Systematic review: adipose tissue, obesity and gastrointestinal diseases

Development and assessment of an intestinal tri-cellular model to investigate the pro/anti-inflammatory potential of digested foods

Introduction

Immunonutrition, defined as the potential of foods, nutrients and dietary patterns to modulate the immune system activity, has been proposed as a strategy to enhance the immune response in both metabolic and immune-mediated diseases. However, the anti-/pro-inflammatory role of foods and diets is far to be fully ascertained, and thus there is a continued needed for appropriate in vitro cell-culture models to investigate the role of foods in modulating cell-mediated inflammatory processes. This study aims to develop and test an in vitro tri-culture model, simulating the complexity of the intestinal tract and its multiple cell interactions.

Methods

To achieve this, the intestinal epithelial barrier was established by co-culturing human Caco-2 enterocyte-like and HT29-MTX-E12 mucus producing goblet-like colon cells, then adding human monocyte THP-1 cells to the basolateral compartment. The integrity and stability of the epithelial barrier were monitored and the inflammatory response of the model was assessed using various stressors at different concentrations, both individually and in combination (phorbol-12- myristate-13-acetate or PMA, and lipopolysaccharide or LPS), in terms of cytokines production. To test the model, different concentrations of in vitro digested broccoli (BD) were added to the apical section of the model.

Results

Supernatants from the basolateral compartment were collected and analyzed for cytokines production (IL-6, TNF-α, IL-12p70, IL-18 and IL-8) using automated ELISA (ELLA). Additionally, ZO-1 protein from the tight junctions of epithelial cells was analyzed by flow cytometry. The results indicated that 100 nM PMA added to the whole model for 20 h was the best stressor to simulate a mild-inflammatory status of the gut. Following treatment with BD, IL-6, TNF-α, IL-8 and IL-18 were significantly reduced compared to the control group, while ZO-1 expression increased at the lowest BD concentration.

Conclusions

These findings confirm the feasibility of the model for assessing the effects of food digesta on specific cytokines and permeability markers, representing a valuable strategy for investigating the role of foods in modulating the inflammatory response. The results obtained may support dietary strategies aimed at promoting wellbeing and preventing inflammatory-related metabolic diseases.

Metabolic dysfunction-associated steatotic liver disease and gallbladder polyp development: an observational study

The influence of metabolic dysfunction-associated steatotic liver disease (MASLD) on gallbladder polyp development in both sexes remains elusive. Therefore, to clarify the role of MASLD in gallbladder polyp development, we investigated the longitudinal association between MASLD and gallbladder polyps. In this observational study, we included 5,527 gallbladder polyp-free patients who underwent > 2 health check-ups over > 2 years. Generalized estimation equations were used to analyze associations between MASLD and gallbladder polyp development according to repeated measures at baseline and the most recent stage. Gallbladder polyp development rates in men and women were 7.5% and 5.6% (p < 0.01), respectively. MASLD was not significantly correlated with gallbladder polyp development. Regarding the association between gallbladder polyp development (men: ≥6 mm and women: ≥5 mm) and the number of MASLD components following lifestyle habits, men and women with ≥ 4 MASLD components had odds ratios of 3.397 (95% confidence interval: 1.096-10.53) and 5.338 (1.054-27.04), respectively. Higher nonalcoholic fatty liver disease fibrosis scores were associated with significant risk of gallbladder polyp development in women (1.991, 1.047-3.785). Although MASLD influence on gallbladder polyp development differs by sex, close monitoring of patients with an increasing number of MASLD components is essential to prevent gallbladder polyp development. Specifically, men with ≥ 4 MASLD components should be monitored for gallbladder polyps measuring ≥ 6 mm.

Amino acid HPLC-FLD analysis of spirulina and its protective mechanism against the combination of obesity and colitis in wistar rats

Objective

The cafeteria diet (CD), designed as an experimental diet mimicking the obesogenic diet, may contribute to the pathogenesis of inflammatory bowel diseases (IBD). This study delves into the influence of spirulina (SP) on obesity associated with colitis in Wistar rats.

Methods

The amino acids composition of SP was analyzed using HPLC-FLD. Animals were equally separated into eight groups, each containing seven animals and treated daily for eight weeks as follows: Control diet (SD), cafeteria diet (CD) group, CD + SP (500 mg/kg) and SD + SP. Ulcerative colitis was provoked by rectal injection of acetic acid (AA) (3 % v/v, 5 ml/kg b.w.) on the last day of treatment in the following groups: SD + AA, SD + AA + SP, CD + AA, and CD + AA + SP.

Results

Findings revealed that UC and/or CD increased the abdominal fat, weights gain, and colons. Moreover, severe colonic alteration, perturbations in the serum metabolic parameters associated with an oxidative stress state in the colonic mucosa, defined by overproduction of reactive oxygen species (ROS) and increased levels of plasma scavenging activity (PSA). Additionally, obesity exacerbated the severity of AA-induced UC promoting inflammation marked by the overexpression of pro-inflammatory cytokines. Significantly, treatment with SP provided notable protection against inflammation severity, reduced histopathological alterations, attenuated lipid peroxidation (MDA), and enhanced antioxidant enzyme activities (CAT, SOD, and GPX) along with non-enzymatic antioxidants (GSH and SH-G).

Conclusions

Thus, the antioxidant effects and anti-inflammatory proprieties of SP could be attributed to its richness in amino acids, which could potentially mitigate inflammation severity in obese subjects suffering from ulcerative colitis. These results imply that SP hold promise as a therapeutic agent for managing of UC, particularly in individuals with concomitant obesity. Understanding SP's mechanisms of action may lead novel treatment strategies for inflammatory bowel diseases and hyperlipidemia in medical research.

Understanding the gastrointestinal tract in obesity: From gut motility patterns to enzyme secretion

BACKGROUND AND PURPOSE

The pathophysiology of obesity has been the product of extensive research, revealing multiple interconnected mechanisms contributing to body weight regulation. The regulation of energy balance involves an intricate network, including the gut-neuroendocrine interplay. As a consequence, research on the gut-brain-microbiota axis in obesity has grown extensively. The physiology of the gastrointestinal tract, far from being underexplored, has significant implications for the development of specific complications in people living with obesity across the fields of gastroenterology, nutrition, and pharmacology. Clinical research indicates higher fasting bile acids serum levels, and blunted postprandial increases in bilious secretions in people living with obesity. Findings are less straightforward for the impact of obesity on gastric emptying with various studies reporting accelerated, normal, or delayed gastric emptying rates. Conversely, the effect of obesity on gastrointestinal pH, gastrointestinal transit, and gastric and pancreatic enzyme secretion is largely unknown. In this review, we explore the current evidence on the gastrointestinal physiology of obesity.

Short-term outcomes of bariatric surgery in patients with inflammatory bowel disease: a national analysis

BACKGROUND

While considered standard of care for obesity management, bariatric surgery is uncommon in patients with co-morbid inflammatory bowel disease (IBD).

OBJECTIVES

The present study aimed to assess the association of IBD with postoperative outcomes and resource use following bariatric surgery.

SETTING

Academic, university-affiliated; United States.

METHODS

All elective adult hospitalizations for laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB) were identified in the 2016-2019 Nationwide Readmissions Database. Patients were classified based on diagnosis of ulcerative colitis (UC) or Crohn's disease (CD). Multivariable regression models were developed to evaluate the association of IBD with outcomes of interest.

RESULTS

Of an estimated 719,270 eligible patients, 860 and 1214 comprised the UC and CD cohorts, respectively. Compared to non-IBD, UC and CD had a higher Elixhauser comorbidity index (UC: 3.0 ± 1.4; CD: 3.1 ± 1.5; non-IBD: 2.7 ± 1.4, P < .001) and more frequently underwent sleeve gastrectomy (UC: 77.5%; CD: 83.2%; non-IBD: 68.8%, P < .001). All IBD patients survived to discharge. After adjustment, IBD was not associated with significant differences in most clinical outcomes analyzed. UC (adjusted odds ratio: 2.86; 95% confidence interval: 1.14-7.13) and CD (adjusted odds ratio: 4.40; 95% confidence interval: 2.20-8.80) were associated with increased odds of gastric outlet obstruction after RYGB but not sleeve gastrectomy. CD, but not UC, was linked to significantly higher odds of small bowel obstruction following RYGB (adjusted odds ratio: 4.50; 95% confidence interval: 1.76-11.49). There was no difference in index LOS, hospitalization costs, or odds of 30-day readmission based on IBD.

CONCLUSIONS

Patients with obesity and IBD faced low rates of adverse outcomes following bariatric surgery. There is an increased risk of gastrointestinal obstruction for patients with IBD undergoing RYGB. Given its safety profile, bariatric surgery can be utilized as a weight loss intervention for the growing proportion of patients with obesity and co-morbid IBD.

Metabolic syndrome and risk of colorectal cancer: A Mendelian randomization study

Background

Observational studies have previously demonstrated a significant relationship among both metabolic syndrome (Mets) and colorectal cancer (CRC). Whether there is a causal link remains controversial.

Objective

To clarify whether Mets and their components have a causal effect on colorectal cancer, we have carried out a bidirectional Mendelian randomization analysis (MR).

