Standardised training for endoscopic mucosal resection of large non-pedunculated colorectal polyps to reduce recurrence (*STAR-LNPCP study): a multicentre cluster randomised trial

OBJECTIVE

Endoscopic mucosal resection (EMR) is the preferred treatment for non-invasive large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) but is associated with an early recurrence rate of up to 30%. We evaluated whether standardised EMR training could reduce recurrence rates in Dutch community hospitals.

DESIGN

In this multicentre cluster randomised trial, 59 endoscopists from 30 hospitals were randomly assigned to the intervention group (e-learning and 2-day training including hands-on session) or control group. From April 2019 to August 2021, all consecutive EMR-treated LNPCPs were included. Primary endpoint was recurrence rate after 6 months.

RESULTS

A total of 1412 LNPCPs were included; 699 in the intervention group and 713 in the control group (median size 30 mm vs 30 mm, 45% vs 52% size, morphology, site and access (SMSA) score IV, 64% vs 64% proximal location). Recurrence rates were lower in the intervention group compared with controls (13% vs 25%, OR 0.43; 95% CI 0.23 to 0.78; p=0.005) with similar complication rates (8% vs 9%, OR 0.93; 95% CI 0.64 to 1.36; p=0.720). Recurrences were more often unifocal in the intervention group (92% vs 76%; p=0.006). In sensitivity analysis, the benefit of the intervention on recurrence rate was only observed in the 20-40 mm LNPCPs (5% vs 20% in 20-29 mm, p=0.001; 10% vs 21% in 30-39 mm, p=0.013) but less evident in ≥40 mm LNPCPs (24% vs 31%; p=0.151). In a post hoc analysis, the training effect was maintained in the study group, while in the control group the recurrence rate remained high.

CONCLUSION

A compact standardised EMR training for LNPCPs significantly reduced recurrences in community hospitals. This strongly argues for a national dedicated training programme for endoscopists performing EMR of ≥20 mm LNPCPs. Interestingly, in sensitivity analysis, this benefit was limited for LNPCPs ≥40 mm.

TRIAL REGISTRATION NUMBER

NTR7477.

Artificial intelligence for characterization of diminutive colorectal polyps: A feasibility study comparing two computer-aided diagnosis systems

BACKGROUND

Artificial intelligence (AI) has potential in the optical diagnosis of colorectal polyps.

AIM

To evaluate the feasibility of the real-time use of the computer-aided diagnosis system (CADx) AI for ColoRectal Polyps (AI4CRP) for the optical diagnosis of diminutive colorectal polyps and to compare the performance with CAD EYE^TM (Fujifilm, Tokyo, Japan). CADx influence on the optical diagnosis of an expert endoscopist was also investigated.

METHODS

AI4CRP was developed in-house and CAD EYE was proprietary software provided by Fujifilm. Both CADx-systems exploit convolutional neural networks. Colorectal polyps were characterized as benign or premalignant and histopathology was used as gold standard. AI4CRP provided an objective assessment of its characterization by presenting a calibrated confidence characterization value (range 0.0-1.0). A predefined cut-off value of 0.6 was set with values < 0.6 indicating benign and values ≥ 0.6 indicating premalignant colorectal polyps. Low confidence characterizations were defined as values 40% around the cut-off value of 0.6 (< 0.36 and > 0.76). Self-critical AI4CRP’s diagnostic performances excluded low confidence characterizations.

RESULTS

AI4CRP use was feasible and performed on 30 patients with 51 colorectal polyps. Self-critical AI4CRP, excluding 14 low confidence characterizations [27.5% (14/51)], had a diagnostic accuracy of 89.2%, sensitivity of 89.7%, and specificity of 87.5%, which was higher compared to AI4CRP. CAD EYE had a 83.7% diagnostic accuracy, 74.2% sensitivity, and 100.0% specificity. Diagnostic performances of the endoscopist alone (before AI) increased non-significantly after reviewing the CADx characterizations of both AI4CRP and CAD EYE (AI-assisted endoscopist). Diagnostic performances of the AI-assisted endoscopist were higher compared to both CADx-systems, except for specificity for which CAD EYE performed best.

CONCLUSION

Real-time use of AI4CRP was feasible. Objective confidence values provided by a CADx is novel and self-critical AI4CRP showed higher diagnostic performances compared to AI4CRP.

