Browsing by Author "Forbes, Nauzer"

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    Development and internal validation of a risk prediction model for high-risk adenomas among average risk colorectal cancer screening participants
    (2020-09-03) Sutherland, Robert Liam; Brenner, Darren R.; Hilsden, R. J.; Forbes, Nauzer
    Background: High-risk adenomas (HRAs) are precursors to colorectal cancer (CRC), and removing them during colonoscopy can halt progression to CRC. The aim of this study was to develop a risk prediction model for HRAs detected at screening colonoscopy based on readily available patient information. Subsequently, we aimed to understand if biomarkers of glucose metabolism were associated with HRAs, with hopes incorporating them into a baseline risk prediction model to enhance its clinical utility. Methods: The cohort consisted of 3,035 individuals aged 50 to 74 years with no prior history of cancer who underwent a primary screening colonoscopy at a centralized colon cancer screening centre between 2008 and 2016. A multivariable logistic regression model was created using CRC risk factors identified from prior research. Model covariates were collected from a baseline questionnaire and included patient demographics (age and sex), lifestyle parameters (body mass index, alcohol, smoking, and vitamin D supplement use) and medical history (family history of CRC and diabetes). Model calibration was assessed using the c-statistic. Glucose, insulin, glycated hemoglobin A1c, and c-peptide were all measured were assessed using a case control study design from from a subset of the CCSC biorepository.conditional logistic regression was used to understand their associations with HRAs. Results: Mean participant age was 58.8 years, and 54.7% were male. A total of 249 participants with HRAs were identified (8.2%). An optimism adjusted c-statistic of 0.67 was calculated, and a specificity and negative predictive value of 97.0% and 92.4% for the detection of HRAs respectively, were achieved using 20% predicted probability as a high-risk threshold. However, a sensitivity of only 10.8% was achieved. Our model has moderate predictive ability, with strengths in being able to rule those with an absence of HRAs on screening colonoscopy. Finally, after adjustment, no meaningful associations were found between these four biomarkers of glucose metabolism and HRAs. Conclusion: Although these glucose metabolism biomarkers were not found to be associated with HRAs, the production of a simple risk prediction model can still provide benefit to the current screening programs in Alberta. Maximizing screening efficiency through improved risk prediction can enhance resource allocation. Ultimately, this model has the potential to improve patient care by reducing unnecessary colonoscopies, limiting this invasive procedure to those most likely to have significant findings.
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    ELEMENT TRIAL: study protocol for a randomized controlled trial on endoscopic ultrasound-guided biliary drainage of first intent with a lumen-apposing metal stent vs. endoscopic retrograde cholangio-pancreatography in the management of malignant distal biliary obstruction
    (2019-12-09) Chen, Yen-I; Callichurn, Kashi; Chatterjee, Avijit; Desilets, Etienne; Fergal, Donnellan; Forbes, Nauzer; Gan, Ian; Kenshil, Sana; Khashab, Mouen A; Kunda, Rastislav; Lam, Eric; May, Gary; Mohamed, Rachid; Mosko, Jeff; Paquin, Sarto C; Sahai, Anand; Sandha, Gurpal; Teshima, Christopher; Barkun, Alan; Barkun, Jeffrey; Bessissow, Ali; Candido, Kristina; Martel, Myriam; Miller, Corey; Waschke, Kevin; Zogopoulos, George; Wong, Clarence
    Abstract Background & aims Endoscopic ultrasound guided-biliary drainage (EUS-BD) is a promising alternative to endoscopic retrograde cholangiopancreatography (ERCP); however, its growth has been limited by a lack of multicenter randomized controlled trials (RCT) and dedicated devices. A dedicated EUS-BD lumen- apposing metal stent (LAMS) has recently been developed with the potential to greatly facilitate the technique and safety of the procedure. We aim to compare a first intent approach with EUS-guided choledochoduodenostomy with a dedicated biliary LAMS vs. standard ERCP in the management of malignant distal biliary obstruction. Methods The ELEMENT trial is a multicenter single-blinded RCT involving 130 patients in nine Canadian centers. Patients with unresectable, locally advanced, or borderline resectable malignant distal biliary obstruction meeting the inclusion and exclusion criteria will be randomized to EUS-choledochoduodenostomy using a LAMS or ERCP with traditional metal stent insertion in a 1:1 proportion in blocks of four. Patients with hilar obstruction, resectable cancer, or benign disease are excluded. The primary endpoint is the rate of stent dysfunction needing re-intervention. Secondary outcomes include technical and clinical success, interruptions in chemotherapy, rate of surgical resection, time to stent dysfunction, and adverse events. Discussion The ELEMENT trial is designed to assess whether EUS-guided choledochoduodenostomy using a dedicated LAMS is superior to conventional ERCP as a first-line endoscopic drainage approach in malignant distal biliary obstruction, which is an important and timely question that has not been addressed using an RCT study design. Trial registration Registry name: ClinicalTrials.gov. Registration number: NCT03870386. Date of registration: 03/12/2019.