Methods

This study started from genome-wide association data for Mets and its 5 components (hypertension, waist circumference, fasting blood glucose, serum triglycerides, and serum high-density lipoprotein cholesterol) and colorectal cancer. Mendelian randomization (MR) techniques were used in the study to examine their associations.

Results

After Benjamini-Hochberg multiple corrections, genetically predicted significant causal link exists between WC (waist circumference) and CRC. The OR was 1.35 (95 % CI: 1.08-1.69; p = 0.0096). Other Mets components (HBP, FBG, TG, HDL), on the other hand, found no evidence of a genetic link between CRC and Mets. In addition, MR results showed that CRC was not causally related to either Mets or the components. We get the same result in the validated dataset.

Conclusion

According to the bidirectional MR investigation shows a significant causal relationship among obesity and CRC in the Mets component but no causal relationship in the opposite direction.

A positive association of serum CCN5/WISP2 levels with the risk of developing gestational diabetes mellitus: a case-control study

INTRODUCTION

CCN5/WISP2 is prominently manifest in adipose tissue and has been linked to the pathogenesis of obesity, diabetes, and insulin resistance. However, discrepancies exist in previous studies, and little is known about its association with gestational diabetes mellitus (GDM). The current investigation is designed to examine the correlation of WISP2 with risk factors in GDM patients in comparison to healthy pregnant women for the first time.

METHODS

This case-control study measured serum levels of CCN5, TNF-α, IL-6, adiponectin, and fasting insulin using ELISA kits in 88 GDM patients and 88 pregnant women.

RESULTS

The GDM group had remarkably higher serum levels of CCN5 (379.41 ± 83.078 ng/ml) compared to controls (212.02 ± 77.935 ng/ml). In a similar vein, it was observed that patients diagnosed with GDM exhibited elevated levels of pro-inflammatory cytokines such as IL-6 and TNF-α; while conversely, adiponectin levels were found to be significantly lower than those observed in the control group (P < 0.0001). In women with GDM, a positive and significant correlation was observed between CCN5 and BMI, FBG, insulin, HOMA-IR, as well as IL-6 and TNF-α levels. In the adjusted model, the risk of GDM was significantly increased with elevated serum CCN5 level.

CONCLUSION

Our research indicates a noteworthy and affirmative correlation between the levels of CCN5 in the serum and the risk of developing GDM, along with its associated risk factors such as BMI, insulin resistance index, FBG, and inflammatory cytokines (TNF-α and IL-6). These findings suggest that CCN5 could potentially play a role in the etiology of GDM.

The Medical Burden of Obesity and Overweight in the US Military: Association of BMI with Clinically Diagnosed Medical Conditions in United States Military Service Members

BACKGROUND

A high BMI is associated with various medical conditions, notably type 2 diabetes, cardiovascular disease, and mental health disorders. In the US military, BMI increased linearly between 1975 and 2015.

OBJECTIVE

This cross-sectional study investigated the associations between BMI and a comprehensive range of clinically diagnosed medical conditions (CDMCs) in US military service members (SMs).

METHODS

A stratified random sample of SMs (n=26,177) completed an online questionnaire reporting their height, weight, and demographic/lifestyle characteristics. Medical conditions for 6 mo before questionnaire completion were obtained from a comprehensive military electronic medical surveillance system and grouped into 39 CDMCs covering both broad (largely systemic) and specific medical conditions. BMI was calculated as weight/height2 (kg/m2). The prevalence of CDMCs was compared among normal weight (<25.0 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30 kg/m2) SMs.

RESULTS

After multivariable adjustment for demographic/lifestyle characteristics, higher BMI was associated with higher odds of a diagnosed medical condition in 30 of 39 CDMCs, with all 30 displaying dose-response relationships. The 5 major CDMCs with the largest odds ratios comparing obese to normal weight were endocrine/nutritional/metabolic diseases (OR=2.67, 95%CI=2.24-3.15), nervous system diseases (odds ratio [OR]=2.59, 95%CI=2.32-2.90), circulatory system diseases (OR=2.56, 95%CI=2.15-3.06), musculoskeletal system diseases (OR=1.92, 95%CI=1.76-2.09), and mental/behavioral disorders (OR=1.69, 95%CI=1.51-1.90). Compared with normal weight SMs, overweight or obese SMs had a higher number of CDMCs (1.8±1.9 vs. 2.0±2.0 and 2.5±2.3, mean ± standard deviation, respectively, P<0.01).

CONCLUSIONS

In a young, physically active population, higher BMI was associated with a host of medical conditions, even after adjustment for demographic/lifestyle characteristics. The US Department of Defense should improve nutrition education and modify other factors that contribute to overweight and obesity. This study demonstrates that the medical burden of obesity is substantial in overweight and obese SMs.

Systematic review and meta-analysis: association between obesity/overweight and surgical complications in IBD

PURPOSE

While the prevalence of obesity in inflammatory bowel disease (IBD) patients is rapidly increasing, it is unclear whether obesity affects surgical outcomes in this population. This meta-analysis aims to assess the impact of obesity/overweight on patients undergoing surgery for IBD.

METHODS

Databases (PubMed, Web of Science, Cochrane Library, and Springer) were searched through September 2021. The meta-analysis included patients with surgically treated IBD to investigate the impact of obesity/overweight on this population. Primary outcomes included overall complications, infectious complications, noninfectious complications, and conversion to laparotomy.

RESULTS

Fifteen studies totaling 12,622 IBD patients were enrolled. Compared with nonobese (including overweight) patients, obese IBD patients have increased the risk in terms of overall complications (OR = 1.45, p < 0.001), infectious complications (OR = 1.48, p = 0.003) (especially wound complications), as well as conversion to laparotomy (OR = 1.90, p < 0.001). Among the noninfectious complications, only the incidence of visceral injury (OR = 2.36, p = 0.05) had significantly increased. Compared with non-overweight patients, the risk of developing wound complications (OR = 1.65, p = 0.01) and sepsis (OR = 1.73, p = 0.007) were increased in overweight patients, but the rates of overall complications (OR = 1.04, p = 0.81), infectious complications (OR = 1.31, p = 0.07), and conversion to laparotomy (OR = 1.33, p = 0.08) associated with body mass index (BMI) were not significantly different.

CONCLUSION

Obesity is a risk factor for surgical complications in IBD patients, mainly reflected in infectious complications. Moreover, obese patients seem to have a more common chance of developing surgical complications than overweight patients.

Functional and Phenotypic Characterization of B Cells in the Teleost Adipose Tissue

The immune response of the adipose tissue (AT) has been neglected in most animal models until investigations in human and mice linked obesity to chronic inflammation, highlighting the immune nature of this tissue. Despite this, in teleost fish, only a few studies have addressed the immune role of the AT. These studies have mostly focused on reporting transcriptional changes in the AT in response to diverse intraperitoneally delivered stimuli. Although the presence of B cells within the AT was also previously revealed, these cells have never been phenotypically or functionally characterized and this is what we have addressed in the current study. Initially, the B cell populations present in the rainbow trout (Oncorhynchus mykiss) AT were characterized in comparison to B cells from other sources. As occurs in other rainbow trout tissues, IgM⁺IgD⁺, IgM⁺IgD^- and IgD⁺IgM^- B cell subsets were identified in the AT. Interestingly, AT IgM⁺IgD^- B cells showed a transcriptional profile that agrees with that of cells that have committed to plasmablasts/plasma cells, being this profile much more pronounced towards a differentiation state than that of blood IgM⁺IgD^- B cells. Accordingly, the IgM-secreting capacity of AT B cells is significantly higher than that of blood B cells. Additionally, AT IgM⁺IgD⁺ B cells also showed specific phenotypic traits when compared to their counterparts in other tissues. Finally, we established how these B cell subsets responded when rainbow trout were intraperitoneally injected with a model antigen. Our results demonstrate that the AT hosts plasmablasts/plasma cells that secrete specific IgMs, as happens in the peritoneal cavity and systemic immune tissues. Although the presence of these antigen-specific IgM-secreting cells was more abundant in the peritoneal cavity, these specific differentiated B cells were detected in the AT for long time periods at levels similar to those of spleen and head kidney. Our results provide new evidence regarding the immune role of the teleost AT, indicating that it functions as a secondary lymphoid organ that promotes immunity to peritoneal antigens.

CIRCULATING GHRELIN LEVELS AND SUSCEPTIBILITY TO COLORECTAL CÂNCER

BACKGROUND AND OBJECTIVE

Considering the association between colorectal cancer (CRC) and both insulin resistance and obesity, and the prominent role of ghrelin in these metabolic disorders, we explored whether plasma levels of ghrelin were associated with CRC. Moreover, in the patients with CRC the possible correlations between ghrelin and insulin, insulin resistance, and body mass index (BMI) as an indicator of obesity were examined.

METHODS

A total of 170 subjects, including 82 cases with CRC and 88 controls were enrolled in this study. Plasma levels of ghrelin, insulin, and glucose were measured in all the subjects using ELISA and glucose oxidase methods. Furthermore, insulin resistance was assessed by calculating HOMA-IR index.

RESULTS

The cases with CRC had decreased ghrelin levels (P<0.001) and a higher HOMA-IR index (P<0.001) than controls. Interestingly, when CRC patients were stratified based on tumor site, lower ghrelin levels and a higher HOMA-IR index were observed in the patients with either colon or rectal cancer vs. controls too. Additionally, there were an age and BMI-independent negative correlation between ghrelin levels and HOMA-IR (r=-0.365, P<0.05), and an age-independent negative correlation between ghrelin levels and BMI (r=-0.335, P<0.05) in the rectal subgroup.