Spatio-temporal dynamics of the human small intestinal microbiome and its response to a synbiotic

Although fecal microbiota composition is considered to preserve relevant and representative information for distal colonic content, it is evident that it does not represent microbial communities inhabiting the small intestine. Nevertheless, studies investigating the human small intestinal microbiome and its response to dietary intervention are still scarce. The current study investigated the spatio-temporal dynamics of the small intestinal microbiome within a day and over 20 days, as well as its responses to a 14-day synbiotic or placebo control supplementation in 20 healthy subjects. Microbial composition and metabolome of luminal content of duodenum, jejunum, proximal ileum and feces differed significantly from each other. Additionally, differences in microbiota composition along the small intestine were most pronounced in the morning after overnight fasting, whereas differences in composition were not always measurable around noon or in the afternoon. Although overall small intestinal microbiota composition did not change significantly within 1 day and during 20 days, remarkable, individual-specific temporal dynamics were observed in individual subjects. In response to the synbiotic supplementation, only the microbial diversity in jejunum changed significantly. Increased metabolic activity of probiotic strains during intestinal passage, as assessed by metatranscriptome analysis, was not observed. Nevertheless, synbiotic supplementation led to a short-term spike in the relative abundance of genera included in the product in the small intestine approximately 2 hours post-ingestion. Collectively, small intestinal microbiota are highly dynamic. Ingested probiotic bacteria could lead to a transient spike in the relative abundance of corresponding genera and ASVs, suggesting their passage through the entire gastrointestinal tract. This study was registered to http://www.clinicaltrials.gov, NCT02018900.

Hyperferritinemia and liver iron content determined with MRI: Reintroduction of the liver iron index

BACKGROUND

Hyperferritinemia is found in around 12 % of the general population. Analyzing the cause can be difficult. In case of doubt about the presence of major iron overload most guidelines advice to perform a MRI as a reliable non-invasive marker to measure liver iron concentration (LIC). In general, a LIC of ≥ 36 µmol/g dw is considered the be elevated however in hyperferritinemia associated with, for example, obesity or alcohol (over)consumption the LIC can be ≥ 36 µmol/g dw in abscence of major iron overload. So, unfortunately a clear cut-off value to differentiate iron overload from normal iron content is lacking. Previously the liver iron index (LII) (LIC measured in liver biopsy (LIC-b)/age (years)), was introduced to differentiate between patients with major (LII ≥ 2) and minor or no iron overload (LII < 2). Based on the good correlation between the LIC-b and LIC determined with MRI (LIC-MRI), our goal was to investigate whether a LII_MRI ≥ 2 is a good indicator of major iron overload, reflected by a significantly higher amount of iron needed to be mobilized to reach iron depletion.

METHODS

We compared the amount of mobilized iron to reach depletion and inflammation-related characteristics in two groups: LII-MRI ≥ 2 versus LII-MRI <2 in 92 hyperferritinemia patients who underwent HFE genotyping and MRI-LIC determination.

RESULTS

Significantly more iron needed to be mobilized to reach iron depletion in the LII ≥ 2 group (mean 4741, SD ± 4135 mg) versus the LII-MRI <2 group (mean 1340, SD ± 533 mg), P < 0.001. Furthermore, hyperferritinemia in LII-MRI < 2 patients was more often related to components of the metabolic syndrome while hyperferritinemia in LII-MRI ≥ 2 patients was more often related to HFE mutations. ROC curve analysis showed good performance of LII =2 as cut-off value. However the calculations showed that the optimal cut-off for the LII = 3.4.

CONCLUSION

The LII-MRI with a cut-off value of 2 is an effective method to differentiate major from minor iron overload in patients with hyperferritinemia. But the LII-MRI = 3.4 seems a more promising diagnostic test for major iron overload.

Satisfaction With Life in IBS Is Associated With Psychological Burden Rather than Gastrointestinal Symptom Severity

INTRODUCTION

Irritable bowel syndrome (IBS) has a major impact on emotional, social, and professional life. This study aimed to evaluate general life satisfaction, a subjective measure of well-being, in IBS patients, and to determine which factors are associated with higher life satisfaction.

METHODS

IBS patients (n = 195, mean age 51.4 ± 16.5 years, 73.8% female) recruited from primary and secondary/tertiary care completed questionnaires regarding gastrointestinal symptoms, quality of life, psychological factors, and life satisfaction (Satisfaction With Life Scale, 5 items, range 5-35). A finite mixture model analysis was performed to identify latent classes. Multivariable linear regression was used to identify variables associated with life satisfaction.

RESULTS

Overall, 71.3% of the patients were satisfied about their life (Satisfaction With Life Scale-score ≥21). Three latent subgroups could be identified with significantly higher life satisfaction in the subgroup with higher mental quality of life, fewer anxiety and depressive symptoms, lower gastrointestinal specific anxiety, and lower gastrointestinal symptom severity, compared with the other 2 groups. Multivariable linear regression showed that higher physical quality of life (B0.168, P < 0.001) and higher mental quality of life (B0.199, P < 0.001) were associated with higher life satisfaction. Using multivariable regression, no significant association was found between gastrointestinal symptom severity and life satisfaction.

DISCUSSION

Higher physical and mental quality of life, but not gastrointestinal symptom severity, were independently associated with higher general life satisfaction in IBS. These findings reinforce the clinical need in IBS treatment to focus on the full extent of the disorder and not merely on gastrointestinal symptom improvement. ClinicalTrials.gov Identifier: NCT00775060.

