Association of low serum adiponectin levels with erosive esophagitis in men: an analysis of 2405 subjects undergoing physical check-ups

Novel insights into the pathogenic impact of diabetes on the gastrointestinal tract

Type 2 and type 1 diabetes are common endocrine disorders with a progressively increasing incidence worldwide. These chronic, systemic diseases have multiorgan implications, and the whole gastrointestinal (GI) tract represents a frequent target in terms of symptom appearance and interdependent pathophysiological mechanisms. Metabolic alterations linked with diabetic complications, neuropathy and disrupted hormone homeostasis can lead to upper and/or lower GI symptoms in up to 75% of diabetic patients, with multifactorial involvement of the oesophagus, stomach, upper and lower intestine, and of the gallbladder. On the other hand, altered gastrointestinal motility and/or secretions are able to affect glucose and lipid homeostasis in the short and long term. Finally, diabetes has been linked with increased cancer risk at different levels of the GI tract. The presence of GI symptoms and a comprehensive assessment of GI function should be carefully considered in the management of diabetic patients to avoid further complications and to ameliorate the quality of life. Additionally, the presence of gastrointestinal dysfunction should be adequately managed to improve metabolic homeostasis, the efficacy of antidiabetic treatments and secondary prevention strategies.

Role of Obesity, Physical Exercise, Adipose Tissue-Skeletal Muscle Crosstalk and Molecular Advances in Barrett's Esophagus and Esophageal Adenocarcinoma

Both obesity and esophageal adenocarcinoma (EAC) rates have increased sharply in the United States and Western Europe in recent years. EAC is a classic example of obesity-related cancer where the risk of EAC increases with increasing body mass index. Pathologically altered visceral fat in obesity appears to play a key role in this process. Visceral obesity may promote EAC by directly affecting gastroesophageal reflux disease and Barrett’s esophagus (BE), as well as a less reflux-dependent effect, including the release of pro-inflammatory adipokines and insulin resistance. Deregulation of adipokine production, such as the shift to an increased amount of leptin relative to “protective” adiponectin, has been implicated in the pathogenesis of BE and EAC. This review discusses not only the epidemiology and pathophysiology of obesity in BE and EAC, but also molecular alterations at the level of mRNA and proteins associated with these esophageal pathologies and the potential role of adipokines and myokines in these disorders. Particular attention is given to discussing the possible crosstalk of adipokines and myokines during exercise. It is concluded that lifestyle interventions to increase regular physical activity could be helpful as a promising strategy for preventing the development of BE and EAC.

Abdominal obesity increases the risk of reflux esophagitis: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

The association between abdominal obesity and reflux esophagitis (RE) has been extensively evaluated, but the current findings are mixed and more convincing epidemiological evidence urgently needs to be established. To thoroughly explore this relationship, we summarized the latest studies, performed an updated meta-analysis, and examined the dose-response relationship.

METHODS

We performed a systematic search of PubMed, Web of Science, and Embase up to 28 March 2021, using prespecified terms to identify studies investigating the association between abdominal obesity and RE. Odds ratios (ORs) with 95% confidence intervals (CIs), mean differences (MDs) or standardized mean differences (SMDs) with 95% CIs were taken as effect-size estimates.

RESULTS

Forty-two observational studies, including 11 cohort studies, were meta-analyzed. Overall, a statistically significant association was observed between abdominal obesity and RE, by both the pooled OR (adjusted OR = 1.51, 95% CI: 1.37-1.66, p < .001) and the pooled SMD (SMD = 0.36, 95% CI: 0.30-0.42, p < .001). Moreover, this significant relationship persisted with subgroup stratification. In subgroup analyses, we found that study design, abdominal obesity measurement, adjustment for covariates and sex were possible sources of between-study heterogeneity. For the dose-response analyses, the risk of RE increased with the degree of abdominal obesity, and the increasing trend accelerated when waist circumference (WC) reached 87.0 cm.

