Gastroenterology/Hepatology: What You May Have Missed in 2023.

This article summarizes clinically important gastroenterology developments from 2023 for internal medicine specialists. In colorectal cancer screening, a new RNA fecal screening test is on the horizon, as well as a new analysis on the benefits of using artificial intelligence in screening colonoscopy to detect more polyps. There is new evidence for management of gastrointestinal bleeding, a new drug for treatment of recurrent small-intestinal angiodysplasia, and a new endoscopic treatment method in patients with gastrointestinal tumor bleeding. The authors feature a randomized trial about amitriptyline as treatment for patients with irritable bowel syndrome by primary care providers and bring you news about new biologic agents for inflammatory bowel disease and eosinophilic esophagitis. Finally, they review 2 important articles on new terminology and management of metabolic dysfunction-associated fatty liver disease.

Financial toxicity among patients undergoing resectional surgery for inflammatory bowel disease in the United States.

AIM: Financial toxicity describes the financial burden and distress that patients experience due to medical treatment. Financial toxicity has yet to be characterized among patients with inflammatory bowel disease (IBD) undergoing surgical management of their disease. This study investigated the risk of financial toxicity associated with undergoing surgery for IBD. METHODS: This study used a retrospective analysis using the National Inpatient Sample from 2015 to 2019. Adult patients who underwent IBD-related surgery were identified using the International Classification of Diseases (10th Revision) diagnostic and procedure codes and stratified into privately insured and uninsured groups. The primary outcome was risk of financial toxicity, defined as hospital admission charges that constituted 40% or more of patient's post-subsistence income. Secondary outcomes included total hospital admission cost and predictors of financial toxicity. RESULTS: The analytical cohort consisted of 6412 privately insured and 3694 uninsured patients. Overall median hospital charges were $21 628 (interquartile range $14 758-$35 386). Risk of financial toxicity was 86.5% among uninsured patients and 0% among insured patients. Predictors of financial toxicity included emergency admission, being in the lowest residential income quartile and having ulcerative colitis (compared to Crohn's disease). Additional predictors were being of Black race or male sex. CONCLUSION: Financial toxicity is a serious consequence of IBD-related surgery among uninsured patients. Given the pervasive nature of this consequence, future steps to support uninsured patients receiving surgery, in particular emergency surgery, related to their IBD are needed to protect this group from financial risk.

Hepatitis B Virus Reactivation with Immunosuppression: A Hidden Threat?

Hepatitis B virus (HBV) reactivation in the setting of immunosuppressive therapy is an increasingly recognized and preventable cause of elevated liver enzymes and clinical hepatitis in treated patients. However, not all immunosuppressive therapies confer the same risk. The purpose of this article was to review the literature on risks of HBV reactivation associated with immunosuppressive agents and propose a management algorithm. We searched Google Scholar, PubMed, and MEDLINE for studies related to hepatitis B reactivation and various immunosuppressive agents. The risk of HBV reactivation was found to differ by agent and depending on whether a patient had chronic HBV (HBsAg+) or past HBV (HBsAg-, anti-HBc+). The highest risk of reactivation (>10%) was associated with anti-CD20 agents and hematopoietic stem cell transplants. Multiple societies recommend HBV-specific anti-viral prophylaxis for patients with positive HBsAg prior to the initiation of immunosuppressive therapy, while the guidance for HBsAg- patients is more variable. Clinicians should check HBV status prior to beginning an immune-suppressive therapy. Patients with positive HBsAg should be initiated on antiviral prophylaxis in the majority of cases, whereas HBsAg- individuals should be evaluated on a case-by-case basis. Further research is required to determine the optimum duration of therapy.

Disparities in access to minimally invasive surgery for inflammatory bowel disease and outcomes by insurance status: analysis of the 2015 to 2019 National Inpatient Sample.

