Quality of reporting inflammatory bowel disease randomised controlled trials: a systematic review

OBJECTIVE

Our objective was to perform a systemic evaluation of the risk of bias in randomised controlled trial (RCT) reports published on inflammatory bowel disease (IBD).

DESIGN

We assessed the risk of bias using the Cochrane tool, as indicators of poor methodology or subsequently poor reporting. We systematically selected, with dual independent judgements, all studies published on IBD with no time limits and assessed the methodological quality of included studies again using independent dual ratings.

RESULTS

563 full texts were included after selection and review. No abstract publications were free of any source of bias. Full-text publications still fared badly, as only 103 full-text papers exhibited a low risk of bias in all reporting domains when excluding blinding. RCTs published in journals with higher impact factor (IF) were associated with an overall reduced rate of being at high risk. However, only 6% of full RCT publications in journals with an IF greater than 10, published in the past 5 years, were free of bias.The trend over time is towards improved reporting in all areas. Trials published by larger author teams, in full-text form and by industry and public sponsorship were positively correlated with a lower risk of bias. Only allocation concealment showed a statistically significant improvement with time (p=0.037).

CONCLUSION

These findings are consistent with those of other specialties in the literature. While this unclear risk of bias may represent poor reporting of methods instead of poor methodological quality, it leaves readers and future secondary researchers with significant questions regarding such key issues.

Milk fat globule-epidermal growth factor 8 (MFGE8) prevents intestinal fibrosis

OBJECTIVE

Intestinal fibrosis is considered an inevitable consequence of chronic IBD, leading to stricture formation and need for surgery. During the process of fibrogenesis, extracellular matrix (ECM) components critically regulate the function of mesenchymal cells. We characterised the composition and function of ECM in fibrostenosing Crohn's disease (CD) and control tissues.

DESIGN

Decellularised full-thickness intestinal tissue platforms were tested using three different protocols, and ECM composition in different tissue phenotypes was explored by proteomics and validated by quantitative PCR (qPCR) and immunohistochemistry. Primary human intestinal myofibroblasts (HIMFs) treated with milk fat globule-epidermal growth factor 8 (MFGE8) were evaluated regarding the mechanism of their antifibrotic response, and the action of MFGE8 was tested in two experimental intestinal fibrosis models.

RESULTS

We established and validated an optimal decellularisation protocol for intestinal IBD tissues. Matrisome analysis revealed elevated MFGE8 expression in CD strictured (CDs) tissue, which was confirmed at the mRNA and protein levels. Treatment with MFGE8 inhibited ECM production in normal control HIMF but not CDs HIMF. Next-generation sequencing uncovered functionally relevant integrin-mediated signalling pathways, and blockade of integrin αvβ5 and focal adhesion kinase rendered HIMF non-responsive to MFGE8. MFGE8 prevented and reversed experimental intestinal fibrosis in vitro and in vivo.

CONCLUSION

MFGE8 displays antifibrotic effects, and its administration may represent a future approach for prevention of IBD-induced intestinal strictures.

Early-life exposures and the microbiome: implications for IBD prevention

The early-life period is one of microbiome establishment and immune maturation. Early-life exposures are increasingly being recognised to play an important role in IBD risk. The composition of functions of the gut microbiome in the prenatal, perinatal, and postnatal period may be crucial towards development of health or disease, including IBD, later in life. We herein present a comprehensive summary of the interplay between early-life factors and microbiome perturbations, and their association with risk of IBD. In addition, we provide an overview of host and external factors in early life that are known to impact gut microbiome maturation and exposures implicated in IBD risk. Considering the emerging concept of IBD prevention, we propose strategies to minimise maternal and offspring exposure to potentially harmful variables and recommend protective measures during pregnancy and the postpartum period. This holistic view of early-life factors and microbiome signatures among mothers and their offspring will help frame our current understanding of their importance towards IBD pathogenesis and frame the roadmap for preventive strategies.

Biological therapy for inflammatory bowel disease: cyclical rather than lifelong treatment?

Inflammatory bowel disease (IBD) treatment was revolutionised with the arrival of biological therapy two decades ago. There are now multiple biologics and increasingly novel small molecules licensed for the treatment of IBD. Treatment guidelines highlight the need for effective control of inflammation and early escalation to advanced therapies to avoid long-term complications. Consequently, a large proportion of patients with IBD receive advanced therapies for a long time. Despite their beneficial risk-benefit profile, these treatments are not without risk of side effects, are costly to healthcare providers and pose a burden to the patient. It is, therefore, paramount to examine in which circumstances a temporary cessation of therapy can be attempted without undue clinical risk. Some patients may benefit from cyclical rather than continuous treatment. This review examines the risk of relapse after discontinuation of advanced therapies, how to identify patients at the lowest risk of relapse and the chance of recapturing response when flaring after discontinuation.

Controversies in the management of anti-TNF therapy in patients with Crohn's disease: a Delphi consensus

BACKGROUND

Despite research, there are still controversial areas in the management of Crohn's disease (CD).

OBJECTIVE

To establish practical recommendations on using anti-tumour necrosis factor (TNF) drugs in patients with moderate-to-severe CD.

METHODS

Clinical controversies in the management of CD using anti-TNF therapies were identified. A comprehensive literature review was performed, and a national survey was launched to examine current clinical practices when using anti-TNF therapies. Their results were discussed by expert gastroenterologists within a nominal group meeting, and a set of statements was proposed and tested in a Delphi process.

RESULTS

Qualitative study. The survey and Delphi process were sent to 244 CD-treating physicians (response rate: 58%). A total of 14 statements were generated. All but two achieved agreement. These statements cover: (1) use of first-line non-anti-TNF biological therapy; (2) role of HLA-DQA1*05 in daily practice; (3) attitudes in primary non-response and loss of response to anti-TNF therapy due to immunogenicity; (4) use of ustekinumab or vedolizumab if a change in action mechanism is warranted; (5) anti-TNF drug level monitoring; (6) combined therapy with an immunomodulator.

CONCLUSION

This document sought to pull together the best evidence, experts' opinions, and treating physicians' attitudes when using anti-TNF therapies in patients with CD.