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    Epidemiology and outcomes of choledocholithiasis and cholangitis in the United States: trends and urban-rural variations
    (2023-07-27) Li, Suqing; Guizzetti, Leonardo; Ma, Christopher; Shaheen, Abdel A.; Dixon, Elijah; Ball, Chad; Wani, Sachin; Forbes, Nauzer
    Abstract Background Gallstone disease poses a significant health burden in the United States. Choledocholithiasis and cholangitis are common complications of gallstone disease for which data on current epidemiological trends are lacking. We aimed to evaluate temporal changes in hospitalization, management, and outcomes for patients with choledocholithiasis and cholangitis. Methods The National Inpatient Sample was used to identify discharges for choledocholithiasis and cholangitis between 2005 and 2014. Temporal trends were evaluated via annual percent changes (APCs). Joinpoint regression was used to assess inflection points. Multivariable regression models were used to evaluate associations of interest. Results From 189,362 unweighted discharges for choledocholithiasis and/or cholangitis, there was an increase in discharges for choledocholithiasis (APC 2.3%, 95% confidence intervals, CI, 1.9–2.7%) and cholangitis (APC 1.5%, 95% CI 0.7–2.2%). Procedural interventions were more likely at urban hospitals for choledocholithiasis (adjusted odds ratio, aOR, 2.94, 95% CI 2.72 to 3.17) and cholangitis (aOR 2.97, 95% CI 2.50 to 3.54). In-hospital mortality significantly decreased annually for choledocholithiasis (aOR 0.90, 95% CI 0.88 to 0.93) and cholangitis (aOR 0.93, 95% CI 0.89 to 0.97). In-hospital mortality between rural and urban centers was comparable for choledocholithiasis (aOR 1.16, 95% CI 0.89 to 1.52) and cholangitis (aOR 1.12, 95% CI 0.72 to 1.72). Conclusions Hospitalizations for choledocholithiasis and cholangitis have increased between 2005 and 2014, reflecting a growing burden of gallstone disease. Hospital mortality between urban and rural centers is similar, however urban centers have a higher rate of procedural interventions suggesting limitations to accessing procedural interventions at rural centers.
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    Incidence and Risk Factors Associated with Endoscopic Retrograde Cholangiopancreatography-Related Bleeding
    (2022-06) Bishay, Kirles; Forbes, Nauzer; Heitman, Steven; Hilsden, Robert; Bridges, Ron
    Endoscopic retrograde cholangiopancreatography (ERCP) is the cornerstone of therapy for an array of pancreaticobiliary disorders. While highly effective, ERCP-related bleeding is a possible adverse event with an estimated incidence of 2% which can lead to substantial morbidity and mortality. This thesis reports the results of two studies performed with the aim of evaluating the incidence of and risk factors associated with the development of ERCP-related bleeding. Our meta-analysis of observational and randomized trials showed that while the contemporary incidence of bleeding is in keeping with historical estimates, bleeding risk varies considerably within several important patient- and procedure-related subgroups. We then demonstrated via a multicenter prospective cohort study the risk factors associated with both intraprocedural and clinically significant delayed ERCP-related bleeding. We demonstrated that patient sex, kidney disease, papilla morphology, antithrombotic use and procedural techniques contribute to bleeding risk after adjusting for important covariates. Together, these findings demonstrate that bleeding risk in ERCP varies substantially depending on several factors. Clinicians performing ERCP can use our findings to accurately assess bleeding risk permitting tailored risk mitigation management amongst individuals at high risk and to communicate accurate bleeding risk estimates to patients for conferral of informed consent.
