. EMS transport and Comprehensive Stroke Centre care significantly lowered the odds of stroke mortality. The third study employed spatial methods to evaluate the concordance of GIS predicted versus actual EMS ground transport times and to estimate the proportion of the Alberta population with potential and realized access to stroke care within critical time windows. GIS methods predicted ground transport time with reasonable accuracy and there was expanded access to stroke care over a 5-year time span. This research highlights the benefits of incorporating spatial methods and GIS in epidemiological research to elucidate how and to what extent place matters to health.
- ItemOpen AccessCerebral Small Vessel Disease: Cognitive Reserve and Mediators of Cognitive Decline(2021-09-24) Durrani, Romella; Smith, Eric E.; Ismail, Zahinoor; Hill, Michael D.; Monchi, Oury; Dukelow, Sean P.; Postuma, Ronald B.Background: Cerebral small vessel disease (CSVD) is the most common type of cerebrovascular disease that contributes to cognitive decline and dementia. However, persons with the same burden of CSVD often have different cognitive outcomes. Cognitive reserve, defined as the ability to tolerate or adapt to pathology, has been suggested to explain these variations. There are limited studies on cognitive reserve in CSVD, as most studies have focused on Alzheimer’s disease (AD). These studies have also focused on education as the proxy of cognitive reserve, with only a few studies looking at other proxies, such as occupation and leisure activities. Additionally, few studies of cognitive reserve have examined other measures of cerebrovascular disease, beyond white matter hyperintensities (WMH). Objectives: Determine whether cognitive reserve mitigates the deleterious effects of CSVD on cognition, and determine the degree to which cerebral amyloid angiopathy (CAA) biomarkers mediate the effects of CAA on cognition.Methods: Data were analyzed from four multicenter, cross-sectional cohorts. Measures of cerebrovascular disease included: brain infarcts, non-lacunar covert brain infarcts (CBI), WMH, vascular lesion burden, and CAA. Measures of cognitive reserve included: education, occupation, social involvement, physical activity, leisure physical activity, household income, marital status, height, stress, and multilingualism. CAA biomarkers included: WMH, cerebrovascular reactivity (CVR), peak width of skeletonized mean diffusivity (PSMD), mean cortical thickness, and mean cortical thickness in an AD meta-region of interest.Results: WMH, non-lacunar CBI, vascular lesion burden, and CAA were associated with lower cognition. Proxies of cognitive reserve were associated with higher cognition. However, cognitive reserve did not modify the association between CSVD and cognition. CVR, PSMD, and mean cortical thickness in regions typically affected by AD accounted for half of the effects of CAA on cognition; PSMD was the largest contributor.Conclusions: This forms the largest body of work on cognitive reserve within CSVD. Strategies to prevent CSVD-related cognitive decline and dementia include: 1) preventing CSVD, 2) enhancing cognitive reserve, thereby independently increasing cognition---however, this does not mitigate the deleterious effects of CSVD on cognition, and 3) in CAA, maintaining white matter integrity and restoring normal cerebrovascular reactivity.
- ItemOpen AccessCurrent practice and attitudes of stroke physicians towards rhythm-control therapy for stroke prevention: results of an international survey(2023-07-06) Jensen, Märit; Al-Shahi Salman, Rustam; Ng, G. A.; van der Worp, H. B.; Loh, Peter; Campbell, Bruce C. V.; Kalman, Jonathan M.; Hill, Michael D.; Sposato, Luciano A.; Andrade, Jason G.; Metzner, Andreas; Kirchhof, Paulus; Thomalla, GötzAbstract Background Patients with ischemic stroke and atrial fibrillation (AF) are at particularly high risk for recurrent stroke and cardiovascular events. Early rhythm control has been shown to be superior to usual care for the prevention of stroke and cardiovascular events for people with early AF. There are no data on the willingness to use rhythm control for patients with AF and acute ischemic stroke in clinical practice. Methods An online survey was carried out among stroke physicians to assess current practice and attitudes toward rhythm control in patients with AF and acute ischemic stroke between December 22nd 2021 and March 24th 2022. Results The survey was completed by 277 physicians including 237 from 15 known countries and 40 from unspecified countries. 79% (210/266) reported that they do not regularly apply treatment for rhythm control by ablation or antiarrhythmic drugs at all or only in small numbers (≤ 10%) of patients with AF and acute ischemic stroke. In those patients treated with rhythm-control therapy, antiarrhythmic drugs were used by the majority of respondents (89%), while only a minority reported using AF ablation (11%). 88% of respondents (221/250) stated that they would be willing to randomize patients with AF after acute ischemic stroke to either early rhythm control or usual care in a clinical trial. Conclusion Despite its potential benefit, few patients with AF and acute ischemic stroke appear to be treated with rhythm control, which may result from uncertainty regarding potential complications of antiarrhythmic therapy in patients with acute stroke. Together with recent data on the effectiveness of early rhythm control in patients with a history of stroke, these results call for a randomized clinical trial to assess the efficacy of early rhythm control in patients with acute ischemic stroke and AF.