CONCLUSION

Our findings support a role for ghrelin in connection with insulin resistance and obesity in CRC susceptibility; however, it needs to be corroborated by further studies.

Body Composition Changes in Hepatocellular Carcinoma: Prediction of Survival to Transcatheter Arterial Chemoembolization in Combination With Clinical Prognostic Factors

Treatment-related toxicities and decreased levels of patient performance during cancer therapy might contribute to body composition changes (BCC) and thereby impact outcomes. This study investigated the association between BCC during transcatheter arterial chemoembolization (TACE) and outcome in patients with hepatocellular carcinoma (HCC), and developed a nomogram for predicting survival in combination with clinical prognostic factors (CPF). Pretreatment and posttreatment computed tomography (CT) images of 75 patients with HCC who were treated between 2015 and 2018 were analyzed. The bone mineral density (BMD), cross-sectional area of paraspinal muscles (CSA_muscle), subcutaneous fat area (SFA), and visceral fat area (VFA) were measured from two sets of CT images. Count the changes in body composition during treatment and sort out the CPF of patients. Using cox regression models, CSA_muscle change, SFA change, VFA change, child-push class, and portal vein thrombosis were independent prognostic factors for overall survival (OS) (HR=5.932, 2.384, 3.140, 1.744, 1.794, respectively. P < 0.05). Receiver operating characteristic curves (ROCs) showed the prediction model combination of BCC and CPF exhibited the highest predictive performance (AUC=0.937). Independent prognostic factors were all contained into the prognostic nomogram, the concordance index (C-index) of prognostic nomogram was 0.787 (95% CI, 0.675−0.887). Decision curve analysis (DCA) demonstrated that the prognostic nomogram was clinically useful. Nomogram-based risk classification systems were also constructed to facilitate risk stratification in HCC for optimization of clinical management. In conclusion, we identified CSA_muscle change, SFA change, VFA change, Child-Pugh class, and portal vein thrombosis were independent prognostic factors for HCC. The prognostic nomogram with a combination of BCC and CPF that can be applied in the individualized prediction of survival in patients with HCC after TACE.

Rising Rate of Obesity in Patients Admitted for Crohn's Disease Increases Costs But Not Mortality

GOAL

The goal of this study was to compare outcomes and trends for inpatients with Crohn's disease (CD) and obesity.

BACKGROUND

Obesity is a growing concern in the United States. Current data on the effect of obesity on the course of the CD are conflicted.

METHODS

Data from the 2016 to 2017 National Inpatient Sample were compared for obese, normal weight, and malnourished patients. After adjustment for comorbidities, demographics and disease type/inpatient surgery, outcomes including mortality, length of stay, hospitalization charges, and rates of deep venous thrombosis (DVT) in obese and malnourished patients were compared with those with normal body mass index using multivariable regression. For trend analysis, rates of obesity were compared from 2002 to 2017.

RESULTS

The percentage of patients with CD and obesity increased from 1.8% in 2002 to 9.5% in 2017 (0.5% per year, P<0.001). Rates of death were similar in obese versus normal-weight CD patients [odds ratio (OR)=1.21, 95% confidence interval (CI): 0.85-1.73, P=0.288]. In contrast, obese CD patients had increased length of stay (1.0 d, 95% CI: 0.81-1.26, P<0.001), cost ($8323, 95% CI: 5565-11,082, P<0.001), and DVT rate (OR=1.67, 95% CI: 1.13-2.46, P=0.01). Malnourished CD patients had OR for death of 2.15 (95% CI: 1.71-2.70, P<0.001) compared with normal-weight cohort. Similarly, length of stay, cost, and DVT rate were all increased.

CONCLUSIONS

Rates of hospitalized CD patients with obesity are increasing. Patients with obesity and CD have increased length of stay and costs, with no mortality difference. Malnourished CD patients continue to have higher mortality, length of stay, and cost. Obesity is a risk factor for adverse hospitalization outcomes.

Body Weight, Physical Activity, and Risk of Cancer in Lynch Syndrome

Lynch syndrome (LS) increases cancer risk. There is considerable individual variation in LS cancer occurrence, which may be moderated by lifestyle factors, such as body weight and physical activity (PA). The potential associations of lifestyle and cancer risk in LS are understudied. We conducted a retrospective study with cancer register data to investigate associations between body weight, PA, and cancer risk among Finnish LS carriers. The participants (n = 465, 54% women) self-reported their adulthood body weight and PA at 10-year intervals. Overall cancer risk and colorectal cancer (CRC) risk was analyzed separately for men and women with respect to longitudinal and near-term changes in body weight and PA using extended Cox regression models. The longitudinal weight change was associated with an increased risk of all cancers (HR 1.02, 95% CI 1.00-1.04) and CRC (HR 1.03, 1.01-1.05) in men. The near-term weight change was associated with a lower CRC risk in women (HR 0.96, 0.92-0.99). Furthermore, 77.6% of the participants retained their PA category over time. Men in the high-activity group had a reduced longitudinal cancer risk of 63% (HR 0.37, 0.15-0.98) compared to men in the low-activity group. PA in adulthood was not associated with cancer risk among women. These results emphasize the role of weight maintenance and high-intensity PA throughout the lifespan in cancer prevention, particularly in men with LS.

Insulin Resistance and Colorectal Cancer Risk: the Role of Elevated Plasma Resistin Levels

PURPOSE

Given the important role of resistin in insulin resistance (IR) and obesity, as well as the associations between both IR and obesity and increased risk of colorectal cancer (CRC), we investigated whether plasma resistin levels were associated with CRC risk. Furthermore, the possible correlations between resistin and insulin, IR, and obesity in patients with CRC and controls were explored.

METHODS

This study was conducted as a case-control study and 170 subjects, including 88 controls and 82 cases with CRC, were enrolled and their plasma levels of glucoe, insulin, and resistin were measured using glucose oxidase or ELISA methods. Moreover, IR was calculated according to HOMA-IR index.

RESULTS

The cases with CRC had a higher HOMA-IR than the controls (1.8 ± 0.4 versus 1.4 ± 0.3, P < 0.001). Additionally, after the stratification of the cases with CRC by tumor site, higher levels of resistin and insulin, and a higher HOMA-IR in the cases with rectal cancer than in the controls were observed (resistin 5.9 ± 1.2 versus 5.4 ± 1.3, P = 0.043; insulin 5.9 ± 1.2 versus 5.4 ± 1.3, P = 0.039; HOMA- IR 1.9 ± 0.4 versus 1.3 ± 0.3, P < 0.001). Furthermore, resistin was positively correlated with insulin in the controls (r = 0.737, P < 0.001), the cases with CRC (r = 0.881, P < 0.001), the cases with colon cancer (r = 0.811, P < 0.001), and the cases with rectal cancer (r = 0.990, P < 0.001). All these differences remained significant after adjustment for confounding factors.

CONCLUSIONS

The findings of the present study reinforce the hypothesis that higher plasma levels of resistin in connection with insulin resistance play a role in susceptibility to colorectal, notably rectal, cancer. Nevertheless, further studies with bigger sample sizes are required to validate these findings.

Obesity Is More Common in Children Newly Diagnosed With Ulcerative Colitis as Compared to Those With Crohn Disease

OBJECTIVE

This prospective observational study aimed to examine the prevalence of obesity in a population-based cohort of children and young adults newly diagnosed with inflammatory bowel disease (IBD) and assess their outcome in comparison to newly diagnosed normal/underweight patients.

METHODS

Our longitudinal population-based cohort comprised all children younger than 17 years diagnosed with IBD in the province of Manitoba, Canada between 2012 and 2018. Cox regression model with adjustment for a priori covariates was used to examine the time to first relapse among patients who were obese/overweight at the time of IBD diagnosis in comparison to patients who were normal or underweight.

RESULTS

A total of 139 patients with IBD were followed up for a median duration of 1.09 (interquartile range: 0.53-2.62) years. Obesity was more common in children newly diagnosed with ulcerative colitis (UC) compared to those with Crohn disease (CD) (12.7% vs 0.0%; P = 0.005). Age at diagnosis poorly correlated with the body mass index z score (R = 0.23; P = 0.01). The proportions of patients who were underweight at the time of IBD diagnosis among patients with UC and CD were 6.3% and 20.0%, respectively (P = 0.01). The time to initial relapse was not found to be significantly associated with weight category at diagnosis in UC (adjusted hazard ratio = 0.77; 95% confidence interval: 0.40-1.63) or CD (adjusted hazard ratio  = 0.83; 95% confidence interval: 0.20-3.51).

CONCLUSION

Obesity was more common in children and young adults newly diagnosed with UC. The majority of the underweight children had CD.

