Imperial College London

Professor the Lord Darzi of Denham PC KBE FRS FMedSci HonFREng

Faculty of MedicineDepartment of Surgery & Cancer

Professor of Surgery
 
 
 
//

Contact

 

+44 (0)20 3312 1310a.darzi

 
 
//

Location

 

Queen Elizabeth the Queen Mother Wing (QEQM)St Mary's Campus

//

Summary

 

Publications

Publication Type
Year
to

1500 results found

Ahmed I, Ahmad NS, Ali S, Ali S, George A, Saleem Danish H, Uppal E, Soo J, Mobasheri MH, King D, Cox B, Darzi Aet al., 2018, Medication Adherence Apps: Review and Content Analysis., JMIR Mhealth Uhealth, Vol: 6, ISSN: 2291-5222

BACKGROUND: Medication adherence is an expensive and damaging problem for patients and health care providers. Patients adhere to only 50% of drugs prescribed for chronic diseases in developed nations. Digital health has paved the way for innovative smartphone solutions to tackle this challenge. However, despite numerous apps available claiming to improve adherence, a thorough review of adherence apps has not been carried out to date. OBJECTIVE: The aims of this study were to (1) review medication adherence apps available in app repositories in terms of their evidence base, medical professional involvement in development, and strategies used to facilitate behavior change and improve adherence and (2) provide a system of classification for these apps. METHODS: In April 2015, relevant medication adherence apps were identified by searching the Apple App Store and the Google Play Store using a combination of relevant search terms. Data extracted included app store source, app price, documentation of health care professional (HCP) involvement during app development, and evidence base for each respective app. Free apps were downloaded to explore the strategies used to promote medication adherence. Testing involved a standardized medication regimen of three reminders over a 4-hour period. Nonadherence features designed to enhance user experience were also documented. RESULTS: The app repository search identified a total of 5881 apps. Of these, 805 fulfilled the inclusion criteria initially and were tested. Furthermore, 681 apps were further analyzed for data extraction. Of these, 420 apps were free for testing, 58 were inaccessible and 203 required payment. Of the 420 free apps, 57 apps were developed with HCP involvement and an evidence base was identified in only 4 apps. Of the paid apps, 9 apps had HCP involvement, 1 app had a documented evidence base, and 1 app had both. In addition, 18 inaccessible apps were produced with HCP involvement, whereas 2 apps had a documente

JOURNAL ARTICLE

Alkandari A, Ashrafian H, Sathyapalan T, Sedman P, Darzi A, Holmes E, Athanasiou T, Atkin SL, Gooderham NJet al., 2018, Improved physiology and metabolic flux after Roux-en-Y gastric bypass is associated with temporal changes in the circulating microRNAome: a longitudinal study in humans., BMC Obes, Vol: 5, ISSN: 2052-9538

Background: The global pandemic of obesity and the metabolic syndrome are leading causes of mortality and morbidity. Bariatric surgery leads to sustained weight loss and improves obesity-associated morbidity including remission of type 2 diabetes. MicroRNAs are small, endogenous RNAs that regulate gene expression post-transcriptionally, controlling most of the human transcriptome and contributing to the regulation of systemic metabolism. This preliminary, longitudinal, repeat sampling study, in which subjects acted as their own control, aimed to assess the temporal effect of bariatric surgery on circulating microRNA expression profiles. Methods: We used Exiqon's optimized circulating microRNA panel (comprising 179 validated miRNAs) and miRCURY locked nucleic acid plasma/serum Polymerase Chain Reaction (PCR) to assess circulating microRNA expression. The microRNAome was determined for Roux-en-Y gastric bypass (RYGB) patients examined preoperatively and at 1 month, 3 months, 6 months, 9 months and 12 months postoperatively. Data was analysed using multivariate and univariate statistics. Results: Compared to the preoperative circulating microRNA expression profile, RYGB altered the circulating microRNAome in a time dependent manner and the expression of 48 circulating microRNAs were significantly different. Importantly, these latter microRNAs are associated with pathways involved in regulation and rescue from metabolic dysfunction and correlated with BMI, the percentage of excess weight loss and fasting blood glucose levels. Conclusions: The results of this pilot study show that RYGB fundamentally alters microRNA expression in circulation with a time-dependent progressive departure in profile from the preoperative baseline and indicate that microRNAs are potentially novel biomarkers for the benefits of bariatric surgery.