Dumping Syndrome: Pragmatic Treatment Options and Experimental Approaches for Improving Clinical Outcomes

Dumping syndrome is a common complication after esophageal, gastric and bariatric surgery and has a significant negative impact on the quality of life of patients. This narrative review describes the clinical syndrome, pathophysiology, diagnosis and reports on standard and pragmatic therapeutical treatment options in order to improve the clinical outcome of patients with dumping syndrome. Dumping syndrome consists of early and late dumping symptoms and can be diagnosed using clinical parameters with the help of the Sigstad's score, questionnaires or by provocative testing. The prevalence of dumping syndrome varies depending on the employed definition of dumping syndrome. Overall, dumping syndrome is more frequent nowadays due to increasing numbers of upper gastrointestinal and bariatric surgeries being performed. First treatment step includes dietary adjustment and dietary supplements, which are often sufficient to manage symptoms for the majority of patients. Next step of therapy includes acarbose, which is effective for late dumping symptoms, but the use is limited due to side effects. Somatostatin analogues are indicated after these two steps have failed. Somatostatin analogues are very effective for controlling early and late dumping, also in the long term. Glucagon like peptide-1 receptor agonists, endoscopic and surgical (re)interventions are reported as treatment options for refractory dumping syndrome; however, their use is not recommended in clinical practice due to the limited evidence on and uncertainty of outcomes. These alternatives should be considered only as last resort options in patients with otherwise refractory and invalidating dumping syndrome.

[Irritable bowel syndrome]

Irritable bowel syndrome (IBS) is a prevalent disorder of the gut-brain interaction, of which the multifactorial pathophysiology is still incompletely understood. IBS is a symptom-based diagnosis based on the Rome IV criteria, and additional diagnostics are only indicated when history or physical examination point towards the presence of other (organic) disorders. Diagnosis and treatment should take place in primary care. However, management of IBS can be challenging due to the heterogenous clinical presentation. Furthermore, a variety of treatment options are available, yet only effective in subgroups of patients. Early positive diagnosis, patient education, and shared-decision making are of utmost importance in order to limit individual disease burden and the socioeconomic impact of IBS. In this review we discuss diagnosis, indications for additional investigations or referral to secondary care, and treatment of IBS, based on both the recently updated Dutch guideline and general practice standard on IBS.

Impact of Sleeve Gastrectomy on Fecal Microbiota in Individuals with Morbid Obesity

BACKGROUND

The intestinal microbiota plays an important role in the etiology of obesity. Sleeve gastrectomy (SG) is a frequently performed and effective therapy for morbid obesity.

OBJECTIVE

To investigate the effect of sleeve gastrectomy on the fecal microbiota of individuals with morbid obesity and to examine whether shifts in microbiota composition are associated with markers of inflammation and intestinal barrier function.

METHODS

Fecal and blood samples of healthy individuals (n = 27) and morbidly obese individuals pre-SG (n = 24), and at 2 months (n = 13) and 6 months post-SG (n = 9) were collected. The 16SrRNA gene was sequenced to assess microbiota composition. Fecal calprotectin, plasma inflammatory markers and intestinal permeability markers (multi-sugar test) were determined.

RESULTS

Fecal microbiota composition between morbidly obese and lean individuals was significantly different. The fecal microbiota composition changed significantly 2 and 6 months post-SG (p = 0.008) compared to pre-SG but not towards a more lean profile. The post-SG microbiota profile was characterized by an increase in facultative anaerobic bacteria, characteristic for the upper gastrointestinal tract. No correlations were found between inflammatory markers, intestinal permeability and microbial profile changes.

CONCLUSIONS

Fecal microbiota composition in morbidly obese individuals changed significantly following SG. This change might be explained by functional changes induced by the SG procedure.

The Socioeconomic Impact of Irritable Bowel Syndrome: An Analysis of Direct and Indirect Health Care Costs

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is associated with substantial costs to society. Extensive data on direct costs (health care consumption) and indirect costs (health-related productivity loss) are lacking. Hence, we examined the socioeconomic costs of IBS and assessed which patient characteristics are associated with higher costs.

METHODS

Cross-sectional data from 3 Rome-defined Dutch IBS patient cohorts (n = 419) were collected. Bootstrapped mean direct and indirect costs were evaluated per patient with IBS using validated questionnaires (ie, medical cost questionnaire and productivity cost questionnaire, respectively). Multivariable regression analyses were performed to identify variables associated with higher costs.

RESULTS

Quarterly mean total costs per patient were €2.156 (95% confidence interval (CI), €1793-€2541 [$2444]), consisting of €802 (95% CI, €625-€1010 [$909]) direct costs and €1.354 (95% CI, €1072-€1670 [$1535]) indirect costs. Direct costs consisted primarily of health care professional consultations, with costs related to gastrointestinal clinic visits accounting for 6% and costs related to mental health care visits for 20%. Higher direct costs were significantly associated with older age (P = .007), unemployment (P = .001), IBS subtypes other than constipation (P = .033), lower disease-specific quality of life (P = .027), and more severe depressive symptoms (P = .001). Indirect costs consisted of absenteeism (45%), presenteeism (42%), and productivity loss related to unpaid labor (13%) and were significantly associated with the male sex (P = .014) and more severe depressive symptoms (P = .047).