CONCLUSION

This meta-analysis indicated a significant association between abdominal obesity and RE, and the risk of RE increased with abdominal obesity especially when the WC was over 87.0 cm.

Visceral fat obesity is the key risk factor for the development of reflux erosive esophagitis in 40-69-years subjects

BACKGROUND

Visceral fat obesity can be defined quantitatively by abdominal computed tomography, however, the usefulness of measuring visceral fat area to assess the etiology of gastrointestinal reflux disease has not been fully elucidated.

METHODS

A total of 433 healthy subjects aged 40-69 years (234 men, 199 women) were included in the study. The relationship between obesity-related factors (total fat area, visceral fat area, subcutaneous fat area, waist circumference, and body mass index) and the incidence of reflux erosive esophagitis was investigated. Lifestyle factors and stomach conditions relevant to the onset of erosive esophagitis were also analyzed.

RESULTS

The prevalence of reflux erosive esophagitis was 27.2% (118/433; 106 men, 12 women). Visceral fat area was higher in subjects with erosive esophagitis than in those without (116.6 cm² vs. 64.9 cm², respectively). The incidence of erosive esophagitis was higher in subjects with visceral fat obesity (visceral fat area ≥ 100 cm²) than in those without (61.2% vs. 12.8%, respectively). Visceral fat obesity had the highest odds ratio (OR) among obesity-related factors. Multivariate analysis showed that visceral fat area was associated with the incidence of erosive esophagitis (OR = 2.18), indicating that it is an independent risk factor for erosive esophagitis. In addition, daily alcohol intake (OR = 1.54), gastric atrophy open type (OR = 0.29), and never-smoking history (OR = 0.49) were also independently associated with the development of erosive esophagitis.

CONCLUSIONS

Visceral fat obesity is the key risk factor for the development of reflux erosive esophagitis in subjects aged 40-69 years.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

Potential involvement of adiponectin in obesity-associated erosive esophagitis

A strong causal relationship between obesity and erosive esophagitis has been proposed. Obesity may affect the pathogenesis of erosive esophagitis through adipokines as well as acid reflux. We evaluated the involvement of adiponectin in obesity-associated erosive esophagitis. In total, 1,902 patients who underwent endoscopy during medical check-ups were selected for study. Variables including the body mass index (BMI) and adiponectin level were compared between subjects with erosive esophagitis and normal controls. The subjects were classified by quartiles (Qs) of adiponectin level. Q4 was the reference group. The median adiponectin level differed by gender (men, 5.3 µg/ml vs women, 9.3 µg/ml; p<0.001). As the severity of erosive esophagitis increased in men, the BMI increased (p<0.001) while the adiponectin level decreased (p = 0.026). The multivariate odds ratio for erosive esophagitis was 1.79 for Q1, 1.73 for Q2, 2.34 for obesity, and 27.40 for hiatal hernia in men. When classified by obesity, the multivariate odds ratio for erosive esophagitis was 1.94 for Q1, 2.10 for Q2, and 18.47 for hiatal hernia only in obese men. In women, there were no trends in BMI, adiponectin levels, or severity of erosive esophagitis. We demonstrated that low adiponectin levels are involved in obesity-associated erosive esophagitis in men but not women.

Statins and gastroesophageal reflux disease: A meta-analysis

Background/Objectives

Gastroesophageal reflux disease (GERD) is one of the common gastrointestinal disorders worldwide. Recent epidemiologic studies have suggested that use of statins may lower the risk of GERD although the results from different studies were inconsistent. This systematic review and meta-analysis were conducted with the aim to summarize all available data.

Methods

A systematic literature review was performed using MEDLINE and EMBASE database from inception to December 2017. Cohort, case-control, and cross-sectional studies that compared the risk of GERD among statin users versus nonusers were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

Results

A total of 4 studies (1 case control, 1 cohort, and 2 cross-sectional studies) with 14,505 participants met the eligibility criteria and were included in the meta-analysis. The risk of GERD among statin users was numerically lower than nonusers with the pooled OR of 0.89 but the result did not achieve statistical significance (95% CI, 0.60-1.33). The statistical heterogeneity in this study was moderate (I² = 54%).