JAK inhibitors for inflammatory bowel disease: recent advances

Inflammatory bowel disease (IBD) commonly requires immunosuppressive treatments to induce and maintain durable remission. Janus kinase inhibitors (JAKis) are a novel group of orally administered, small molecule drugs that work by attenuating multiple cytokine signalling pathways to mediate dysregulated immune responses involved in the pathogenesis of IBD. Tofacitinib, filgotinib and upadacitinib have demonstrated efficacy against placebo and are licensed for the treatment of moderate to severe ulcerative colitis; upadacitinib is the only JAKi also currently approved for the treatment of Crohn's disease. Safety concerns stratified by age have led to class-wide regulatory restrictions for JAKi use across all inflammatory diseases. It is important for gastroenterologists managing patients with IBD to be aware of the key pivotal trial outcomes, to identify appropriate patients in whom to commence a JAKi, and to understand the safety considerations and ways to mitigate these risks in the patients they treat. This review provides a contemporaneous overview of this emerging therapeutic class and provides a practical guide for healthcare practitioners for initiating and monitoring JAKi in IBD.

People with IBD evidence more microarousals during sleep architecture assessments

OBJECTIVE

Poor sleep is common in inflammatory bowel disease (IBD) and may be associated with overall worse disease outcomes. While the sleep/IBD literature is growing, the data are often self-reported. Further, much of the research using objective measures of sleep architecture, or the overall pattern of sleep depth, rely on single-night assessments, which can be of questionable validity.

DESIGN

Participants with IBD and healthy controls were recruited from Dartmouth-Hitchcock Medical Center as part of a two-phase clinical trial. Sleep architecture was assessed using three nights of in-home electroencephalographic monitoring and scored according to the American Academy of Sleep Medicine guidelines.

RESULTS

Our sample included 15 participants with IBD and 8 healthy controls. Participants with IBD were more psychiatrically complex, with more self-reported insomnia, anxiety and depression. Participants with IBD evidenced greater microarousals than healthy controls. In participants with IBD, microarousals were associated with lower insomnia and greater depression scores. Within IBD, participants with clinically significant insomnia evidenced trend towards lower sleep efficiency, while self-reported disease activity did not significantly impact findings.

CONCLUSIONS

The methodology of past research may have impacted findings, including the reliance on single-night assessments and limited generalisability. Future research that uses robust, multinight assessments of sleep architecture in large, diverse samples is clearly warranted, as is research exploring the impact of cognitive and behavioural factors on sleep architecture and arousal.

TRIAL REGISTRATION NUMBER

NCT04132024.

Chronic abdominal pain in inflammatory bowel disease: a practical guide

Pain is common in inflammatory bowel disease (IBD), yet many patients feel their pain is not addressed by healthcare professionals. Listening to a patient's concerns about pain, assessing symptoms and acknowledging the impact these have on daily life remain crucial steps in addressing pain in IBD. While acute pain may be effectively controlled by pain medication, chronic pain is more complex and often pharmacological therapies, particularly opioids, are ineffective. Low-dose tricyclic antidepressants and psychological approaches, including cognitive-behavioural therapy, have shown some promise in offering effective pain management while lifestyle changes such as a trial of low-fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet in those with overlapping irritable bowel syndrome may also reduce pain. Patients benefit from a long-term, trusting relationship with their healthcare professional to allow a holistic approach combining pharmacological, psychological, lifestyle and dietary approaches to chronic pain. We present a practical review to facilitate management of chronic abdominal pain in IBD.

Faecal metabolome and its determinants in inflammatory bowel disease

OBJECTIVE

Inflammatory bowel disease (IBD) is a multifactorial immune-mediated inflammatory disease of the intestine, comprising Crohn's disease and ulcerative colitis. By characterising metabolites in faeces, combined with faecal metagenomics, host genetics and clinical characteristics, we aimed to unravel metabolic alterations in IBD.

DESIGN

We measured 1684 different faecal metabolites and 8 short-chain and branched-chain fatty acids in stool samples of 424 patients with IBD and 255 non-IBD controls. Regression analyses were used to compare concentrations of metabolites between cases and controls and determine the relationship between metabolites and each participant's lifestyle, clinical characteristics and gut microbiota composition. Moreover, genome-wide association analysis was conducted on faecal metabolite levels.

RESULTS

We identified over 300 molecules that were differentially abundant in the faeces of patients with IBD. The ratio between a sphingolipid and L-urobilin could discriminate between IBD and non-IBD samples (AUC=0.85). We found changes in the bile acid pool in patients with dysbiotic microbial communities and a strong association between faecal metabolome and gut microbiota. For example, the abundance of Ruminococcus gnavus was positively associated with tryptamine levels. In addition, we found 158 associations between metabolites and dietary patterns, and polymorphisms near NAT2 strongly associated with coffee metabolism.

CONCLUSION

In this large-scale analysis, we identified alterations in the metabolome of patients with IBD that are independent of commonly overlooked confounders such as diet and surgical history. Considering the influence of the microbiome on faecal metabolites, our results pave the way for future interventions targeting intestinal inflammation.

Immune response and barrier dysfunction-related proteomic signatures in preclinical phase of Crohn's disease highlight earliest events of pathogenesis

OBJECTIVE

The measure of serum proteome in the preclinical state of Crohn's disease (CD) may provide insight into biological pathways involved in CD pathogenesis. We aimed to assess associations of serum proteins with future CD onset and with other biomarkers predicting CD risk in a healthy at-risk cohort.

DESIGN

In a nested case-control study within the Crohn's and Colitis Canada Genetics Environment Microbial Project (CCC-GEM) cohort, which prospectively follows healthy first-degree relatives (FDRs), subjects who developed CD (n=71) were matched with four FDRs remaining healthy (n=284). Using samples at recruitment, serum protein profiles using the Olink Proximity Extension Assay platform was assessed for association with future development of CD and with other baseline biomarkers as follows: serum antimicrobial antibodies (AS: positive antibody sum) (Prometheus); faecal calprotectin (FCP); gut barrier function using the fractional excretion of lactulose-to-mannitol ratio (LMR) assay.

RESULTS

We identified 25 of 446 serum proteins significantly associated with future development of CD. C-X-C motif chemokine 9 (CXCL9) had the highest OR with future risk of CD (OR=2.07 per SD, 95% CI 1.58 to 2.73, q=7.9e-5), whereas matrix extracellular phosphoglycoprotein had the lowest OR (OR 0.44, 95% CI 0.29 to 0.66, q=0.02). Notably, CXCL9 was the only analyte significantly associated with all other CD-risk biomarkers with consistent direction of effect (FCP: OR=2.21; LMR: OR=1.67; AS: OR=1.59) (q<0.05 for all).