- ItemOpen AccessDrip and Ship versus Mothership: Transportation and Treatment Strategies for Acute Ischemic Stroke Patients(2019-07-22) Holodinsky, Jessalyn Kathryn; Hill, Michael D.; Williamson, Tyler S.; Demchuk, Andrew M.; Patel, Alka B.Ischemic stroke with large vessel occlusion can be treated with alteplase and/or endovascular therapy. While endovascular therapy has been proven more effective than alteplase the administration of both treatments is highly time sensitive. There are geographic disparities in access to endovascular therapy. For patients outside the immediate vicinity of a hospital equipped to perform endovascular therapy it is unknown whether transport directly to an endovascular center for alteplase and endovascular therapy (mothership) or transport to the closest centre for immediate alteplase treatment followed by transfer to the endovascular center (drip-and-ship) will result in best patient outcomes. In this thesis, this is explored using theoretical conditional probability. Models were generated using existing data from clinical trials of stroke treatment, the accuracy of prehospital large vessel occlusion screening tools, and time from onset to stroke treatment (a function of both geography and hospital efficiency). The models were used to determine which strategy predicts the greatest probability of excellent outcome for stroke patients in several different scenarios. The optimal transport strategy is influenced by three different factors, the impact of which is summarized as follows from the perspective of the drip and ship approach. First, the most probable diagnosis of the patient. As the positive predictive value of the large vessel occlusion screening tool decreases the importance of the drip and ship model is appreciated. Second, the speed of treatment at the receiving hospitals. Fast treatment at thrombolysis centres is key for the drip and ship model to remain viable. Finally, the patient’s travel time to and between the different hospitals. As the distance between the thrombolysis and endovascular centre increases again the importance of the drip and ship model is realized. This thesis presents a novel way of conceptualizing the pre-hospital transport of suspected stroke patients. Decision-making for pre-hospital transport can be modelled using existing clinical trial data; these models can be dynamically adapted to changing realities. As the radius of superiority of the different transport strategy is context specific regional customization transport protocols for stroke patients is essential.
- ItemOpen AccessEvidence for the Appropriate Testing and Implementation of New Therapies for Intracerebral Hemorrhage in Canada(2012) Specogna, Adrian Vladimir; Hill, Michael D.; Patten, Scott B.