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    Infection control in ERCP using a duodenoscope with a disposable cap (ICECAP): rationale for and design of a randomized controlled trial
    (2020-03-12) Forbes, Nauzer; Elmunzer, B. J; Allain, Thibault; Chau, Millie; Koury, Hannah F; Bass, Sydney; Belletrutti, Paul J; Cole, Martin J; Gonzalez-Moreno, Emmanuel; Kayal, Ahmed; Kumar, Puja; Mohamed, Rachid; Turbide, Christian; Buret, Andre G; Heitman, Steven J
    Abstract Background Endoscopic retrograde cholangio-pancreatography (ERCP) is commonly performed in the management of pancreatic and biliary disease. Duodenoscopes are specialized endoscopes used to perform ERCP, and inherent to their design, a high rate of persistent bacterial contamination exists even after automated reprocessing and disinfection. Consequently, in recent years, ERCP has been associated with infection transmission, leading to several fatal patient outbreaks. Due to increasing fears over widespread future duodenoscope-related outbreaks, regulatory bodies have called for alterations in the design of duodenoscopes. A duodenoscope has recently been developed that employs a disposable cap. This novel design theoretically eliminates the mechanism behind persistent bacterial contamination and infection transmission. However, there are no data demonstrating persistent bacterial contamination rates, technical success rates, or clinical outcomes associated with these duodenoscopes. Methods A parallel arm randomized controlled trial will be performed for which 520 patients will be recruited. The study population will consist of consecutive patients undergoing ERCP procedures for any indication at a high-volume tertiary care centre in Calgary, Alberta, Canada. Patients will be randomized to an intervention group, that will undergo ERCP with a novel duodenoscope with disposable cap, or to a control group who will undergo ERCP with a traditional duodenoscope. Co-primary outcomes will include persistent bacterial contamination rates (post automated reprocessing) and ERCP technical success rates. Secondary outcomes include clinical success rates, overall and specific early and late adverse event rates, 30-day mortality and healthcare utilization rates, procedure and reprocessing times, and ease of device use. Discussion The ICECAP trial will answer important questions regarding the use of a novel duodenoscope with disposable cap. Specifically, persistent bacterial contamination, technical performance, and relevant clinical outcomes will be assessed. Given the mortality and morbidity burden associated with ERCP-related infectious outbreaks, the results of this study have the capacity to be impactful at an international level. Trial registration This trial was registered on clinicaltrials.gov (NCT04040504) on July 31, 2019.