Body mass index and risk of inflammatory bowel disease: A systematic review and dose-response meta-analysis of cohort studies of over a million participants

The relationship between body mass index (BMI) and risk of inflammatory bowel disease (IBD) is controversial. We performed a dose-response meta-analysis to investigate the association between BMI and risk of incident ulcerative colitis (UC) and Crohn's disease (CD) using prospective cohort studies. A systematic search was conducted in MEDLINE/PubMed, SCOPUS, Cochrane, and Web of Science databases from inception to January 2019. DerSimonian and Laird random-effects model was used to estimate combined hazard ratios (HRs). Overall, 882 articles were screened, and 42 full-text articles were reviewed for inclusion using the study eligibility criteria. Five studies evaluated the association between BMI and IBD with 1 044 517 participants. Pooled results showed a significant association between participants affected by obesity and risk of CD (HR: 1.42, 95% CI: 1.18-1.71, I² : 0.00). There was a significant nonlinear association between BMI and risk of CD (P = .01, coeff = 0.5024). Pooled results did not show any significant association between being underweight and risk of UC (HR: 1.07, 95% CI: 0.96-1.19, I² : 0.00) or CD (HR: 1.11, 95% CI: 0.93-1.31, I² : 12.8). There was no difference in the risk for UC among participants affected by obesity compared with participants categorized as having normal BMI (HR: 0.96, 95% CI: 0.80-1.14, I² : 8.0). This systematic review and meta-analysis identified significant dose-response relationship between being affected by obesity, as a risk factor, and incidence of CD.

Effects of obesity and weight loss on mitochondrial structure and function and implications for colorectal cancer risk

Colorectal cancer (CRC) is the third most common cancer globally. CRC risk is increased by obesity, and by its lifestyle determinants notably physical inactivity and poor nutrition. Obesity results in increased inflammation and oxidative stress which cause genomic damage and contribute to mitochondrial dysregulation and CRC risk. The mitochondrial dysfunction associated with obesity includes abnormal mitochondrial size, morphology and reduced autophagy, mitochondrial biogenesis and expression of key mitochondrial regulators. Although there is strong evidence that increased adiposity increases CRC risk, evidence for the effects of intentional weight loss on CRC risk is much more limited. In model systems, energy depletion leads to enhanced mitochondrial integrity, capacity, function and biogenesis but the effects of obesity and weight loss on mitochondria in the human colon are not known. We are using weight loss following bariatric surgery to investigate the effects of altered adiposity on mitochondrial structure and function in human colonocytes. In summary, there is strong and consistent evidence in model systems and more limited evidence in human subjects that over-feeding and/or obesity result in mitochondrial dysfunction and that weight loss might mitigate or reverse some of these effects.

Metabolic status and lifestyle factors associated with gallbladder polyps: a covariance structure analysis

Background

Gallbladder Polyps (GBP) are highly prevalent in China; however, the etiology of GBP has not been clearly defined. This study explored the associations between lifestyle factors and GBP and whether it mediated by metabolic factors or not.

Methods

A total of 487 newly diagnosed GBP cases and 502 healthy controls were involved in this study. A questionnaire was used to investigate the socio-demographic characteristics and lifestyle factors. Food Intake Frequencies Questionnaire was used to obtain the food intake frequencies of seven food categories. Blood was tested for lipid profiles, fasting blood glucose and blood urine acid. A Covariance Structure Analysis was used in the analysis to explore the possible pathways between socio-demographic characteristics, lifestyle factors, metabolic factor and GBP.

Results

The Covariance Structure Analysis showed that a higher BMI and elevated triglyceride level mediated the association between age and GBP. Lifestyle factors (smoking and drinking) and higher intake frequencies of fatty food (meat and viscera) also linked to higher BMI and higher triglyceride level, respectively, which were associated with GBP.

Conclusion

In conclusion, age and lifestyle factors might be indirectly related with GBP through BMI and the triglyceride pathway.

Association between rs1862513 and rs3745367 Genetic Polymorphisms of Resistin and Risk of Cancer: A Meta-Analysis

The present study aimed to assess any associations between resistin gene (RETN) polymorphisms and cancer susceptibility by conducting a meta-analysis. A comprehensive literature search was performed with PubMed, Web of Science, Scopus and Google Scholar for relevant studies published before April 2018. For the rs1862513 polymorphism, data from 9 studies covering 1,951 cancer patients and 2,295 healthy controls were included in this meta-analysis. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Our meta-analysis revealed that this RETN polymorphism significantly increased the risk of cancer in codominant (OR=1.23, 95% CI= 1.01-1.50, p=0.04, CG vs CC; and OR=1.25, 95% CI= 1.03-1.53, p=0.03, GG vs CC), dominant (OR=1.19, 95% CI= 1.05-1.35, p=0.006, CG+GG vs CC), and allele (OR=1.14, 95% CI= 1.00-1.30, p=0.04, G vs C) inheritance genetic models. Stratification analysis by cancer type revealed that the rs1862513 variant significantly increased the risk of colorectal and breast cancer, and that cancer overall in Caucasians (OR=1.22, 95% CI= 1.04-1.43, p=0.02, CG+GG vs CC; OR=1.18, 95% CI= 1.04-1.34, p=0.01, G vs C). The data revealed no correlation between the rs3745367 polymorphism and cancer risk. Further well-designed studies with larger sample sizes and different ethnicities are warranted to validate the present findings.

Colonic diverticulosis and the metabolic syndrome: an association?

BACKGROUND AND OBJECTIVES

Colonic diverticulosis (CD) is related to advanced age and a lack of dietary fiber. Recently, several studies have shown that metabolic syndrome (MS) is also implicated in the etiopathogenesis of CD. This study aimed to assess the association between MS, obesity and CD.

METHODS

This was a prospective study of a one-year duration. The MS was defined according to the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III). Demographic data, risk factors for MS and endoscopic findings of patients who underwent a total colonoscopy in the department were collected. Obesity was defined as a body mass index ≥ 30 kg/m2. Informed consent was obtained. The local Ethics Committee and National Data Protection Committee approved the study. Statistical analysis was performed with SPSS 21 and statistical significance was defined as p < 0.05.

RESULTS

The study included 203 patients, 95 males with a mean age of 65.5 years. CD was diagnosed in 30.5% of patients. Univariate analysis showed that age, hypertension, increased waist circumference and hyperlipidemia were associated with colonic diverticulosis. There was no association with gender, obesity or type 2 diabetes mellitus. Multivariate analysis showed that age and a greater waist circumference increased the risk of diverticulosis. Age-adjusted analysis showed that MS was associated with diverticulosis. The prevalence of adenoma in patients with CD was similar to that in patients without CD.

CONCLUSION

In this series, MS was significantly associated with CD. The identification of risk groups is important since diverticulosis can have serious and potentially fatal complications. To our knowledge, this is the first Southern European prospective study evaluating the association between MS and CD.

Height and body fatness and colorectal cancer risk: an update of the WCRF-AICR systematic review of published prospective studies

PURPOSE

There is no published dose-response meta-analysis on the association between height and colorectal cancer risk (CRC) by sex and anatomical sub-site. We conducted a meta-analysis of prospective studies on the association between height and CRC risk with subgroup analysis and updated evidence on the association between body fatness and CRC risk.

METHODS

PubMed and several other databases were searched up to November 2016. A random effects model was used to calculate dose-response summary relative risks (RR's).

RESULTS

47 studies were included in the meta-analyses including 50,936 cases among 7,393,510 participants. The findings support the existing evidence regarding a positive association of height, general and abdominal body fatness and CRC risk. The summary RR were 1.04 [95% (CI)1.02-1.05, I² = 91%] per 5 cm increase in height, 1.02 [95% (CI)1.01-1.02, I² = 0%] per 5 kg increase in weight, 1.06 [95% (CI)1.04-1.07, I² = 83%] per 5 kg/m2 increase in BMI, 1.02 [95% (CI)1.02-1.03, I² = 4%] per 10 cm increase in waist circumference, 1.03 [95% (CI)1.01-1.05, I² = 16%] per 0.1 unit increase in waist to hip ratio. The significant association for height and CRC risk was similar in men and women. The significant association for BMI and CRC risk was stronger in men than in women.

CONCLUSION

The positive association between height and risk of CRC suggests that life factors during childhood and early adulthood might play a role in CRC aetiology. Higher general and abdominal body fatness during adulthood are risk factors of CRC and these associations are stronger in men than in women.

Visceral obesity as a risk factor for colorectal adenoma occurrence in surveillance colonoscopy

BACKGROUND AND AIMS

The aim of this study was to examine the prospective association between visceral obesity and the incidence and recurrence of colorectal adenoma.

METHODS

We conducted a cohort study involving 2244 participants between 2006 and 2007. The study participants were prospectively followed until 2014 according to the initial colonoscopy and histopathology findings. Incident and recurrent colorectal adenoma groups were defined as individuals with a positive follow-up colonoscopy result from the normal results and adenoma groups, respectively, at the baseline colonoscopy.

RESULTS

Among the 1163 patients (51.8%) who received a follow-up colonoscopy, 509 (43.8%) and 654 (56.2%) were grouped into the normal and adenoma cohorts. Colorectal adenomas occurred in 592 patients (50.9%) during the median period of 43 months, with an incident adenoma prevalence of 39.1% and a recurrent adenoma prevalence of 60.1%. An increase in the visceral adipose tissue (VAT) area was associated with a higher incidence of adenoma (highest quintile vs lowest quintile of the VAT hazard ratios [HRs], 2.16; 95% confidence interval [CI], 1.26-3.71; HR 1.32 [per 1-standard deviation]; 95% CI, 1.10-1.60) in the multivariable analysis. Increases in body mass index and waist circumference were associated with recurrent adenomas (HR 1.33 [per 1 kg/m²], 95% CI, 1.18-1.46; HR 1.04 [per 1 cm], 95% CI, 1.01-1.07, respectively) in the multivariate analysis.

