Does weight-adjusted anti-tumour necrosis factor treatment favour obese patients with Crohn's disease?

Impact of Obesity and Metabolic Syndrome on IBD Outcomes

PURPOSE OF REVIEW

The recent surge in inflammatory bowel disease (IBD) cases has paralleled a significant rise in obesity and metabolic comorbidities rates. In this article, we explore the potential influence of obesity and associated metabolic comorbidities on disease progression, complications, treatment response, surgical outcomes, health economics, and the potential impact of obesity treatment on the course of IBD.

FINDINGS

Contrary to visceral adiposity, obesity does not consistently result in an increased risk of IBD-related complications. Patients with IBD have a higher risk of acute arterial events, likely linked to systemic inflammation. Substantial evidence suggests that obesity has a negative impact on the response to IBD treatment, with this effect being most thoroughly studied in biologics and immunomodulators. The rates of overall complications and post-operative infections are higher in patients who are obese. There are limited but promising data regarding the impact of weight loss techniques, including exercise, medications, and bariatric interventions, on the outcomes in IBD. Both obesity and diabetes have adverse effects on the overall quality of life and place an increased financial burden on the IBD population. A growing body of evidence indicates a connection between obesity and associated metabolic comorbidities and negative outcomes in IBD, yet further efforts are required to fully understand this relationship.

Reviewing the impact of obesity on inflammatory bowel disease and considerations for optimizing management

PURPOSE OF REVIEW

This review examines the complex relationship between obesity and inflammatory bowel disease (IBD), encompassing their potentially shared pathogenesis, the impact of obesity on the natural history and treatment outcomes of IBD, and the management of obesity in the patient with IBD.

RECENT FINDINGS

Obesity represents a state of chronic inflammation that may not only contribute to IBD pathogenesis, but also influence disease progression, complications, and response to treatment. Increased visceral adiposity may carry negative prognostic implications for disease and treatment-specific outcomes. Antiobesity medications, endoscopic bariatric therapies, and even bariatric surgery may be effective and well tolerated in selected patients with IBD.

SUMMARY

The intersection of obesity and IBD presents a significant clinical challenge, with obesity influencing the natural history of IBD and potentially affecting treatment efficacy. As obesity prevalence among IBD patients rises, a tailored approach to management is crucial, taking into account the individualized risks and benefits of various treatment strategies, including lifestyle interventions, pharmacotherapy, endoscopic procedures, and bariatric surgery.

High Body Mass Index and Response to Anti-Tumor Necrosis Factor Therapy in Pediatric Crohn's Disease

INTRODUCTION

Obesity is common among patients with pediatric Crohn's disease (PCD). Some adult studies suggest obese patients respond less well to anti-tumor necrosis factor (TNF) treatment. This study sought compares anti-TNF response and anti-TNF levels between pediatric patients with normal and high body mass index (BMI).

METHODS

The COMBINE trial compared anti-TNF monotherapy with combination therapy with methotrexate in patients with PCD. In this secondary analysis, a comparison of time-to-treatment failure among patients with normal BMI vs BMI Z -score >1, adjusting for prescribed anti-TNF (infliximab [IFX] or adalimumab [ADA]), trial treatment assignment (combination vs monotherapy), and relevant covariates. Median anti-TNF levels across BMI category was also examined.

RESULTS

Of 224 participants (162 IFX initiators and 62 ADA initiators), 111 (81%) had a normal BMI and 43 (19%) had a high BMI. High BMI was associated with treatment failure among ADA initiators (7/10 [70%] vs 12/52 [23%], hazard ratio 0.29, P = 0.007) but not IFX initiators. In addition, ADA-treated patients with a high BMI had lower ADA levels compared with those with normal BMI (median 5.8 vs 12.8 μg/mL, P = 0.02). IFX trough levels did not differ between BMI groups.

DISCUSSION

Overweight and obese patients with PCD are more likely to experience ADA treatment failure than those with normal BMI. Higher BMI was associated with lower drug trough levels. Standard ADA dosing may be insufficient for overweight children with PCD. Among IFX initiators, there was no observed difference in clinical outcomes or drug levels, perhaps due to weight-based dosing and/or greater use of proactive drug monitoring.

The Impact of Obesity on Inflammatory Bowel Disease

Obesity is prevalent in the inflammatory bowel disease (IBD) population, particularly in newly developed countries where both IBD and obesity in the general population are on the rise. The role of obesity in the pathogenesis of IBD was entertained but results from available studies are conflicting. It does, however, appear to negatively influence disease course whilst impacting on our medical and surgical therapies. The pro-inflammatory profile of the visceral adipose tissue might play a role in the pathogenesis and course of Crohn's Disease (CD). Interestingly, isolating the mesentery from the surgical anastomosis using a KONO-S technique significantly decreases anastomotic recurrence rate. Anti-obesity therapy is not widely used in IBD but was suggested as an adjunctive therapy in those patients. In this review, we aimed to highlight the epidemiology of obesity in IBD and to describe its influence on disease course and outcomes.

Nutrition, Nutritional Status, Micronutrients Deficiency, and Disease Course of Inflammatory Bowel Disease

During the disease course, most Inflammatory Bowel Disease patients present a condition of malnutrition, undernutrition, or even overnutrition. These conditions are mainly due to suboptimal nutritional intake, alterations in nutrient requirements and metabolism, malabsorption, and excessive gastrointestinal losses. A suboptimal nutritional status and low micronutrient serum levels can have a negative impact on both induction and maintenance of remission and on the quality of life of Inflammatory Bowel Disease patients. We performed a systematic review including all the studies evaluating the connection between nutrition, nutrition status (including undernutrition and overnutrition), micronutrient deficiency, and both disease course and therapeutic response in Inflammatory Bowel Disease patients. This systematic review was performed using PubMed/MEDLINE and Scopus. Four main clinical settings concerning the effect of nutrition on disease course in adult Inflammatory Bowel Disease patients were analyzed (induction of remission, maintenance of remission, risk of surgery, post-operative recurrence, and surgery-related complications). Four authors independently reviewed abstracts and manuscripts for eligibility. 6077 articles were found; 762 duplicated studies were removed. Out of 412 full texts analyzed, 227 were included in the review. The evidence summarized in this review showed that many nutritional aspects could be potential targets to induce a better control of symptoms, a deeper remission, and overall improve the quality of life of Inflammatory Bowel Disease patients.

The importance of predicting patient responses to monoclonal antibodies for Crohn's disease

INTRODUCTION

Crohn's disease (CD) is a chronic immune-mediated inflammatory bowel disease that results in relapsing and remitting symptoms but progressive transmural bowel damage leading to significant morbidity. CD results from dysregulation of the immune system related to genetic and environmental factors. While the use of monoclonal antibodies targeting cytokines and adhesion molecules has been shown to improve outcomes in CD patients, their widespread use has been limited due to high costs as well as variable access. Here, we summarize the factors that have been shown to correlate with responsiveness to biologic agents for use in practice.

AREAS COVERED

We summarize the current literature regarding factors that have been shown to influence patient response to various biologic agents including: patient-related factors (e.g. age, gender, weight smoking history); disease-specific factors (e.g. disease duration, location/extension, behavior/phenotype, severity); genetic markers; transcription factors, and the gut microbiome. Finally, we review the utility of prediction models and present data supporting the use of recently developed decision support tools.

EXPERT OPINION

Clinical decision support tools developed by machine learning are currently available for the selection of biologic agents in CD patients. We expect these models to become an integral tool for clinicians in the treatment of CD in the coming years.

Dose Escalation Patterns of Advanced Therapies in Crohn's Disease and Ulcerative Colitis: A Systematic Literature Review

INTRODUCTION

Dose escalation is one of the treatment approaches studied and suggested in advanced therapies for Crohn's disease (CD) and ulcerative colitis (UC). This study aimed to identify and characterize the dosing escalation patterns of advanced therapies in CD and UC.

METHODS

Two systematic literature reviews (SLRs) were conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE®, Embase®, and Cochrane Library were searched for articles published between January 2011 and October 2021 and limited to non-interventional studies in English language. Congress and bibliographic searches were also conducted. Articles were screened by two independent researchers. Dose escalation patterns were described and summarized considering the regional regulatory label recommendation (in North America [NA] or outside of North America [ONA]).