- ItemOpen AccessExpanding the evidence of endovascular treatment for acute ischemic stroke: patient–centered outcomes, population–level impact, and patients presenting with mild stroke symptoms(2020-10-06) Zerna, Anna Charlotte; Hill, Michael D.; Demchuck, Andrew M.; Rabi, Doreen M.Endovascular treatment (EVT) for anterior circulation acute ischemic stroke due to large‐vessel occlusion is the new standard of care resulting in reduced disability compared to medical treatment. Practice guidelines recommend the use of EVT but can only speak to the evidence provided by clinical trials and might not be appropriate when complex medical decisions need to consider the heterogeneity of patients in routine clinical care. Brought about by the limitations of the clinical trials, the work described in this doctoral thesis aimed to assess the long–term sustainability of efficacy of EVT, the utilization of post–stroke outcomes that are patient–centered and more meaningful to affected individuals, and the effectiveness of EVT in patient populations that have not been part of clinical trial cohorts. These are commonly older patients with comorbidities and patients presenting with mild stroke symptoms. The miFUNCTION scale was shown to display greater granularity in the mild to moderately–severe disability range post–stroke compared to the modified Rankin Scale and thus provide more insight into the patient's ability and capacity to engage in meaningful life roles after EVT. In a population–based analysis, adult patients undergoing EVT spent on average more than one week longer at home within the first 90 days compared with patients receiving medical treatment. Home‐time was used as a novel, health‐economic, and patient‐centered outcome. For patients presenting with mild symptoms, EVT resulted in similar 90–day outcomes compared to medical management despite an increased risk of neurological deterioration at 24 hours. Due to uncertainty regarding the risk–benefit–ratio, a well–designed clinical trial will need to establish how best to treat these patients. Overall, the work described here provides greater understanding of how the benefits and risks of EVT might vary across the population and differ from the rather homogenous patient cohort that has been assessed in the clinical trials. The results of this research will be meaningful to patients who experience acute ischemic strokes caused by large vessel occlusion and also aid with economic and regulatory decisions to more broadly offer and organize EVT across Alberta and beyond.
- ItemOpen AccessFactors Associated with Early Deterioration after Spontaneous Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis(Public Library of Science (PLoS), 2014-05-08) Adrian V. Specogna; Turin, Tanvir C.; Patten, Scott B.; Hill, Michael D.
- ItemOpen AccessFinal 2 year results of the vascular imaging of acute stroke for identifying predictors of clinical outcome and recurrent ischemic eveNts (VISION) study(BioMed Central, 2011-04-23) Coutts, Shelagh B.; Hill, Michael D.; Eliasziw, Misha; Fischer, Karyn; Demchuk, Andrew M.
- ItemOpen AccessHow are health research partnerships assessed? A systematic review of outcomes, impacts, terminology and the use of theories, models and frameworks(2022-12-14) Mrklas, Kelly J.; Merali, Sera; Khan, Masood; Shergill, Sumair; Boyd, Jamie M.; Nowell, Lorelli; Pfadenhauer, Lisa M.; Paul, Kevin; Goertzen, Amelia; Swain, Liam; Sibley, Kathryn M.; Vis-Dunbar, Mathew; Hill, Michael D.; Raffin-Bouchal, Shelley; Tonelli, Marcello; Graham, Ian D.Abstract Background Accurate, consistent assessment of outcomes and impacts is challenging in the health research partnerships domain. Increased focus on tool quality, including conceptual, psychometric and pragmatic characteristics, could improve the quantification, measurement and reporting partnership outcomes and impacts. This cascading review was undertaken as part of a coordinated, multicentre effort to identify, synthesize and assess a vast body of health research partnership literature. Objective To systematically assess the outcomes and impacts of health research partnerships, relevant terminology and the type/use of theories, models and frameworks (TMF) arising from studies using partnership assessment tools with known conceptual, psychometric and pragmatic characteristics. Methods Four electronic databases were searched (MEDLINE, Embase, CINAHL Plus and PsycINFO) from inception to 2 June 2021. We retained studies containing partnership evaluation tools with (1) conceptual foundations (reference to TMF), (2) empirical, quantitative psychometric evidence (evidence of validity and reliability, at minimum) and (3) one or more pragmatic characteristics. Outcomes, impacts, terminology, definitions and TMF type/use were abstracted verbatim from eligible studies using a hybrid (independent abstraction–validation) approach and synthesized using summary statistics (quantitative), inductive thematic analysis and deductive categories (qualitative). Methodological quality was assessed using the Quality Assessment Tool for Studies with Diverse Designs (QATSDD). Results Application of inclusion criteria yielded 37 eligible studies. Study quality scores were high (mean 80%, standard deviation 0.11%) but revealed needed improvements (i.e. methodological, reporting, user involvement in research design). Only 14 (38%) studies reported 48 partnership outcomes and 55 impacts; most were positive effects (43, 90% and 47, 89%, respectively). Most outcomes were positive personal, functional, structural and contextual effects; most impacts were personal, functional and contextual in nature. Most terms described outcomes (39, 89%), and 30 of 44 outcomes/impacts terms were unique, but few were explicitly defined (9, 20%). Terms were complex and mixed on one or more dimensions (e.g. type, temporality, stage, perspective). Most studies made explicit use of study-related TMF (34, 92%). There were 138 unique TMF sources, and these informed tool construct type/choice and hypothesis testing in almost all cases (36, 97%). Conclusion This study synthesized partnership outcomes and impacts, deconstructed term complexities and evolved our understanding of TMF use in tool development, testing and refinement studies. Renewed attention to basic concepts is necessary to advance partnership measurement and research innovation in the field. Systematic review protocol registration: PROSPERO protocol registration: CRD42021137932 https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=137932 .