Conclusions

The current meta-analysis found that the risk of GERD was numerically lower among statin users although the pooled result did not reach statistical significance. Therefore, more studies are still needed to further clarify this potential benefit of statins.

Adiponectin level changes among Egyptians with gastroesophageal reflux disease

Background and Aim

Visceral fat is an important endocrine organ that secretes different bioactive substances such as adipocytokines. The aim of this study was to investigate the adiponectin level changes among patients with erosive gastroesophageal reflux disease (GERD)and its consequence on pathogenesis.

Methods

In this study, 150 subjects were selected and divided into four groups: Group І (n = 40) were healthy individuals with an average body mass index and had no gastrointestinal tract symptoms; Group ІІ (n = 50) were patients with mild to moderate erosive esophagitis; Group ІІІ (n = 40) were patients with severe erosive esophagitis; and finally, Group ІV (n = 20) were patients with Barrett's esophagus. Upper gastrointestinal endoscopy was performed for Groups II, III, and IV only, and histopathological assessment was conducted for the suspicious cases of Barrett's esophagus. The measurement of serum adiponectin was performed for all groups using the ELISA test.

Results

Our results revealed that the serum level of adiponectin was significantly lower in patients with different grades of GERD as well Barrett's esophagus as compared to healthy controls (P‐value < 0.001). Additionally, the serum level of adiponectin was correlated with different grades of GERD as the highest level of the adiponectin was found in the control group (11.05 ± 2.58) followed by mild to moderate GERD (6.39 ± 1.64) and then severe GERD (2.42 ± 1.00); finally, the lowest level was detected in the Barrett's esophagus group (1.99 ± 0.47). Our study showed significant correlation between body mass index, waist circumference, and waist–hip ratio on one hand and serum adiponectin level on the other hand, with a statistically significant difference (P‐value < 0.001). The best cut‐off value for serum adiponectin was 7.7 (μg/mL), with a sensitivity of 91.8% and specificity of 97.5%.

Conclusions

Low serum adiponectin level appears to be associated with an increased risk of erosive esophagitis, and visceral fat accumulation is related to the impaired secretion of adiponectin, which may have an influence on the pathogenesis of GERD.

Age and sex differences in serum adiponectin and its association with lipoprotein fractions

Objective The correlation of adiponectin with cholesterol concentration of fractionated lipoproteins has not been well investigated. Methods This study included 174 subjects (79 men and 95 women) without diabetes. The medical record data were investigated retrospectively. The study subjects with adiponectin <8.3, > 8.3 but less 13.9, and ≥ 13.9 were classified into tertile groups: Groups A ( n = 59), B ( n = 58) and C ( n = 57), respectively. Results In women, age and HDL-C were higher in Group C than in Groups A and B, but BMI, TG, IDL-C and VLDL-C were lower in Group C than in Groups A and B. In men, BMI was lower in Group C than in Groups A and B, and HDL-C was higher in Group C than in Groups A and B. In multiple stepwise regression analysis, BMI and HDL-C were significantly correlated with adiponectin in whole, male and female subjects, but TG-rich lipoprotein cholesterol concentrations were not independently correlated. Conclusions HDL-C and BMI were independently correlated with adiponectin in non-diabetic men and women. These results suggest that high adiponectin may play a role in the increased HDL-C concentrations, implicated in the reduction of cardiovascular disease risk, in non-diabetic subjects.

Is Metabolic Syndrome Considered to Be a Risk Factor for Gastroesophageal Reflux Disease (Non-Erosive or Erosive Esophagitis)?: A Systematic Review of the Evidence

CONTEXT

The incidences of both gastroesophageal reflux disease (GERD) and metabolic syndrome (MetS) have increased in recent years, and it has been suggested that there is a probable association between the two. The aim of this review is to clarify whether or not MetS is a risk factor for the incidence of GERD.