RESULTS

Among 3190 CD and 2116 UC articles identified in the Ovid searches, 100 CD and 54 UC studies were included in the SLR, with more studies conducted ONA. Most studies reported an initial maintenance dose pattern aligned with the lower starting dose per local regulatory label; however, several ONA studies (n = 13 out of 14) reported ustekinumab every 8 weeks as starting maintenance pattern in CD. In ONA studies, the median within-guideline escalation rates in CD and UC were 43% in ustekinumab (CD only), 33% and 32% for vedolizumab; 29% and 39% for adalimumab; and 14% and 10% for infliximab. Evidence regarding dose escalation patterns for tofacitinib, certolizumab pegol, and golimumab was limited. Some dose escalation patterns outside of label recommendations were observed including ustekinumab every 8 weeks to every 4 weeks and vedolizumab every 8 weeks to every 6 weeks.

CONCLUSION

Dose escalation strategies are widely documented in the literature. The reported dose escalation patterns and escalation rates vary by region and by CD and UC. Most escalation patterns reported were aligned with regulatory recommendations while some reported more diverse or aggressive dose escalation.

PROSPERO REGISTRATION

CRD42021289251.

Practical guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean gastrointestinal patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The present practical guideline is intended for clinicians and practitioners in general medicine, gastroenterology, surgery and other obesity management, including dietitians and focuses on obesity care in patients with chronic gastrointestinal diseases.

METHODS

The present practical guideline is the shortened version of a previously published scientific guideline developed according to the standard operating procedure for ESPEN guidelines. The content has been re-structured and transformed into flow-charts that allow a quick navigation through the text.

RESULTS

In 100 recommendations (3× A, 33× B, 24 × 0, 40× GPP, all with a consensus grade of 90% or more) care of gastrointestinal patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially metabolic associated liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present practical guideline offers in a condensed way evidence-based advice how to care for patients with chronic gastrointestinal diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint European Society for Clinical Nutrition and Metabolism / United European Gastroenterology guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for European Society for Clinical Nutrition and Metabolism guidelines, following the Scottish Intercollegiate Guidelines Network grading system (A, B, 0, and good practice point [GPP]). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

A Comparative Analysis of Drug Therapy, Disease Phenotype, and Health Care Outcomes for Men and Women with Inflammatory Bowel Disease

BACKGROUND

Sex and gender refer to biological and social differences between men and women. While well-evaluated in other disciplines, their roles in inflammatory bowel disease (IBD) are not well-defined. This study aimed to characterize differences in healthcare outcomes in men and women with IBD.

METHODS

A retrospective single-centre cohort study was conducted to evaluate differences between men and women receiving care for Crohn's disease (CD) and ulcerative colitis (UC) at the Western University Personalized Medicine Clinic from March 2012 to September 2019. The primary endpoint was the proportion of IBD drugs used for all drug classes. Additional outcomes in healthcare utilization and disease phenotype were assessed. Student's t test and Fisher's exact test were used to assess differences RESULTS: A total of 1015 participants were included (CD = 656; UC = 359). In UC and CD, 47.9% and 59.0% were women, respectively. Overall, women were more likely prescribed budesonide than men (23.6% vs. 13.4%; p < 0.0001), while more men were exposed to prednisone for IBD management (73.5% vs. 67.4%; p = 0.04). Immunomodulator use was higher in men with CD versus women (86.6% vs. 78.3%; p = 0.008) and of those exposed, women more commonly experienced ADRs (29.5% vs. 21.2%; p = 0.01). Though no sex-related difference was identified, age was a predictor of biologic exposure in women with CD and men with UC, with those > 55 being less likely to receive biologics.

CONCLUSIONS

These findings highlight differences in disease course and treatment approaches between men and women with IBD and support the consideration of sex and gender when researching disease outcomes.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for ESPEN guidelines, following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (A, B, 0, and good practice point (GPP)). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

High-fat diet aggravates colitis via mesenteric adipose tissue derived exosome metastasis-associated lung adenocarcinoma transcript 1

BACKGROUND

Obesity is associated with an increased risk of developing Crohn’s disease (CD), higher disease activity, and comparatively worse clinical outcomes.

AIM

To investigate the role of mesenteric adipose tissue-derived exosomes in the pathogenesis of CD aggravation in obese individuals.

METHODS

First, we induced colitis in mice initiated on high-fat and normal diets and compared the severity of colitis. We then extracted and identified exosomes from mesenteric adipose tissue and determined the levels of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in mesenteric adipose tissue-derived exosomes and the colon. Next, we demonstrated an interaction between MALAT1 and the miR-15a-5p/activating transcription factor 6 (ATF6) axis. Finally, we explored the effects of mesenteric adipose tissue-derived exosomes extracted from mice fed a high-fat or normal diet on the severity of 2,4,6-trinitrobe-nzenesulfonic acid (TNBS)-induced colitis and ATF6-related endoplasmic reticulum stress pathways.

RESULTS

High-fat diet was found to aggravate TNBS-induced colitis in mice. The expression of MALAT1 in mesenteric adipose tissue-derived exosomes of high-fat diet-fed mice increased. The increased expression of MALAT1 in colon tissue exacerbated TNBS-induced colitis and activated the ATF6 endoplasmic reticulum stress pathway. This effect was partially reversed by the reduced expression of MALAT1 and overexpression of miR-15a-5p.

CONCLUSION

Mesenteric adipose tissue-derived exosome-encapsulated long noncoding RNAs MALAT1 targets the colon and aggravates TNBS-induced colitis in obese mice, which may potentially act on the miR-15a-5p/ATF6 axis and activate endoplasmic reticulum stress.

BMI is important in predicting the loss of response in inflammatory bowel disease patients on tumour necrosis factor-α inhibitors

INTRODUCTION

Obesity is an emerging phenomenon among patients with inflammatory bowel disease (IBD). This study aims to evaluate whether the response to tumour necrosis factor-α (TNF-α) inhibitors (infliximab and adalimumab) could be influenced by BMI in IBD.

METHODS

We identified a cohort of 181 IBD patients attending a single-tertiary centre, naive to biologic therapy and stratified them according to their BMI. The primary outcome is the first occurrence of loss of response (LOR).

RESULTS

The median BMI was 26 kg/m2 (15-63 kg/m2). Approximately 68% of patients had LOR on both adalimumab (ADA) (n = 52) and infliximab (IFX) (n = 71). However, 83% on ADA with BMI ≥30 kg/m2 had LOR compared to 61% on IFX with BMI ≥30 kg/m2. For patients on ADA, Cox regression analysis revealed that after accounting for age, sex, disease type, duration of disease, fistulising disease, smoking status, haemoglobin, C-reactive protein, albumin and platelet levels, there were statistically significant associations between BMI (≥30 kg/m2 vs. <30 kg/m2) and LOR [P = 0.010; hazard ratio (HR) 3.2; confidence interval (CI), 1.3-7.6]. However, for patients on IFX, after accounting for the same factors, the only significant factor was the association of lower rate of LOR with higher albumin levels (P = 0.024; HR 0.95; CI, 0.91-0.99). There was an increased accelerated time to LOR for patients on ADA with BMI ≥30 kg/m2 compared to BMI <30 kg/m2 (P = 0.026). However, there was no difference in time to LOR for patients on IFX (P = 0.177).

CONCLUSION

BMI is important in predicting the LOR among IBD patients on TNF-α inhibitors, especially among patients receiving ADA.

Impact of Obesity on Response to Biologic Therapies in Patients with Inflammatory Bowel Diseases

Approximately 20-40% of patients with inflammatory bowel disease (IBD) are obese. Obesity is associated with inferior outcomes in patients with IBD, with lower rates of achieving remission, poor quality of life, and higher burden of unplanned healthcare utilization. Multiple cohort studies in patients with immune-mediated inflammatory diseases, including IBD, treated with biologic agents like tumor necrosis factor-α antagonists have suggested that obesity is associated with inferior response to biologic therapy. This may be related to the negative impact of obesity on the pharmacokinetics of biologic agents. Pharmacokinetic studies of multiple biologic agents have demonstrated that high body weight is associated with more rapid clearance and a higher volume of distribution of biologic agents, which leads to low trough concentrations. Randomized trials in patients with psoriasis and psoriatic arthritis treated with biologic agents suggest that diet- or lifestyle-induced weight loss is associated with improved response to therapy. This provides an opportunity to explore intentional weight loss as adjunctive therapy in obese patients with IBD. However, diet and lifestyle interventions for weight loss are hard to implement in patients with IBD; hence, long-term therapy with weight-loss agents (such as with phentermine-topiramate, naltrexone-bupropion) is attractive as adjunctive therapy in obese patients with IBD.