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    Outcomes of Endoscopic Retrograde Cholangiopancreatography in Patients with Underlying Mental Health Disorders
    (2024-10-15) Tepox Padron, Alejandra; Forbes, Nauzer; El-Gabalawy, Renée; Hilsden, Robert Jay
    Depression and anxiety are significant contributors to the global health burden. In Canada, the lifetime prevalences of depression and anxiety among adults are around 11% and 9%, respectively. These mental health disorders (MHDs) increase post-operative adverse events (AEs), worsen outcomes, and negatively impact healthcare correlates. In gastrointestinal endoscopy settings, pre-procedural anxiety reduces patient satisfaction and increases pain sensitivity and requirements for sedatives. Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for managing certain pancreaticobiliary conditions. However, it is technically challenging and has the highest rates of AEs and unplanned hospital encounters (UHEs) among endoscopic procedures. There is a knowledge gap regarding the impact of MHDs on ERCP-related outcomes and patient-reported tolerability with conscious sedation. This thesis presents results from two studies seeking to examine the associations between pre-existing MHDs in adult patients undergoing ERCP and: 1) UHEs within 30 days of the procedure, including unplanned emergency department visits and/or admissions for somatic symptoms only without a clear explanatory diagnosis or AE (Study 1), 2) AEs within 30 days of the procedure (Study 1), and 3) patient-reported peri- and post-procedural tolerability (Study 2). Secondary analyses of multi-centre data were conducted using logistic regression while accounting for pertinent covariates. Study 1 found no significant associations between pre-existing MHDs and UHEs or AEs in 6,648 patients undergoing ERCP within 30 days, including visits or admissions for somatic symptoms alone. Conversely, Study 2 demonstrated a significant association between MHDs and poorer patient-reported tolerability of ERCP under conscious sedation. Among 3,714 patients, significantly more participants with MHDs reported increased intra-procedural awareness and discomfort, along with greater post-procedural abdominal pain, nausea, and distension. Using these data, clinicians performing ERCP can provide accurate information regarding MHDs and ERCP-related outcomes. Additionally, increased awareness of the reduced tolerability and worse patient-reported experience measures of ERCP under conscious sedation in patients with depression and/or anxiety can help endoscopists decrease potential patient morbidity and enhance satisfaction. Further study is needed to determine potential associations between more granular MHD-related exposures and post-ERCP outcomes.
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    Practice Patterns, Predictors of Use and Clinical Efficacy of Endoscopic Clips for Prevention of Delayed Post-polypectomy Bleeding
    (2017-12-12) Forbes, Nauzer; Heitman, Steven; Hilsden, Robert; Kaplan, Gilaad; James, Matthew
    Colonoscopy reduces colorectal cancer through the removal of pre-cancerous polyps, which exposes patients to potential adverse events. Endoscopic clips are used by practitioners to prevent delayed post-polypectomy bleeding. This thesis reports the results of two studies performed with the aim of evaluating the practice patterns and clinical efficacy of prophylactic clipping during polypectomy. A meta-analysis of randomized trials showed that prophylactic clipping is not efficacious in preventing delayed bleeding during routine polypectomy, especially among polyps < 10 mm. A large retrospective cohort study then described clinical parameters associated with clip usage. We demonstrated that use of clips increased over time in a high-volume outpatient endoscopy unit. Furthermore, a high degree of variability in clipping patterns existed between endoscopists, including among polyps < 10 mm, where no efficacy exists. Taken together, these results reveal an urgent need for effective knowledge translation to eliminate this ineffective and costly practice during routine polypectomy.
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    Predicting the Risk of Post Endoscopic Retrograde Cholangiopancreatography Pancreatitis
    (2023-07) Meng, Zhao Wu; Forbes, Nauzer; Brenner, Darren; Heitman, Steve
    Background Post- endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) can lead to significant morbidity and even mortality. The aim of this study was to develop a PEP prediction model using easily accessible patient- and procedure-related variables. Methods Using a multi center prospective ERCP registry, we conducted logistic regression using stepwise selection on several patient- and procedure-related variables that were determined a priori. Variables were included or excluded based on an initial alpha cut-off of 0.2. The final model was based on a combination of Bayesian information criterion (BIC) and Akaike's information criterion (AIC) performance, as well as on the inclusion of variables deemed to be of clinical relevance, while maintaining face validity. All available data was used for model development, with subsequent internal validation performed on bootstrapped data using 10-fold cross validation. Results From September 1, 2019 to January 16, 2022, 3021 ERCP procedures were enrolled and included in our study. There were 151 (5.0%) cases of PEP. Variables included in the final model were patient sex, patient age, pancreatic duct cannulation, native papilla status, presence of precut sphincterotomy, cannulation time, presence of biliary stricture, and pancreatic duct stenting. The final model had an AIC, BIC, and receiver operating characteristic (ROC) curve of 822.28, 886.77, and 0.79, respectively. Bootstrapped data using 800 replicates revealed a C-statistic of 0.78 and expected to observed (E:O) ratio of 1.003. Conclusion This study successfully established and internally validated a promising PEP predictive model using easily obtainable variables that are known at baseline or observed during the ERCP procedure. The model achieved an area under the curve of 0.79. External validation is required prior to clinical use.