Ewen M Harrison

Ewen M Harrison
The University of Edinburgh | UoE · Centre for Medical Informatics

MB ChB, PhD, FRCS

About

414
Publications
137,807
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12,227
Citations
Additional affiliations
January 2004 - December 2012
The University of Edinburgh
October 2002 - present
The University of Edinburgh
Position
  • Pharmacological strategies to reduce ischemia reperfusion in organ transplantation

Publications

Publications (414)
Preprint
Full-text available
Optimising statistical power in early-stage trials and observational studies accelerates discovery and improves the reliability of results. Ideally, intermediate outcomes should be continuously distributed and lie on the causal pathway between an intervention and a definitive outcome such as mortality. In order to optimise power for an intermediate...
Preprint
Full-text available
Background Most studies of immunity to SARS-CoV-2 focus on circulating antibody, giving limited insights into mucosal defences that prevent viral replication and onward transmission. We studied nasal and plasma antibody responses one year after hospitalisation for COVID-19, including a period when SARS-CoV-2 vaccination was introduced. Methods Plas...
Preprint
Background Immunocompromised patients may be at higher risk of mortality if hospitalised with COVID-19 compared with immunocompetent patients. However, previous studies have been contradictory. We aimed to determine whether immunocompromised patients were at greater risk of in-hospital death, and how this risk changed over the pandemic. Methods We...
Article
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Background The number of individuals recovering from severe COVID-19 is increasing rapidly. However, little is known about physical behaviours that make up the 24-h cycle within these individuals. This study aimed to describe physical behaviours following hospital admission for COVID-19 at eight months post-discharge including associations with acu...
Article
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Malnutrition is an independent predictor for postoperative complications in low- and middle-income countries (LMICs). We systematically reviewed evidence on the impact of preoperative oral nutrition supplementation (ONS) on patients undergoing gastrointestinal cancer surgery in LMICs. We searched EMBASE, Cochrane Library, Web of Science, Scopus, WH...
Article
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Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a...
Preprint
Background Whilst timely clinical characterisation of infections caused by novel SARS-CoV-2 variants is necessary for evidence-based policy response, individual-level data on infecting variants are typically only available for a minority of patients and settings. Methods Here, we propose an innovative approach to study changes in COVID-19 hospital...
Article
Background: Data on interventions to reduce postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD) are conflicting. The aim of this study was to assimilate data from RCTs. Methods: MEDLINE and Embase databases were searched systematically for RCTs evaluating interventions to reduce all grades of POPF or clinically relevant...
Article
Full-text available
Heide A Stirnadel-Farrant,1 George Mu,2 Selin Cooper-Blenkinsopp,1 Rosemary O Schroyer,3 Kevin S Thorneloe,4 Ewen M Harrison,5 Susan MS Andrews6 1Department of WorldWide Epidemiology, GlaxoSmithKline, London, UK; 2Department of Data, Methods, and Analytics, GlaxoSmithKline, Collegeville, PA, USA; 3Department of Biostatistics, GlaxoSmithKline, Colle...
Article
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Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and proces...
Article
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Admission procalcitonin measurements and microbiology results were available for 1040 hospitalized adults with coronavirus disease 2019 (from 48 902 included in the International Severe Acute Respiratory and Emerging Infections Consortium World Health Organization Clinical Characterisation Protocol UK study). Although procalcitonin was higher in ba...
Article
Admission procalcitonin measurements and microbiology results were available for 1040 hospitalized adults with coronavirus disease 2019 (from 48 902 included in the International Severe Acute Respiratory and Emerging Infections Consortium World Health Organization Clinical Characterisation Protocol UK study). Although procalcitonin was higher in ba...
Article
Full-text available
COVID-19 is clinically characterised by fever, cough, and dyspnoea. Symptoms affecting other organ systems have been reported. However, it is the clinical associations of different patterns of symptoms which influence diagnostic and therapeutic decision-making. In this study, we applied clustering techniques to a large prospective cohort of hospita...
Article
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Background There are currently no effective pharmacological or non-pharmacological interventions for Long-COVID. We aimed to describe recovery one year after hospital discharge for COVID-19 and identify factors associated with patient-perceived recovery. To identify potential therapeutic targets, we focussed on previously described four recovery cl...
Article
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Background No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the...
Article
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Following the publication of the original article [1], we were notified that due to a misunderstanding during proofing, the authoring collaborator’s group was tagged as an affiliation instead of the main author. The original article has been corrected.
Article
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Background Dexamethasone was the first intervention proven to reduce mortality in patients with COVID-19 being treated in hospital. We aimed to evaluate the adoption of corticosteroids in the treatment of COVID-19 in the UK after the RECOVERY trial publication on June 16, 2020, and to identify discrepancies in care. Methods We did an audit of clin...
Article
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Background We hypothesised that the clinical characteristics of hospitalised children and young people (CYP) with SARS-CoV-2 in the UK second wave (W2) would differ from the first wave (W1) due to the alpha variant (B.1.1.7), school reopening and relaxation of shielding. Methods Prospective multicentre observational cohort study of patients <19 ye...
Preprint