Impact of Obesity on Inflammatory Bowel Disease

PURPOSE OF REVIEW

This review highlights recent work that evaluates the impact of obesity on inflammatory bowel disease (IBD) pathogenesis and management.

RECENT FINDINGS

The impact of obesity on IBD prevalence, clinical course, and management, has been studied and described more so in recent years. Studies have shown that obesity increases IBD disease activity, leads to longer hospitalization courses, and increases the likelihood of the development of extraintestinal manifestations. Recent evidence has also suggested that obese IBD patients have a higher frequency of extended steroid treatment and increased use of antibiotics compared to non-obese IBD patients. The effect of obesity on patients with IBD is a topic that has garnered widespread interest in the last decade due to the increasing prevalence of both diseases. To date however, although there are still many unanswered questions. It is quite clear that obesity, and more specifically, visceral adiposity, affects numerous IBD-related outcomes in regard to pathogenesis, extra-intestinal manifestations, response to medical and surgical therapies, hospital length of stay, healthcare-related costs, and health-related quality of life. Future studies should include larger patient populations and evaluate additional factors that are altered in those with obesity including the gut microbiome, dietary patterns, and whether weight loss and/or degree of weight loss impact clinical outcomes.

Optimizing biologic therapy in inflammatory bowel disease: a Delphi consensus in the United Arab Emirates

BACKGROUND

Inflammatory bowel diseases (IBD) are chronic, relapsing-remitting inflammatory conditions with a substantial negative impact on health-related quality of life and work productivity. Treatment of IBD has been revolutionized by the advent of biologic therapies, initially with anti-TNF agents and more recently with multiple alternatives targets, and yet more under development.

OBJECTIVES

Approximatively one third of patients do not respond to biologic therapy and more importantly a significant proportion experiences partial response or loss of response during treatment. The latter are common clinical situations and paradoxically are not addressed in the commercial drug labels and available guidelines. There is therefore a clinical need for physicians to understand when and how eventually to optimize the biologic therapy.

DESIGN

This consensus using a Delphi methodology was promoted and supported by the Emirates Society of Gastroenterology and Hepatology to close this gap.

DATA SOURCES AND METHODS

Following an extensive systematic review of over 60,000 studies, 81 studies with dose escalation and five addressing drug monitoring were selected and in addition five systematic reviews and three guidelines.

RESULTS AND CONCLUSION

after three rounds of voting 18 statements were selected with agreement ranging from of 80% to 100.

Adalimumab Concentration Changes After Dose Escalation in Inflammatory Bowel Disease

BACKGROUND

Dose escalation of adalimumab (ADA) for loss or response in inflammatory bowel disease (IBD) is a common practice. Recent data suggest improved outcomes with an ADA concentration of 12 mcg/mL, but limited data are available on the ability to achieve a target concentration. The aim of this study was to determine the expected change in serum ADA concentration after a dose escalation performed every 7 days in patients with IBD.

METHODS

A retrospective cohort of patients with IBD receiving ADA was divided into every fourteen-day dosing, every 7-day dosing, and dose escalation (ie, q14 to q7 day dosing). The primary outcome was the change in ADA concentration. Multiple logistic regression was performed to identify predictors of achieving a target ADA concentration of ≥12 mcg/mL.

RESULTS

Overall, 380 patients were identified, of whom 200 underwent dose escalation, 100 remained on q14 days dosing, and 80 were maintained on q7 day dosing. After dose escalation, the mean ADA concentration increased by 5.5 mcg/mL (P < 0.0001). After dose escalation, a significant proportion of patients achieved an ADA concentration ≥12 mcg/mL (P = 0.0019), as well as clinical remission (P = 0.0053). Based on multiple logistic regression, age of <46 years [odds ratio (OR): 2.4; 95% confidence interval (CI): 1.3, 4.6; P < 0.01], body mass index of <29 (OR: 0.21; 95% CI: 0.1, 0.5; P < 0.0001), and initial ADA concentration of ≥3.0 mcg/mL were found to be associated with a target ADA concentration ≥12 mcg/mL (OR: 4.76; 95% CI: 2.3, 9.7; P < 0.0001).

CONCLUSIONS

The average expected increase in serum ADA concentration after dose escalation from q14 to q7 days was 5.5 mcg/mL. The initial ADA concentration, age, and body mass index may influence the ability to achieve a target ADA concentration after dose escalation.

Obesity in inflammatory bowel disease: A review of its role in the pathogenesis, natural history, and treatment of IBD

In contrast to previous perceptions that inflammatory bowel disease (IBD) patients are generally malnourished and underweight, there is mounting evidence to suggest that rates of obesity in IBD now mirror that of the general population. IBD is an immune-mediated condition that appears to develop in individuals who have not only a genetic predisposition to immune dysregulation but also likely exposure to various environmental factors which further potentiate this risk. With the surge in obesity alongside the rising incidence of IBD, particularly in developing nations, the role that obesity may play, not only in the pathogenesis but also in the natural history of disease has become a topic of growing interest. Currently available data exploring obesity's impact on the natural history of IBD are largely conflicting, potentially limited by the use of body mass index as a surrogate measure of obesity at varying time points throughout the disease course. While there are pharmacokinetic data to suggest possible detrimental effects that obesity may have on the response to medical therapy, results in this realm are also inconsistent. Moreover, not only is it unclear whether weight loss improves IBD outcomes, little is known about the safety and efficacy of available weight-loss strategies in this population. For these reasons, it becomes increasingly important to further understand the nature of any interaction between obesity and IBD.

Frequency and Effectiveness of Empirical Anti-TNF Dose Intensification in Inflammatory Bowel Disease: Systematic Review with Meta-Analysis

Loss of response to antitumor necrosis factor (anti-TNF) therapies in inflammatory bowel disease occurs in a high proportion of patients. Our aim was to evaluate the loss of response to anti-TNF therapy, considered as the need for dose intensification (DI), DI effectiveness and the possible variables influencing its requirements. Bibliographical searches were performed.

SELECTION

prospective and retrospective studies assessing DI in Crohn's disease and ulcerative colitis patients treated for at least 12 weeks with an anti-TNF drug.

EXCLUSION CRITERIA

studies using anti-TNF as a prophylaxis for the postoperative recurrence in Crohn's disease or those where DI was based on therapeutic drug monitoring.

DATA SYNTHESIS

effectiveness by intention-to-treat (random effects model). Data were stratified by medical condition (ulcerative colitis vs. Crohn's disease), anti-TNF drug and follow-up.

RESULTS

One hundred and seventy-three studies (33,241 patients) were included. Overall rate of the DI requirement after 12 months was 28% (95% CI 24-32, I2 = 96%, 41 studies) in naïve patients and 39% (95% CI 31-47, I2 = 86%, 18 studies) in non-naïve patients. The DI requirement rate was higher both in those with prior anti-TNF exposure (p = 0.01) and with ulcerative colitis (p = 0.02). The DI requirement rate in naïve patients after 36 months was 35% (95% CI 28-43%; I2 = 98%; 18 studies). The overall short-term response and remission rates of empirical DI in naïve patients were 63% (95% CI 48-78%; I2 = 99%; 32 studies) and 48% (95% CI: 39-58%; I2 = 92%; 25 studies), respectively. The loss of response to anti-TNF agents-and, consequently, DI-occurred frequently in inflammatory bowel disease (approximately in one-fourth at one year and in one-third at 3 years). Empirical DI was a relatively effective therapeutic option.

Body mass index and treatment survival in patients with RA starting treatment with TNFα-inhibitors: long-term follow-up in the real-life METEOR registry

Objectives

To study whether there is an association between body mass index (BMI) category and survival of various tumour necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA) patients in a real-life longitudinal international registry.

Methods

Data from 5230 patients with RA starting treatment with any TNFi were selected from the METEOR registry. Patients were divided into six BMI categories: 3.7% underweight, BMI<18.5 kg/m²; 46% normal weight, BMI 18.5–25 kg/m²; 32% pre-obesity, BMI 25–30 kg/m²; 13% obesity class I, BMI 30–35 kg/m²; 3.4% obesity class II, BMI 35–40 kg/m²; and 1.6% obesity class III, BMI >40 kg/m². Time on treatment in the different BMI categories was compared for all TNFi combined and for the infliximab, adalimumab and etanercept separately, using Kaplan–Meier curves and Cox regression analyses. Cox regression analyses were adjusted for potential confounders, with follow-up censored at 5000 days.