CONCLUSION

We identified serum proteomic signatures associated with future CD development, reflecting potential early biological processes of immune and barrier dysfunction.

Clinical advances: pregnancy in gastroenterologic and hepatic conditions

The fields of gastroenterology and hepatology, along with endoscopic practice, have seen significant changes and innovations to practice in just the past few years. These practice changes are not limited to gastroenterology, but maternal fetal medicine and the care of the pregnant person have become increasingly more sophisticated as well. Gastroenterologists are frequently called on to provide consultative input and/or perform endoscopy during pregnancy. To be able to provide the best possible care to these patients, gastroenterologists need to be aware of (and familiar with) the various nuances and caveats related to the care of pregnant patients who either have underlying gastrointestinal (GI) conditions or present with GI and liver disorders. Here, we offer a clinical update with references more recent than 2018, along with a few words about SARS-CoV-2 infection and its relevance to pregnancy.

Role of adherent and invasive Escherichia coli in Crohn's disease: lessons from the postoperative recurrence model

OBJECTIVE

We used the postoperative recurrence model to better understand the role of adherent and invasive Escherichia coli (AIEC) bacteria in Crohn's disease (CD), taking advantage of a well-characterised postoperative cohort.

DESIGN

From a prospective, multicentre cohort of operated patients with CD, AIEC identification was performed within the surgical specimen (M0) (N=181 patients) and the neoterminal ileum (n=119 patients/181) during colonoscopy performed 6 months after surgery (M6). Endoscopic postoperative recurrence was graded using Rutgeerts' index. The mucosa-associated microbiota was analysed by 16S sequencing at M0 and M6. Relative risks or ORs were adjusted on potential confounders.

RESULTS

AIEC prevalence was twofold higher within the neoterminal ileum at M6 (30.3%) than within the surgical specimen (14.9%) (p<0.001). AIEC within the neoterminal ileum at M6 was associated with higher rate of early ileal lesions (i1) (41.6% vs 17.1%; aRR 3.49 (95% CI 1.01 to 12.04), p=0.048) or ileal lesions (i2b+i3) (38.2% vs 17.1%; aRR 3.45 (95% CI 1.06 to 11.30), p=0.040) compared with no lesion (i0). AIEC within the surgical specimen was predictive of higher risk of i2b-endoscopic postoperative recurrence (POR) (aOR 2.54 (95% CI 1.01 to 6.44), p=0.049) and severe endoscopic POR (aOR 3.36 (95% CI 1.25 to 9.06), p=0.017). While only 5.0% (6/119) of the patients were AIEC-positive at both M0 and M6, 43.7% (52/119), patients with history of positive test for AIEC (M0 or M6) had higher risk of ileal endoscopic POR (aOR 2.32 (95% CI 1.01 to 5.39), p=0.048)), i2b-endoscopic postoperative recurrence (aOR 2.41 (95% CI 1.01 to 5.74); p=0.048) and severe endoscopic postoperative (aOR=3.84 (95% CI 1.32 to 11.18), p=0.013). AIEC colonisation was associated with a specific microbiota signature including increased abundance of Ruminococcus gnavus.

CONCLUSION

Based on the postoperative recurrence model, our data support the idea that AIEC are involved in the early steps of ileal CD.

TRIAL REGISTRATION NUMBER

NCT03458195.

Obesity among those newly diagnosed with Crohn's disease and ulcerative colitis compared with the general population

Objective

Obesity is a potentially modifiable risk factor for inflammatory bowel disease (IBD). We aimed to evaluate the body mass index (BMI) of those diagnosed with IBD early versus late in life in the context of age-adjusted background population.

Design/method

Patients with a new diagnosis of IBD from 2000 to 2021 were included. Early-onset IBD was classified as age <18 and late-onset IBD classified as age ≥65. Obesity was classified as BMI ≥30 kg/m2. Population data were obtained from community surveys.

Results

Included were 1573 patients (56.0%) with Crohn's disease (CD) and 1234 (44.0%) with ulcerative colitis (UC). Overall, the median BMI at IBD diagnosis was 20 kg/m2 (IQR 18-24) among those diagnosed at age <18 vs 26.9 kg/m2 (IQR 23.1-30.0) among those diagnosed at age ≥65 (rank-sum p<0.01). In all age groups, BMI was stable during the 1-year preceding IBD diagnosis. At age <18, 11.5% of the background population was obese compared with 3.8% of those with newly diagnosed CD (p<0.01) and 4.8% of those with newly diagnosed UC (p=0.05). At age ≥65, 23.6% of the population was obese compared with 24.3% of those with newly diagnosed CD (p=0.78) and 29.5% of those with newly diagnosed UC (p=0.01).

Conclusion

Patients with IBD diagnosed at age <18 were less likely to be obese compared with the age-adjusted background population whereas those diagnosed at age ≥65 were more likely to be obese. Future prospective studies should investigate obesity as a modifiable risk factor for late-life IBD.

Recent advances in clinical practice: advances in cross-sectional imaging in inflammatory bowel disease

Endoscopy remains the reference standard for the diagnosis and assessment of patients with inflammatory bowel disease (IBD), but it has several important limitations. Cross-sectional imaging techniques such as magnetic resonance enterography (MRE) and intestinal ultrasound (IUS) are better tolerated and safer. Moreover, they can examine the entire bowel, even in patients with stenoses and/or severe inflammation. A variety of cross-sectional imaging activity scores strongly correlate with endoscopic measures of mucosal inflammation in the colon and terminal ileum. Unlike endoscopy, cross-sectional techniques allow complete visualisation of the small-bowel and assess for extraintestinal disease, which occurs in nearly half of patients with IBD. Extramural findings may predict outcomes better than endoscopic mucosal assessment, so cross-sectional techniques might help identify more relevant therapeutic targets. Coupled with their high sensitivity, these advantages have made MRE and IUS the primary non-invasive options for diagnosing and monitoring Crohn's disease; they are appropriate first-line investigations, and have become viable alternatives to colonoscopy. This review discusses cross-sectional imaging in IBD in current clinical practice as well as research lines that will define the future role of these techniques.