JOURNAL ARTICLE

Appelbaum N, Clarke J, Maconochie I, Darzi Aet al., 2018, Paediatric weight estimation by age in the digital era: optimising a necessary evil, RESUSCITATION, Vol: 122, Pages: 29-35, ISSN: 0300-9572

JOURNAL ARTICLE

Appelbaum N, Clarke J, Maconochie I, Darzi Aet al., 2018, A model for habitus-adjusted paediatric weight estimation by age and data concerning the validation of this method on a large dataset of English children., Data Brief, Vol: 16, Pages: 771-774, ISSN: 2352-3409

It is often not possible to weigh children upon arrival at an emergency room before commencing the provision of emergency care. Because drugs for children are prescribed on the basis of age and body weight, estimations of weight are necessitated. Age-based equations have been one of the most commonly used weight estimation strategies historically. Due to the variability of weight for age in children, and variations in body habitus, these methods are inaccurate by design (Young and Korotzer, 2016) [1].

JOURNAL ARTICLE

Archer S, Pinto A, Vuik S, Bicknell C, Faiz O, Byrne B, Johnston M, Skapinakis P, Athanasiou T, Vincent C, Darzi Aet al., 2018, Surgery, Complications, and Quality of Life: A Longitudinal Cohort Study Exploring the Role of Psychosocial Factors., Ann Surg

OBJECTIVE: To determine whether psychosocial factors moderate the relationship between surgical complications and quality of life (QoL). BACKGROUND: Patients who experience surgical complications have significantly worse postoperative QoL than patients with an uncomplicated recovery. Psychosocial factors, such as coping style and level of social support influence how people deal with stressful events, but it is unclear whether they affect QoL following a surgical complication. These findings can inform the development of appropriate interventions that support patients postoperatively. METHODS: This is a longitudinal cohort study; data were collected pre-op, 1 month post-op, 4 months post-op, and 12 months post-op. A total of 785 patients undergoing major elective gastrointestinal, vascular, or cardiothoracic surgery who were recruited from 28 National Health Service sites in England and Scotland took part in the study. RESULTS: Patients who experience major surgical complications report significantly reduced levels of physical and mental QoL (P < 0.05) but they make a full recovery over time. Findings indicate that a range of psychosocial factors such as the use of humor as a coping style and the level of health care professional support may moderate the impact of surgical complications on QoL. CONCLUSIONS: Surgical complications alongside other sociodemographic and psychosocial factors contribute to changes in QoL; the results from this exploratory study suggest that interventions that increase the availability of healthcare professional support and promote more effective coping strategies before surgery may be useful, particularly in the earlier stages of recovery where QoL is most severely compromised. However, these relationships should be further explored in longitudinal studies that include other types of surgery and employ rigorous recruitment and follow-up procedures.

JOURNAL ARTICLE

Ashraf H, Sodergren MH, Merali N, Mylonas G, Singh H, Darzi Aet al., 2018, Eye-tracking technology in medical education: A systematic review, MEDICAL TEACHER, Vol: 40, Pages: 62-69, ISSN: 0142-159X

JOURNAL ARTICLE

Clift AK, Pawa N, Osmani H, Drymousis P, Cichocki A, Malczewska A, Faiz O, Wasan H, Kaltsas G, Darzi A, Cwikla J, Frilling Aet al., 2018, Appropriate Surgical Strategy in Appendiceal Neuroendocrine Tumors: Is Right Hemicolectomy Oncologically Justified or Overtreatment?, 15th Annual ENETS Conference for the Diagnosis and Treatment of Neuroendocrine Tumor Disease, Publisher: KARGER, Pages: 269-269, ISSN: 0028-3835

CONFERENCE PAPER

Darzi A, 2018, A British Perspective on the American College of Surgeons Conversation About Firearm Safety, ANNALS OF SURGERY, Vol: 267, Pages: 430-431, ISSN: 0003-4932

JOURNAL ARTICLE

Dewa LH, Murray K, Thibaut B, Ramtale SC, Adam S, Darzi A, Archer Set al., 2018, Identifying research priorities for patient safety in mental health: an international expert Delphi study., BMJ Open, Vol: 8