INTRODUCTION: Despite being the preferred modality for treatment of colorectal cancer and diverticular disease, minimally invasive surgery (MIS) has been adopted slowly for treatment of inflammatory bowel disease (IBD) due to its technical challenges. The present study aims to assess the disparities in use of MIS for patients with IBD. METHODS: A retrospective analysis of the National Inpatient Sample (NIS) database from October 2015 to December 2019 was conducted. Patients < 65 years of age were stratified by either private insurance or Medicaid. The primary outcome was access to MIS and secondary outcomes were in-hospital mortality, complications, length of stay (LOS), and total admission cost. Univariate and multivariate regression was utilized to determine the association between insurance status and outcomes. RESULTS: The NIS sample population included 7866 patients with private insurance and 1689 with Medicaid. Medicaid patients had lower odds of receiving MIS than private insurance patients (OR 0.85, 95% CI [0.74-0.97], p = 0.017), and experienced more postoperative genitourinary complications (OR 1.36, 95% CI [1.08-1.71], p = 0.009). In addition, LOS was longer by 1.76 days (p < 0.001) and the total cost was higher by $5043 USD (p < 0.001) in the Medicaid group. Independent predictors of receiving MIS were age < 40 years old, female sex, highest income quartile, diagnosis of ulcerative colitis, elective admission, and care at teaching hospitals. CONCLUSIONS: Patients with Medicaid are less likely to receive MIS, have longer lengths of stay, and incur higher costs for the surgical management of their IBD. Further investigations into disparities in inflammatory bowel disease care for Medicaid patients are warranted.

Improvement of kidney function in patients with chronic kidney disease and severe obesity after bariatric surgery: A systematic review and meta-analysis.

The general management for chronic kidney disease (CKD) includes treating reversible causes, including obesity, which may be both a driver and comorbidity for CKD. Bariatric surgery has been shown to reduce the likelihood of CKD progression and improve kidney function in observational studies. We performed a systematic review and meta-analysis of patients with at least stage 3 CKD and obesity receiving bariatric surgery. We searched Embase, MEDLINE, CENTRAL and identified eligible studies reporting on kidney function outcomes in included patients before and after bariatric surgery with comparison to a medical intervention control if available. Risk of bias was assessed with the Newcastle-Ottawa Risk of Bias score. Nineteen studies were included for synthesis. Bariatric surgery showed improved eGFR with a mean difference (MD) of 11.64 (95%CI: 5.84 to 17.45, I2  = 66%) ml/min/1.73m2 and reduced SCr with MD of -0.24 (95%CI -0.21 to -0.39, I2  = 0%) mg/dl after bariatric surgery. There was no significant difference in the relative risk (RR) of having CKD stage 3 after bariatric surgery, with a RR of -1.13 (95%CI: -0.83 to -2.07, I2  = 13%), but there was reduced likelihood of having uACR >30 mg/g or above with a RR of -3.03 (95%CI: -1.44 to -6.40, I2  = 91%). Bariatric surgery may be associated with improved kidney function with the reduction of BMI and may be a safe treatment option for patients with CKD. Future studies with more robust reporting are required to determine the feasibility of bariatric surgery for the treatment of CKD.

Effect of Bariatric Surgery on Natriuretic Peptide Levels: A Systematic Review and Meta-Analysis.

The effect of bariatric surgery on natriuretic peptide levels in patients with obesity is unclear. The purpose of this study was to conduct a systematic review and meta-analysis to determine the effect of bariatric surgery on B-type natriuretic peptide (BNP) and aminoterminal BNP (NT-proBNP) levels. MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched to February 2020. Primary outcomes included change in NT-proBNP or BNP levels following bariatric surgery and change in weight and body mass index. Secondary outcomes included change in blood pressure, echocardiographic findings, and heart failure symptoms. MINORS tool was used to assess quality of evidence. Twelve studies with 622 patients were included. Most patients underwent Roux-en-Y gastric bypass (RYGB) (70.5%). Mean absolute reduction in body mass index was 23%. NT-proBNP levels increased significantly from baseline at 6 months (mean difference [MD] 53.67 pg/mL; 95% confidence interval [CI], 28.72-78.61; P ≤ 0.001, I2 = 99%; 8 studies) and 12 months (MD 51.16 pg/mL; 95% CI, 20.46-81.86; P = 0.001, I2 = 99%; 8 studies) postbariatric surgery. BNP levels also increased significantly at 6 months (MD 17.57 pg/mL; 95% CI, 7.62-27.51; P < 0.001, I2 = 95%; 4 studies). Systolic and diastolic blood pressure decreased significantly 12 months after surgery. Studies measuring echocardiographic findings saw improvement in left ventricle mass and the E/A ratio, but no significant change in ejection fraction. Bariatric surgery is associated with increased natriuretic peptide levels in the absence of deteriorating cardiac function, and may be associated with improved cardiac and metabolic function after the procedure.