Satisfaction with telemedicine-delivered inflammatory bowel disease care depends on disease activity, personality and economic factors

Objective

Patients with inflammatory bowel disease (IBD) traditionally receive follow-up care at face-to-face outpatient clinics. During the COVID-19 pandemic, gastroenterology societies recommended IBD clinics to be carried out remotely where possible using telephone or telemedicine-delivered virtual clinics. Previous studies have demonstrated patient satisfaction with virtual clinics but few studies have examined factors that impact satisfaction or assessed patient's personal perception of the virtual clinic experience.

Design/method

Patients who had their IBD clinic appointment changed from face-to-face to telephone virtual clinic completed a questionnaire relating to their clinical experience and preference for future care. Qualitative data were also collected and evaluated using content analysis to identify major themes associated with the patient experience.

Results

141 patients were included for analysis. The virtual clinic satisfaction questionnaire was found to be valid while patients expressed high-satisfaction levels with virtual clinics (median satisfaction score 18, range 0-20). Multivariate analysis identified open personality type (p=0.004), short disease duration (p=0.047) and higher cost to attend clinic (p=0.047) as predictors of high-satisfaction levels, with active disease (p=0.035) and an agreeable personality type (p=0.042) associated with low satisfaction levels. Content analysis of the qualitative data identified three major themes connected to virtual clinic convenience, lack of physical interaction and disease activity.

Conclusion

Patients expressed high levels of satisfaction with telemedicine-delivered IBD clinics, with most wishing to continue their use. Personality type should be recognised as an important variable affecting clinical satisfaction, in addition to socioeconomic and disease-related factors.

Decreased risk of treatment failure with vedolizumab and thiopurines combined compared with vedolizumab monotherapy in Crohn's disease

OBJECTIVE

While infliximab combined to thiopurines is more effective than infliximab monotherapy in patients with Crohn's disease (CD) and UC, the impact of adding thiopurines to vedolizumab remains controversial. We emulated two target trials comparing the effectiveness of combination therapy versus vedolizumab monotherapy in CD and UC.

DESIGN

Based on two US and the French nationwide healthcare databases, patients with CD and UC who initiated vedolizumab were identified. The study methodology, including confounding adjustment and outcome definitions, were previously validated in successful emulations of the SONIC and SUCCESS trials. Risk ratios for treatment failure based on hospitalisation or surgery related to disease activity, treatment switch, or prolonged corticosteroids use, were estimated after 1:1 propensity score (PS) matching.

RESULTS

Among a total of 10 299 vedolizumab users, 804 CD and 1088 UC pairs of combination therapy versus vedolizumab monotherapy users were PS matched. Treatment failure occurred at week 26 in 236 (29.3%) and 376 (34.3%) patients with CD and at week 16 in 236 (21.7%) and 263 (24.2%) patients with UC initiating combination therapy and vedolizumab monotherapy, respectively. The risk of treatment failure was decreased with combination therapy compared with vedolizumab monotherapy in CD (RR 0.85, 95% CI: 0.74 to 0.98) and to a lesser extent in UC (RR 0.90, 95% CI: 0.77 to 1.05). Findings were consistent across databases.

CONCLUSION

Using validated methodologies, combination therapy with vedolizumab and thiopurines was associated with lower treatment failure compared with vedolizumab monotherapy in CD but not UC across the USA and France.

Clinical procedures used to diagnose inflammatory bowel disease: real-world evidence from a Danish nationwide population-based study

Objective

Although clinical guidelines exist, the diagnostic work-up for diagnosing inflammatory bowel disease (IBD) is complex and varies in clinical practice. This study used real-life data to characterise the current diagnostic procedures used to establish IBD diagnoses in a Danish nationwide setting.

Design

Person-level data on patients diagnosed with IBD between 1 January 2014 and 30 June 2018 were linked between Danish health registers. Information on age, sex, registration of other gastrointestinal diseases, and diagnostic procedures (endoscopies, biopsies, and imaging) performed in relation to the first IBD hospital admission was analysed for the total study population and was stratified by IBD type, sex, and age.

Results

The majority of the 12 871 patients with IBD included underwent endoscopy (84%), had a biopsy taken (84%), and/or underwent imaging procedures (44%). In total, 7.5% of the population (6% for Crohn’s disease and 8% for ulcerative colitis) were diagnosed with IBD despite not undergoing any of these diagnostic procedures. Patients with Crohn’s disease underwent more procedures than patients with ulcerative colitis (94% vs 92%, p<0.001). Children underwent slightly fewer diagnostic procedures than adults (92% vs 93%, p=0.004). Slightly more men underwent at least one procedure than women (92% vs 94%, p<0.001).

Conclusion

For 7.5% of patients with IBD, this study did not detect any registrations of the recommended diagnostic procedures for establishing an IBD diagnosis. Further research is needed to examine whether these findings are mainly explained by limitations of the register data or also indicate shortcomings of the general approach to IBD.

Development and test-retest reliability of a new, self-report questionnaire assessing healthcare use and personal costs in people with inflammatory bowel disease: the Inflammatory Bowel Disease Resource Use Questionnaire (IBD-RUQ)

BACKGROUND AND AIMS

The increasing prevalence of inflammatory bowel disease (IBD) poses a substantial economic burden globally on health systems and societies. Validated instruments to collect data on healthcare and other service utilisation by patients with IBD are lacking. We developed a self-report patient questionnaire to capture key resource utilisation from health services, patient and societal perspectives.

METHODS

The IBD Resource Use Questionnaire (IBD-RUQ), developed by a multidisciplinary team, including patients, comprises 102 items across the six categories of outpatient visits, diagnostics, medication, hospitalisations, employment and out-of-pocket expenses over the past three months. The test-retest reliability of the IBD-RUQ was studied by administering it twice among patients with IBD with a 2-week time gap. The intraclass correlation coefficients and the average cost from the healthcare, societal and patient perspectives, between test and retest assessments, overall and by service category, were summarised.

RESULTS

The IBD-RUQ captures health service use, employment and out-of-pocket expenses. Of 55 patients who completed the first questionnaire, 48 completed the retest questionnaires and were included in the analyses. Test-retest reliability for categories of medications, diagnostics, specialist outpatient and inpatient services, and days off work due to IBD ranged from moderate to excellent; primary care visits showed more limited reliability. The annualised average self-reported health service, out-of-pocket and loss of productivity costs were £4844, £320 and £545 per patient, respectively.