- ItemOpen AccessMachine learning models for functional impairment risk prediction in ischemic stroke patients(2020-09-03) Alaka, Shakiru Ayomide; Sajobi, Tolulope T.; Menon, Bijoy K.; Hill, Michael D.; Williamson, Tyler S.Background: Stroke-related functional impairment risk scores are commonly used to estimate the patient-specific risk of functional impairment in acute care settings. However, these models have been primarily developed based on regression models, which might not provide optimal predictive accuracy, especially when validated in an external cohort. Purpose: To evaluate the predictive accuracy of machine-learning (ML) models for predicting functional impairment risk in acute ischemic stroke patients. Second, to compare the predictive accuracy of machine-learning models and regression-based models using computer simulations. Methods: Using data from the Precise and Rapid Assessment of Collaterals with Multi-phase CT Angiography (PROVE-IT). The Modified Rankin Scale (mRS) score was used to assess the 90-day functional impairment status. The accuracy of machine-learning models such as random forest (RF), classification and regression tree (CART), support vector machine (SVM), C5.0 decision tree (DT), adaptive boost machine (ABM), and least absolute shrinkage and selection operator (LASSO) logistic regression, and logistic regression (LR) was used to predict the risk of patient-specific risk of 90-day functional impairment. Area under the receiver operating characteristic curve (AUC) sensitivity, specificity, Mathews correlation coefficient (MCC) and Brier score was used to assess the predictive accuracy of these models via internal cross-validation and external validation in the Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion with IVtPA Using Serial CT Angiography (INTERSSeCT) cohort study. Monte Carlo methods were used to develop recommendations for selecting machine-learning models under a variety of data characteristics. Results: Both logistic regression and machine-learning models had comparable predictive accuracy when validated internally (AUC range = [0.65 – 0.72]; MCC range = [0.29 - 0.42]) and externally (AUC range = [0.66 – 0.71]; MCC range = [0.34 – 0.42]). However, regression-based had a fairly better calibration than the ML models. Our simulation study showed that ML and regression-based models are not equally robust to a variety of data analytic characteristics. LR models exhibited higher AUC in studies with a small/moderate set of predictors, while RF had about 15% higher discrimination studies with high dimensional set of predictors. ML models may be less accurate for predicting outcomes in studies with a few sets of predictors or when there is a large class imbalance in the data sets. Conclusions ML and regression-based algorithms are not equally sensitive to data analytic conditions, even though our data analysis revealed no significant differences between the former and the latter. ML might offer some discriminative advantages over the latter depending on the size and type of study predictors. We recommend that the choice between these classes of models should be guided by data characteristics, study design, and purpose for which the models are being developed.
- ItemOpen AccessPassive Surveillance of Transient Ischemic Attacks in the Emergency Department: Validity of Administrative Data and Determinants of Inaccuracies in Data Coding(2016) Yu, Amy Y. X.; Hill, Michael D.; Coutts, Shelagh B.; Quan, Hude; McRae, Andrew D.Stroke is a leading cause of morbidity and transient ischemic attacks (TIA) are an ideal target for stroke prevention strategies. Administrative data are an important source of information for TIA research, but they have not been validated in the emergency department (ED). We aimed to determine the validity of TIA codes in the Canadian ED administrative database and the predictors of accurate TIA coding. We studied patients presenting to the ED with acute neurological symptoms. The National Ambulatory Care Reporting System (NACRS) database diagnosis codes were compared to the ED chart re-abstraction and 90-day final clinical diagnoses to obtain the sensitivity, specificity, and predictive values. The sensitivity of TIA codes was low to moderate (37-64%), but the specificity was high (82-93%). Quality of physician documentation was an important predictor of data accuracy. Our findings inform TIA research and surveillance methods and we identify an opportunity for improving administrative data quality.