OBJECTIVE: Physical healthcare has dominated the patient safety field; research in mental healthcare is not as extensive but findings from physical healthcare cannot be applied to mental healthcare because it delivers specialised care that faces unique challenges. Therefore, a clearer focus and recognition of patient safety in mental health as a distinct research area is still needed. The study aim is to identify future research priorities in the field of patient safety in mental health. DESIGN: Semistructured interviews were conducted with the experts to ascertain their views on research priorities in patient safety in mental health. A three-round online Delphi study was used to ascertain consensus on 117 research priority statements. SETTING AND PARTICIPANTS: Academic and service user experts from the USA, UK, Switzerland, Netherlands, Ireland, Denmark, Finland, Germany, Sweden, Australia, New Zealand and Singapore were included. MAIN OUTCOME MEASURES: Agreement in research priorities on a five-point scale. RESULTS: Seventy-nine statements achieved consensus (>70%). Three out of the top six research priorities were patient driven; experts agreed that understanding the patient perspective on safety planning, on self-harm and on medication was important. CONCLUSIONS: This is the first international Delphi study to identify research priorities in safety in the mental field as determined by expert academic and service user perspectives. A reasonable consensus was obtained from international perspectives on future research priorities in patient safety in mental health; however, the patient perspective on their mental healthcare is a priority. The research agenda for patient safety in mental health identified here should be informed by patient safety science more broadly and used to further establish this area as a priority in its own right. The safety of mental health patients must have parity with that of physical health patients to achieve this.

JOURNAL ARTICLE

Dilley JWR, Hughes-Hallett A, Pratt PJ, Pucher PH, Camara M, Darzi AW, Mayer EKet al., 2018, Perfect Registration Leads to Imperfect Performance: A Randomized Trial of Multimodal Intraoperative Image Guidance., Ann Surg

OBJECTIVE: To compare surgical safety and efficiency of 2 image guidance modalities, perfect augmented reality (AR) and side-by-side unregistered image guidance (IG), against a no guidance control (NG), when performing a simulated laparoscopic cholecystectomy (LC). BACKGROUND: Image guidance using AR offers the potential to improve understanding of subsurface anatomy, with positive ramifications for surgical safety and efficiency. No intra-abdominal study has demonstrated any advantage for the technology. Perfect AR cannot be provided in the operative setting in a patient; however, it can be generated in the simulated setting. METHODS: Thirty-six experienced surgeons performed a baseline LC using the LapMentor simulator before randomization to 1 of 3 study arms: AR, IG, or NG. Each performed 3 further LC. Safety and efficiency-related simulator metrics, and task workload (SURG-TLX) were collected. RESULTS: The IG group had a shorter total instrument path length and fewer movements than NG and AR groups. Both IG and NG took a significantly shorter time than AR to complete dissection of Calot triangle. Use of IG and AR resulted in significantly fewer perforations and serious complications than the NG group. IG had significantly fewer perforations and serious complications than the AR group. Compared with IG, AR guidance was found to be significantly more distracting. CONCLUSION: Side-by-side unregistered image guidance (IG) improved safety and surgical efficiency in a simulated setting when compared with AR or NG. IG provides a more tangible opportunity for integrating image guidance into existing surgical workflow as well as delivering the safety and efficiency benefits desired.

JOURNAL ARTICLE

Erridge S, Ashraf H, Purkayastha S, Darzi A, Sodergren MHet al., 2018, Comparison of gaze behaviour of trainee and experienced surgeons during laparoscopic gastric bypass, BRITISH JOURNAL OF SURGERY, Vol: 105, Pages: 287-294, ISSN: 0007-1323

JOURNAL ARTICLE

Erridge S, Moussa O, Ziprin P, Purkayastha Set al., 2018, RISK OF GORD-RELATED DISORDERS IN OBESE PATIENTS ON PPI THERAPY: A POPULATION ANALYSIS, Annual Meeting of the Society-of-Academic-and-Research-Surgery (SARS), Publisher: WILEY, Pages: 18-18, ISSN: 0007-1323

CONFERENCE PAPER

Flott K, Darzi A, Gancarczyk S, Mayer Eet al., 2018, Improving the Usefulness and Use of Patient Survey Programs: National Health Service Interview Study, JOURNAL OF MEDICAL INTERNET RESEARCH, Vol: 20, ISSN: 1438-8871