EVIDENCE AQUISITION

We searched the PubMed, ProQuest, Ovid, Science Direct, and Google Scholar databases up to February 2015 regarding the relationship between GERD and MetS as found in observational studies. Any studies that evaluated the association between the components of MetS and GERD, as well as any studies examining the association of MetS with Barrett's esophagus or esophageal carcinoma, were excluded.

RESULTS

Thirteen studies met the eligibility criteria. The results of nine studies suggested that there was a higher prevalence of MetS among patients with GERD (P < 0.05) and, thus, it could be considered as an independent risk factor for the incidence of GERD. However, in the one study was not observed significant association between GERD and MetS (P = 0.71). Two studies in which the prevalence of GERD was compared between individuals with and without MetS showed a higher prevalence of GERD in patients with MetS (P < 0.05). However, this finding was not observed in a similar study conducted among female participants, which reported that the different types of MetS were not important factors with regard to the prevalence of erosive esophagitis (P = Not significant).

CONCLUSIONS

It can be concluded that MetS may increase the risk of GERD. Consequently, there might be potential benefits to treating the metabolic abnormalities in these patients.

Association of medications for lifestyle-related diseases with reflux esophagitis

BACKGROUND

Because of a change in lifestyle, especially adoption of westernized eating habits, lifestyle-related diseases have become increasingly prevalent. The aim of this study was to investigate the association of medications for lifestyle-related diseases with reflux esophagitis (RE).

METHODS

We conducted a hospital-based, cross-sectional retrospective study of consecutive outpatients who received an upper gastrointestinal endoscopy in our department from February 2008 to November 2014, which was performed by one specialist who was a member of the Japan Gastroenterological Endoscopy Society. We investigated the patient profile, Helicobacter pylori (H. pylori) infection status, medications for lifestyle-related diseases (including calcium channel blockers, statins, and bisphosphonates), and upper gastrointestinal endoscopic findings (RE, hiatal hernia, Barrett's mucosa, and endoscopic gastric mucosal atrophy [EGA]). Patients with gastrectomy, peptic ulcer disease, gastric or esophageal malignant disease, and those who used proton pump inhibitors or histamine-2 receptor antagonists were excluded. We divided the subjects into a group without RE (RE(-)) and a RE (RE(+)) group as judged by endoscopy, and investigated the risk factors for RE.

RESULTS

Of 1,744 consecutive cases, 590 cases (300 males and 290 females; mean age 60.5±13.2 years) were eligible. RE(-) and RE(+) cases numbered 507 and 83, respectively. Bivariate analysis showed significant positive associations of RE with male sex, body mass index (BMI), calcium channel blockers, Barrett's mucosa, hiatal hernia and negative associations of RE with H. pylori positivity, EGA. Multivariate analysis showed significant positive associations of RE with BMI (odds ratio [OR]: 1.20, 95% confidence interval [95% CI]: 1.10-1.29), use of calcium channel blockers (OR: 2.12, 95% CI: 1.16-3.87), Barrett's mucosa (OR: 2.97, 95% CI: 01.64-5.38), hiatal hernia (OR: 3.13, 95% CI: 1.79-5.47) and negative associations of RE with H. pylori positivity (OR: 0.20, 95% CI: 0.07-0.57), use of statins (OR: 0.42, 95% CI: 0.18-0.96), and EGA (OR: 0.83, 95% CI: 0.70-0.98).

CONCLUSION

Calcium channel blockers were positively associated with RE and statins were negatively associated with RE, while bisphosphonates were not associated with RE.

Impact of obesity treatment on gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a frequently encountered disorder. Obesity is an important risk factor for GERD, and there are several pathophysiologic mechanisms linking the two conditions. For obese patients with GERD, much of the treatment effort is focused on weight loss and its consistent benefit to symptoms, while there is a relative lack of evidence regarding outcomes after novel or even standard medical therapy is offered to this population. Physicians are hesitant to recommend operative anti-reflux therapy to obese patients due to the potentially higher risks and decreased efficacy, and these patients instead are often considered for bariatric surgery. Bariatric surgical approaches are broadening, and each technique has emerging evidence regarding its effect on both the risk and outcome of GERD. Furthermore, combined anti-reflux and bariatric options are now being offered to obese patients with GERD. However, currently Roux-en-Y gastric bypass remains the most effective surgical treatment option in this population, due to its consistent benefits in both weight loss and GERD itself. This article aims to review the impact of both conservative and aggressive approaches of obesity treatment on GERD.