Bariatric Surgery as a Bridge to Heart Transplantation in Morbidly Obese Patients: A Systematic Review and Meta-Analysis.

Class 2 obesity or greater [body mass index (BMI) >35 kg/m2] is a relative contraindication for heart transplant due to its associated perioperative risks and mortality. Whether bariatric surgery can act as a potential bridging procedure to heart transplantation is unknown. The aim of this systematic review and meta-analysis is to investigate the role of bariatric surgery on improving transplant candidacy in patients with end-stage heart failure (ESHF). MEDLINE, EMBASE, CENTRAL, and PubMed databases were searched up to September 2019 for studies that performed bariatric surgery on patients with severe obesity and ESHF. Outcomes of interest included incidence of patients listed for heart transplantation after bariatric surgery, proportion of patients that successfully received transplant, the change in BMI after bariatric surgery, and 30-day complications. Pooled estimates were calculated using a random-effects meta-analysis of proportions. Eleven studies with 98 patients were included. Mean preoperative BMI was 44.9 (2.1) kg/m2 and BMI after surgery was 33.2 (2.3) kg/m2 with an absolute BMI reduction of 26.1%. After bariatric surgery, 71% [95% confidence interval (CI), 55-86%] of patients with ESHF were listed for transplantation. The mean time from bariatric surgery to receiving a heart transplant was 14.9 (4.0) months. Of the listed patients, 57% (95% CI, 39-74%) successfully received heart transplant. The rate of 30-day mortality after bariatric surgery was 0%, and the 30-day major and minor complications after bariatric surgery was 28% (95% CI, 10-49%). Bariatric surgery can facilitate sustained weight loss in obese patients with ESHF, improving heart transplant candidacy and the incidence of transplantation.

Iron supplementation following bariatric surgery: A systematic review of current strategies.

Iron deficiency (ID) and iron deficiency anemia (IDA) are common following bariatric surgery; however, there are limited standardized treatment recommendations for their management. The purpose of this study was to review the current strategies for iron supplementation following bariatric surgery and assess their relative efficacy in managing ID and IDA. MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched to January 2021. Primary outcomes of interest were prevention or improvement in ID or IDA with iron supplementation. Forty-nine studies with 12,880 patients were included. Most patients underwent Roux-en-Y gastric bypass (61.9%). Iron supplementation was most commonly administered orally for prevention of ID/IDA and was effective in 52% of studies. Both IV and oral iron were given for treatment of ID/IDA. Fifty percent (3/6) of the oral and 100% (3/3) of the IV supplementation strategies were effective at treating ID. Iron supplementation strategies employed following bariatric surgery are highly variable, and many do not provide sufficient iron to prevent the development of ID and IDA, potentially due to poor patient adherence. Further high-quality prospective trials, particularly comparing intravenous and oral iron, are warranted in order to determine the ideal dosage, route, and duration of iron supplementation.

Double-balloon enteroscopy for diagnostic and therapeutic ERCP in patients with surgically altered gastrointestinal anatomy: a systematic review and meta-analysis.

BACKGROUND: Performing endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered gastrointestinal anatomy is challenging. Double-balloon enteroscopy (DBE) has been shown to be safe and efficacious for ERCP in these patients but attempts to synthesize existing data are limited. The purpose of this study was to conduct a systematic review and meta-analysis to evaluate the safety and efficacy of DBE-ERCP in surgically altered anatomy. METHODS: We searched MEDLINE, EMBASE, and CENTRAL databases through March 2020 for studies that conducted DBE-ERCP in patients with surgically altered gastrointestinal anatomy. Primary outcomes were enteroscopic, diagnostic, and procedural success rates of DBE-ERCP. Secondary outcomes were adverse events after DBE-ERCP. Random effects meta-analysis of proportions was performed when appropriate. The Newcastle-Ottawa scale was used to evaluate risk of bias. Heterogeneity was assessed using the inconsistency (I2) statistic. RESULTS: 24 studies involving 1523 patients were included. The pooled enteroscopic, diagnostic, and procedural success rates of DBE-ERCP were 90% (95% confidence interval (CI), 84-94%), 94% (95% CI 88-98%), and 93% (95% CI 88-97%). Adverse events were reported in 4% (95% CI 3-6%) of cases. Subgroup analysis of short-scope DBE-ERCP (< 200 cm) and long-scope DBE-ERCP (200 cm) did not demonstrate substantial difference in outcomes. CONCLUSION: DBE is safe and efficacious for facilitating ERCP in patients with surgically altered gastrointestinal anatomy, but RCTs or comparative studies are required to clarify its role compared to other modalities in surgically altered anatomy.