JOURNAL ARTICLE

Garas G, Markar SR, Malietzis G, Ashrafian H, Hanna GB, Zacharakis E, Jiao LR, Argiris A, Darzi A, Athanasiou Tet al., 2018, Induced Bias Due to Crossover Within Randomized Controlled Trials in Surgical Oncology: A Meta-regression Analysis of Minimally Invasive versus Open Surgery for the Treatment of Gastrointestinal Cancer, ANNALS OF SURGICAL ONCOLOGY, Vol: 25, Pages: 221-230, ISSN: 1068-9265

JOURNAL ARTICLE

Gohil S, Vuik S, Darzi A, 2018, Sentiment Analysis of Health Care Tweets: Review of the Methods Used., JMIR Public Health Surveill, Vol: 4, ISSN: 2369-2960

BACKGROUND: Twitter is a microblogging service where users can send and read short 140-character messages called "tweets." There are several unstructured, free-text tweets relating to health care being shared on Twitter, which is becoming a popular area for health care research. Sentiment is a metric commonly used to investigate the positive or negative opinion within these messages. Exploring the methods used for sentiment analysis in Twitter health care research may allow us to better understand the options available for future research in this growing field. OBJECTIVE: The first objective of this study was to understand which tools would be available for sentiment analysis of Twitter health care research, by reviewing existing studies in this area and the methods they used. The second objective was to determine which method would work best in the health care settings, by analyzing how the methods were used to answer specific health care questions, their production, and how their accuracy was analyzed. METHODS: A review of the literature was conducted pertaining to Twitter and health care research, which used a quantitative method of sentiment analysis for the free-text messages (tweets). The study compared the types of tools used in each case and examined methods for tool production, tool training, and analysis of accuracy. RESULTS: A total of 12 papers studying the quantitative measurement of sentiment in the health care setting were found. More than half of these studies produced tools specifically for their research, 4 used open source tools available freely, and 2 used commercially available software. Moreover, 4 out of the 12 tools were trained using a smaller sample of the study's final data. The sentiment method was trained against, on an average, 0.45% (2816/627,024) of the total sample data. One of the 12 papers commented on the analysis of accuracy of the tool used. CONCLUSIONS: Multiple methods are used for sentiment analysis of tweets in the

JOURNAL ARTICLE

Hassen Y, Singh P, Pucher PH, Johnston MJ, Darzi Aet al., 2018, Identifying quality markers of a safe surgical ward: An interview study of patients, clinical staff, and administrators., Surgery, Vol: 163, Pages: 1226-1233

BACKGROUND: Postoperative care quality is variable. Risk-adjusted mortality rates differ between institutions despite comparable complication rates. This indicates that there are underlying factors rooted in how care is delivered that determines patient safety. This study aims to evaluate systematically the surgical ward environment with respect to process-driven and structural factors to identify quality markers for safe care, from which new safety metrics may be derived. METHODS: Semistructured interviews of clinicians, nurses, patients and administrators were undertaken for the study. RESULTS: In the study, 97% of staff members recognized the existence of variation in patient safety between surgical wards. Four main error-prone processes were identified: ward rounds (57%), medication prescribing and administration (49%), the presence of outliers (43%), and deficiencies in communication between clinical staff (43%). Structural factors were categorized as organizational or environmental; organizational included shortage in staffing (39%) and use of temporary staff (27%). Environmental factors considered layout and patient visibility to nurses (49%) as well as cleanliness (29%). Safety indicators identified included staff experience level (31%), overall layout of the ward, cleanliness and leadership (all 27% each). The majority of patients (87%) identified staff attentiveness as a safety indicator. CONCLUSION: This study demonstrates that there are a number of factors that may contribute to safety on the surgical ward spanning multiple processes, organizational, and environmental factors. Safety indicators identified across all these categories presents an opportunity to develop broader and more effectual safety improvement measures focusing on multiple areas simultaneously.

JOURNAL ARTICLE

Hassen YAM, Johnston MJ, Singh P, Pucher PH, Darzi Aet al., 2018, Key Components of the Safe Surgical Ward: International Delphi Consensus Study to Identify Factors for Quality Assessment and Service Improvement., Ann Surg