Results

Patients in obesity class II (HR 1.28, 95% CI 1.06 to 1.54) and III (HR 1.67, 95% CI 1.29 to 2.18) and underweight patients (HR 1.30, 95% CI 1.07 to 1.58) showed statistically significantly shorter TNFi survival than normal weight patients. The effect in underweight patients was strongest for infliximab (HR 1.82, 95% CI 1.20 to 2.76), the effect in overweight patients was strongest for infliximab (category II (HR 1.49, 95% CI 0.98 to 2.26); category III (HR 1.46, 95% CI 0.79 to 2.71)) and etanercept (category II (HR 1.27 95% CI 0.98 to 1.65); category III (HR 1.79, 95% CI 1.25 to 2.55)). No significant effect modification from reported pain was found.

Conclusion

Both underweight and overweight patients discontinued TNFi treatment earlier than normal weight patients, without evidence of reported pain as the main determinant. It remains uncertain what determines TNFi survival in individual patients.

Associations Between Obesity and the Effectiveness of Anti–Tumor Necrosis Factor-α Agents in Inflammatory Bowel Disease Patients: A Literature Review and Meta-analysis

Background: A total of 15% to 40% of adult inflammatory bowel disease (IBD) patients are obese. The influence of obesity on anti-tumor necrosis factor-α (anti-TNF-α) treatment in IBD patients is not consistent. Objective: To determine the association between obesity and the efficacy of anti-TNF treatment in IBD patients. Methods: We performed a systematic search from January 1990 through November 2019 on MEDLINE, Web of Science, Google Scholar, ClinicalTrials.gov, and Cochrane library. We included randomized controlled trials and observational cohort studies that investigated the outcome of anti-TNF treatment in IBD patients with stratification according to body mass index or body weight. The odds ratio (OR) and its 95% CI were calculated. Results: In this pooled meta-analysis, we observed that obesity increased the odds of failure of anti-TNF therapy (OR = 1.195; 95% CI = 1.034-1.380; P = 0.015; I2 = 47.8%). After performing subgroup analyses, obesity was associated with higher odds of anti-TNF treatment failure in ulcerative colitis (UC) patients (OR = 1.413; 95% CI = 1.008-1.980; P = 0.045; I2 = 20.0%) but not in Crohn’s disease patients (OR = 1.099; 95% CI = 0.928-1.300). Obesity significantly increased the odds of treatment failure of both dose-fixed and weight-based anti-TNF agents (OR = 1.121, 95% CI = 1.027-1.224, P = 0.011, and OR = 1.449, 95% CI = 1.006-2.087, P = 0.046, respectively). Conclusion and Relevance: In our meta-analysis, obesity was associated with the inferior response of anti-TNF treatments in UC patients. Clinicians should be aware that obese UC patients may require higher doses in anti-TNF treatment.

Comparison of Real-World Outcomes of Infliximab versus Adalimumab in Biologic-Naïve Korean Patients with Ulcerative Colitis: A Population-Based Study

PURPOSE

Data on the comparative effectiveness of infliximab (IFX) or adalimumab (ADA) in patients with ulcerative colitis (UC) are extremely limited, especially in the Asian population. We compared clinically important outcomes [colectomy, UC-related emergency room (ER) visits, UC-related hospitalizations, and need for corticosteroids] for these two biologics in biologic-naïve Korean patients with UC.

MATERIALS AND METHODS

Using National Health Insurance claims, we collected data on patients who were diagnosed with UC and exposed to IFX or ADA between 2010 and 2016.

RESULTS

A total of 862 new users of biologics were included, of whom 630 were treated with IFX and 232 were treated with ADA. Over a median follow-up of 1.8 years after starting biologic therapy, there were no significant differences in the risk of colectomy [adjusted hazard ratio (aHR), 1.87; 95% confidence interval (CI), 0.30-11.63], ER visits (aHR, 1.58; 95% CI, 0.79-3.16), hospitalizations (aHR, 0.83; 95% CI, 0.59-1.17), and corticosteroid use (aHR, 1.16; 95% CI, 0.76-1.78) between IFX and ADA users. These results were stable even when only patients who used biologics for ≥6 months were analyzed. Additionally, these results were unchanged in patients treated with biologic monotherapy or combination therapy with immunomodulators.

CONCLUSION

In this nationwide population-based study, there was no significant difference in the risk of colectomy, ER visits, hospitalizations, and corticosteroid use between IFX and ADA users. Our findings indicate that IFX and ADA have comparable effectiveness in biologic-naïve Korean patients with UC.

High body mass index is not associated with increased treatment failure in infliximab treated pediatric patients with inflammatory bowel disease

Background and Aim

While weight gain during infliximab therapy in inflammatory bowel disease (IBD) is common, there has been limited research evaluating its impact on infliximab efficacy.

Methods

Primary aims of this study were to determine the frequency of excess weight gain (body mass index [BMI] > 25 kg/m²) in children with IBD on maintenance infliximab and evaluate the impact on infliximab dosing, serum trough levels, and treatment failure. Secondary aims were to determine differences in weight gain, treatment characteristics, and clinical/biochemical variables between patients with therapeutic and subtherapeutic maintenance therapy trough levels. We performed a retrospective study of 253 pediatric IBD (75.1% Crohn's disease, 23.3% ulcerative colitis, 1.6% IBD-unclassified) patients on infliximab followed at BC Children's Hospital between January 2013 and January 2018.

Results

Median age at infliximab initiation was 13.9 years, median length of follow up was 56.9 months, and 55.7% were males; 10.3% of the cohort demonstrated excess weight gain (7.5% overweight, 2.8% obese). Average mg/kg dosing was not statistically different between groups (normal, overweight, and obese: 6.7, 6.4, and 6.7 mg/kg, respectively, P = 0.52). Median BMI of patients with therapeutic and subtherapeutic trough levels was similar at 19.9 kg/m² (interquartile range [IQR], 17.3-23.8) and 19.7 kg/m² (IQR, 17.4-21.9), respectively. BMI had no effect on secondary loss of response to infliximab, with no significant difference between normal and high BMI subgroups (13.4 vs. 16.7%, P = 0.9).

Conclusions

In a subgroup of pediatric IBD patients on maintenance infliximab, excess weight gain was not associated with higher weight-based dosing, lower serum trough levels, or increased risk of treatment failure.

The Effect of Initiation of Anti-TNF Therapy on the Subsequent Direct Health Care Costs of Inflammatory Bowel Disease

BACKGROUND

Anti-tumor necrosis factor (anti-TNF) drugs are highly effective in the treatment of moderate-to-severe Crohn's disease (CD) and ulcerative colitis (UC), but they are very costly. Due to their effectiveness, they could potentially reduce future health care spending on other medical therapies, hospitalization, and surgery. The impact of downstream costs has not previously been quantified in a real-world population-based setting.

METHODS

We used the University of Manitoba IBD Database to identify all persons in a Canadian province with CD or UC who received anti-TNF therapy between 2004 and 2016. All inpatient, outpatient, and drug costs were enumerated both in the year before anti-TNF initiation and for up to 5 years after anti-TNF initiation. Costs before and after anti-TNF initiation were compared, and multivariate linear regression analyses were performed to look for predictors of higher costs after anti-TNF initiation.

RESULTS

A total of 928 people with IBD (676 CD, 252 UC) were included for analyses. The median cost of health care in the year before anti-TNF therapy was $4698 for CD vs $6364 for UC. The median cost rose to $39,749 and $49,327, respectively, in the year after anti-TNF initiation, and to $210,956 and $245,260 in the 5 years after initiation for continuous anti-TNF users. Inpatient and outpatient costs decreased in the year after anti-TNF initiation by 12% and 7%, respectively, when excluding the cost of anti-TNFs.

CONCLUSIONS

Direct health care expenditures markedly increase after anti-TNF initiation and continue to stay elevated over pre-initiation costs for up to 5 years, with only small reductions in the direct costs of non-drug-related health care.