CONCLUSIONS

The IBD-RUQ is a reliable and valid self-report measure of resource utilisation in adults with IBD and can be used to measure costs associated with IBD.

Appendectomy and risk for inflammatory bowel disease: effect of age and time post appendectomy - a cohort study

Background and objective

Appendectomy may modulate the risk of inflammatory bowel disease through an effect on the gut microbiota. This study investigated the associations between appendectomy and incidence of Crohn’s disease (CD) or ulcerative colitis (UC), with an emphasis on the influence of age and time post appendectomy.

Methods

This cohort study included 400 520 subjects born in Québec in 1970–1974 and followed until 2014. Administrative health data were used to ascertain appendectomy and cases of CD and UC. Cox proportional hazards models with time-dependent variables (appendectomy and time elapsed post appendectomy) allowed for the estimation of HRs and 95% CIs.

Results

A total of 2545 (0.6%) CD cases and 1134 (0.3%) UC cases were identified during follow-up. Appendectomy increased the risk of CD (HR=2.02; 95% CI: 1.66 to 2.44), especially when performed at 18–29 years of age. The risk of CD was increased in the first 2 years, and decreased significantly after ≥15 years post appendectomy. Appendectomy appeared to protect against UC (HR=0.39; 95% CI: 0.22 to 0.71). The risk of UC was not associated with age at appendectomy, but decreased with time elapsed post appendectomy (HR=0.21; 95% CI: 0.06 to 0.72, comparing ≥5 with 0–4 years after appendectomy).

Conclusions

The increased risk of CD related to appendectomy in young adults may result from detection bias, but physicians should have a low threshold for suspicion of CD in young symptomatic adults with a history of appendectomy. A strong protective effect of appendectomy against UC was observed after 5 years.

Lessons from an audit of exclusive enteral nutrition in adult inpatients and outpatients with active Crohn's disease: a single-centre experience

OBJECTIVE

To evaluate clinical outcomes, patterns of use, tolerance and nutritional outcomes of exclusive enteral nutrition (EEN) in adults with Crohn's disease and to compare initiation in the inpatient compared with ambulatory care setting.

DESIGN/METHOD

Adults with Crohn's disease who received EEN at a single centre over 2.5 years were identified and outcomes assessed via examination of patient records.

RESULTS

EEN was initiated in 60 patients (23 as an outpatient) who had objective evidence of active disease. Of 49 in whom the goal was induction of remission, 28 completed EEN and 24 achieved clinical remission/response. Twenty-one withdrew prematurely, due to intolerance in 15 and disease factors in 6. Of 11 with a planned intervention, 6 fulfilled the goal of downstaging disease while two were intolerant. Completion of the prescribed therapy was associated with self-reported adherence to EEN and with improvements in disease activity scores and biochemical markers. Malnutrition halved (40% to 20%) and intentional weight loss (median 5.1 kg) was achieved in six obese patients. The major reason for intolerance was the inability to accept total avoidance of non-formula food. There were no differences in any outcomes according to the location of initiation of therapy.

CONCLUSION

Positive outcomes occur in 70% of adult patients with Crohn's disease tolerating EEN and 81% in those who are able to completely adhere to EEN, without compromise of nutritional status. Similar success occurs when initiated as an inpatient or outpatient. Failure to tolerate EEN is the major hurdle to its use.

IBD therapeutics: what is in the pipeline?

Inflammatory bowel disease (IBD) is an idiopathic long-term relapsing and remitting disorder including ulcerative colitis and Crohn's disease. The aim of therapy is to induce and maintain remission. Anti-TNF therapies dramatically improved clinical outcomes but primary failure or secondary loss is a common problem as well as potential side effects potentially limiting efficacy and long-term use. The advent of new targeted agents with the potential for greater safety is welcomed in IBD and offers the potential for different agents as the disease becomes refractory or even combination therapies to maximise effectiveness without compromising safety in the future. More data are required to understand the best positioning in pathways and longer-term safety effects.

Are we addressing the top 10 research priorities in IBD?

BACKGROUND

Since publication of the top 10 research priorities in inflammatory bowel disease (IBD) based on the James Lind Alliance Priority Setting Partnership, the question remains whether this has influenced the IBD-research landscape. This study aimed to create an overview of the current distribution of research interests of trials in the UK.

METHODS

The ClinicalTrials.gov database and European Union Clinical Trials Register were screened for clinical trials set up from 9 August 2016 to 16 November 2019 in the UK involving adult patients with IBD.

RESULTS

Of 20 non-industry-sponsored studies, a quarter investigated treatment strategies considering efficacy, safety and cost-effectiveness (priority 1). Four evaluated the role of diet (priorities 3 and 7). Development/assessment of biomarkers for patient stratification (priority 2) and fatigue (priority 8) were subject of three studies. IBD-related pain and control of diarrhoea/incontinence were each subject of 2 studies (priorities 4 and 6). The effect of gut microbiota (priority 10) and optimal strategy for perianal Crohn's disease (priority 5) was the focus of 2 studies each. One study evaluated surgery for terminal ileal Crohn's disease (priority 9). Of 63 industry-sponsored studies, 59 focused on priority 1.

CONCLUSIONS

This study presents an impression of the breadth of the IBD-research landscape in the UK, in light of the top 10 research priorities published in 2016. Optimal treatment strategy has been the most studied research priority by academic and industry-sponsored trials. Fewer studies focused on patient-reported outcomes. It remains debatable to what extent the current research landscape adequately represents all stakeholders' viewpoints on needs for expanded knowledge in IBD, particularly the patients' perspective.