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Background The effect of SARS-CoV-2 infection upon HPB cancer surgery perioperative outcomes is unclear. Establishing risk is key to individualizing treatment pathways. Aim To identify the mortality rate and complications risk for HPB cancer elective surgery during the pandemic. Methods International,prospective,multi center study of consecutive...
Article
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Introduction The postoperative period represents a time where patients are at a high-risk of morbidity, which warrants effective surveillance. While digital health interventions (DHIs) for postoperative monitoring are promising, a coordinated, standardized and evidence-based approach regarding their implementation and evaluation is currently lackin...
Article
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Background The effect of SARS-CoV-2 infection upon HPB cancer surgery perioperative outcomes is unclear. Establishing risk is key to individualising treatment pathways. Aim Identify the mortality rate and complications risk for HPB cancer elective surgery during the pandemic. Methods International, prospective, multicentre study of consecutive ad...
Article
Background The complexity of pancreaticoduodenectomy and fear of morbidity, particularly postoperative pancreatic fistula, can be a barrier to surgical trainees gaining operative experience. This meta-analysis sought to compare the postoperative pancreatic fistula rate after pancreatoenteric anastomosis by trainees or established surgeons. Methods...
Article
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Preoperative undernutrition is a prognostic indicator for postoperative mortality and morbidity. Evidence suggests that treating undernutrition can improve surgical outcomes. This study explored the provision of nutritional screening, assessment and support on surgical cancer wards in low- and middle-income countries (LMICs). This was a qualitative...
Article
Background Postoperative acute kidney injury (AKI) is a common complication of major gastrointestinal surgery with an impact on short- and long-term survival. No validated system for risk stratification exists for this patient group. This study aimed to validate externally a prognostic model for AKI after major gastrointestinal surgery in two multi...
Article
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word count: 250 Manuscript word count: 3402 Abbreviated running title: Severe COVID-19 Cohort. Potential Conflict of interest: Attached. Take home message: Countries and hospitals need to identify strategies to increase their ICU capacity (i.e., trained personnel, ICU beds and monitoring systems) to treat patients presenting to the hospital with se...
Article
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Background Acute kidney injury (AKI) is common in coronavirus disease 2019 (COVID-19). This study investigated adults hospitalized with COVID-19 and hypothesized that risk factors for AKI would include comorbidities and non-White race. Methods A prospective multicentre cohort study was performed using patients admitted to 254 UK hospitals with COVI...
Article
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Background Existing emergency general surgery (EGS) guidelines rarely include evidence from low- and middle-income countries (LMICs) and may lack relevance to low-resource settings. The aim of this study was to develop global guidelines for EGS that are applicable across all hospitals and health systems. Methods A systematic review and thematic an...
Preprint
Full-text available
Background There are currently no effective pharmacological or non-pharmacological interventions for Long-COVID. To identify potential therapeutic targets, we focussed on previously described four recovery clusters five months after hospital discharge, their underlying inflammatory profiles and relationship with clinical outcomes at one year. Metho...
Conference Paper
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Background Medical students have an essential role in medical research, yet often feel unprepared and lack opportunities for involvement as recruiters within research studies. This study aimed to understand the educational effect of involvement in clinical trial recruitment on medical students, and to derive generalisable future recommendations. M...
Article
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Due to the large number of patients with severe COVID-19, many were treated outside of the traditional walls of the ICU, and in many cases, by personnel who were not trained in critical care. The clinical characteristics and the relative impact of caring for severe COVID-19 patients outside of the ICU is unknown. This was a multinational, multicent...
Article
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Background Predicting bed occupancy for hospitalised patients with COVID-19 requires understanding of length of stay (LoS) in particular bed types. LoS can vary depending on the patient’s “bed pathway” - the sequence of transfers of individual patients between bed types during a hospital stay. In this study, we characterise these pathways, and thei...
Article
Purpose: To prospectively validate two risk scores to predict mortality (4C Mortality) and in-hospital deterioration (4C Deterioration) among adults hospitalised with COVID-19. Methods: Prospective observational cohort study of adults (age ≥18 years) with confirmed or highly suspected COVID-19 recruited into the International Severe Acute Respir...
Article
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Surgical site infections (SSI) cause substantial morbidity and pose a burden to acute healthcare services after surgery. We aimed to investigate whether a smartphone-delivered wound assessment tool can expedite diagnosis and treatment of SSI after emergency abdominal surgery. This single-blinded randomised control trial (NCT02704897) enroled adult...
Article
Background Multiple risk scores claim to predict the probability of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy. However, it is unclear which scores have undergone external validation, and which score is the most accurate. Objective To identify risk scores for POPF, and assess the clinical validity of these scores. Methods...
Article
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Complications following surgery are common and frequently occur the following discharge. Mobile and wearable digital health interventions (DHI) provide an opportunity to monitor and support patients during their postoperative recovery. Lack of high-quality evidence is often cited as a barrier to DHI implementation. This review captures and appraise...
Article