OBJECTIVE: The aim of this study was to prioritize key factors contributing to safety on the surgical ward BACKGROUND:: There is a variation in the quality and safety of postoperative care between institutions. These variations may be attributed to a combination of process-related issues and structural factors. The aim of this study is to reach a consensus, by means of Delphi methodology, on the most influential of these components that may determine safety in this environment. METHODS: The Delphi questionnaire was delivered via an online questionnaire platform. The panel were blinded. An international panel of safety experts, both clinical and nonclinical, and safety advocates participated. Individuals were selected according to their expertise and extent of involvement in patient safety research, regulation, or patient advocacy. RESULTS: Experts in patient safety from the UK, Europe, North America, and Australia participated. The panel identified the response to a deteriorating patient and the care of outlier patients as error-prone processes. Prioritized structural factors included organizational and environmental considerations such as use of temporary staff, out-of-hours reduction in services, ward cleanliness, and features of layout. The latter includes dedicated areas for medication preparation and adequate space around the patient for care delivery. Potential quality markers for safe care that achieved the highest consensus include leadership, visibility between patients and nurses, and nursing team skill mix and staffing levels. CONCLUSION: International consensus was achieved for a number of factors across process-related and structural themes that may influence safety in the postoperative environment. These should be championed and prioritized for future improvements in patient safety at the ward-level.

JOURNAL ARTICLE

Johnston MJ, Arora S, King D, Darzi Aet al., 2018, Improving the Quality of Ward-based Surgical Care With a Human Factors Intervention Bundle, ANNALS OF SURGERY, Vol: 267, Pages: 73-80, ISSN: 0003-4932

JOURNAL ARTICLE

Kwasnicki RM, Cross GW, Geoghegan L, Zhang Z, Reilly P, Darzi A, Yang GZ, Emery Ret al., 2018, A lightweight sensing platform for monitoring sleep quality and posture: a simulated validation study, EUROPEAN JOURNAL OF MEDICAL RESEARCH, Vol: 23, ISSN: 0949-2321

JOURNAL ARTICLE

Lami M, Singh H, Dilley JH, Ashraf H, Edmondon M, Orihuela-Espina F, Hoare J, Darzi A, Sodergren MHet al., 2018, Gaze patterns hold key to unlocking successful search strategies and increasing polyp detection rate in colonoscopy., Endoscopy

BACKGROUND: The adenoma detection rate (ADR) is an important quality indicator in colonoscopy. The aim of this study was to evaluate the changes in visual gaze patterns (VGPs) with increasing polyp detection rate (PDR), a surrogate marker of ADR. METHODS: 18 endoscopists participated in the study. VGPs were measured using eye-tracking technology during the withdrawal phase of colonoscopy. VGPs were characterized using two analyses - screen and anatomy. Eye-tracking parameters were used to characterize performance, which was further substantiated using hidden Markov model (HMM) analysis. RESULTS: Subjects with higher PDRs spent more time viewing the outer ring of the 3 × 3 grid for both analyses (screen-based: r = 0.56, P = 0.02; anatomy: r = 0.62, P < 0.01). Fixation distribution to the "bottom U" of the screen in screen-based analysis was positively correlated with PDR (r = 0.62, P = 0.01). HMM demarcated the VGPs into three PDR groups. CONCLUSION: This study defined distinct VGPs that are associated with expert behavior. These data may allow introduction of visual gaze training within structured training programs, and have implications for adoption in higher-level assessment.

JOURNAL ARTICLE

Malik HT, Marti J, Darzi A, Mossialos Eet al., 2018, Savings from reducing low-value general surgical interventions, BRITISH JOURNAL OF SURGERY, Vol: 105, Pages: 13-25, ISSN: 0007-1323

JOURNAL ARTICLE

Modi HN, Singh H, Orihuela-Espina F, Athanasiou T, Fiorentino F, Yang G-Z, Darzi A, Leff DRet al., 2018, Temporal Stress in the Operating Room: Brain Engagement Promotes "Coping" and Disengagement Prompts "Choking"., Ann Surg, Vol: 267, Pages: 683-691