Pediatric Bone Mineral Accrual Z-Score Calculation Equations and Their Application in Childhood Disease

Annual gains in BMC and areal bone mineral density (aBMD) in children vary with age, pubertal status, height-velocity, and lean body mass accrual (LBM velocity). Evaluating bone accrual in children with bone health-threatening conditions requires consideration of these determinants. The objective of this study was to develop prediction equations for calculating BMC/aBMD velocity SD scores (velocity-Z) and to evaluate bone accrual in youth with health conditions. Bone and body compositions via DXA were obtained for up to six annual intervals in healthy youth (n = 2014) enrolled in the Bone Mineral Density in Childhood Study (BMDCS) . Longitudinal statistical methods were used to develop sex- and pubertal-status-specific reference equations for calculating velocity-Z for total body less head-BMC and lumbar spine (LS), total hip (TotHip), femoral neck, and 1/3-radius aBMD. Equations accounted for (1) height velocity, (2) height velocity and weight velocity, or (3) height velocity and LBM velocity. These equations were then applied to observational, single-center, 12-month longitudinal data from youth with cystic fibrosis (CF; n = 65), acute lymphoblastic leukemia (ALL) survivors (n = 45), or Crohn disease (CD) initiating infliximab (n = 72). Associations between BMC/aBMD-Z change (conventional pediatric bone health monitoring method) and BMC/aBMD velocity-Z were assessed. The BMC/aBMD velocity-Z for CF, ALL, and CD was compared with BMDCS. Annual changes in the BMC/aBMD-Z and the BMC/aBMD velocity-Z were strongly correlated, but not equivalent; LS aBMD-Z = 1 equated with LS aBMD velocity-Z = -3. In CF, BMC/aBMD velocity-Z was normal. In posttherapy ALL, BMC/aBMD velocity-Z was increased, particularly at TotHip (1.01 [-.047; 1.7], p < 0.0001). In CD, BMC/aBMD velocity-Z was increased at all skeletal sites. LBM-velocity adjustment attenuated these increases (eg, TotHip aBMD velocity-Z: 1.13 [0.004; 2.34] versus 1.52 [0.3; 2.85], p < 0.0001). Methods for quantifying the BMC/aBMD velocity that account for maturation and body composition changes provide a framework for evaluating childhood bone accretion and may provide insight into mechanisms contributing to altered accrual in chronic childhood conditions. © 2018 American Society for Bone and Mineral Research.

Practical guidance on the use of faecal calprotectin

Differentiation between inflammatory bowel disease (IBD) and functional gut disorders, and the determination of mucosal disease activity in established cases of IBD remain the cornerstones of disease diagnosis and management. Non-invasive, accurate biomarkers of gut inflammation are needed due to the variability of symptoms, the inaccuracies of currently available blood markers and the cost and invasive nature of endoscopy. Numerous biomarkers have been used and/or considered with some in current use. This article reviews the current evidence base around the indications for using biomarkers and their limitations, with a particular focus on faecal calprotectin.

Hypophosphatemia, Severe Bone Pain, Gait Disturbance, and Fatigue Fractures After Iron Substitution in Inflammatory Bowel Disease: A Case Report

Intravenous infusions of different iron formulations are recognized as a cause of hypophosphatemia. Chronic hypophosphatemia can alter bone metabolism and bone material structure. As a consequence, osteomalacia may develop and lead to bone fragility. Herein, we report a patient with Crohn's disease presenting with persistent hypophosphatemia and insufficiency fractures while receiving regular iron infusions due to chronic gastrointestinal bleeding. Previously, the patient regularly received vitamin D and also zoledronic acid. The patient underwent bone biopsy of the iliac crest that showed typical signs of osteomalacia with dramatically increased osteoid volume and decreased bone formation. Analysis of the bone mineralization density distribution (BMDD) revealed a more complex picture: On the one hand, there was a shift to higher matrix mineralization, presumably owing to low bone turnover; on the other hand, a broadening of the BMDD indicating more heterogeneous mineralization due to osteomalacia was also evident. This is the first report on changes of bone histomorphometry and bone matrix mineralization in iron-induced osteomalacia. © 2017 American Society for Bone and Mineral Research.

Development of an index to define overall disease severity in IBD

BACKGROUND AND AIM

Disease activity for Crohn's disease (CD) and UC is typically defined based on symptoms at a moment in time, and ignores the long-term burden of disease. The aims of this study were to select the attributes determining overall disease severity, to rank the importance of and to score these individual attributes for both CD and UC.

METHODS

Using a modified Delphi panel, 14 members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) selected the most important attributes related to IBD. Eighteen IOIBD members then completed a statistical exercise (conjoint analysis) to create a relative ranking of these attributes. Adjusted utilities were developed by creating proportions for each level within an attribute.

RESULTS

For CD, 15.8% of overall disease severity was attributed to the presence of mucosal lesions, 10.9% to history of a fistula, 9.7% to history of abscess and 7.4% to history of intestinal resection. For UC, 18.1% of overall disease severity was attributed to mucosal lesions, followed by 14.0% for impact on daily activities, 11.2% C reactive protein and 10.1% for prior experience with biologics. Overall disease severity indices were created on a 100-point scale by applying each attribute's average importance to the adjusted utilities.

CONCLUSIONS

Based on specialist opinion, overall CD severity was associated more with intestinal damage, in contrast to overall UC disease severity, which was more dependent on symptoms and impact on daily life. Once validated, disease severity indices may provide a useful tool for consistent assessment of overall disease severity in patients with IBD.

Molecular classification of Crohn's disease reveals two clinically relevant subtypes

OBJECTIVE

The clinical presentation and course of Crohn's disease (CD) is highly variable. We sought to better understand the cellular and molecular mechanisms that guide this heterogeneity, and characterise the cellular processes associated with disease phenotypes.

DESIGN

We examined both gene expression and gene regulation (chromatin accessibility) in non-inflamed colon tissue from a cohort of adult patients with CD and control patients. To support the generality of our findings, we analysed previously published expression data from a large cohort of treatment-naïve paediatric CD and control ileum.

RESULTS

We found that adult patients with CD clearly segregated into two classes based on colon tissue gene expression-one that largely resembled the normal colon and one where certain genes showed expression patterns normally specific to the ileum. These classes were supported by changes in gene regulatory profiles observed at the level of chromatin accessibility, reflective of a fundamental shift in underlying molecular phenotypes. Furthermore, gene expression from the ilea of a treatment-naïve cohort of paediatric patients with CD could be similarly subdivided into colon-like and ileum-like classes. Finally, expression patterns within these CD subclasses highlight large-scale differences in the immune response and aspects of cellular metabolism, and were associated with multiple clinical phenotypes describing disease behaviour, including rectal disease and need for colectomy.