Relationship(s) between obesity and inflammatory bowel diseases: possible intertwined pathogenic mechanisms

The inflammatory bowel diseases, Crohn's and ulcerative colitis have increased in incidence and prevalence from the mid-eighteen to the late nineteen centuries. From then to the current twenty-first century there has been a more rapid expansion of these disease to areas previously experiencing low rates. This latter expansion coincides with the current obesity pandemic which also began toward the end of the last century. Although the two diseases have radically different frequencies, there are interesting links between them. Four areas link the diseases. On an epidemiological level, IBD tends to follow a north-south gradient raising the importance of vitamin D in protection. Obesity has very weak relationship with latitude, but both diseases follow adult lactase distributions colliding in this plane. Is it possible that obesity (a low vitamin D condition with questionable response to supplements) reduces effects in IBD? On a pathogenic level, pro-inflammatory processes mark both IBD and obesity. The similarity raises the question of whether obesity could facilitate the development of IBD. Features of the metabolic syndrome occur in both, with or without obesity in IBD. The fourth interaction between the two diseases is the apparent effect of obesity on the course of IBD. There are suggestions that obesity may reduce the efficacy of biologic agents. Yet there is some suggestion also that obesity may reduce the need for hospitalization and surgery. The apparent co-expansion of both obesity and IBD suggests similar environmental changes may be involved in the promotion of both.

Mechanisms of molecular resistance and predictors of response to biological therapy in inflammatory bowel disease

Biological therapy has led to marked improvements in treatment of patients with inflammatory bowel disease, and an increasing number of drugs has been approved for treatment. However, only a subgroup of patients responds to therapy, highlighting the need to identify biomarkers for therapeutic response to allow personalised medicine in inflammatory bowel disease. Potential markers of response to biological therapy have been identified; however, studies also suggest that changes in the composition of immune cell infiltrates in response to therapeutic pressure lead to molecular resistance to these drugs. For instance, the cytokine interleukin 23 has been identified as a driver of evasion of apoptosis in response to anti-tumour necrosis factor drugs in patients with Crohn's disease, leading to expansion of apoptosis-resistant T cells and drug resistance. In this Review, we examine the concept of molecular resistance to biological therapy and discuss implications for future therapy.

Vedolizumab Drug Level Correlation With Clinical Remission, Biomarker Normalization, and Mucosal Healing in Inflammatory Bowel Disease

BACKGROUND/AIMS

The clinical utility of vedolizumab (VDZ) trough levels (VTLs) in inflammatory bowel disease (IBD) is not well defined. The aims of this study are to determine the median VTLs and frequency of detected antibodies, the correlation of VTLs with C-reactive protein (CRP) and mucosal healing (MH), and the change in clinical management based on VTLs.

METHODS

A cross-sectional study of IBD patients treated with VDZ with VTLs checked between July 1, 2016, and March 1, 2017, was conducted. Mucosal healing was defined as absence of mucosal ulcers in Crohn's disease (CD) and Mayo endoscopic score ≤1 for ulcerative colitis (UC). Normal CRP was defined as ≤8 mg/L.

RESULTS

A total of 171 patients (62% CD, 31% UC, 7% indeterminate colitis) were included. Median VTLs was 15.3 ug/mL (range, 0-60), and 1 patient had detectable antibodies to VDZ. Patients with a normal CRP had a median VTLs of 17.3 ug/mL vs 10.7 ug/mL in high CRP patients (P = 0.046). This was noted in CD (20.3 vs 10.4 ug/mL; P = 0.005) but not in UC patients (14.4 vs 20.8; P = 0.72). Mucosal healing was achieved in 35% of patients (37 of 105); among these, median VTLs was 13.7 ug/mL vs 16.1 ug/mL in patients who did not achieve MH (P = 0.64). Vedolizumab trough levels resulted in a change in clinical management in 73%.

CONCLUSIONS

Our cohort showed a low rate of immunogenicity to VDZ and an association between VTLs and CRP in CD but not in UC patients. No relationship between VTLs and MH was detected. Vedolizumab trough level measurements altered management in approximately three fourths of patients.

Treatment Failure of TNF-α Inhibitors in Obese Patients With Inflammatory Bowel Disease-A Cohort Study

BACKGROUND

In treatment of inflammatory bowel disease (IBD) with anti-tumor necrosis factor-α agents (anti-TNF-α), obesity has been suspected as a cause of accelerated loss of response (LOR). We sought to determine whether overweight IBD patients have accelerated LOR when treated with anti-TNF-α agents, compared with normal weight IBD patients.

METHODS

We identified a cohort of adult IBD patients treated with anti-TNF-α agents at a Danish university hospital. Patients were grouped according to body mass index (BMI), and our main outcome was time to LOR. We performed survival analyses on LOR and calculated hazard ratios (HRs) with the normal weight group as the reference, while adjusting for confounders.

RESULTS

Of 210 eligible patients, 92 (44%) experienced LOR. One hundred eighty patients were treated with infliximab and 30 with adalimumab, 114 (54%) were normal weight, 51 (24%) were overweight, and 45 (21%) were obese. Regression analysis produced the following adjusted HRs, compared with the normal weight group: overweight 0.89 (95% confidence interval [CI], 0.51-1.56) and obese 1.31 (95% CI, 0.76-2.24), thus showing no statistically significant association between BMI and time to LOR. Subgroup analyses produced similar results, except for obese ulcerative colitis patients having an adjusted HR of 2.42 (95% CI, 1.03-5.70).

CONCLUSIONS

In IBD patients treated with anti-TNF-α agents, we found no overall association between increased BMI and accelerated LOR.

Review article: the relationship between obesity, bariatric surgery, and inflammatory bowel disease

BACKGROUND

The convoluted relationship between obesity, bariatric surgery and inflammatory bowel disease (IBD) is of increasing interest.

AIM

To analyse evidence regarding the role of bariatric surgery in the development of de novo IBD and its impact on clinical outcomes and safety in patients with established IBD.

METHODS

A PubMed/Medline search was performed to identify studies reporting the development of IBD after bariatric surgery and the outcomes of IBD patients after bariatric surgery.

RESULTS

Eighty patients were reported to have developed de novo IBD after bariatric surgery (21% ulcerative colitis [UC], 75% Crohn's disease [CD]), mostly females. Roux-en-Y gastric bypass was the most frequent bariatric technique (80%). Symptoms related to IBD occurred within 1 month and 16 years after surgery. Regarding patients with known IBD undergoing bariatric surgery, 60 patients (35 CD, 24 UC, and 1 unclassified colitis) have been reported. Sleeve gastrectomy was the most frequent bariatric procedure, particularly in CD patients. Acute flares after surgery were observed in only four UC patients. In addition, two retrospective population-based studies described perioperative outcomes of bariatric surgery on IBD patients, demonstrating only a significant increase in small bowel obstruction in these patients.

CONCLUSIONS

Bariatric surgery in carefully selected patients with established IBD is technically feasible and probably safe. Development of de novo IBD should be taken into account in individuals with previous bariatric surgery who develop diarrhoea, anaemia or excessive weight loss.

Obesity and Response to Infliximab in Patients with Inflammatory Bowel Diseases: Pooled Analysis of Individual Participant Data from Clinical Trials

OBJECTIVES

To assess whether obesity may affect response to infliximab, we conducted an individual participant data pooled analysis using data from clinical trials of infliximab in inflammatory bowel diseases (IBD), using the Yale Open Data Access (YODA) Project.

METHODS

We analyzed individual participant data from four clinical trials of infliximab in adults with IBD (ACCENT-I, SONIC, ACT-1, and -2). Patients were categorized as obese (body mass index [BMI] ≥ 30 kg/m²) vs. non-obese, and by quartiles based on BMI or weight at time of trial entry. Primary outcome was clinical remission (Crohn's disease activity index [CDAI] < 150 or pediatric CDAI <10, Mayo Clinic Score <3); secondary outcomes were clinical response and mucosal healing. Multivariable logistic regression analysis was performed, after adjusting for sex, smoking, disease activity, and concomitant prednisone and/or immunomodulators.

RESULTS

We included 1205 infliximab-treated patients (mean age 37 years, 51.6% males, 14% obese). Obesity was not associated with odds of achieving clinical remission (obese vs. non-obese: adjusted OR, 0.93 [95% CI, 0.47-1.46]; Q4 vs. Q1: aOR, 0.94 [0.61-1.47], p-value for trend = 0.97), clinical response (Q4 vs. Q1: aOR, 0.84 [0.52-1.35], p = 0.45) or mucosal healing (Q4 vs. Q1: aOR, 1.13 [0.55-2.34], p = 0.95). These results were consistent across strata based on disease type (Crohn's disease and ulcerative colitis) and trial design (induction and maintenance therapy).

CONCLUSIONS

Based on individual participant data pooled analysis, obesity is not associated with inferior response to infliximab in patients with IBD. Future studies examining the association between obesity and fixed-dose therapies are warranted.