The Effect of Bariatric Surgery on Oral Antibiotic Absorption: a Systematic Review.

PURPOSE: The purpose of this study was to conduct a systematic review of the existing literature to determine the effect of bariatric surgery on various pharmacokinetic parameters of oral antibiotic absorption as well as overall patient outcomes. MATERIALS AND METHODS: MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched up to February 2020. Outcomes of interest included change in pharmacokinetic parameters of oral antibiotics administered to patients following bariatric surgery, using variables such as maximum plasma concentration (Cmax), time to reach maximum plasma concentration (Tmax), area under the concentration-time curve (AUC), clearance, and volume of distribution. MINORS and Cochrane risk of bias tools were used to assess quality of evidence. RESULTS: Ten studies with 100 patients assessing 8 oral antibiotics were included. The majority (77%) of patients underwent Roux-en-Y gastric bypass (RYGB), with fewer undergoing ventral banded gastroplasty (VBG) (14%), jejunoileostomy (6%), and jejunoileal bypass (3%). Antibiotic classes investigated included beta-lactams (5 studies), fluoroquinolones (2 studies), macrolides (2 studies), and oxazolidinones (1 study). Heterogeneity between studies precluded meaningful pooling or meta-analysis of data. Overall risk of bias was fair. CONCLUSION: Patients given oral beta-lactams and macrolides warrant close monitoring due to unpredictable absorption post-bariatric surgery, whereas oral fluoroquinolones and linezolid may not be affected. Several studies also showed decreased absorption following RYGB, as well as lower serum exposure in patients with obesity compared to non-obese controls. Clinicians should monitor patients on a case-by-case basis for signs of antibiotic failure or toxicity and reassess dosing accordingly.

Urgent Versus Standard Colonoscopy for Management of Acute Lower Gastrointestinal Bleeding: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Acute lower gastrointestinal bleeding (LGIB) is a common indication for hospitalization. However, the optimum timing of colonoscopy following patient presentation remains unclear. This systematic review and meta-analysis aims to evaluate the effect of urgent versus standard colonoscopy timing on management of acute LGIB. MATERIALS AND METHODS: Medline, EMBASE, CENTRAL, and PubMed were searched up to January 2020. Randomized controlled trials were eligible for inclusion if they compared patients with hematochezia receiving urgent (<24 h) versus standard (>24 h) colonoscopy. Nonrandomized observational studies were also included based on the same criteria for additional analysis. Pooled estimates were calculated using random effects meta-analyses and heterogeneity was quantified using the inconsistency statistic. Certainty of evidence was assessed using Grading of Recommendations, Assessment, Development and Evaluation (GRADE). RESULTS: Of 3782 potentially relevant studies, 4 randomized controlled trials involving 463 patients met inclusion criteria. Urgent colonoscopy did not differ significantly to standard timing with respect to length of stay (LOS), units of blood transfused, rate of additional intervention required, or mortality. Colonoscopy-related outcomes such as patient complications, rebleeding rates, and diagnosis of bleeding source did not differ between groups. However, meta-analysis including nonrandomized studies (9 studies, n=111,950) revealed a significantly higher rate of mortality and complications requiring surgery in the standard group and shorter LOS in the urgent group. Overall GRADE certainty of evidence was low in the majority of outcomes. CONCLUSIONS: Timing of colonoscopy in acute LGIB may not significantly affect patient outcomes. Timing should therefore be decided on a case-by-case basis.