CONCLUSIONS

Productivity loss is the main contributor to the socioeconomic burden of IBS. Direct costs were not predominantly related to gastrointestinal care, but rather to mental health care. Awareness of the nature of costs and contributing patient factors should lead to significant socioeconomic benefits for society.

Systematic review on sleeve gastrectomy or Roux-en-Y gastric bypass surgery for refractory gastroparesis

Management of refractory gastroparesis is challenging after diet, prokinetics, and long-term nutritional support have failed. In this review, the efficacy and safety of surgical interventions (sleeve gastrectomy and Roux-en-Y gastric bypass surgery) are evaluated systematically in patients with refractory gastroparesis. The PubMed, Embase, and Scopus databases were searched to identify relevant studies published up to June 2021. Outcome of interest was symptom improvement and gastric emptying. Nineteen studies with 222 refractory gastroparesis patients (147 Roux-en-Y gastric bypass, 39 sleeve gastrectomy, and 36 subtotal gastrectomy) were included. All studies reported symptom improvement postoperatively, particularly vomiting and nausea. Gastric emptying improved postoperatively in 45% up to 67% for sleeve gastrectomy and 87% for Roux-en-Y gastric bypass. The findings of our systematic review suggest that sleeve gastrectomy and Roux-en-Y gastric bypass surgery improve symptoms and gastric emptying in patients with refractory gastroparesis. Surgery may be effective as treatment for a small group of patients when all other therapies have failed.

Colonic permeability is increased in non-cirrhotic patients with nonalcoholic fatty liver disease

BACKGROUND AND AIM

Intestinal permeability (IP) plays an important role in the pathophysiology of nonalcoholic fatty liver disease (NAFLD). We assessed site-specific (gastroduodenum, small intestine, colon and whole gut) IP in NAFLD patients and healthy controls (HC) and its association with the degree of hepatic steatosis, hepatic fibrosis and dietary composition in these NAFLD patients.

METHODS

In vivo site-specific IP was analysed with a validated multi-sugar test in NAFLD patients and HC. Furthermore, in NAFLD patients, hepatic steatosis (chemical shift MRI), hepatic fibrosis (transient elastography) and dietary composition (food frequency questionnaire) were assessed.

RESULTS

Fifty-two NAFLD patients and forty-six HC were included in this study. Small intestinal (P <0.001), colonic (P = 0.004) and whole gut (P <0.001) permeability were increased in NAFLD patients compared to HC. Furthermore, colonic permeability (P = 0.029) was significantly higher in NAFLD patients with clinically significant fibrosis compared to those without. Colonic permeability remained positively associated with the presence of clinically significant fibrosis (P = 0.017) after adjustment for age, sex and BMI.

CONCLUSION

Colonic permeability is increased in at least a subset of NAFLD patients compared to HC and is independently associated with clinically significant NAFLD fibrosis.

Do Patients' and Physicians' Perspectives Differ on Preferences for Irritable Bowel Syndrome Treatment?

Irritable bowel syndrome (IBS) is a highly prevalent disorder of gut-brain interaction and poses a significant burden to patients. Pharmacotherapy, diet, and psychotherapy all have largely comparable clinical efficacy. Therefore, factors outside efficacy can have an important impact in determining preferences for a specific therapeutic entity. The aim of this study was to compare the patient and physician perspectives and identify important treatment characteristics regarding the management of IBS. Semistructured interviews were performed among IBS patients (n = 8), fulfilling the Rome IV criteria, and surveys were sent to physicians involved in IBS care (n = 15). Nine important treatment characteristics were revealed: effectiveness, time until response, cessation of response, side effects, location, waiting period, treatment burden, frequency of healthcare appointments, and willingness to pay. Time to response, location, and waiting time were less important for patients compared to physicians. This study assessed important IBS treatment characteristics and provided context to preferences from a patient and physician perspective. These data could be relevant during shared decision-making in clinical practice.

Antroduodenal motility recording identifies characteristic patterns in gastroparesis related to underlying etiology

BACKGROUND

Gastroparesis (GP) is a gastrointestinal disorder associated with significant morbidity and healthcare costs. GP patients form a heterogeneous population with diverse etiology, and treatment is often challenging due to a poorly understood underlying pathophysiology. The aim of the present study was to assess antroduodenal motility patterns among the different GP etiologies.

METHODS

We reviewed antroduodenal manometry (ADM) recordings of patients with confirmed GP between 2009 and 2019. ADM measurements were evaluated for fed period duration, number of phase III contractions and migrating motor complexes (MMCs), motility index (MI), and presence of neuropathic patterns.