Advantages and disadvantages of technologies for HER2 testing in breast cancer specimens

OBJECTIVES

Human epidermal growth factor receptor 2 (HER2) plays a central role as a prognostic and predictive marker in breast cancer specimens. Reliable HER2 evaluation is central to determine the eligibility of patients with breast cancer to targeted anti-HER2 therapies such as trastuzumab and lapatinib. Presently, several methods exist for the determination of HER2 status at different levels (protein, RNA, and DNA level).

METHODS

In this review, we discuss the main advantages and disadvantages of the techniques developed so far for the evaluation of HER2 status in breast cancer specimens.

RESULTS

Each technique has its own advantages and disadvantages. It is therefore not surprising that no consensus has been reached so far on which technique is the best for the determination of HER2 status.

CONCLUSIONS

Currently, emphasis must be put on standardization of procedures, internal and external quality control assessment, and competency evaluation of already existing methods to ensure accurate, reliable, and clinically meaningful test results. Development of new robust and accurate diagnostic assays should also be encouraged. In addition, large clinical trials are warranted to identify the technique that most reliably predicts a positive response to anti-HER2 drugs.

Associations of Circulating Gut Hormone and Adipocytokine Levels with the Spectrum of Gastroesophageal Reflux Disease

OBJECTIVE

The pathogenesis of gastroesophageal reflux disease (GERD) is complex and poorly understood. We aim to investigate the association of various circulating peptide hormones with heterogenous manifestations of GERD.

METHODS

One hundred and four patients that had experienced typical GERD symptoms (heartburn and/or acid regurgitation) for at least 3 episodes per week in the past 3 months were enrolled. All patients received a baseline assessment of symptom severity and frequency with the Reflux Disease Questionnaire and an upper endoscopy to classify GERD into erosive esophagitis (EE, n = 67), non-erosive esophagitis (NE, n = 37), and Barrett's esophagus (BE, n = 8). Fifty asymptomatic subjects with an endoscopically normal esophagus were recruited as the control group. Complete anthropometric measures and blood biochemistry were obtained and fasting serum levels of adipocytokines (adiponectin and leptin) and gut hormones (ghrelin and peptide YY (PYY)) were determined by enzyme-linked immunosorbent assay in all subjects.

RESULTS

All circulating peptide hormone levels were not statistically different between the GERD and control groups. However, GERD patients appeared to have lower PYY levels [median (25th-75th percentile), 80.1 (49.8-108.3) vs. 99.4 (65.8-131.9) pg/ml, p = 0.057] compared with control subjects. Among the GERD patients, ghrelin levels were inversely associated with the frequency and severity of acid regurgitation. In male GERD patients, EE was associated with significantly higher PYY levels [107.0 (55.0-120.8) vs. 32.8 (28.7-84.5) pg/ml, p = 0.026] but lower adiponectin levels [6.7 (5.6-9.3) vs. 9.9 (9.6-10.6) μg/ml, p = 0.034] than NE. Patients with BE had significantly lower adiponectin levels [6.0 (5.1-9.2) vs. 9.2 (7.1-11.2) μg/ml, p = 0.026] than those without BE.

CONCLUSIONS

Humoral derangement of circulating peptide hormones might participate in inflammation and symptom perception in patients suffering from GERD. Further studies to clarify the exact role of these hormones in the pathogenesis of GERD are warranted.

Association of Visceral Fat Area, Smoking, and Alcohol Consumption with Reflux Esophagitis and Barrett's Esophagus in Japan

BACKGROUND

Central obesity has been suggested as a risk factor for gastroesophageal reflux disease. The aim of this study was to evaluate the association of visceral fat area and other lifestyle factors with reflux esophagitis or Barrett's esophagus in Japanese population.