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Background We aimed to compare the prevalence and severity of fatigue in survivors of Covid-19 versus non-Covid-19 critical illness, and to explore potential associations between baseline characteristics and worse recovery. Methods We conducted a secondary analysis of two prospectively collected datasets. The population included was 92 patients wh...
Article
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Objectives We investigated the association between multimorbidity among patients hospitalised with COVID-19 and their subsequent risk of mortality. We also explored the interaction between the presence of multimorbidity and the requirement for an individual to shield due to the presence of specific conditions and its association with mortality. De...
Article
Full-text available
Background Acute kidney injury (AKI) is common in COVID-19. This study investigated adults hospitalised with COVID-19 and hypothesised that risk factors for AKI would include co-morbidities and non-white race. Methods A prospective multicentre cohort study was performed using patients admitted to 254 UK hospitals with COVID-19 between January 17th...
Article
Background & Aims Genome-wide association studies (GWAS) have identified several risk loci for gallstone disease. As with most polygenic traits, it is likely many genetic determinants are undiscovered. The aim of this study was to identify novel genetic variants, representing new targets for gallstone research and treatment. Approach & Results We...
Article
Aim Early death after cancer surgery is higher in low- and middle-income settings, yet the impact of hospital characteristics on early postoperative outcomes following cancer surgery worldwide are unknown. Method A mixed-methods analysis was performed using data from the GlobalSurg 3 study, a multicentre, international prospective cohort study of...
Article
Aim Gallstones have a prevalence of 20-40% in European populations and cause significant morbidity. Gallstones form from cholesterol and calcium bilirubinate and knowledge of genetic determinants remains incomplete. A genome-wide association study (GWAS) was performed to identify determinants of gallstones. Method A GWAS of 16,356,211 single nucle...
Preprint
Full-text available
Objective Identifying phenotypes and pathology from free text is an essential task for clinical work and research. Natural language processing (NLP) is a key tool for processing free text at scale. Developing and validating NLP models requires labelled data. Labels are generated through time-consuming and repetitive manual annotation and are hard t...
Article
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Background: The impact of COVID-19 on physical and mental health and employment after hospitalisation with acute disease is not well understood. The aim of this study was to determine the effects of COVID-19-related hospitalisation on health and employment, to identify factors associated with recovery, and to describe recovery phenotypes. Methods...
Article
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Background: the impact of COVID-19 on physical and mental health and employment after hospitalisation with acute disease is not well understood. The aim of this study was to determine the effects of COVID-19-related hospitalisation on health and employment, to identify factors associated with recovery, and to describe recovery phenotypes. Methods:...
Article
Full-text available
Background: The impact of COVID-19 on physical and mental health and employment after hospitalisation with acute disease is not well understood. The aim of this study was to determine the effects of COVID-19-related hospitalisation on health and employment, to identify factors associated with recovery, and to describe recovery phenotypes. Methods:...
Article
Full-text available
Background The impact of COVID-19 on physical and mental health and employment after hospitalisation with acute disease is not well understood. The aim of this study was to determine the effects of COVID-19-related hospitalisation on health and employment, to identify factors associated with recovery, and to describe recovery phenotypes. Methods...
Article
Full-text available
Background The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruit...
Article
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Background Surgical site infection (SSI) is the most common postoperative complication worldwide. WHO guidelines to prevent SSI recommend alcoholic chlorhexidine skin preparation and fascial closure using triclosan-coated sutures, but called for assessment of both interventions in low-resource settings. This study aimed to test both interventions i...
Poster
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Title: Trials and tribulations: educational impact from student-led recruitment in a surgical trial. Aim: To understand the effect of and derive recommendations for the involvement of medical students in clinical trial recruitment. Methods: Tracking wound infection with smartphone technology (TWIST) was a randomised controlled trial enrolling adu...
Article
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The bat connection The heterogeneity of COVID-19 makes it challenging to predict the course of infection in an individual. Upon virus infection, interferons (IFNs) generate the initial signals for cellular defenses. Knowing that defects in IFN signaling are associated with more severe COVID-19, Wickenhagen et al . used IFN-stimulated gene expressio...
Article
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Inherited genetic factors can influence the severity of COVID-19, but the molecular explanation underpinning a genetic association is often unclear. Intracellular antiviral defenses can inhibit the replication of viruses and reduce disease severity. To better understand the antiviral defenses relevant to COVID-19, we used interferon-stimulated gene...
Preprint
Full-text available
Background Children and young people (CYP) were less affected than adults in the first wave of SARS-CoV-2 in the UK. We test the hypothesis that clinical characteristics of hospitalized CYP with SARS-CoV-2 in the UK second wave would differ from the first due to the combined impact of the alpha variant, school reopening and relaxation of shielding....
Article
Full-text available
Objectives To derive and validate risk prediction algorithms to estimate the risk of covid-19 related mortality and hospital admission in UK adults after one or two doses of covid-19 vaccination. Design Prospective, population based cohort study using the QResearch database linked to data on covid-19 vaccination, SARS-CoV-2 results, hospital admis...