KEY RESULTS

A total of 167 GP patients (142 women, median age 45 [31-57]) were included. The following etiologies were identified: idiopathic n = 101; post-surgery n = 36; and diabetes n = 30. Fed period duration was significantly longer in idiopathic (p &lt; 0.01) and diabetic GP patients (p &lt; 0.05) compared with post-surgery GP patients. Furthermore, the number and duration of phase III contractions and the number of MMCs were significantly lower in idiopathic and diabetic patients compared with post-surgery GP patients (p &lt; 0.01). Likewise, absence of MMCs during 6-h recording was more often observed in idiopathic and diabetes GP patients compared with post-surgery GP patients (resp. p &lt; 0.01 and p &lt; 0.05).

CONCLUSIONS AND INFERENCES

Antroduodenal motility patterns are different among GP etiologies. A dysmotility spectrum was identified with different patterns ranging from post-surgery GP to idiopathic and diabetic GP.

Discrete Choice Experiment Reveals Strong Preference for Dietary Treatment Among Patients With Irritable Bowel Syndrome

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is a highly prevalent, chronic disorder of the gut-brain interaction that significantly affects quality of life. Several treatments, with comparable clinical efficacy, are available. Patient preferences can therefore be an important determinant of an effective management strategy. Treatment preferences of patients regarding decision making remain unclear. We aimed to examine these preferences and estimate trade-offs between different attributes.

METHODS

A total of 427 patients from the Maastricht IBS cohort were invited to participate. A labeled discrete choice experiment survey, containing 9 scenarios with each 3 alternatives (medication, diet, psychotherapy), was developed in order to estimate preferences. The treatment scenarios were based on 6 attributes: effectiveness, time to response, time until recurrence, side effects, time required, and frequency of appointments. The preference weights and relative importance were analyzed using a mixed logit model.

RESULTS

A total of 185 (43.3%) of 427 potential respondents completed the questionnaire (mean age 49.51 years, 69.2% female). The most preferred treatment was dietary intervention (48.1%), followed by pharmacotherapy (29.2%) and psychotherapy (22.7%). IBS patients preferred a higher effectiveness, shorter time interval to response, longer time interval until recurrence, no severe side effects, and frequent appointments when attending psychotherapy. Younger patients (≤50 years of age) preferred dietary interventions and a long period until recurrence, whereas older patients (&gt;50 years of age) were more inclined to choose pharmacotherapy and the period until recurrence was not important.

CONCLUSIONS

Dietary interventions were the most preferred IBS therapy. Identifying patients' treatment preferences during shared decision making will provide more optimal management strategies and could be the best approach to diminish disease burden.

Artificial intelligence in (gastrointestinal) healthcare: patients' and physicians' perspectives

Artificial intelligence (AI) is entering into daily life and has the potential to play a significant role in healthcare. Aim was to investigate the perspectives (knowledge, experience, and opinion) on AI in healthcare among patients with gastrointestinal (GI) disorders, gastroenterologists, and GI-fellows. In this prospective questionnaire study 377 GI-patients, 35 gastroenterologists, and 45 GI-fellows participated. Of GI-patients, 62.5% reported to be familiar with AI and 25.0% of GI-physicians had work-related experience with AI. GI-patients preferred their physicians to use AI (mean 3.9) and GI-physicians were willing to use AI (mean 4.4, on 5-point Likert-scale). More GI-physicians believed in an increase in quality of care (81.3%) than GI-patients (64.9%, χ²(2) = 8.2, p = 0.017). GI-fellows expected AI implementation within 6.0 years, gastroenterologists within 4.2 years (t(76) =  − 2.6, p = 0.011), and GI-patients within 6.1 years (t(193) =  − 2.0, p = 0.047). GI-patients and GI-physicians agreed on the most important advantages of AI in healthcare: improving quality of care, time saving, and faster diagnostics and shorter waiting times. The most important disadvantage for GI-patients was the potential loss of personal contact, for GI-physicians this was insufficiently developed IT infrastructures. GI-patients and GI-physicians hold positive perspectives towards AI in healthcare. Patients were significantly more reserved compared to GI-fellows and GI-fellows were more reserved compared to gastroenterologists.

Evidence for engagement of the nucleus of the solitary tract in processing intestinal chemonociceptive input irrespective of conscious pain response in healthy humans