METHODS

Individuals who received thorough medical examinations including the measurement of visceral fat area by abdominal computed tomography were enrolled. Factors associated with the presence of reflux esophagitis, the severity of reflux esophagitis, or the presence of Barrett's esophagus were determined using multivariable logistic regression models.

RESULTS

A total of 2608 individuals were eligible for the analyses. Visceral fat area was associated with the presence of reflux esophagitis both in men (odds ratio, 1.21 per 50 cm2; 95% confident interval, 1.01 to 1.46) and women (odds ratio, 2.31 per 50 cm2; 95% confident interval, 1.57 to 3.40). Current smoking and serum levels of triglyceride were also associated with the presence of reflux esophagitis in men. However, significant association between visceral fat area and the severity of reflux esophagitis or the presence of Barrett's esophagus was not shown. In men, excessive alcohol consumption on a drinking day, but not the frequency of alcohol drinking, was associated with both the severity of reflux esophagitis (odds ratio, 2.13; 95% confident interval, 1.03 to 4.41) and the presence of Barrett's esophagus (odds ratio, 1.71; 95% confident interval, 1.14 to 2.56).

CONCLUSION

Visceral fat area was independently associated with the presence of reflux esophagitis, but not with the presence of Barrett's esophagus. On the other hand, quantity of alcohol consumption could play a role in the development of severe reflux esophagitis and Barrett's esophagus in Japanese population.

Gastrointestinal symptoms in morbid obesity

Background: Several reports have shown an increased prevalence of gastrointestinal (GI) symptoms in obese subjects in community-based studies. To better understand the role of the GI tract in obesity, and because there are limited clinic-based studies, we documented the prevalence of upper and lower GI symptoms in morbidly obese individuals in a clinic setting.

Objective: The aim of our study was to compare the prevalence of GI symptoms in morbidly obese individuals in a weight management clinic with non-obese individuals with similar comorbidities as morbidly obese individuals in an Internal Medicine clinic.

Methods: Class II and III obese patients BMI >35 kg/m² (N = 114) and 182 non-obese patients (BMI <25 kg/m²) completed the GI symptoms survey between August 2011 and April 2012 were included in this study. The survey included 24 items pertaining to upper and lower GI symptoms. The participants rated the frequency of symptoms as absent (never, rarely) or present (occasionally, frequently). The symptoms were clustered into five categories: oral symptoms, dysphagia, gastroesophageal reflux, abdominal pain, and bowel habits. Responses to each symptom cluster were compared between obese group and normal weight groups using logistic regression.

Results: Of the 24 items, 18 had a higher frequency in the obese group (p < 0.005 for each). After adjusting for age and gender, the obese patients were more likely to have upper GI symptoms: any oral symptom (OR = 2.3, p = 0.0013), dysphagia (OR 2.9, p = 0.0006), and any gastroesophageal reflux (OR 3.8, p < 0.0001). Similarly, the obese patients were more likely to have lower GI symptoms: any abdominal pain (OR = 1.7, p = 0.042) and altered bowel habits (OR = 2.8, p < 0.0001).

Conclusion: These observations suggest a statistically significant increase in frequency of both upper and lower GI symptoms in morbidly obese patients when compared to non-obese subjects.