Anti-TNF Therapeutic Drug Monitoring in Postoperative Crohn's Disease

BACKGROUND

Anti-TNF prevents postoperative Crohn's disease recurrence in most patients but not all. This study aimed to define the relationship between adalimumab pharmacokinetics, maintenance of remission and recurrence.

METHODS

As part of a study of postoperative Crohn's disease management, some patients undergoing resection received prophylactic postoperative adalimumab. In these patients, serum and fecal adalimumab concentration and serum anti-adalimumab antibodies [AAAs] were measured at 6, 12 and 18 months postoperatively. Levels of Crohn's disease activity index [CDAI], C-reactive protein [CRP] and fecal calprotectin [FC] were assessed at 6 and 18 months postoperatively. Body mass index and smoking status were recorded. A colonoscopy was performed at 6 and/or 18 months.

RESULTS

Fifty-two patients [32 on monotherapy and 20 on combination therapy with thiopurine] were studied. Adalimumab concentration did not differ significantly between patients in endoscopic remission vs recurrence [Rutgeerts ≥ i2] [9.98µg/mL vs 8.43 µg/mL, p = 0.387]. Patients on adalimumab monotherapy had a significantly lower adalimumab concentration [7.89 µg/mL] than patients on combination therapy [11.725 µg/mL] [p = 0.001], and were significantly more likely to have measurable AAA [31% vs 17%, p = 0.001]. Adalimumab concentrations were lower in patients with detectable AAA compared with those without [3.59 µg/mL vs 12.0 µg/mL, p < 0.001]. Adalimumab was not detected in fecal samples. Adalimumab serum concentrations were lower in obese patients compared with in non-obese patients [p = 0.046].

CONCLUSION

Adalimumab concentration in patients treated with adalimumab to prevent symptomatic endoscopic recurrence postoperatively is, for most patients, well within the therapeutic window, and is not significantly lower in patients who develop recurrence compared with in those who remain in remission. Mechanisms of anti-TNF failure to prevent postoperative recurrence remain to be determined in these patients.

Should we use anti-tumor necrosis factor agents or vedolizumab as first-line biological therapy in ulcerative colitis?

Randomized controlled trials with direct comparisons between the different available biological agents in ulcerative colitis are lacking. The comparative efficacy, safety and tolerability, patient profile, patient preference and costs should be taken into account when choosing an appropriate first-line biological. Tumor necrosis factor antagonists have a systemic mode of action, while vedolizumab is mainly gut-selective, and this influences the clinical profile of both treatment options. Tofacitinib will further expand the therapeutic armamentarium in ulcerative colitis. Results of ongoing head-to-head trials between biological agents are likely to change clinical practice in the near future. Biomarkers that predict response to different treatment options in an individual patient are warranted.

Impact of obesity on the efficacy of different biologic agents in inflammatory diseases: A systematic review and meta-analysis

OBJECTIVE

Obesity is a worldwide epidemic and a growing body of evidence suggests that it may affect the body's response to biologic agents. We investigated the influence of obesity on the efficacy of different biologic agents used to treat inflammatory diseases.

METHODS

Medline, EMBASE and the Cochrane Database were searched using relevant MeSH and keyword terms for obesity and bDMARDs. Articles were selected if they reported a clinical response in obese subjects relative to other BMI categories. Response and remission outcomes were assessed using meta-analysis and all other reported outcomes were summarized.

RESULTS

Among the 3850 records retrieved, 24 articles met the inclusion criteria, including 10 on rheumatoid arthritis (RA), 4 on axial spondyloarthritis (axSpA), 4 on Crohn's disease (CD), 4 on psoriasis (Ps) and 2 on psoriasic arthritis (PsA). Four biological disease-modifying anti-rheumatic drugs (bDMARDs) - anti-TNF agents, T cell co-stimulation inhibitor (abatacept), IL-6 inhibitor (tocilizumab), and B-cell depletion therapy (rituximab) - were involved. The meta-analysis showed that the odds to reach a good response or achieve remission were lower in obese (BMI>30kg/m²) than non-obese (BMI≤30kg/m²) patients who were treated with anti-TNF agents (good responder % in RA: OR 0.34, 95% CI 0.18-0.64; remission% in RA: OR 0.36, 95% CI 0.21-0.59; BASDAI50% in axSpA: OR 0.41, 95% CI 0.21-0.83), but no significant difference between obese and non-obese was found in patients treated with abatacept (good responder % in RA: OR 0.75, 95% CI 0.42-1.36; remission% in RA: OR 0.84, 95% CI 0.65-1.09) and tocilizumab (good responder % in RA: OR 1.08, 95% CI 0.44-2.63; remission% in RA: OR 0.91, 95% CI 0.50-1.66).

CONCLUSION

Obesity hampered the effect of anti-TNF agents, but not those of abatacept and tocilizumab, suggesting that a personalized treatment strategy should be considered for obese patients with inflammatory diseases.

Obesity and inflammatory bowel disease: diagnostic and therapeutic implications

PURPOSE OF REVIEW

The review summarizes our current understanding of how obesity impacts diagnostic studies and therapies used in inflammatory bowel disease (IBD) as well as the safety and efficacy of medical and surgical weight loss therapies in the obese IBD patient.

RECENT FINDINGS

Many of the diagnostic tools we rely on in the identification and monitoring of IBD can be altered by obesity. Obesity is associated with increased acute phase proteins and fecal calprotectin. It can be more difficult to obtain and interpret cross sectional imaging of obese patients. Recent studies have also shown that common therapies used to treat IBD may be less effective in the obese population and may impact comorbid disease. Our understanding of how best to measure obesity is evolving. In addition to BMI, studies now include measures of visceral adiposity and subcutaneous to visceral adiposity ratios. An emerging area of interest is the safety and efficacy of obesity treatment including bariatric surgery in patients with IBD. A remaining question is how weight loss may alter the course of IBD.

SUMMARY

The proportion of obese IBD patients is on the rise. Caring for this population requires a better understanding of how obesity impacts diagnostic testing and therapeutic strategies. The approach to weight loss in this population is complex and future studies are needed to determine the safety of medical or surgical weight loss and its impact on the course of disease.

Obesity and Pediatric Drug Development

There is a lack of dosing guidelines for use in obese children. Moreover, the impact of obesity on drug safety and clinical outcomes is poorly defined. The paucity of information needed for the safe and effective use of drugs in obese patients remains a problem, even after drug approval. To assess the current incorporation of obesity as a covariate in pediatric drug development, the pediatric medical and clinical pharmacology reviews under the Food and Drug Administration (FDA) Amendments Act of 2007 and the FDA Safety and Innovation Act (FDASIA) of 2012 were reviewed for obesity studies. FDA labels were also reviewed for statements addressing obesity in pediatric patients. Forty-five drugs studied in pediatric patients under the FDA Amendments Act were found to have statements and key words in the medical and clinical pharmacology reviews and labels related to obesity. Forty-four products were identified similarly with pediatric studies under FDASIA. Of the 89 product labels identified, none provided dosing information related to obesity. The effect of body mass index on drug pharmacokinetics was mentioned in only 4 labels. We conclude that there is little information presently available to provide guidance related to dosing in obese pediatric patients. Moving forward, regulators, clinicians, and the pharmaceutical industry should consider situations in drug development in which the inclusion of obese patients in pediatric trials is necessary to facilitate the safe and effective use of new drug products in the obese pediatric population.

Body mass index influences infliximab post-infusion levels and correlates with prospective loss of response to the drug in a cohort of inflammatory bowel disease patients under maintenance therapy with Infliximab

Introduction

Infliximab is an effective treatment for inflammatory bowel disease (IBD). Studies differ regarding the influence of body mass index (BMI) on the response to infliximab, with the majority of studies indicating that increased BMI may be associated with a poorer response to Infliximab. However, the pharmacokinetic mechanisms causing this have not yet been reported.

Aims

Examine the correlation between BMI/immunosuppressant use with clinical response, trough and post-infusion levels of infliximab, tumour necrosis factor-α(TNF-α) and anti-drug antibodies(ATI), and determine if these factors can predict future response.

Methods

We collected serum from 24 patients receiving Infliximab before and 30 minutes following infusion. Clinical parameters were collected retrospectively and prospectively. ELISA measurements of infliximab, TNF-α and ATI were performed.

Results

We confirmed that patients with higher infliximab trough levels have a better response rate and that patients with an elevated BMI display a higher rate of loss of response (20%). Patients with a higher BMI had elevated post-infusion levels of infliximab. Additionally, the ratio of IFX/TNF-α trough levels correlated with clinical response to the following infusion.