OBJECTIVE: To investigate the impact of time pressure (TP) on prefrontal activation and technical performance in surgical residents during a laparoscopic suturing task. BACKGROUND: Neural mechanisms enabling surgeons to maintain performance and cope with operative stressors are unclear. The prefrontal cortex (PFC) is implicated due to its role in attention, concentration, and performance monitoring. METHODS: A total of 33 residents [Postgraduate Year (PGY)1-2 = 15, PGY3-4 = 8, and PGY5 = 10] performed a laparoscopic suturing task under "self-paced" (SP) and "TP" conditions (TP = maximum 2 minutes per knot). Subjective workload was quantified using the Surgical Task Load Index. PFC activation was inferred using optical neuroimaging. Technical skill was assessed using progression scores (au), error scores (mm), leak volumes (mL), and knot tensile strengths (N). RESULTS: TP led to greater perceived workload amongst all residents (mean Surgical Task Load Index score ± SD: PGY1-2: SP = 160.3 ± 24.8 vs TP = 202.1 ± 45.4, P < 0.001; PGY3-4: SP = 123.0 ± 52.0 vs TP = 172.5 ± 43.1, P < 0.01; PGY5: SP = 105.8 ± 55.3 vs TP = 159.1 ± 63.1, P < 0.05). Amongst PGY1-2 and PGY3-4, deterioration in task progression, error scores and knot tensile strength (P < 0.05), and diminished PFC activation was observed under TP. In PGY5, TP resulted in inferior task progression and error scores (P < 0.05), but preservation of knot tensile strength. Furthermore, PGY5 exhibited less attenuation of PFC activation under TP, and greater activation than either PGY1-2 or PGY3-4 under both experimental conditions (P < 0.05). CONCLUSIONS: Senior residents cope better with temporal demands and exhibit greater technical performance stability under pressure, possibly due to sustained PFC activation and greater task engagement. Future work should seek to develop training strategies that recruit prefrontal resources, enha

JOURNAL ARTICLE

Moussa O, Arhi C, Ziprin P, Darzi A, Khan O, Purkayastha Set al., 2018, Fate of the metabolically healthy obese-is this term a misnomer? A study from the Clinical Practice Research Datalink., Int J Obes (Lond)

INTRODUCTION: The metabolically healthy obese (MHO) phenotype may express typical characteristics on long-term follow-up. Little is known about the initiation of this phenotypes and its future stability. AIM: The Clinical Practice Research Datalink (CPRD) is a large-scale primary care database. The aim of this study was to assess the stability of, and evaluate the factors associated with a transition into an unhealthy outcome in, a MHO population in the UK. METHODS: The CPRD was interrogated for a diagnosis of 'obesity' and cross-referenced with a body mass index (BMI) ≥35 kg/m2; participants were further classified as MH using a clinical diagnostic code or a relative therapeutic code. A hazard cox regression univariate and multivariate analysis evaluated the time to transition for independent variables. RESULTS: There were 231,399 patients with a recorded BMI of 35 kg/m2 or greater. Incomplete records were eliminated and follow-up limited to 300 months, the cohort was reduced to 180,560 patients. The prevalence of MHO within the obese population from the CPRD was 128,191/180,560 (71%). MHO individuals, who were of male gender (hazard ratio (HR) 1.23 (1.21-1.25), p = < 0.01), older age group (HR 3.93 (3.82-4.04), p = < 0.01), BMI of 50-60 kg/m2 at baseline (HR 1.32(1.26-1.38), p = 0.01), smokers (HR 1.07(1.05-1.09), p = < 0.01) and regionally from North West England (HR 1.15(1.09-1.21), p = < 0.01) were more prone to an unhealthy transition (to develop comorbidities). Overall, of those MH at baseline, 71,485/128,191(55.8%) remained healthy on follow-up, with a mean follow-up of 113.5 (standard deviations (SD) 78.6) months or 9.4 (SD 6.6) years. CONCLUSIONS: From this unique large data set, there is a greater prevalence of MHO individuals in the UK population than in published literature elsewhere. Female gender, younger age group

JOURNAL ARTICLE

Moussa OM, Erridge S, Chidambaram S, Ziprin P, Darzi A, Purkayastha Set al., 2018, Mortality of the Severely Obese: A Population Study., Ann Surg