CONCLUSION

A higher VAT area was dose-dependently associated with a higher risk of incident adenoma. Furthermore, increases in body mass index and waist circumference as surrogate markers of abdominal obesity were associated with a higher risk of recurrent adenoma.

High and low body mass index may predict severe disease course in children with inflammatory bowel disease

OBJECTIVES

Inflammatory bowel disease (IBD) has been historically associated with underweight and malnutrition. The impact of both underweight and obesity on the clinical course of IBD in adults is controversial. This study described the association between body mass index (BMI) at diagnosis to disease course in children with IBD.

METHODS

We reviewed the medical records of children with IBD from the database of the 'Dana-Dwek' Children's Hospital between 2010 and 2016. Demographic and anthropometric data were collected as were disease characteristics, course and therapy. Patients were categorized in quartiles according to BMI percentiles at diagnosis (Q1-Q4).

RESULTS

Of 100 children who were identified, 62 had Crohn's disease (CD) and 38 had ulcerative colitis (UC). The median age (interquartile range, IQR) at diagnosis was 13.7 (range 11.9-15.2) years. The median (IQR) follow-up was 2.1 (1.2-3.8) years. At diagnosis, 46 children (46%) were in Q1, 20 (20%) in Q2, 19 (19%) in Q3 and 15 (15%) in Q4. Prolonged time to diagnosis was associated with BMI in Q1 and Q4, as well as high disease activity at diagnosis (p < .001). In a multivariate analysis, BMI in the lower and upper quartiles was associated with disease exacerbation (HR 3.212 and 4.651, respectively, p = .016) and anti-tumor necrosis factor (TNF) therapy (HR 4.489 and 3.972, respectively, p = .021).

CONCLUSIONS

BMI in the lower and upper quartiles was associated with more severe disease course in children with IBD. BMI may serve as a simple and highly accessible predictor of pediatric IBD course and prognosis.

The effect of metabolic syndrome on postoperative outcomes following laparoscopic colectomy

BACKGROUND

Among the criteria used to diagnose metabolic syndrome (MS), obesity and diabetes mellitus (DM) are associated with poor postoperative outcomes following colectomy. MS is also associated with colorectal cancer (CRC) and diverticulosis, both of which may be treated with colectomy. However, the effect of MS on postoperative outcomes following laparoscopic colectomy has yet to be clarified.

METHODS

In an academic tertiary hospital, data from all consecutive patients undergoing laparoscopic colectomy from 2005 to 2014 were prospectively recorded and analysed. Patients presenting with MS [defined by the presence of three or more of the following criteria: elevated blood pressure, body mass index > 28 kg/m², dyslipidemia (decreased serum HDL cholesterol, increased serum triglycerides) and increased fasting glucose/DM] were compared with patients without MS regarding peri-operative outcome [mainly anastomotic leaks, severe postoperative complications (Clavien-Dindo III and IV)] and mortality.

RESULTS

Overall, 1236 patients were included: 508 (41.1%) right colectomies and 728 (58.9%) left colectomies. Seven hundred seventy-two (62.4%) of these procedures were performed for CRC. MS was diagnosed in 85 (6.9%) patients, who were significantly older than the others (70 vs. 64.2 years, p < 0.001), and presented with more cardiac comorbidities (p < 0.001). MS was associated with increased blood loss (122.5 vs. 79.9 mL p = 0.001) and blood transfusion requirement (5.9 vs. 1.7%, p = 0.021). The anastomotic leak rate was 6.6% (with 2.2% of anastomotic leaks requiring surgical treatment), and the overall reoperation rate was 6.9%. The incidence of severe postoperative complications was 11.5%, and the overall mortality rate 0.6%. No differences were found between the groups in overall postoperative morbidity and mortality. Median length of stay was similar in both groups (7 days).

CONCLUSIONS

MS does not jeopardize postoperative outcomes following laparoscopic colectomy.

The longitudinal association between changes in lung function and changes in abdominal visceral obesity in Korean non-smokers

Obesity, particularly abdominal obesity, might be related to decreased lung function. We aimed to investigate whether obesity indices are associated with forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in asymptomatic non-smokers through a longitudinal cohort study. The clinical records of 1,145 subjects (428 males, mean age 52.3 years) who underwent a comprehensive health evaluation, including spirometry and abdominal fat computed tomography, at least twice between 2007 and 2014 were retrospectively reviewed and analysed. The mean follow-up period was 1,105 days (over 3.0 years). The baseline total adipose tissue (TAT) and visceral adipose tissue (VAT) were inversely associated with both FEV1 and FVC (P < 0.05). The longitudinal study found that increasing TAT and VAT were significantly related to decreasing FEV1 and FVC, whereas decreasing TAT and VAT were related to increasing FEV1 and FVC in both males and females (P < 0.05). The strength and consistency of these associations were clearer in males than in females. However, no significant relationship was found between changes in subcutaneous adipose tissue and changes in lung function. In Korean non-smokers, longitudinal changes in abdominal visceral fat were found to be inversely related to changes in lung function over a mean period of three years. These results suggest that decreasing abdominal visceral obesity could increase lung function despite ageing.

Relation of body mass index to risk of developing inflammatory bowel disease amongst women in the Danish National Birth Cohort

BACKGROUND

Crohn's disease (CD) has traditionally been associated with weight loss and low BMI, yet paradoxically obesity has recently been suggested as a risk factor for CD, but not for ulcerative colitis (UC). We therefore hypothesized that the relation between BMI and CD is U shaped.

AIM

To conduct a large population-based prospective cohort study of BMI and later risk of IBD, taking age at IBD diagnosis into account.

METHODS

A cohort of 74,512 women from the Danish National Birth Cohort, with BMI measured pre-pregnancy and 18 months after delivery, was followed for 1,022,250 person-years for development of IBD, according to the Danish National Patient Register. Associations were tested by Cox regression.

RESULTS

Overweight subjects (25≤BMI<30 kg/m2) had the lowest risk of CD, whereas obesity (BMI≥30kg/m2) increased the risk of CD at all ages, and low BMI (BMI<18.5kg/m2) associated with CD diagnosed at age 18-<40 years. Hence, using normal weight subjects as the reference, adjusted HRs for risk of developing CD (at age 18-<40 years) were 1.8(95%CI, 0.9-3.7) for underweight, 0.6(0.3-1.2) for overweight, and 1.5(0.8-2.7) for obese individuals (pre-pregnancy BMI). HRs were greater for BMI determined 18 months after delivery. Splines for CD risk according to waist:height ratio confirmed a U-shaped relationship with CD occurring <40 years, and a linear relationship with CD diagnosed at age 40+. There was no relationship between BMI and risk of UC.

CONCLUSION

For the first time, we demonstrate that both high BMI and low BMI are risk factors for CD. Underweight may be a pre-clinical manifestation of disease being present many years before onset with obesity being a true risk factor. This raises the question as to whether there may be two distinct forms of CD.

Protective effects of polyphenol-rich infusions from carob (Ceratonia siliqua) leaves and cladodes of Opuntia ficus-indica against inflammation associated with diet-induced obesity and DSS-induced colitis in Swiss mice

In the present study, we have investigated the effects of polyphenol-rich infusions from carob leaves and OFI-cladodes on inflammation associated with obesity and dextran sulfate sodium (DSS)-induced ulcerative colitis in Swiss mice. In vitro studies revealed that aqueous extracts of carob leaves and OFI-cladodes exhibited anti-inflammatory properties marked by the inhibition of IL-6, TNF-α and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells concomitant with NF-κβ nucleus translocation inhibition. For in vivo investigations, Swiss male mice were subjected to control or high fat diet (HFD). At the 8th week after the start of study, animals received or not 1% infusion of either carob leaves or OFI-cladode for 4 weeks and were subjected to 2% DSS administration in drinking water over last 7 days. After sacrifice, pro-inflammatory cytokines levels in plasma and their mRNA expression in different organs were determined. Results showed that carob leaf and OFI-cladode infusions reduced inflammation severity associated with HFD-induced obesity and DSS-induced acute colitis indicated by decrease in pro-inflammatory cytokines expression (as such TNF-α, IL1b and IL-6) in colon, adipose tissue and spleen. In addition, plasma levels of IL-6 and TNF-α were also curtailed in response to infusions treatment. Thus, carob leaf and OFI-cladode infusions prevented intestinal permeability through the restoration of tight junction proteins (Zo1, occludins) and immune homeostasis. Hence, the anti-inflammatory effect of carob leaves and OFI-cladodes could be attributed to their polyphenols which might alleviate inflammation severity associated with obesity and colitis.