ABSTRACT

Neuroimaging studies have revealed important pathomechanisms related to disorders of brain-gut interactions, such as irritable bowel syndrome and functional dyspepsia. More detailed investigations aimed at neural processing in the brainstem, including the key relay station of the nucleus of the solitary tract (NTS), have hitherto been hampered by technical shortcomings. To ascertain these processes in more detail, we used multiecho multiband 7T functional magnetic resonance imaging and a novel translational experimental model based on a nutrient-derived intestinal chemonociceptive stimulus. In a randomized cross-over fashion, subjects received duodenal infusion of capsaicin (the pungent principle in red peppers) and placebo (saline). During infusion, functional magnetic resonance imaging data and concomitant symptom ratings were acquired. Of 26 healthy female volunteers included, 18 were included in the final analysis. Significantly increased brain activation over time during capsaicin infusion, as compared with placebo, was observed in brain regions implicated in pain processing, in particular the NTS. Brain activation in the thalamus, cingulate cortex, and insula was more pronounced in subjects who reported abdominal pain (visual analogue scale > 10 mm), as compared with subjects who experienced no pain. On the contrary, activations at the level of the NTS were independent of subjective pain ratings. The current experimental paradigm therefore allowed us to demonstrate activation of the principal relay station for visceral afferents in the brainstem, the NTS, which was engaged irrespective of the conscious pain response. These findings contribute to understanding the fundamental mechanism necessary for developing novel therapies aimed at correcting disturbances in visceral afferent pain processing.

Electrolyte disturbances after bowel preparation for colonoscopy: Systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

We conducted a systematic review and meta-analysis of population-based studies to explore pooled prevalence and magnitude of electrolyte changes after bowel preparation for colonoscopy based on the most recent guidelines.

PATIENTS AND METHODS

PubMed and Cochrane were queried for population-based studies examining changes in electrolyte values after bowel preparation, published by July 1, 2021. We report prevalences of serum hypokalemia, hyponatremia, hyperphosphatemia, and hypocalcemia after bowel preparation and changes in mean electrolyte values after vs. before bowel preparation using sodium phosphate (NaP) and polyethylene glycol (PEG).

RESULTS

Thirteen studies met the inclusion criteria; 2386 unique patients were included. Overall, hypokalemia was found in 17.2% (95% CI 6.7, 30.9) in the NaP group vs. 4.8% (95% CI 0.27, 13.02) in the PEG group. The magnitude of potassium decrease after NaP bowel preparation was significantly increased compared to PEG (mean difference -0.38; 95% CI -0.49 to -0.27, P < 0.001). No study reported on major complications.

CONCLUSIONS

Hypokalemia was found in 17.2% of patients after bowel preparation with NaP and in 4.8% of patients with PEG, a finding that is clinically relevant with respect to choosing the type of bowel preparation. The magnitude of the potassium decrease after NaP was significantly higher compared to PEG. These data provide the evidence that supports the recommendation of the European Society of Gastrointestinal Endoscopy against routine use of NaP for bowel preparation.

Lessons From a Systematic Literature Search on Diagnostic DNA Methylation Biomarkers for Colorectal Cancer: How to Increase Research Value and Decrease Research Waste?

OBJECTIVES

To improve colorectal cancer (CRC) survival and lower incidence rates, colonoscopy and/or fecal immunochemical test screening are widely implemented. Although candidate DNA methylation biomarkers have been published to improve or complement the fecal immunochemical test, clinical translation is limited. We describe technical and methodological problems encountered after a systematic literature search and provide recommendations to increase (clinical) value and decrease research waste in biomarker research. In addition, we present current evidence for diagnostic CRC DNA methylation biomarkers.

METHODS

A systematic literature search identified 331 diagnostic DNA methylation marker studies published before November 2020 in PubMed, EMBASE, Cochrane Library, and Google Scholar. For 136 bodily fluid studies, extended data extraction was performed. STARD criteria and level of evidence were registered to assess reporting quality and strength for clinical translation.

RESULTS

Our systematic literature search revealed multiple issues that hamper the development of DNA methylation biomarkers for CRC diagnosis, including methodological and technical heterogeneity and lack of validation or clinical translation. For example, clinical translation and independent validation were limited, with 100 of 434 markers (23%) studied in bodily fluids, 3 of 434 markers (0.7%) translated into clinical tests, and independent validation for 92 of 411 tissue markers (22%) and 59 of 100 bodily fluids markers (59%).

DISCUSSION

This systematic literature search revealed that major requirements to develop clinically relevant diagnostic CRC DNA methylation markers are often lacking. To avoid the resulting research waste, clinical needs, intended biomarker use, and independent validation should be better considered before study design. In addition, improved reporting quality would facilitate meta-analysis, thereby increasing the level of evidence and enabling clinical translation.

Genetic Profiling of Colorectal Carcinomas of Patients with Primary Sclerosing Cholangitis and Inflammatory Bowel Disease

BACKGROUND

Patients with primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) run a 10-fold increased risk of developing colorectal cancer (CRC) compared to patients with IBD only. The aim of this study was to perform an extensive screen of known carcinogenic genomic alterations in patients with PSC-IBD, and to investigate whether such changes occur already in nondysplastic mucosa.

METHODS

Archival cancer tissue and nondysplastic mucosa from resection specimens of 19 patients with PSC-IBD-CRC were characterized, determining DNA copy-number variations, microsatellite instability (MSI), mutations on 48 cancer genes, and CpG island methylator phenotype (CIMP). Genetic profiles were compared with 2 published cohorts of IBD-associated CRC (IBD-CRC; n = 11) and sporadic CRC (s-CRC; n = 100).