- ItemOpen AccessThe Reliability and Sensitivity of the National Institutes of Health Stroke Scale for Spontaneous Intracerebral Hemorrhage in an Uncontrolled Setting(Public Library of Science, 2013-12-19) Specogna, Adrian V.; Patten, Scott B.; Turin, Tanvir C.; Hill, Michael D.
- ItemOpen AccessSurveillance Of Stroke Occurrence in the Calgary Health Region during 1995 - 2004(2008) Zhu, Haifeng; Hill, Michael D.
- ItemOpen AccessThe Brain in Motion II Study: study protocol for a randomized controlled trial of an aerobic exercise intervention for older adults at increased risk of dementia(2021-06-14) Krüger, Renata L.; Clark, Cameron M.; Dyck, Adrienna M.; Anderson, Todd J.; Clement, Fiona; Hanly, Patrick J.; Hanson, Heather M.; Hill, Michael D.; Hogan, David B.; Holroyd-Leduc, Jayna; Longman, R. S.; McDonough, Meghan; Pike, G. B.; Rawling, Jean M.; Sajobi, Tolulope; Poulin, Marc J.Abstract Background There remains no effective intervention capable of reversing most cases of dementia. Current research is focused on prevention by addressing risk factors that are shared between cardiovascular disease and dementia (e.g., hypertension) before the cognitive, functional, and behavioural symptoms of dementia manifest. A promising preventive treatment is exercise. This study describes the methods of a randomized controlled trial (RCT) that assesses the effects of aerobic exercise and behavioural support interventions in older adults at increased risk of dementia due to genetic and/or cardiovascular risk factors. The specific aims are to determine the effect of aerobic exercise on cognitive performance, explore the biological mechanisms that influence cognitive performance after exercise training, and determine if changes in cerebrovascular physiology and function persist 1 year after a 6-month aerobic exercise intervention followed by a 1-year behavioural support programme (at 18 months). Methods We will recruit 264 participants (aged 50–80 years) at elevated risk of dementia. Participants will be randomly allocated into one of four treatment arms: (1) aerobic exercise and health behaviour support, (2) aerobic exercise and no health behaviour support, (3) stretching-toning and health behaviour support, and (4) stretching-toning and no health behaviour support. The aerobic exercise intervention will consist of three supervised walking/jogging sessions per week for 6 months, whereas the stretching-toning control intervention will consist of three supervised stretching-toning sessions per week also for 6 months. Following the exercise interventions, participants will receive either 1 year of ongoing telephone behavioural support or no telephone support. The primary aim is to determine the independent effect of aerobic exercise on a cognitive composite score in participants allocated to this intervention compared to participants allocated to the stretching-toning group. The secondary aims are to examine the effects of aerobic exercise on a number of secondary outcomes and determine whether aerobic exercise-related changes persist after a 1-year behavioural support programme (at 18 months). Discussion This study will address knowledge gaps regarding the underlying mechanisms of the pro-cognitive effects of exercise by examining the potential mediating factors, including cerebrovascular/physiological, neuroimaging, sleep, and genetic factors that will provide novel biologic evidence on how aerobic exercise can prevent declines in cognition with ageing. Trial registration ClinicalTrials.gov NCT03035851 . Registered on 30 January 2017
- ItemOpen AccessThe Safety and Cost-Effectiveness of Carotid Angioplasty and Stenting in Calgary(2012-09-28) Almekhlafi, Mohammed; Hill, Michael D.Objectives To evaluate the safety and cost of carotid stenting in Calgary. Methods A cost-utility analysis from the perspective of the Canadian health care system was performed comparing stenting to endarterectomy using a decision analytic model. A prospective cohort study was done for trans cranial Doppler monitoring during stenting procedures. Findings were correlated with 24-hour MRI brain lesions using a binomial regression model. Results Stenting was more expensive than endarterectomy ($6106.84 incremental cost) and had a lower effectiveness (- 0.12 QALYs). Results were influenced by the procedure costs and were sensitive to patients’ characteristics. In 26 subjects who underwent stenting, MRI lesions were detected in 76%. Procedural monitoring showed a median of 224.5 emboli. Large emboli correlated with MRI lesions after adjusting for age and symptoms status. Conclusion To improve the outcomes of carotid stenting, research should aim to improve the procedure safety without increasing its costs.