Adipose Tissue Inflammation Induces B Cell Inflammation and Decreases B Cell Function in Aging

Aging is the greatest risk factor for developing chronic diseases. Inflamm-aging, the age-related increase in low-grade chronic inflammation, may be a common link in age-related diseases. This review summarizes recent published data on potential cellular and molecular mechanisms of the age-related increase in inflammation, and how these contribute to decreased humoral immune responses in aged mice and humans. Briefly, we cover how aging and related inflammation decrease antibody responses in mice and humans, and how obesity contributes to the mechanisms for aging through increased inflammation. We also report data in the literature showing adipose tissue infiltration with immune cells and how these cells are recruited and contribute to local and systemic inflammation. We show that several types of immune cells infiltrate the adipose tissue and these include macrophages, neutrophils, NK cells, innate lymphoid cells, eosinophils, T cells, B1, and B2 cells. Our main focus is how the adipose tissue affects immune responses, in particular B cell responses and antibody production. The role of leptin in generating inflammation and decreased B cell responses is also discussed. We report data published by us and by other groups showing that the adipose tissue generates pro-inflammatory B cell subsets which induce pro-inflammatory T cells, promote insulin resistance, and secrete pathogenic autoimmune antibodies.

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.

Body mass index greater than 35 is associated with severe Clostridium difficile infection

BACKGROUND

Obesity has been implicated in the acquisition of Clostridium difficile infections (CDI), however, no study has investigated whether there is a correlation between body mass index (BMI) and CDI severity.

AIM

To determine whether obesity, as measured by BMI correlates with severe hospital-onset or community-onset CDI.

METHODS

Patients admitted with CDI at a tertiary-care center from January 2013 to June 2015 were identified. The cohort was stratified by onset of disease using the National Healthcare Safety Network criteria, and by severity using the 2013 American College of Gastroenterology guidelines. Multivariate logistic regression was used to determine independent predictors of severe CDI.

RESULTS

A total of 196 met the inclusion criteria, of which 57.1% (112) met criteria for severe disease. Overall, BMI >35 kg/m² was 1.7-fold more likely to be associated with severe CDI compared to a BMI 20-35 kg/m² (P < 0.005), and was an independent predictor of severe CDI (P = 0.038). In patients with community-onset-CDI and hospital-onset-CDI, a BMI >35 kg/m² was associated with a 1.96-fold and 1.48 greater rate of severe CDI compared to a BMI 20-35 kg/m² (P = 0.004 and 0.048), and was an independent predictor of severe CDI in these cohorts (P = 0.039 and 0.027) respectively.

CONCLUSION

This study has identified an association between body mass index and Clostridium difficile infection severity. A BMI>35 kg/m² is an independent risk factor for severe community-onset and hospital-onset Clostridium difficile infections.

Visceral Obesity Is Associated with Gallbladder Polyps

Background/Aims

Gallbladder polyps (GBP) are a common clinical finding and may possess malignant potential. We conducted this study to determine whether visceral obesity is a risk factor for GBP.

Methods

We retrospectively reviewed records of subjects who received both ultrasonography and computed tomography with measurements of the areas of visceral adipose tissue and total adipose tissue (TAT) on the same day as health checkups.

Results

Ninety-three of 1,615 subjects (5.8%) had GBP and were compared with 186 age- and sex-matched controls. VAT (odds ratio [OR], 2.941; 95% confidence interval [CI], 1.325 to 6.529; p=0.008 for the highest quartile vs the lowest quartile) and TAT (OR, 3.568; 95% CI, 1.625 to 7.833; p=0.002 for the highest quartile vs the lowest quartile) were independent risk factors together with hypertension (OR, 2.512; 95% CI, 1.381 to 4.569; p=0.003), diabetes mellitus (OR, 2.942; 95% CI, 1.061 to 8.158; p=0.038), hepatitis B virus positivity (OR, 3.548; 95% CI, 1.295 to 9.716; p=0.014), and a higher level of total cholesterol (OR, 2.232; 95% CI, 1.043 to 4.778; p=0.039 for <200 mg/dL vs ≥240 mg/dL). Body mass index and waist circumference were not meaningful variables.

Conclusions

Visceral obesity measured by VAT and TAT was associated with GBP irrespective of body mass index or waist circumference.

Gly972Arg variant of insulin receptor substrate 1 gene and colorectal cancer risk in overweight/obese subjects

BACKGROUND

Given the major role of obesity and insulin resistance (IR) in colorectal cancer (CRC), we investigated whether genetic variants in ghrelin (GHRL), resistin (RETN) and insulin receptor substrate 1 (IRS1) were associated with CRC risk.

METHODS

This study was conducted as a case-control study, and 750 subjects, including 438 controls and 312 patients with CRC, were enrolled and genotyped using the PCR-RFLP method.

RESULTS

No significant differences were observed for GHRL (rs696217), RETN (rs3745367) and IRS1 (rs1801278, Gly972Arg or G972R) gene variants between the cases and controls. However, the IRS1 G972R R allele compared with the G allele and the G972R RR+GR genotype compared with the GG genotype appeared to be markers of decreased CRC susceptibility in the overweight/obese subjects (p = 0.024; odds ratio [OR] = 0.42, 95% confidence interval [95% CI], 0.20-0.91; and p = 0.048; OR = 0.42, 95% CI, 0.17-0.99, respectively). Furthermore, the R allele and RR+GR genotype were also associated with decreased risks for obesity in the patients with CRC (p = 0.007; OR = 0.35, 95% CI, 0.15-0.77; and p = 0.015; OR = 0.35, 95% CI, 0.15-0.72, respectively).

CONCLUSIONS

In accordance with previous studies, our findings suggest that the IRS1 G972R R allele and RR+GR genotype have protective effects for CRC in overweight/obese patients and for obesity in patients with CRC. Nevertheless, further studies are required to confirm these findings.

Inhibitory Effects of 4'-Demethylnobiletin, a Metabolite of Nobiletin, on 12-O-Tetradecanoylphorbol-13-acetate (TPA)-Induced Inflammation in Mouse Ears

Nobiletin (NOB) is major citrus flavonoid with many health-promoting benefits. We reported previously that 4'-demethylnobiletin (4DN), a major metabolite of NOB, significantly inhibited lipopolysaccharide (LPS)-stimulated inflammation in RAW 264.7 macrophages. In this study, we further studied the anti-inflammatory effects of 4DN in TPA-induced skin inflammation in mice. We demonstrated that topical application of 4DN decreased TPA-induced ear edema by >88 ± 4.77% in mice. This inhibitory effect was associated with inhibition on TPA-induced up-regulation of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. Immunoblotting results showed that 4DN resulted in profound effects on multiple proteins related with inflammation and carcinogenesis. 4DN significantly decreased the expression levels of iNOS, COX-2, and MMP-9, suppressed phosphorylation of PI3K/Akt and ERK, and increased the levels of HO-1 and NQO1 in TPA-treated mice. Overall, the results demonstrated that 4DN had strong anti-inflammatory effects in vivo, which provided a scientific basis for using NOB to inhibit inflammation-driven diseases.

Impact of Obesity on the Management and Clinical Course of Patients with Inflammatory Bowel Disease

BACKGROUND

Obesity has been linked with a proinflammatory state and the development of inflammatory diseases. Data on the clinical course and treatment of obese patients with inflammatory bowel disease (IBD) are limited. We used an institutional IBD registry to investigate the impact of obesity on IBD severity and treatment.

METHODS

This was a retrospective analysis of prospectively collected data for 3 years (2009-2011). Patients with IBD were categorized by body mass index (BMI). IBD-related quality of life, biochemical markers of inflammation, comorbidities, health care utilization, and treatment were characterized. Obesity was defined as a BMI ≥30 (type I: 30-34.9, type II: 35-39.9, and type III ≥40).

RESULTS

Among 1494 patients with IBD, 71.9% were above their ideal BMI and 31.5% were obese. Obesity was more common in ulcerative colitis compared with patients with Crohn's disease (P = 0.04). Obese class II and class III patients were predominantly female. Obesity in IBD was associated with female gender (P < 0.0001), diabetes mellitus (P < 0.001), hypertension (P < 0.001), hyperlipidemia (P < 0.001), poor quality of life (P < 0.0001), and increased rates of C-reactive protein elevation (P = 0.008). In logistic regression analysis, quality of life and C-reactive protein elevation were not independently correlated with obesity. There was no association between increasing BMI and annual prednisone use, emergency department visits, hospitalization, and surgery. Obesity was associated with lower milligrams per kilogram doses of purine analogs and biologics.

CONCLUSIONS

Obesity in IBD is not associated with increased health care utilization and IBD-related surgeries. Optimal regimens for drug dosing in obese patients with IBD have yet to be defined.

Gallstone disease and obesity: a population-based study on abdominal fat distribution and gender differences

BACKGROUND

Existing evidence suggests the visceral fat is more metabolically active than subcutaneous fat. We aimed to investigate the value of subcutaneous (SAT) and visceral adipose tissue thickness (VAT) for prediction of gallstone disease (GSD) in general population by focus on gender differences and comparison with body mass index (BMI), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR).

MATERIAL AND METHODS

In this cross-sectional survey, 1,494 subjects (51.4 % men), aged above 50, randomly selected from Golestan Cohort Study residing in Gonbad City, Iran, underwent anthropometric measurements and abdominal ultrasonography.

RESULTS

Prevalence of GSD was 17.8% (95% CI 15.9-19.8). Following adjustment for age and then other potential risk factors, all obesity indices, except for SAT, were associated with GSD in women with the highest odds ratio observed in WHtR (OR 1.52, 95% CI 1.22-1.89). In contrast, WHR was the only associated index in men (OR 1.49, 95% CI 1.08-2.06). The trend of increasing obesity measures across the quartiles with the risk of GSD was significant in subgroups of WHtR and BMI in women and WHR in men. No significant association was found between SAT and GSD in men or women.