OBJECTIVE: This study aimed to analyze the Clinical Practice Research Datalink to identify the prognostic factors of all-cause mortality in the severely obese. BACKGROUND: Patients who are severely obese [body mass index (BMI) ≥35 kg/m] are at increased risk of all-cause mortality as a result of metabolic sequelae including hyperlipidemia, hypertension, and diabetes. Bariatric surgery has been shown to reduce the severity of the metabolic complications of obesity. METHOD: A case-controlled analysis was carried out of patients with a BMI of 35 kg/m or more from the Clinical Practice Research Datalink, a UK database of primary care clinics. Clinicopathological characteristics at baseline diagnosis were extracted. Cases of all-cause mortality were identified as a clinical endpoint. A Cox proportional hazard model was used to calculate hazard ratios (HRs) for different patient factors. A P value less than 0.050 was defined as significant. RESULTS: A total of 187,061 records were identified for analysis. Median follow-up time was 98.0 months (range: 3.0-1095.0). A total of 8655(4.6%) were identified as having died during the study period. The median time from baseline obesity diagnosis until death was 137.0 months (range: 3.0-628.7). Multivariate analysis found bariatric surgery to be associated with reduced risk of all-cause mortality (HR: 0.487; P < 0.001). The following were associated with increased risk of death: male sex (HR: 1.805; P < 0.001), BMI of 60 or greater (HR: 2.541; P < 0.001), hypertension (HR: 2.108; P < 0.001), diabetes (HR: 2.766; P < 0.001), and hyperlipidemia (HR: 1.641; P < 0.001). CONCLUSIONS: Factors such as high BMI, diabetes, hyperlipidemia, and hypertension at first diagnosis of severe obesity were each independently associated with an increased risk of death. Bariatric surgery was shown to be associated with reduced risk of all-cause mortality. Improving access to bariatric surgery and public health campaigns can improve

JOURNAL ARTICLE

Murray AC, Markar S, Mackenzie H, Baser O, Wiggins T, Askari A, Hanna G, Faiz O, Mayer E, Bicknell C, Darzi A, Kiran RPet al., 2018, An observational study of the timing of surgery, use of laparoscopy and outcomes for acute cholecystitis in the USA and UK., Surg Endosc, Vol: 32, Pages: 3055-3063

BACKGROUND: Evidence supports early laparoscopic cholecystectomy for acute cholecystitis. Differences in treatment patterns between the USA and UK, associated outcomes and resource utilization are not well understood. METHODS: In this retrospective, observational study using national administrative data, emergency patients admitted with acute cholecystitis were identified in England (Hospital Episode Statistics 1998-2012) and USA (National Inpatient Sample 1998-2011). Proportions of patients who underwent emergency cholecystectomy, utilization of laparoscopy and associated outcomes including length of stay (LOS) and complications were compared. The effect of delayed treatment on subsequent readmissions was evaluated for England. RESULTS: Patients with a diagnosis of acute cholecystitis totaled 1,191,331 in the USA vs. 288 907 in England. Emergency cholecystectomy was performed in 628,395 (52.7% USA) and 45,299 (15.7% England) over the time period. Laparoscopy was more common in the USA (82.8 vs. 37.9%; p < 0.001). Pre-treatment (1 vs. 2 days; p < 0.001) and total ( 4 vs. 7 days; p < 0.001) LOS was lower in the USA. Overall incidence of bile duct injury was higher in England than the USA (0.83 vs. 0.43%; p < 0.001), but was no different following laparoscopic surgery (0.1%). In England, 40.5% of patients without an immediate cholecystectomy were subsequently readmitted with cholecystitis. An additional 14.5% were admitted for other biliary complications, amounting to 2.7 readmissions per patient in the year following primary admission. CONCLUSION: This study highlights management practices for acute cholecystitis in the USA and England. Despite best evidence, index admission laparoscopic cholecystectomy is performed less in England, which significantly impacts subsequent healthcare utilization.

JOURNAL ARTICLE

Orihuela-Espina F, Leff DR, James DRC, Darzi AW, Yang G-Zet al., 2018, Imperial College near infrared spectroscopy neuroimaging analysis framework, NEUROPHOTONICS, Vol: 5, ISSN: 2329-423X

JOURNAL ARTICLE

Pawa N, Clift AK, Osmani H, Drymousis P, Cichocki A, Flora R, Goldin R, Patsouras D, Baird A, Malczewska A, Kinross J, Faiz O, Antoniou A, Wasan H, Kaltsas GA, Darzi A, Cwikla JB, Frilling Aet al., 2018, Surgical Management of Patients with Neuroendocrine Neoplasms of the Appendix: Appendectomy or More?, NEUROENDOCRINOLOGY, Vol: 106, Pages: 242-251, ISSN: 0028-3835

JOURNAL ARTICLE

Prime M, Attaelmanan I, Imbuldeniya A, Harris M, Darzi A, Bhatti Yet al., 2018, From Malawi to Middlesex – The case of the Arbutus Drill Cover System as an example of the cost saving potential of frugal innovations for the UK NHS, BMJ Innovations, ISSN: 2055-642X