- ItemOpen AccessThe unrestricted global effort to complete the COOL trial(2023-05-11) Kirkpatrick, Andrew W.; Coccolini, Federico; Tolonen, Matti; Minor, Samuel; Catena, Fausto; Gois, Emanuel; Doig, Christopher J.; Hill, Michael D.; Ansaloni, Luca; Chiarugi, Massimo; Tartaglia, Dario; Ioannidis, Orestis; Sugrue, Michael; Colak, Elif; Hameed, S. M.; Lampela, Hanna; Agnoletti, Vanni; McKee, Jessica L.; Garraway, Naisan; Sartelli, Massimo; Ball, Chad G.; Parry, Neil G.; Voght, Kelly; Julien, Lisa; Kroeker, Jenna; Roberts, Derek J.; Faris, Peter; Tiruta, Corina; Moore, Ernest E.; Ammons, Lee A.; Anestiadou, Elissavet; Bendinelli, Cino; Bouliaris, Konstantinos; Carroll, Rosemarry; Ceresoli, Marco; Favi, Francesco; Gurrado, Angela; Rezende-Neto, Joao; Isik, Arda; Cremonini, Camilla; Strambi, Silivia; Koukoulis, Georgios; Testini, Mario; Trpcic, Sandy; Pasculli, Alessandro; Picariello, Erika; Abu-Zidan, Fikri; Adeyeye, Ademola; Augustin, Goran; Alconchel, Felipe; Altinel, Yuksel; Hernandez Amin, Luz A.; Aranda-Narváez, José M.; Baraket, Oussama; Biffl, Walter L.; Baiocchi, Gian L.; Bonavina, Luigi; Brisinda, Giuseppe; Cardinali, Luca; Celotti, Andrea; Chaouch, Mohamed; Chiarello, Maria; Costa, Gianluca; de’Angelis, Nicola; De Manzini, Nicolo; Delibegovic, Samir; Di Saverio, Salomone; De Simone, Belinda; Dubuisson, Vincent; Fransvea, Pietro; Garulli, Gianluca; Giordano, Alessio; Gomes, Carlos; Hayati, Firdaus; Huang, Jinjian; Ibrahim, Aini F.; Huei, Tan J.; Jailani, Ruhi F.; Khan, Mansoor; Luna, Alfonso P.; Malbrain, Manu L. N. G.; Marwah, Sanjay; McBeth, Paul; Mihailescu, Andrei; Morello, Alessia; Mulita, Francesk; Murzi, Valentina; Mohammad, Ahmad T.; Parmar, Simran; Pak, Ajay; Wong, Michael P.; Pantalone, Desire; Podda, Mauro; Puccioni, Caterina; Rasa, Kemal; Ren, Jianan; Roscio, Francesco; Gonzalez-Sanchez, Antonio; Sganga, Gabriele; Scheiterle, Maximilian; Slavchev, Mihail; Smirnov, Dmitry; Tosi, Lorenzo; Trivedi, Anand; Vega, Jaime A. G.; Waledziak, Maciej; Xenaki, Sofia; Winter, Desmond; Wu, Xiuwen; Zakaria, Andee D.; Zakaria, ZaidiAbstract Background Severe complicated intra-abdominal sepsis (SCIAS) has an increasing incidence with mortality rates over 80% in some settings. Mortality typically results from disruption of the gastrointestinal tract, progressive and self-perpetuating bio-mediator generation, systemic inflammation, and multiple organ failure. A further therapeutic option may be open abdomen (OA) management with negative peritoneal pressure therapy (NPPT) to remove inflammatory ascites and attenuate the systemic damage from SCIAS, although there are definite risks of leaving the abdomen open whenever it might possibly be closed. This potential therapeutic paradigm is the rationale being assessed in the Closed Or Open after Laparotomy (COOL trial) ( https://clinicaltrials.gov/ct2/show/NCT03163095 ). Initially, the COOL trial received Industry sponsorship; however, this funding mandated the use of a specific trademarked and expensive NPPT device in half of the patients allocated to the intervention (open) arm. In August 2022, the 3 M/Acelity Corporation without consultation but within the terms of the contract canceled the financial support of the trial. Although creating financial difficulty, there is now no restriction on specific NPPT devices and removing a cost-prohibitive intervention creates an opportunity to expand the COOL trial to a truly global basis. This document describes the evolution of the COOL trial, with a focus on future opportunities for global growth of the study. Methods The COOL trial is the largest prospective randomized controlled trial examining the random allocation of SCIAS patients intra-operatively to either formal closure of the fascia or the use of the OA with an application of an NPPT dressing. Patients are eligible if they have free uncontained