CONCLUSIONS

The best anthropometric indicators of the risk of GSD may differ by gender. In men, WHR might be the only preferred index to estimate risk of GSD. WHtR, WHR, VAT and BMI are associated with GSD risk in women, although WHtR might better explain this risk. SAT is the poor indicator for identifying subjects with GSD in both genders.

Colorectal adenoma is associated with coronary artery calcification in a Korean population

OBJECTIVE

Colorectal adenoma and coronary atherosclerosis have similar risk factors. The aim of this study was to investigate the association between colorectal adenoma and coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis.

METHODS

This is a cross-sectional study of 398 Koreans (290 males, mean age of 56.8 ± 8.1 years) who underwent CAC scoring by multi-slice computed tomography and colonoscopy on the same day as the screening examination. The CAC scores were divided into the following three categories according to severity: absent (CAC score = 0), mild (0 < CAC score ≤ 100), and moderate-to-severe CAC (CAC score > 100).

RESULTS

Colorectal adenoma was detected in 149 (37.4%) subjects and was significantly associated with a CAC score of >0 (OR = 1.66, 95% CI = 1.05-2.64, P = 0.032), including both mild (OR = 1.80, 95% CI = 1.06-3.03, P = 0.029) and moderate-to-severe CAC (OR = 1.95, 95% CI = 1.05-3.63, P = 0.035), in multivariate analysis after adjusting for age, gender and other risk factors. The proportion of subjects with colorectal adenoma and advanced adenoma progressively increased with increasing CAC score (colorectal adenoma 28.9%-54.1%, P for trend < 0.001; advanced adenoma 7.0%-16.4%, P for trend = 0.026).

CONCLUSION

Colorectal adenoma is related to coronary artery calcification independent of traditional risk factors for asymptomatic Koreans. The prevalence of advanced adenoma is more common in individuals with severe coronary atherosclerosis.

Obesity-related insulin resistance: implications for the surgical patient

In healthy surgical patients, preoperative fasting and major surgery induce development of insulin resistance (IR). IR can be present in up to 41% of obese patients without diabetes and this can rise in the postoperative period, leading to an increased risk of postoperative complications. Inflammation is implicated in the aetiology of IR. This review examines obesity-associated IR and its implications for the surgical patient. Searches of the Medline and Science Citation Index databases were performed using various key words in combinations with the Boolean operators AND, OR and NOT. Key journals, nutrition and metabolism textbooks and the reference lists of key articles were also hand searched. Adipose tissue has been identified as an active endocrine organ and the chemokines secreted as a result of macrophage infiltration have a role in the pathogenesis of IR. Visceral adipose tissue appears to be the most metabolically active, although results across studies are not consistent. Results from animal and human studies often provide conflicting results, which has rendered the pursuit of a common mechanistic pathway challenging. Obesity-associated IR appears, in part, to be related to inflammatory changes associated with increased adiposity. Postoperatively, the surgical patient is in a proinflammatory state, so this finding has important implications for the obese surgical patient.

Comparing the effect of visceral fat and barley seed ash (hordeum vulgare L) with silversulfadiazine on burn wound healing in rats

BACKGROUND

Skin burn is one of the most common complications and remains a major public health issue worldwide.

OBJECTIVES

This experiment was conducted to study the effects of traditional medicine (Visceral Fat and Barely Seed Ash) compared with silversulfadiazine (SSD) cream on healing burn wounds in rats.

MATERIALS AND METHODS

Sixty adult male Wistar rats were randomly divided into four groups of equal numbers; each group consisted of 15 animals. After sedation, type II of skin burn with 1.5 cm diameter circle was created on the back of rats with a heated metal in boiling water. Group one was not treated and considered as control. The burned areas in the second, third and fourth groups were applied twice a day with normal saline, SSD cream and traditional preparation, respectively. Percentage of the burn wound concentration and histopathological examinations were used as parameters of our study on days 4, 9and 14. Obtained data were compared between the groups and days.

RESULTS

SSD cream and traditional preparation had better effects on burnt wound healing compared with control group. Furthermore, on the final day of study, the average percentage of wound concentration in traditional medicine group was significantly greater than other groups (P < 0.05). This finding was supported and confirmed by histological examination as well.

CONCLUSIONS

Traditional preparation significantly decreased inflammation and accelerated wound healing in treated rats. Furthermore, the findings of this study can be applied clinically in the future.

The effect of body weight on the severity and clinical course of ulcerative colitis

PURPOSE

Obesity is a risk factor for inflammatory diseases such as nonalcoholic steatohepatitis, pancreatitis, and Crohn's disease. The effect of being overweight or obese on the severity and clinical course of ulcerative colitis (UC) was assessed in a retrospective analysis of data from 2000-2006.

METHODS

Two hundred and two consecutive UC patients were categorized according to body mass index (BMI). Patient and disease characteristics were compared between BMI categories using chi-square or Kruskal-Wallis tests. The percentage of patients with active UC, complications, steroid therapy, or immunosuppressive therapy was calculated for each group, and matched pair analyses were performed.

RESULTS

Ten patients (5%) were underweight, 111 (55%) were normal weight, 54 (26.7%) were overweight, and 27 (13.4%) were obese. Pancolitis was inversely related to weight. BMI was also inversely correlated to disease severity, with a significantly smaller proportion of years with chronic active disease among overweight subjects versus normal-weight subjects (17.6 versus 23.9%, p = 0.05). More overweight than normal-weight patients had no chronic active disease in any year (66 versus 49%, p = 0.06), and the proportion of years with disease complications was higher in normal weight than in overweight subjects (1.8 versus 0.4%, p = 0.08). Disease activity during 2000-2006 was higher for underweight versus normal-weight patients, and only 20% of underweight subjects had no hospital admission compared to 80% of normal-weight patients (p = 0.07).

CONCLUSIONS

This first study to explore the influence of obesity on UC showed that high BMI had rather a favorable effect on the prognosis, whereas low BMI pointed to a more severe course of the disease.

Metabolic inflammation in inflammatory bowel disease: crosstalk between adipose tissue and bowel

Epidemiological studies show that both the incidence of inflammatory bowel disease (IBD) and the proportion of people with obesity and/or obesity-associated metabolic syndrome increased markedly in developed countries during the past half century. Obesity is also associated with the development of more active IBD and requirement for hospitalization and with a decrease in the time span between diagnosis and surgery. Patients with IBD, especially Crohn's disease, present fat-wrapping or "creeping fat," which corresponds to ectopic adipose tissue extending from the mesenteric attachment and covering the majority of the small and large intestinal surface. Mesenteric adipose tissue in patients with IBD presents several morphological and functional alterations, e.g., it is more infiltrated with immune cells such as macrophages and T cells. All these lines of evidence clearly show an association between obesity, adipose tissue, and functional bowel disorders. In this review, we will show that the mesenteric adipose tissue and creeping fat are not innocent by standers but actively contribute to the intestinal and systemic inflammatory responses in patients with IBD. More specifically, we will review evidence showing that adipose tissue in IBD is associated with major alterations in the secretion of cytokines and adipokines involved in inflammatory process, in adipose tissue mesenchymal stem cells and adipogenesis, and in the interaction between adipose tissue and other intestinal components (immune, lymphatic, neuroendocrine, and intestinal epithelial systems). Collectively, these studies underline the importance of adipose tissue for the identification of novel therapeutic approaches for IBD.

Protracted upregulation of leptin and IGF1 is associated with activation of PI3K/Akt and JAK2 pathway in mouse intestine after ionizing radiation exposure

Ionizing radiation is a known risk factor for gastrointestinal (GI) pathologies including cancer. Hormones and related signaling crosstalk, which could contribute to radiation-induced persistent pathophysiologic changes in the small intestine and colon, remain to be explored. The current study assessed perturbation of GI homeostasis-related hormones and signaling pathways at the systemic as well as at the tissue level in small intestine and colon. Mice (6-8 week old C57BL/6J) were exposed to 2 Gy γ radiation, serum and tissue samples were collected, and insulin like growth factor 1 (IGF-1) and leptin signaling were assessed two or twelve months after radiation exposure. Serum levels of IGF-1, IGF binding protein 3 (IGFBP3), leptin, and adiponectin were altered at these times after irradiation. Radiation was associated with increased IGF1 receptor (IGF1R) and obesity (leptin) receptor (Ob-R), decreased adiponectin receptor 1 (Adipo-R1) and 2 (Adipo-R2), and increased Ki-67 levels in small intestine and colon at both time points. Immunoblot analysis further showed increased IGF1R and Ob-R, and decreased Adipo-R2. Additionally, upregulation of PI3K/Akt and JAK2 signaling, which are downstream of IGF1 and leptin, was also observed in irradiated samples at both time points. These results when considered along with increased cell proliferation in the small intestine and colon demonstrate for the first time that ionizing radiation can persistently increase IGF1 and leptin and activate downstream proliferative pathways, which may contribute to GI functional alterations and carcinogenesis.

Diet and colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common diagnosed cancer in men and the second in women. Dietary factors and lifestyle may contribute to the increasing CRC incidence, making these issues interesting for both the general population and the medical oncology community.