CONCLUSIONS

Our results strongly suggest that these molecular signatures define two clinically relevant forms of CD irrespective of tissue sampling location, patient age or treatment status.

Efficacy of adalimumab in patients with Crohn's disease and symptomatic small bowel stricture: a multicentre, prospective, observational cohort (CREOLE) study

OBJECTIVE

The efficacy of anti-tumour necrosis factors (anti-TNFs) in patients with Crohn's disease (CD) and symptomatic small bowel stricture (SSBS) is controversial. The aim of this study was to estimate the efficacy of adalimumab in these patients and to identify the factors predicting success.

DESIGN

We performed a multicentre, prospective, observational cohort study in patients with CD and SSBS. The included patients underwent magnetic resonance enterography at baseline and subsequently received adalimumab. The primary endpoint was success at week 24, defined as adalimumab continuation without prohibited treatment (corticosteroids after the eight week following inclusion, other anti-TNFs), endoscopic dilation or bowel resection. The baseline factors independently associated with success were identified using a logistic regression model, leading to a simple prognostic score. Secondary endpoints were prolonged success after week 24 (still on adalimumab, without dilation nor surgery) and time to bowel resection in the whole cohort.

RESULTS

From January 2010 to December 2011, 105 patients were screened and 97 were included. At week 24, 62/97 (64%) patients had achieved success. The prognostic score defined a good prognosis group with 43/49 successes, an intermediate prognosis group with 17/28 successes and a poor prognosis group with 1/16 successes. After a median follow-up time of 3.8 years, 45.7%±6.6% (proportion±SE) of patients who were in success at week 24 (ie, 29% of the whole cohort) were still in prolonged success at 4 years. Among the whole cohort, 50.7%±5.3% of patients did not undergo bowel resection 4 years after inclusion.

CONCLUSIONS

A successful response to adalimumab was observed in about two-thirds of CD patients with SSBS and was prolonged in nearly half of them till the end of follow-up. More than half of the patients were free of surgery 4 years after treatment initiation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01183403; Results.

Can faecal calprotectin predict relapse in inflammatory bowel disease: a mini review

Crohn's disease and ulcerative colitis are chronic inflammatory disorders affecting the gastrointestinal tract. Faecal calprotectin is a protein complex of the S-100 family of calcium-binding proteins present in inflammatory cells that can be measured in stool samples, which act as a biomarker for bowel inflammation. Elevated faecal calprotectin has been shown to reflect the presence of ongoing mucosal inflammation, which improves with mucosal healing. The aim of this review was to evaluate the available evidence on the ability of faecal calprotectin to predict a relapse in inflammatory bowel disease. Multiple retrospective studies have shown that patients who relapse have significantly higher levels of calprotectin in their stool compared with non-relapsers, especially in ulcerative colitis. Elevated faecal calprotectin postoperatively in Crohn's disease was also shown to be indicative of a relapse. However, the association of a raised faecal calprotectin and relapse is not universal and may be explained by the different patterns of mucosal inflammatory activity that exist. In conclusion, we put forward our hypothesis that changes such as a rise in faecal calprotectin levels may be more predictive of a relapse than absolute values.

Uncoupling of mucosal gene regulation, mRNA splicing and adherent microbiota signatures in inflammatory bowel disease

OBJECTIVE

An inadequate host response to the intestinal microbiota likely contributes to the manifestation and progression of human inflammatory bowel disease (IBD). However, molecular approaches to unravelling the nature of the defective crosstalk and its consequences for intestinal metabolic and immunological networks are lacking. We assessed the mucosal transcript levels, splicing architecture and mucosa-attached microbial communities of patients with IBD to obtain a comprehensive view of the underlying, hitherto poorly characterised interactions, and how these are altered in IBD.

DESIGN

Mucosal biopsies from Crohn's disease and patients with UC, disease controls and healthy individuals (n=63) were subjected to microbiome, transcriptome and splicing analysis, employing next-generation sequencing. The three data levels were integrated by different bioinformatic approaches, including systems biology-inspired network and pathway analysis.

RESULTS

Microbiota, host transcript levels and host splicing patterns were influenced most strongly by tissue differences, followed by the effect of inflammation. Both factors point towards a substantial disease-related alteration of metabolic processes. We also observed a strong enrichment of splicing events in inflamed tissues, accompanied by an alteration of the mucosa-attached bacterial taxa. Finally, we noted a striking uncoupling of the three molecular entities when moving from healthy individuals via disease controls to patients with IBD.

CONCLUSIONS

Our results provide strong evidence that the interplay between microbiome and host transcriptome, which normally characterises a state of intestinal homeostasis, is drastically perturbed in Crohn's disease and UC. Consequently, integrating multiple OMICs levels appears to be a promising approach to further disentangle the complexity of IBD.

Anti-NKG2D monoclonal antibody (NNC0142-0002) in active Crohn's disease: a randomised controlled trial

OBJECTIVE

Anti-NKG2D (NNC0142-0002) is an antagonising human immunoglobulin G4 monoclonal antibody that binds to natural killer group 2 member D (NKG2D) receptors, which are expressed by T cells and innate lymphoid cells, and may be linked to mucosal damage in Crohn's disease (CD).

DESIGN

Seventy-eight patients (aged ≥18 and ≤75 years) with CD for ≥3 months, Crohn's Disease Activity Index (CDAI) ≥220 and ≤450 and either C-reactive protein ≥10 mg/L or endoscopic evidence of inflammation, were randomised 1:1 to a single subcutaneous (SC) dose of 2 mg/kg anti-NKG2D or placebo. Primary endpoint was change in CDAI (ΔCDAI) from baseline to week 4. Prespecified significance level was 10% for CDAI endpoints. A futility analysis was instituted due to slow recruitment.

RESULTS

Primary endpoint was not significantly different between anti-NKG2D and placebo (week 4 ΔCDAI=-16); however, there was a significant difference by week 12 (ΔCDAI=-55; p≤0.10). Significant improvements were noted in the non-failure to biologics subgroup (treated with anti-NKG2D (n=28)) from week 1 onward. Greater effects of anti-NKG2D were also observed in patients with baseline CDAI ≥330. Frequencies of adverse events (AEs) were comparable between anti-NKG2D and placebo. Most AEs were mild (49%) or moderate (43%). No antidrug antibodies were observed.