Conclusion

This study confirms that an elevated BMI is associated with a poorer response to infliximab. For the first time, we describe that a higher BMI correlates with higher post-infusion levels, however this does not correlate with a higher rate of response to the drug, suggesting that circulating drug levels do not correlate with tissue levels. Furthermore, in our small cohort of patients, we identified a possible predictive marker of future response to treatment which may be used to guide dose escalation and predict non-response to infliximab.

Extraintestinal Manifestations Are Common in Obese Patients with Crohn's Disease

INTRODUCTION

Crohn's disease (CD) is a chronic condition associated with the risk of malabsorption. The incidence of obesity worldwide is increasing, and the effect of obesity on patients with CD is unknown. We aim to identify traits related to obesity in a cohort of patients with CD.

METHODS

We conducted a retrospective study of 209 adult patients with CD. Age, Montreal disease classification, sex, race, duration of disease, erythrocyte sedimentation rate, C-reactive protein levels, physician global assessment, endoscopic appearance, histologic activity, medication use, and body mass index (BMI) were collected about each patient.

RESULTS

The mean age was 43.4 ± 14.9 years; 68.9% were white, and 51.7% were male. The mean duration of disease was 11.0 ± 10.6 years. The mean BMI was 26.8 ± 5.7: underweight 7.7%; normal weight 29.3%; overweight 38.0%; and obese 25%. Patients with higher BMI were more likely to have extraintestinal manifestations (EIM) (P = 0.005) and more likely to have nonarthralgia extraintestinal manifestations (P = 0.047). There was a linear association between proximal CD and decreasing BMI (underweight 31.3%, normal weight 14.8%, overweight 15.0%, obese 7.7%; P = 0.046). There was no difference in BMI between patients with and without perianal disease (P = 0.216).

CONCLUSIONS

Most patients were overweight or obese, which correlates with national population trends. Our data suggest disease location plays a role in weight modulation in patients with CD. Increased extraintestinal manifestations in patients with high BMI suggests that the chronic inflammation associated with obesity may play a role in extraintestinal inflammation.

Comparison of Infliximab and Adalimumab in Biologic-Naive Patients With Ulcerative Colitis: A Nationwide Danish Cohort Study

BACKGROUND & AIMS

This study compares the effectiveness and safety of infliximab and adalimumab in biologic-naive patients with ulcerative colitis (UC), in a nationwide register-based propensity score-matched cohort study.

METHODS

From 1719 adults with UC, between ages 15 and 75 years in Denmark treated with either infliximab or adalimumab as their first biologic agent, we compared rates of all-cause hospitalization, UC-related hospitalization, major abdominal surgery, and serious infections after a variable 2:1 propensity score matching, accounting for baseline clinical characteristics, disease severity, health care utilization, and use of UC-related medications.

RESULTS

As compared with infliximab-treated patients, adalimumab-treated patients had higher rate of all-cause hospitalization (hazard ratio [HR], 1.84; 95% CI, 1.18-2.85) and a trend toward higher rate of UC-related hospitalization (HR, 1.71; 95% CI, 0.95-3.07), particularly in a stratum of patients on concomitant immunomodulator therapy. However, risk of abdominal surgery (HR, 1.35; 95% CI, 0.62-2.94) was not different between the 2 treatment groups. Risk of serious infection requiring hospitalization was significantly higher in adalimumab-treated patients (HR, 5.11; 95% CI, 1.20-21.80).

CONCLUSIONS

In this nationwide propensity score matched-cohort study of biologic-naive adults with UC, use of adalimumab as first-line biologic over infliximab was associated with higher risk of hospitalization and serious infections, although risk of surgery was not different. In the absence of head-to-head trials, this evidence may assist patients, health care providers, purchasers, and policy makers to make informed decisions that may improve health care in UC.

Dose escalation of biologics in Crohn's disease: critical review of observational studies

BACKGROUND

Biologics used to treat Crohn's disease (CD) may lose their effect over time, requiring dose escalation. Little information is available on this topic.

AIM

To summarize rates of dose escalation, duration, de-escalation in observational studies of CD in adults treated with adalimumab, infliximab, and vedolizumab in Europe.

METHODS

Two independent investigators searched Medline and Embase for observational studies published in 1998-2015 and proceedings from four major scientific meetings. Rates were summarized descriptively.

RESULTS

In total, 58 articles from 12 European countries were analyzed (49 full articles, nine abstracts), providing 65 reports with 7,850 patients; 35 reported on 3,830 patients with adalimumab (ADA), and 30 on 4,020 patients with infliximab (IFX). Overall, 29.9% ± 3.5% of patients required dose escalation; 32.8% ± 6.2% with ADA and 25.2% ± 2.4% with IFX (p = .35 between drugs). Rates increased according to line of treatment: 19% for first line, 37% second, and 41% third. The median time to loss of response was 12 months, and the weighted average was 15.1 ± 5.9 months. Median time to escalation was 6.7 months; 6.7 months for ADA and 7.5 for IFX (p = .86). Short-term response rates to escalation were 63% for ADA and 45% for IFX (p = .08). There were no papers available for vedolizumab.

CONCLUSIONS

A substantial proportion of patients receiving ADA or IFX for Crohn's disease require dose escalation after a short period of time.

Sarcopenia Is Common in Overweight Patients with Inflammatory Bowel Disease and May Predict Need for Surgery

BACKGROUND

Inflammatory bowel disease (IBD) is associated with altered body composition, such as low muscle mass, which affects clinical outcomes. Body composition changes in overweight patients with IBD are less understood. The study aim was to determine the prevalence of sarcopenic overweight and obese patients in a cohort of patients with IBD starting new anti-tumor necrosis factor-α therapy and examine differences in response.

METHODS

This is a retrospective review of patients with IBD starting a new anti-tumor necrosis factor-α medication that had computed tomography within 3 months of initiation. L3 vertebral slice was used for segmentation of body composition and identification of sarcopenia. CRP, ESR, Harvey Bradshaw Index, albumin, 25-OH vitamin D, and body mass index at anti-tumor necrosis factor-α initiation and at 6 months were collected. Outcomes included hospitalization, need for surgery, or new biological medication.

RESULTS

Ninety patients were studied. Forty-one of ninety (45%) were sarcopenic; of these, 17 (41.5%) had a normal body mass index and 8 (19.5%) were overweight/obese. More men were sarcopenic (68% versus 32%, P < 0.001). CRP was higher and albumin lower in sarcopenic subjects. Sarcopenia did not predict outcomes in the cohort but was the only significant predictor of need for surgery in overweight and obese subjects (P = 0.002).

CONCLUSIONS

Almost half of our cohort was sarcopenic. Most of these patients are normal or overweight and would not be identified as malnourished by traditional measures. Sarcopenia was a predictor of surgery in patients with a body mass index ≥ 25. Identification of sarcopenia has implications for medical nutrition therapy as typically efforts are focused on underweight patients.

Gastrointestinal Complications of Obesity

Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett's esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions.

Low muscle mass at initiation of anti-TNF therapy for inflammatory bowel disease is associated with early treatment failure: a retrospective analysis

BACKGROUND/OBJECTIVES

Delayed treatment failure occurs in a significant proportion of inflammatory bowel disease (IBD) patients treated with tumor necrosis factor-alpha (TNF) antagonists. Identification of predictors of loss of response (LOR) may help to optimize therapy. We sought to determine whether body composition parameters at the commencement of anti-TNF therapy were associated with earlier treatment failure.

SUBJECTS/METHODS

A retrospective cohort study was performed on 68 patients who had undergone cross-sectional abdominal imaging coincident with the commencement of anti-TNF drugs. Analysis of the images at the third lumbar vertebra was performed using standard techniques to determine cross-sectional areas of skeletal muscle (SM), visceral adipose tissue, subcutaneous adipose tissue and intermuscular adipose tissue. Treatment failure was defined as: post-induction hospital admission or surgery for IBD, escalation of TNF dose or immunosuppressants for clinical LOR, emergence of a new fistula or Crohn's Disease Activity Index (CDAI) >150.

RESULTS

Two-thirds of patients had myopenia. Patients with less than gender-specific median SM area had a median time to failure of 520 (s.d. 135) days compared to 1100 (s.d. 151) days for those with more than median SM area (P=0.036). No difference was found in disease duration, inflammatory markers or CDAI between quartiles of SM area. No relation between outcomes and measures of adipose tissue, weight or body mass index was observed.