Geographic variation in the provider of screening colonoscopy in Canada: a population-based cohort study.

BACKGROUND: Screening colonoscopy for the detection of colorectal carcinoma is provided by several specialties. Few studies have assessed geographic variation in the delivery of this care. Our objective was to investigate how geographic and socioeconomic factors affect who provides screening colonoscopy in Canada. METHODS: This was a population-based cohort of all screening colonoscopy procedures performed at publicly funded Canadian health care facilities (excluding those in Quebec) between April 2008 and March 2015. The main outcome of interest was the proportion of colonoscopy procedures performed by surgeons versus gastroenterologists at the neighbourhood level. Predictors of interest included socioeconomic and geographic variables. We used spatial analysis to evaluate significant clustering of practitioner services and multinomial logistic regression to model predictors. RESULTS: We identified 658 113 screening colonoscopy procedures performed by 1886 providers (1169 surgeons and 717 gastroenterologists) over the study period, of which 353 165 (53.7%) were performed by surgeons. A total of 24.2% of neighbourhoods were located within clusters predominantly served by gastroenterologists, and 19.5% were within surgeon clusters; the remainder were in mixed clusters. Rural neighbourhoods had a significantly increased relative risk of being within a surgeon cluster (relative risk [RR] 5.38, 95% confidence interval [CI] 3.48-8.01) compared to mixed clusters and nearly 100 times higher relative risk of being in a surgeon cluster compared to gastroenterologist clusters (RR 98.95, 95% CI 15.3-427.2). Neighbourhoods with the highest socioeconomic status were 1.74 (95% CI 1.14-2.56) times likelier to be in gastroenterologist clusters than in mixed clusters. INTERPRETATION: Surgeons provide a large proportion of colonoscopy procedures in Canada and are essential for access to care, particularly in rural regions. Most Canadians are served relatively equally by surgeons and gastroenterologists. This emphasizes the importance of both specialties to the delivery of colonoscopy care across the country.

Mastery in Bariatric Surgery: The Long-term Surgeon Learning Curve of Roux-en-Y Gastric Bypass.

OBJECTIVE: To determine the effect of cumulative volume on all-cause morbidity and operative time. BACKGROUND: Gastric bypass is an important public health procedure, but it is difficult to master with little data about how surgeon cumulative volume affects outcomes longitudinally. METHODS: This was a longitudinal study of 29 surgeons during the first 6 years of performing bariatric surgery in a high-volume, regionalized center of excellence system. Cumulative volume was determined using date and time of the procedure. Cumulative volume was analyzed in blocks of 75 cases. The main outcome of interest was all-cause morbidity during the index admission and the secondary outcome was operative time. RESULTS: Overall, 11,684 gastric bypasses were performed by 29 surgeons at 9 centers of excellence. The overall morbidity rate was 10.1% and short-term outcomes were related significantly to cumulative volume. Perioperative risk plateaued after approximately 500 cases and was lowest for surgeons who had completed more than 600 cases (odds ratio 0.53 95% confidence interval 0.26-0.96 P = 0.04) compared to the first 75 cases. Operative time also stabilized after approximately 500 cases, with an operative time 44.7 minutes faster than surgeons in their first 75 cases (95% confidence interval 37.0-52.4 min P < 0.001). CONCLUSIONS: The present study demonstrated the clear, substantial influence of surgeon cumulative volume on improved perioperative outcomes and operative time. This finding emphasizes role of the individual surgeon in perioperative outcomes and that the true learning curve needed to master a complex surgical procedure such as gastric bypass is longer than previously thought, in this case requiring approximately 500 cases to plateau.

A Longitudinal Analysis of Short-Term Costs and Outcomes in a Regionalized Center of Excellence Bariatric Care System.