OBJECTIVE

The aim of this report is to present a review of the published epidemiologic research to date reflecting the most current scientific evidence related to diet and CRC risk.

DESIGN

EMBASE and PubMed-NCBI were searched for relevant articles up to November 2014 that identified potential interactions between foods or dietary patterns and CRC risk.

RESULTS

Obesity increases the risk of CRC by 19%. Regular physical activity reduces this risk by 24%. CRC risk derived from red meat intake is influenced by both total intake and its frequency. Fish consumption may decrease CRC risk by 12% whereas garlic intake is not significantly associated with reduced CRC risk. Intakes of more than 20g/day of fiber are associated with a 25% reduction of CRC risk and 525mL/day of milk reduces colon cancer risk by 26% in men. Moderate amounts of alcohol (25-30g/day) increase CRC risk.

CONCLUSIONS

CRC is a preventable disease through the modification of associated risk factors, including physical inactivity, obesity and overweight, excessive meat intake, smoking and alcoholic beverage consumption. Nonetheless, epidemiological evidence in this regard is not conclusive so further research is warranted.

Impact of abdominal visceral adipose tissue on disease outcome in pediatric Crohn's disease

BACKGROUND

Increased abdominal visceral adipose tissue (VAT) is associated with systemic inflammation. The influence of VAT on pediatric inflammatory bowel disease (IBD) has not been studied. The objective of this study was to investigate the differences in VAT between pediatric patients with IBD and age-matched controls and identify associations between VAT and Crohn's disease (CD) outcomes.

METHODS

Single-center retrospective cohort study of 114 pediatric patients with IBD (101 CD and 13 ulcerative colitis) who had abdominal computed tomography at diagnosis. VAT volumes were measured from computed tomography images. A control group of 78 age-matched patients without IBD who had abdominal computed tomography was selected for comparison.

RESULTS

Median VAT was 634 cm (interquartile range, 411-1041) in the IBD group and 659 cm (interquartile range, 394-1015) in the controls. IBD group had 33% higher VAT than controls (95% confidence interval [CI], 11-58) P = 0.002 after adjusting for body mass index and age. In patients with CD, higher VAT was associated with fistulizing or fibrostenotic disease (odds ratio [OR], 1.7; 95% CI, 1.1-2.9; P = 0.03), CD hospitalizations (OR, 1.9; 95% CI, 1.2-3.4; P = 0.01), moderate or severe disease activity scores (OR, 1.8; 95% CI, 1.1-3.1; P = 0.02), and shorter intervals from diagnosis to surgery (hazard ratio, 1.4; 95% CI, 1.0-2.0; P = 0.05) after adjusting for body mass index and age.

CONCLUSIONS

At diagnosis, pediatric patients with IBD have higher adjusted VAT volumes than age- and body mass index-matched controls. Higher VAT volumes in pediatric patients with CD predicted more hospitalizations, increased likelihood of complicated disease, shorter interval from diagnosis to surgery, and higher disease activity scores at diagnosis.

Immunological characterization of the teleost adipose tissue and its modulation in response to viral infection and fat-content in the diet

The immune response of the adipose tissue (AT) has been neglected in most animal models until recently, when the observations made in human and mice linking obesity to chronic inflammation and diabetes highlighted an important immune component of this tissue. In the current study, we have immunologically characterized the AT for the first time in teleosts. We have analyzed the capacity of rainbow trout (Oncorhynchus mykiss) AT to produce different immune mediators and we have identified the presence of local populations of B lymphocytes expressing IgM, IgD or IgT, CD8α⁺ cells and cells expressing major histocompatibility complex II (MHC-II). Because trout AT retained antigens from the peritoneal cavity, we analyzed the effects of intraperitoneal infection with viral hemorrhagic septicemia virus (VHSV) on AT functionality. A wide range of secreted immune factors were modulated within the AT in response to VHSV. Furthermore, the viral infection provoked a significant decrease in the number of IgM⁺ cells which, along with an increased secretion of IgM in the tissue, suggested a differentiation of B cells into plasmablasts. The virus also increased the number of CD8α⁺ cells in the AT. Finally, when a fat-enriched diet was fed to the fish, a significant modulation of immune gene expression in the AT was also observed. Thus, we have demonstrated for the first time in teleost that the AT functions as a relevant immune tissue; responsive to peritoneal viral infections and that this immune response can be modulated by the fat-content in the diet.

Resistin -420C>G promoter variant and colorectal cancer risk

PURPOSES

Obesity is associated with an increased risk of colorectal cancer (CRC), and ghrelin (GHRL) and resistin (RETN) are thought to be related to obesity. Our aim was to investigate whether GHRL and RETN gene variants are associated with CRC risk.

MATERIALS AND METHODS

All 414 subjects, including 197 cases with CRC and 217 controls, were genotyped for the GHRL (rs26802) and RETN (rs1862513) or -420 C>G gene variants using the PCR-RFLP method.

RESULTS

Our findings indicated that the RETN -420 C>G "CC" genotype, compared with the "GG" and "GC" genotypes, was a marker of decreased CRC susceptibility; the difference remained significant after adjustment for age, BMI, gender, smoking status, NSAID use, and family history of CRC (p=0.020; OR=0.52, 95% CI=0.30-0.90). Furthermore, after adjustment for confounding factors, the -420 C>G "CC" genotype, compared with the "GG" genotype, was associated with a decreased risk for CRC (p=0.044; OR=0.53, 95% CI=0.29-0.98). In addition, no significant difference was observed for the GHRL (rs26802) gene variant.

CONCLUSIONS

To our knowledge, this is the first study suggesting that the RETN -420 C>G "CC" genotype is a marker of decreased CRC susceptibility. This observation is relevant from a scientific perspective and deserves further investigations.

Single anastomosis or mini-gastric bypass: long-term results and quality of life after a 5-year follow-up

BACKGROUND

Laparoscopic mini-gastric bypass (LMGB) is an alternative to the laparoscopic Roux-en-Y gastric bypass (LRYGB), which is considered to be the gold standard in the treatment of morbid obesity.

OBJECTIVES

Present 5-year results of 175 patients who had undergone a LMGB between October 2006 and October 2008.

SETTING

University public hospital, France.

METHODS

Complete follow-up was available in 126 of 175 patients (72%) who had LMGB. Mortality, morbidity, weight loss, co-morbidities, and quality of life were assessed. Weight loss was determined as a change in body mass index (BMI) and percent excess BMI loss (%EBMIL). Quality of life in the treatment group was analyzed using the Gastrointestinal Quality of Life Index (GIQLI) and was compared with a retrospectively case matched preoperative control group.

RESULTS

There were no deaths. Thirteen patients (10.3%) developed major complications. Marginal ulcers occurred in 4% of patients. Incapacitating biliary reflux developed in 2 (1.6%) who required conversion into RYGB. Gastric pouch dilation occurred in 4 patients (3.2%) and inadequate weight loss with severe malnutrition in 2 (1.6%). At 5 years, mean BMI was 31±6 kg/m(2) and mean %EBMIL was 71.5%±26.5%. Postoperative GIQLI score of the treatment group was significantly higher than preoperative score of the control group (110.3±17.4 versus 92.5±15.9, P<.001). Social, psychological, and physical functions were increased significantly. No significant differences were found in gastroesophageal reflux or diarrhea symptoms between the 2 groups. Long-term follow-up showed an improvement in all co-morbidities.

CONCLUSIONS

At 5 years, LMGB was safe, effective, and provided interesting quality of life results.

Metabolomics of ApcMin/+ mice genetically susceptible to intestinal cancer

Background

To determine how diets high in saturated fat could increase polyp formation in the mouse model of intestinal neoplasia, Apc^Min/+, we conducted large-scale metabolome analysis and association study of colon and small intestine polyp formation from plasma and liver samples of Apc^Min/+ vs. wild-type littermates, kept on low vs. high-fat diet. Label-free mass spectrometry was used to quantify untargeted plasma and acyl-CoA liver compounds, respectively. Differences in contrasts of interest were analyzed statistically by unsupervised and supervised modeling approaches, namely Principal Component Analysis and Linear Model of analysis of variance. Correlation between plasma metabolite concentrations and polyp numbers was analyzed with a zero-inflated Generalized Linear Model.

Results

Plasma metabolome in parallel to promotion of tumor development comprises a clearly distinct profile in Apc^Min/+ mice vs. wild type littermates, which is further altered by high-fat diet. Further, functional metabolomics pathway and network analyses in Apc^Min/+ mice on high-fat diet revealed associations between polyp formation and plasma metabolic compounds including those involved in amino-acids metabolism as well as nicotinamide and hippuric acid metabolic pathways. Finally, we also show changes in liver acyl-CoA profiles, which may result from a combination of Apc^Min/+-mediated tumor progression and high fat diet. The biological significance of these findings is discussed in the context of intestinal cancer progression.

Conclusions

These studies show that high-throughput metabolomics combined with appropriate statistical modeling and large scale functional approaches can be used to monitor and infer changes and interactions in the metabolome and genome of the host under controlled experimental conditions. Further these studies demonstrate the impact of diet on metabolic pathways and its relation to intestinal cancer progression. Based on our results, metabolic signatures and metabolic pathways of polyposis and intestinal carcinoma have been identified, which may serve as useful targets for the development of therapeutic interventions.