CONCLUSIONS

Identifying low muscle mass at anti-TNF induction as a risk factor for treatment failure may contribute to a more tailored approach to IBD therapy.

Obesity in IBD: epidemiology, pathogenesis, disease course and treatment outcomes

Incidence of IBD is rising in parallel with overweight and obesity. Contrary to conventional belief, about 15-40% of patients with IBD are obese, which might contribute to the development of IBD. Findings from cross-sectional and retrospective cohort studies are conflicting on the effect of obesity on natural history and course of IBD. Most studies are limited by small sample size, low event rates, non-validated assessment of disease activity and lack robust longitudinal follow-up and have incomplete adjustment for confounding factors. The effect of obesity on the efficacy of IBD-related therapy remains to be studied, though data from other autoimmune diseases suggests that obesity results in suboptimal response to therapy, potentially by promoting rapid clearance of biologic agents leading to low trough concentrations. These data provide a rationale for using weight loss interventions as adjunctive therapy in patients with IBD who are obese. Obesity also makes colorectal surgery technically challenging and might increase the risk of perioperative complications. In this Review, we highlight the existing literature on the epidemiology of obesity in IBD, discuss its plausible role in disease pathogenesis and effect on disease course and treatment response, and identify high-priority areas of future research.

Pharmacogenetics of ustekinumab in patients with moderate-to-severe plaque psoriasis

Aim/Materials & methods: Few studies have evaluated the influence of pharmacogenetics in psoriatic patients treated with ustekinumab. We evaluated 121 polymorphisms to study a possible association between these SNPs and the response to ustekinumab (PASI75 at 4 months; n = 69). Results/Conclusion: The adjusted results (false discovery rate) showed an association between five SNPs in TNFRSF1A, HTR2A, NFKBIA, ADAM33 and IL13 genes, and poor response to ustekinumab. Furthermore, six SNPs in CHUK, C17orf51, ZNF816A, STAT4, SLC22A4 and Corf72 genes were associated with better response to ustekinumab. However, there was no significant association between response to ustekinumab and SNPs in HLA-C as it has been recently described. Finally, a higher weight was obtained in nonresponders than responders (p = 0.018). Further studies would be necessary to be closer to personalized medicine.

The Changing Phenotype of Inflammatory Bowel Disease

It is widely known that there have been improvements in patient care and an increased incidence of Inflammatory Bowel Disease (IBD) worldwide in recent decades. However, less well known are the phenotypic changes that have occurred; these are discussed in this review. Namely, we discuss the emergence of obesity in patients with IBD, elderly onset disease, mortality rates, colorectal cancer risk, the burden of medications and comorbidities, and the improvement in surgical treatment with a decrease in surgical rates in recent decades.

Comparative Effectiveness and Safety of Anti-Tumor Necrosis Factor Agents in Biologic-Naive Patients With Crohn's Disease

BACKGROUND & AIMS

Inhibitors of tumor necrosis factor (anti-TNF agents) are the most effective therapy for Crohn's disease (CD). We evaluated the real-world comparative effectiveness and safety of different anti-TNF agents (infliximab, adalimumab, and certolizumab pegol) in biologic-naive patients with CD in a retrospective, propensity-matched cohort study using a national administrative claims database (Optum Labs Data Warehouse).

METHODS

We identified 3205 biologic-naive patients with CD (mean age, 41 ± 15 years; 45% male; median follow-up period after anti-TNF therapy, 19 months; 44.5% on infliximab and 38.9% on adalimumab) who received their first prescription for an anti-TNF agent (infliximab, adalimumab, or certolizumab pegol) after a 12-month period without any anti-TNF treatment (baseline), and with a minimum follow-up period of 6 months after their initial anti-TNF prescription, between 2006 and 2014. The primary outcomes were all-cause and CD-related hospitalization, abdominal surgery, corticosteroid use, and serious infections. We performed a propensity-matched, Cox proportional hazards analysis, accounting for baseline demographics, health care use, comorbidities, and use of CD-related medication.

RESULTS

Compared with adalimumab-treated patients, infliximab-treated patients had a lower risk of CD-related hospitalization (adjusted hazard ratio [aHR], 0.80; 95% confidence interval [CI], 0.66-0.98), abdominal surgery (aHR, 0.76; 95% CI, 0.58-0.99), and corticosteroid use (aHR, 0.85; 95% CI, 0.75-0.96). Compared with certolizumab pegol-treated patients, infliximab-treated patients had a lower risk of all-cause hospitalization (aHR, 0.70; 95% CI, 0.52-0.95) and CD-related hospitalization (aHR, 0.59; 95% CI, 0.39-0.90). Adalimumab-treated patients had outcomes comparable with those of certolizumab pegol-treated patients. All agents had comparable risk of serious infections.

CONCLUSIONS

In a retrospective analysis of a large cohort of biologic-naive patients with CD, we found infliximab to be superior to adalimumab and certolizumab pegol for patient-relevant outcomes, without increased risk of serious infections.

Optimizing Treatment with TNF Inhibitors in Inflammatory Bowel Disease by Monitoring Drug Levels and Antidrug Antibodies

BACKGROUND

Biological tumor necrosis factor (TNF) inhibitors have revolutionized the treatment of inflammatory bowel disease and redefined treatment goals to include mucosal healing. Clinicians are faced with challenges such as inadequate responses, treatment failures, side effects, and high drug costs. The objective is to review optimization of anti-TNF therapy by use of personalized treatment strategies based on circulating drug levels and antidrug antibodies (Abs), i.e. therapeutic drug monitoring (TDM). Furthermore, to outline TDM-related pitfalls and their prevention.

METHODS

Literature review.

RESULTS

Circulating anti-TNF drug trough level is a marker for the pharmacokinetics (PK) of TNF inhibitors. Because of a number of factors, including antidrug antibodies, PK varies between and within patients across time leading to variable clinical outcomes. Differences in intestinal inflammatory phenotype influencing the pharmacodynamic (PD) responses to TNF inhibitors also affect treatment outcomes. As an alternative to handling anti-TNF-treated patients by empiric strategies, TDM identifies underlying PK and PD-related reasons for treatment failure and aids decision making to secure optimal clinical and economic outcomes. Although promising, evidence does not the support use of TDM to counteract treatment failure in quiescent disease. Use of TDM is challenged by methodological biases, difficulties related to differentiation between PK and PD problems, and temporal biases due to lack of chronology between changes in PK versus symptomatic and objective disease activity manifestations. Biases can be accommodated by knowledgeable interpretation of results obtained by validated assays with clinically established thresholds, and by repeated assessments over time using complimentary techniques.

CONCLUSIONS

TDM-guided anti-TNF therapy at treatment failure has been brought from bench to bedside.

Considerations, challenges and future of anti-TNF therapy in treating inflammatory bowel disease

INTRODUCTION

Crohn's disease (CD) and ulcerative colitis (UC) are chronic disabling conditions. Monoclonal antibody therapy directed against tumor necrosis factor-alpha (anti-TNF) has revolutionized the care of patients with inflammatory bowel disease (IBD).

AREAS COVERED

Considerations before starting anti-TNF therapy are highlighted: the best time to start with anti-TNF therapy, either alone or in combination with an immunomodulator, the choice of an anti-TNF agent and the contra-indications to anti-TNF therapy. Primary nonresponse and secondary loss of response are discussed. De-escalating therapy, the role of therapeutic drug monitoring and the use of biosimilars, are handled. Finally, the future directions of anti-TNF therapy are emphasized.

EXPERT OPINION

Anti-TNF therapy remains the cornerstone in the treatment of IBD. When initiating long-term therapy, safety and cost issues are of great importance. The therapeutic armamentarium in the treatment of IBD is rapidly growing. Therefore, the challenge is to optimize the use and refine the exact position of anti-TNF therapy in the near future, with personalized medicine as the ultimate goal.

Predicting durable response or resistance to antitumor necrosis factor therapy in inflammatory bowel disease

Monoclonal antibodies to tumor necrosis factor (TNF) have become a mainstay of the therapeutic armamentarium in inflammatory bowel disease (IBD) over the last 15 years. Although highly effective, primary and secondary nonresponse are common and associated with poor clinical outcomes and significant costs. Multiple clinical, genetic and immunopharmacological factors may impact the response to anti-TNFs. Early stratification of IBD patients by the expected risk of therapeutic failure during the induction and maintenance phases of treatment may allow for treatment optimization and potentially optimal short- and long-term outcomes. The aim of this review is to summarize the current data concerning the potential predictors of therapeutic success and failure of anti-TNFs in IBD.