Background:Musculoskeletal disease is one of the leading clinical and economic burdens of the UK health systemand the resultant demand for orthopaedic care is only set to increase. One commonly used and one of the most expensive hardware in orthopaedic surgery is the surgical drill and saw. Given financial constraints, the NHSneeds an economic way to address this recurring cost. We share evidence of one frugal innovation with potential for contributing to the NHS’ efficiency saving target of £22bnby 2020.Methods:Exploratory case study methodology was used to develop insights and understanding of the innovations potential for application in the NHS.Following a global search for potential frugal innovations in surgery, theArbutus Drill CoverSystem was identifiedas an innovationwith potential to deliver significant cost-savings for the NHS in the UK. Results:The Arbutus Drill Cover System is up to 94% cheaper than a standard surgical drillavailable in the UK. Clinical and laboratory tests show that performance, safety and usability is as good as current offerings in High Income Countries (HICs)and significantly better than hand drills typically used in LMICs. The innovation meets all regulatory requirements to be a medical device in the Europe and North America.Conclusions:The innovation holds promise in reducing upfront and lifespan costs for coreequipment used in orthopaedic surgerywithout loss of effectiveness or safety benchmarks. However, the innovationneedsto navigatecomplicated and decentralized procurement processesand clinicians and healthcare leaders need to overcome cognitive bias.

JOURNAL ARTICLE

Rao A, Kim D, Darzi A, Majeed A, Aylin P, Bottle Aet al., 2018, Long-term trends of use of health service among heart failure patients., Eur Heart J Qual Care Clin Outcomes

Aims: We aimed to identify subgroups in the patient population with different trajectories of long-term readmission rates. The study also aimed to assess common causes and their sequences of readmissions for each subgroup. Methods: Patients with a primary diagnosis of heart failure (HF) in the period 2008-2009 were identified using nationally representative primary care data linked to national hospital data, which contain information on 10.5 million patients. HF patients were followed up for 5 years. Group-based trajectory models and sequence analysis were applied. Results: The model categorised the HF population (n = 9466) into 5 subgroups: low-impact (66.9%); two intermediate ones (27.4%); chronic high-impact (2.3%) with steady high annual readmission rates; and short-term high-impact (3.4%) with rapid decline in readmission rates. The groups were defined by their trends of yearly number of readmissions. The all-cause 5-year mortality was highest in the short-term high-impact group (n = 185, 72.8%), followed by group 2 (intermediate users) (n = 744, 58.8%), low-impact (n = 4244, 56.9%), chronic high-impact (n = 88, 37.6%) and group 1 (intermediate users) (n = 401, 30.3%) (p < 0.01). Compared with low-impact users, high-impact users were associated with higher mortality, bereavement episodes, and more out-of-hours GP visits. The chronic high-impact users had distinct sequences of causes of emergency admissions most often consisting of chest infection, ischaemic heart disease, and cardio-pulmonary signs and/or symptoms. Conclusion: Chronic high-impact users constitute a small proportion of total patients, but they have increasingly high use of healthcare services. Short-term high-impact users represent largely end of life patients. They require prompt involvement of the palliative care team to reduce unnecessary readmissions to hospital.

JOURNAL ARTICLE

Selvendran SS, Penney NC, Aggarwal N, Darzi AW, Purkayastha Set al., 2018, Treatment of Obesity in Young People-a Systematic Review and Meta-analysis., Obes Surg

Obesity in the young is increasingly prevalent. Early, effective intervention is paramount. Treatment options are lifestyle modifications, pharmacological therapies, endoscopic treatments and bariatric surgery. However, the relative effectiveness of these treatments in young patients remains unclear. We systematically identify and meta-analyse studies evaluating weight loss treatments in young people (< 21 years) with obesity. From 16,372 identified studies, 83 were eligible for meta-analysis. Bariatric surgery resulted in high short/medium-term weight loss (pooled estimate 14.04 kg/m2). Lifestyle and pharmacological therapies impacted weight more moderately (pooled estimate 0.99 and 0.94 kg/m2 respectively). Due to its high efficacy, bariatric surgery should be considered earlier when treating obesity in young people. However, due to the invasiveness and inherent risks of bariatric surgery, all other weight loss routes should be exhausted first.

JOURNAL ARTICLE

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00171825&limit=30&person=true