RESULTS

Patterns of chromosomal aberrations in PSC-IBD-CRC were similar to those observed in IBD-CRC and s-CRC, MSI occurred only once. Mutation frequencies were comparable between the groups, except for mutations in KRAS, which were less frequent in PSC-IBD-CRC (5%) versus IBD-CRC (38%) and s-CRC (31%; P = .034), and in APC, which were less frequent in PSC-IBD-CRC (5%) and IBD-CRC (0%) versus s-CRC (50%; P < .001). Cases of PSC-IBD-CRC were frequently CIMP positive (44%), at similar levels to cases of s-CRC (34%; P = .574) but less frequent than in cases with IBD-CRC (90%; P = .037). Similar copy number aberrations and mutations were present in matched cancers and adjacent mucosa in 5/15 and 7/11 patients, respectively.

CONCLUSIONS

The excess risk of CRC in patients with PSC-IBD was not explained by copy number aberrations, mutations, MSI, nor CIMP status, in cancer tissue, nor in adjacent mucosa. These findings set the stage for further exome-wide and epigenetic studies.

The Interplay Between Stress and Fullness in Patients With Functional Dyspepsia and Healthy Controls: An Exploratory Experience Sampling Method Study

OBJECTIVE

Fullness is a cardinal symptom in functional dyspepsia (FD). The use of real-time symptom assessment might provide more insight into factors, such as daily stress, that can influence fullness. Therefore, this study aimed to use the experience sampling method (a real-time, repeated-measurement method making use of repeated questionnaires available at random moments for a limited amount of time) to assess the association between stress and fullness in patients with FD and healthy controls (HCs).

METHODS

Thirty-five patients with FD (25 female, mean age = 44.7 years) and 34 HCs (24 female, mean age = 44.1 years) completed the experience sampling method (a maximum of 10 random moments per day) for 7 consecutive days. Stress and fullness were rated on an 11-point Numeric Rating Scale. Data between patients with FD and HCs were statistically compared using a Student samples t test and linear mixed-effects models with repeated measures (level 1) nested within participants (level 2).

RESULTS

Average fullness scores were 2.23 (standard error = 0.37) points higher in patients with FD compared with HCs (p < .001). Average stress scores were 1.37 (standard error = 0.30) points higher in patients with FD compared with HCs (p = .002).In FD, fullness scores increased with 0.14 for every 1-point increase in concurrent stress scores (p = .010). Fullness scores at t = 0 increased with 0.12 for every 1-point increase in stress scores at t = -1 (p = .019). T = 0 stress scores were not associated with change in t = -1 fullness scores. No associations between concurrent symptom scores were found for HCs.

CONCLUSIONS

Concurrent and preceding stress scores are positively associated with fullness scores in patients with FD, but not in HCs. These findings indicate that increased levels of stress may precede feelings of fullness in patients with FD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04204421.

Commonly used biomarkers do not contribute to diagnosing irritable bowel syndrome

OBJECTIVE

The aim of this article was to examine the costs and effectiveness of standardized blood and fecal investigations in patients fulfilling the Rome criteria for irritable bowel syndrome (IBS).

METHODS

We conducted a real-life cohort study in patients fulfilling the Rome III criteria for IBS without red flag signs or symptoms, in a center of excellence for IBS patients from 1 January 2015 till 1 January 2019. Standardized blood and fecal investigations [hemoglobin (Hb), thyroid-stimulating hormone (TSH), coeliac serology, and fecal calprotectin (FCP)] were performed during the first consultation. Patients were followed for at least 1 year. Primary outcome was the probability of another diagnosis than IBS with subsequent overall costs.

RESULTS

A total of 218 patients were included. In approximately 200 patients blood and fecal investigations were performed and 47 patients underwent a colonoscopy. Two-hundred ten patients were diagnosed with IBS, 5 with inflammatory bowel disease (IBD), 1 with nonspecific acute ileitis, 1 with hyperthyroidism, and 1 with coeliac disease. The number needed to diagnose all included laboratory tests was 34, and for the individual test: TSH 197, coeliac serology 199, and FCP 50. The total costs were approximately €4900 to diagnose one patient with another diagnosis than IBS.

CONCLUSION

In our real-life cohort of adult patients under the age of 50 years fulfilling the Rome criteria for IBS without red flag symptoms, standardized blood, and fecal investigations have a very low diagnostic yield accompanied by high additional costs. Colonoscopy is not indicated in patients with Rome III positive IBS and normal FCP.