BACKGROUND: Evaluating how morbidity and costs evolve for new bariatric centers is vital to understanding the expected length of time required to reach optimal outcomes and cost efficiencies. Accordingly, the objective of this study was to evaluate how morbidity and costs changed longitudinally during the first 5 years of a regionalized center of excellence system. METHODS: This was a longitudinal analysis of the first 5 years of a bariatric center of excellence system. The main outcomes of interest were all-cause morbidity and cost for the index admission. Predictors of interest included patient demographics, comorbidities, annual hospital and surgeon volume, fellowship teaching center status, and year of procedure. Hierarchical regression models were used to determine predictors of morbidity and costs. RESULTS: Procedures done in 2012 (OR 0.65, 95%CI 0.52-0.79; p < 0.001), 2013 (OR 0.63, 95%CI 0.51-0.78; p < 0.001), and 2014 (OR 0.53, 95%CI 0.43-0.65; p < 0.001) all conferred a significantly lower odds of morbidity when compared to the initial 2009/2010 years. Surgeon volume was associated with a decreased odds of morbidity as for each increase in 25 bariatric cases per year the odds of all-cause morbidity was 0.94 lower (95%CI 0.88-1.00; p = 0.04). There was no significant variation at the hospital or surgeon level in perioperative outcomes. CONCLUSION: This study determined that volume was important even for high resource, fellowship-trained surgeons. It also found a decrease in morbidity over time for new centers. Lastly, there was little variation in outcomes across hospitals and surgeons suggesting that strict accreditation standards can help to ensure high quality across hospital sites.

The effect of health system factors on outcomes and costs after bariatric surgery in a universal healthcare system: a national cohort study of bariatric surgery in Canada.

INTRODUCTION: Previous data demonstrate that patients who receive bariatric surgery at a Center of Excellence are different than those who receive care at non-accredited centers. Canada provides a unique opportunity to naturally exclude confounders such as insurance status, hospital ownership, and lack of access on comparisons between hospitals and surgeons in bariatric surgery outcomes. The objective of this study was to determine the effect of hospital accreditation and other health system factors on all-cause morbidity after bariatric surgery in Canada. METHODS: This was a population-based study of all patients aged ≥18 who received a bariatric procedure in Canada (excluding Quebec) from April 2008 until March 2015. The main outcomes for this study were all-cause morbidity and costs during the index admission. All-cause morbidity included any documented complication which extended length of stay by 24 h or required reoperation. Risk-adjusted hierarchical regression models were used to determine predictors of morbidity and cost. RESULTS: Overall, 18,398 patients were identified and the all-cause morbidity rate was 10.1%. Surgeon volume and teaching hospitals were both found to significantly decrease the odds of all-cause morbidity. Specifically, for each increase in 25 bariatric cases per year, the odds of all-cause morbidity was 0.94 times lower (95% CI 0.87-1.00, p = 0.03). Teaching hospitals conferred a 0.75 lower odds of all-cause morbidity (95% CI 0.58-0.95, p < 0.001). Importantly, formal accreditation was not associated with a decrease in all-cause morbidity within a universal healthcare system. No health system factors were associated with significant cost differences. CONCLUSION: This national cohort study found that surgeon volume and teaching hospitals predicted lower all-cause morbidity after surgery while hospital accreditation was not a significant factor.

The effect of an online referral system on referrals to bariatric surgery.

BACKGROUND: The Ontario Bariatric Network implemented an online referral system to completely replace a fax-based system in 2015. Strategies such as electronic information transfer have been suggested to improve the bariatric referral process but few studies exist demonstrating their efficacy. Therefore, the purpose of this study was to determine the impact on referral rates to bariatric surgery after converting to an online referral system from a fax-based system. METHODS: All referrals from 2011 to 2015 were included in the study. The main outcomes included the total number of referrals and whether a practitioner increased referrals after the implementation of the online referral system. A hierarchical logistic regression model was used for the final analysis. Predictors of interest included physician and neighbourhood level factors RESULTS: Referrals more than doubled overall and increased significantly across all health regions. Compared to practitioners in their first five years, all other experience groups were approximately 50% less likely to increase referrals. Compared to those within 50 km of a bariatric facility, practitioners 50-99 km (OR 0.76 95% CI 0.58-0.98 p = 0.04) and 100-199 km (OR 0.73 95% CI 0.55-0.96 p = 0.03) away were both significantly less likely to increase referrals. CONCLUSION: This study found that referrals increased significantly after implementing an online referral system. Furthermore, physicians in their first five years of practice as well as those practicing closer to bariatric centers were more likely to increase referrals. Our findings demonstrate that an online referral system may aid in increasing referrals to bariatric surgery.