CONCLUSIONS

A single SC dose of 2 mg/kg anti-NKG2D did not reduce disease activity at week 4 versus placebo, but the difference was significant at week 12, and effects were evident in key subgroups. These data support further development of anti-NKG2D in IBD.

TRIAL REGISTRATION NUMBER

NCT01203631.

Assays for measurement of TNF antagonists in practice

Tumour necrosis factor (TNF) antagonist drug exposure is correlated with clinical, endoscopic and pathophysiological outcomes during induction and maintenance therapy. Measuring drug concentrations is therefore a useful tool when treating to target and optimising therapy. One of the main factors leading to suboptimal drug exposure is the formation of antidrug antibodies (ADAs), due to an immunogenic reaction of the immune system towards the non-self protein. The development of ADA does pose important concerns for drug efficacy and for safety as ADAs have been associated with acute infusion reactions, hypersensitivity reactions and serum sickness. Various assays exist to measure serum drug and ADA concentrations, either offered as a service in a specialised laboratory or commercially available as a kit. It is unclear how the performance of these assays relates to each other, until recently various comparative studies were carried out. The majority of these studies show that indeed a good correlation exists between the assays that measure drug, but that absolute concentrations can differ across tests. This is particularly relevant in clinical practice when a specific threshold or drug concentration range is targeted. For ADA assays, drug sensitivity or the ability of the assay to measure ADA in the presence of drug remains an important issue, especially for drugs with a higher dosing frequency. In addition, standardisation across ADA assays is difficult, making it hard to compare quantitative or semiquantitative (low/medium/high) results across assays and across studies.

Implementing a self-management strategy in inflammatory bowel disease (IBD): patient perceptions, clinical outcomes and the impact on service

INTRODUCTION

Patient self-management and its service integration is not a new concept but it may be a key component in the long-term sustainability of inflammatory bowel disease (IBD) service provision, when considering growing disease prevalence and limited resources.

METHODS

The IBD team at the Royal Alexandra and Vale of Leven Hospitals in the Clyde Valley region developed a self-management tool, called the 'flare card'. Patients were asked to complete a questionnaire which reflected their opinion on its viability as a self-management intervention. In addition, its utility in terms of service use over a 10-month period in 2016 was compared with a similar cohort of patients over 10 months in 2015.

RESULTS

Patients overall felt that the 'flare card' was a viable self-management tool. Positive feedback identified that the intervention could help them aid control over their IBD, improve medication adherence, reduce symptoms and reflected a feeling of patient-centred IBD care. The comparison between 2015 and 2016 service use revealed a significant reduction in IBD and non-IBD service usage, Steroid prescribing and unscheduled IBD care in the flare card supported cohort.

CONCLUSIONS

IBD services must continue to adapt to changes within the National Health Service bearing in mind long-term sustainability and continued care provision. The 'flare card' goes further in an attempt to optimise Crohn's disease and ulcerative colitis management by harmonising clinician evaluation and patient's self-initiation of therapy and investigation.

Proteomic analysis of ascending colon biopsies from a paediatric inflammatory bowel disease inception cohort identifies protein biomarkers that differentiate Crohn's disease from UC

OBJECTIVE

Accurate differentiation between Crohn's disease (CD) and UC is important to ensure early and appropriate therapeutic intervention. We sought to identify proteins that enable differentiation between CD and UC in children with new onset IBD.

DESIGN

Mucosal biopsies were obtained from children undergoing baseline diagnostic endoscopy prior to therapeutic interventions. Using a super-stable isotope labeling with amino acids in cell culture (SILAC)-based approach, the proteomes of 99 paediatric control and biopsies of patients with CD and UC were compared. Multivariate analysis of a subset of these (n=50) was applied to identify novel biomarkers, which were validated in a second subset (n=49).

RESULTS

In the discovery cohort, a panel of five proteins was sufficient to distinguish control from IBD-affected tissue biopsies with an AUC of 1.0 (95% CI 0.99 to 1.0); a second panel of 12 proteins segregated inflamed CD from UC within an AUC of 0.95 (95% CI 0.86 to 1.0). Application of the two panels to the validation cohort resulted in accurate classification of 95.9% (IBD from control) and 80% (CD from UC) of patients. 116 proteins were identified to have correlation with the severity of disease, four of which were components of the two panels, including visfatin and metallothionein-2.

CONCLUSIONS

This study has identified two panels of candidate biomarkers for the diagnosis of IBD and the differentiation of IBD subtypes to guide appropriate therapeutic interventions in paediatric patients.

Comparative genomics of Crohn's disease-associated adherent-invasive Escherichia coli

OBJECTIVE

Adherent-invasive Escherichia coli (AIEC) are a leading candidate bacterial trigger for Crohn's disease (CD). The AIEC pathovar is defined by in vitro cell-line assays examining specific bacteria/cell interactions. No molecular marker exists for their identification. Our aim was to identify a molecular property common to the AIEC phenotype.

DESIGN

41 B2 phylogroup E. coli strains were isolated from 36 Australian subjects: 19 patients with IBD and 17 without. Adherence/invasion assays were conducted using the I-407 epithelial cell line and survival/replication assays using the THP-1 macrophage cell line. Cytokine secretion tumour necrosis factor ((TNF)-α, interleukin (IL) 6, IL-8 and IL-10) was measured using ELISA. The genomes were assembled and annotated, and cluster analysis performed using CD-HIT. The resulting matrices were analysed to identify genes unique/more frequent in AIEC strains compared with non-AIEC strains. Base composition differences and clustered regularly interspaced palindromic repeat (CRISPR) analyses were conducted.

RESULTS

Of all B2 phylogroup strains assessed, 79% could survive and replicate in macrophages. Among them, 11/41 strains (5 CD, 2 UCs, 5 non-IBD) also adhere to and invade epithelial cells, a phenotype assigning them to the AIEC pathovar. The AIEC strains were phylogenetically heterogeneous. We did not identify a gene (or nucleic acid base composition differences) common to all, or the majority of, AIEC. Cytokine secretion and CRISPRs were not associated with the AIEC phenotype.

CONCLUSIONS

Comparative genomic analysis of AIEC and non-AIEC strains did not identify a molecular property exclusive to the AIEC phenotype. We recommend a broader approach to the identification of the bacteria-host interactions that are important in the pathogenesis of Crohn's disease.