Age-Related Decrease in Abdominal Pain and Associated Structural- and Functional Mechanisms: An Exploratory Study in Healthy Individuals and Irritable Bowel Syndrome Patients

Introduction: The world population is ageing, resulting in increased prevalence of age-related comorbidities and healthcare costs. Limited data are available on intestinal health in elderly populations. Structural and functional changes, including altered visceroperception, may lead to altered bowel habits and abdominal symptoms in healthy individuals and irritable bowel syndrome (IBS) patients. Our aim was to explore age-related changes in gastrointestinal symptoms and underlying mechanisms. Methods: In total, 780 subjects (IBS patients n = 463, healthy subjects n = 317) from two separate studies were included. Subjects were divided into different age groups ranging from young adult to elderly. Demographics and gastrointestinal symptom scores were collected from all participants using validated questionnaires. A subset of 233 IBS patients and 103 controls underwent a rectal barostat procedure to assess visceral hypersensitivity. Sigmoid biopsies were obtained from 10 healthy young adults and 10 healthy elderly. Expression of the visceral pain-associated receptors transient receptor potential (TRP) Ankyrin 1 (TRPA1) and Vanilloid 1 (TRPV1) genes were investigated by quantitative RT-PCR and immunofluorescence. Results: Both elderly IBS and healthy individuals showed significantly lower scores for abdominal pain (p < 0.001) and indigestion (p < 0.05) as compared to respective young adults. Visceral hypersensitivity was less common in elderly than young IBS patients (p < 0.001). Relative TRPA1 gene transcription, as well as TRPA1 and TRPV1 immunoreactivity were significantly lower in healthy elderly versus healthy young adults (p < 0.05). Conclusions: Our findings show an age-related decrease in abdominal pain perception. This may in part be related to decreased TRPA1 and/or TRPV1 receptor expression. Further studies are needed to reveal precise underlying mechanisms and the associations with intestinal health.

Molecular pathways in post-colonoscopy versus detected colorectal cancers: results from a nested case-control study

BACKGROUND

Post-colonoscopy colorectal cancers (PCCRCs) pose challenges in clinical practice. PCCRCs occur due to a combination of procedural and biological causes. In a nested case-control study, we compared clinical and molecular features of PCCRCs and detected CRCs (DCRCs).

METHODS

Whole-genome chromosomal copy number changes and mutation status of genes commonly affected in CRC were examined by low-coverage WGS and targeted sequencing, respectively. MSI and CIMP status was also determined.

RESULTS

In total, 122 PCCRCs and 98 DCRCs with high-quality DNA were examined. PCCRCs were more often located proximally (P < 0.001), non-polypoid appearing (P = 0.004), early stage (P = 0.009) and poorly differentiated (P = 0.006). PCCRCs showed significantly less 18q loss (FDR < 0.2), compared to DCRCs. No significant differences in mutations were observed. PCCRCs were more commonly CIMP high (P = 0.014) and MSI (P = 0.029). After correction for tumour location, only less 18q loss remained significant (P = 0.005).

CONCLUSION

Molecular features associated with the sessile serrated lesions (SSLs) and non-polypoid colorectal neoplasms (CRNs) are more commonly seen in PCCRCs than in DCRCs. These together with the clinical features observed support the hypothesis that SSLs and non-polypoid CRNs are contributors to the development of PCCRCs. The future focus should be directed at improving the detection and endoscopic removal of these non-polypoid CRN and SSLs.

CLINICAL TRIAL REGISTRATION

NTR3093 in the Dutch trial register ( www.trialregister.nl ).

Optical diagnosis of colorectal polyp images using a newly developed computer-aided diagnosis system (CADx) compared with intuitive optical diagnosis

BACKGROUND

Optical diagnosis of colorectal polyps remains challenging. Image-enhancement techniques such as narrow-band imaging and blue-light imaging (BLI) can improve optical diagnosis. We developed and prospectively validated a computer-aided diagnosis system (CADx) using high-definition white-light (HDWL) and BLI images, and compared the system with the optical diagnosis of expert and novice endoscopists.

METHODS

CADx characterized colorectal polyps by exploiting artificial neural networks. Six experts and 13 novices optically diagnosed 60 colorectal polyps based on intuition. After 4 weeks, the same set of images was permuted and optically diagnosed using the BLI Adenoma Serrated International Classification (BASIC).

RESULTS

CADx had a diagnostic accuracy of 88.3 % using HDWL images and 86.7 % using BLI images. The overall diagnostic accuracy combining HDWL and BLI (multimodal imaging) was 95.0 %, which was significantly higher than that of experts (81.7 %, P = 0.03) and novices (66.7 %, P < 0.001). Sensitivity was also higher for CADx (95.6 % vs. 61.1 % and 55.4 %), whereas specificity was higher for experts compared with CADx and novices (95.6 % vs. 93.3 % and 93.2 %). For endoscopists, diagnostic accuracy did not increase when using BASIC, either for experts (intuition 79.5 % vs. BASIC 81.7 %, P = 0.14) or for novices (intuition 66.7 % vs. BASIC 66.5 %, P = 0.95).

CONCLUSION

CADx had a significantly higher diagnostic accuracy than experts and novices for the optical diagnosis of colorectal polyps. Multimodal imaging, incorporating both HDWL and BLI, improved the diagnostic accuracy of CADx. BASIC did not increase the diagnostic accuracy of endoscopists compared with intuitive optical diagnosis.