intraperitoneal contamination and physiologic derangements exemplified by septic shock OR severely adverse predicted clinical outcomes. The primary outcome is intended to definitively inform global practice by conclusively evaluating 90-day survival. Initial recruitment has been lower than hoped but satisfactory, and the COOL steering committee and trial investigators intend with increased global support to continue enrollment until recruitment ensures a definitive answer. Discussion OA is mandated in many cases of SCIAS such as the risk of abdominal compartment syndrome associated with closure, or a planned second look as for example part of “damage control”; however, improved source control (locally and systemically) is the most uncertain indication for an OA. The COOL trial seeks to expand potential sites and proceed with the evaluation of NPPT agnostic to device, to properly examine the hypothesis that this treatment attenuates systemic damage and improves survival. This approach will not affect internal validity and should improve the external validity of any observed results of the intervention. Trial registration: National Institutes of Health ( https://clinicaltrials.gov/ct2/show/NCT03163095 ).
- ItemOpen AccessTreatment surveillance, the baseline CT scan and a clinical prediction rule for prognosis in the thrombolytic treatment of actue ischemic stroke(2003) Hill, Michael D.; Ghali, William
- ItemEmbargoUnderstanding Stroke Rehabilitation Progression in a Robotic Rehabilitation Trial(2020-05-29) Keeling, Alexa Brianne; Dukelow, Sean P.; Cluff, Tyler; Hill, Michael D.Stroke is one of the leading causes of adult disability worldwide, leaving many individuals requiring rehabilitation to regain independence. A critical component to any rehabilitation program is progression, which is the ability of therapy program to change according to patient improvement. Currently, there is little known about therapy progression, which negatively impacts the optimization of rehabilitation programs. Therefore, the purpose of this thesis was to better understand how stroke survivor’s kinematics change throughout therapy in order to inform future rehabilitation programs. The first step in answering this question was to understand how motor learning contributes to recovery after stroke, which is explored in Chapter Two. Next, a therapy program was needed in order to study how stroke survivors progress during rehabilitation. The motor learning and stroke recovery principles discussed in Chapter Two were then used to inform the development of tasks for a robotic rehabilitation program for stroke survivors. The development, and subsequent testing, of the tasks are discussed in Chapter Three. It was found that this robotic therapy program was feasible after stroke and has the potential to improve clinical outcomes when compared only to standard of care. Using the results from this pilot study, the robotic therapy tasks were refined, as well as the study protocol, and gave rise to a Phase II Clinical Trial (RESTORE). As discussed in Chapter Four, subacute stroke patients were recruited to receive 20 days of robotic therapy for 1 or 2-hours a day, beginning either 5-9 days or 21-25 days post-stroke. Following completion of the intervention, changes in the participants’ kinematics measuring speed, accuracy, and smoothness of movements were examined. It was found that kinematics of directional error and hand path ratio (measures of accuracy), as well as smoothness, predominantly increased during the first 5 days of the intervention. Movement speed and percent time in target (a measure of accuracy), on the other hand, continued to improve throughout the intervention. These findings should be interpreted with caution due to small sample size but may be used to inform the progression of future robotic rehabilitation tasks.