Pathophysiological mechanisms linking obesity and esophageal adenocarcinoma

In recent decades there has been a dramatic rise in the incidence of esophageal adenocarcinoma (EAC) in the developed world. Over approximately the same period there has also been an increase in the prevalence of obesity. Obesity, especially visceral obesity, is an important independent risk factor for the development of gastro-esophageal reflux disease, Barrett's esophagus and EAC. Although the simplest explanation is that this mediated by the mechanical effects of abdominal obesity promoting gastro-esophageal reflux, the epidemiological data suggest that the EAC-promoting effects are independent of reflux. Several, not mutually exclusive, mechanisms have been implicated, which may have different effects at various points along the reflux-Barrett's-cancer pathway. These mechanisms include a reduction in the prevalence of Helicobacter pylori infection enhancing gastric acidity and possibly appetite by increasing gastric ghrelin secretion, induction of both low-grade systemic inflammation by factors secreted by adipose tissue and the metabolic syndrome with insulin-resistance. Obesity is associated with enhanced secretion of leptin and decreased secretion of adiponectin from adipose tissue and both increased leptin and decreased adiponectin have been shown to be independent risk factors for progression to EAC. Leptin and adiponectin have a set of mutually antagonistic actions on Barrett's cells which appear to influence the progression of malignant behaviour. At present no drugs are of proven benefit to prevent obesity associated EAC. Roux-en-Y reconstruction is the preferred bariatric surgical option for weight loss in patients with reflux. Statins and aspirin may have chemopreventative effects and are indicated for their circulatory benefits.

The role of obesity in oesophageal cancer development

The incidence of oesophageal adenocarcinoma has increased dramatically in the developed world in the last half century. Over approximately the same period there has been an increase in the prevalence of obesity. Multiple epidemiological studies and meta-analyses have confirmed that obesity, especially abdominal, visceral obesity, is a risk factor for gastro-oesophageal reflux, Barrett's oesophagus and oesophageal adenocarcinoma. Although visceral obesity enhances gastro-oesophageal reflux, the available data also show that visceral obesity increases the risk of Barrett's oesophagus and adenocarcinoma via reflux-independent mechanisms. Several possible mechanisms could link obesity with the risk of oesophageal adenocarcinoma in addition to mechanical effects increasing reflux. These include reduced gastric Helicobacter pylori infection, altered intestinal microbiome, factors related to lifestyle, the metabolic syndrome and associated low-grade inflammation induced by obesity and the secretion of mediators by adipocytes which may directly influence the oesophageal epithelium. Of these adipocyte-derived mediators, increased leptin levels have been independently associated with progression to oesophageal adenocarcinoma and in laboratory studies leptin enhances malignant behaviours in cell lines. Adiponectin is also secreted by adipocytes and levels decline with obesity: decreased serum adiponectin levels are associated with malignant progression in Barrett's oesophagus and experimentally adiponectin exerts anticancer effects in Barrett's cell lines and inhibits growth factor signalling. At present there are no proven chemopreventative interventions that may reduce the incidence of obesity-associated oesophageal cancer: observational studies suggest that the combined use of a statin and aspirin or another cyclo-oxygenase inhibitor is associated with a significantly reduced cancer incidence in patients with Barrett's oesophagus.

Adiponectin inhibits murine pancreatic cancer growth

BACKGROUND

Adiponectin is an adipose tissue-derived secretory hormone whose plasma concentrations are lower in obese individuals. Obesity is a risk factor for the development and growth of pancreatic cancer, and hypoadiponectinemia was suggested to be involved in the growth of Pan02 murine pancreatic cancer cells that were inoculated into the flanks of congenitally obese mice.

AIM

The aim of this study was to clarify the role of adiponectin in the growth of pancreatic cancer cells.

METHODS

We examined the effect of adiponectin on the growth of Pan02 cells using recombinant adiponectin and adiponectin knockout mice.

RESULTS

The in vitro treatment of Pan02 cells with adiponectin inhibited cellular proliferation that was accompanied by increased apoptosis and caspase-3 and caspase-7 activities. Transplantation of Pan02 cells into the pancreas of knockout mice resulted in a larger tumor volume with fewer terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positive cells compared with wild-type mice.

CONCLUSIONS

The results indicate that adiponectin directly suppresses the proliferation of Pan02 cells.

Adiponectin inhibits leptin-induced oncogenic signalling in oesophageal cancer cells by activation of PTP1B

Obesity is characterised by hyperleptinaemia and hypoadiponectinaemia and these metabolic abnormalities may contribute to the progression of several obesity-associated cancers including oesophageal adenocarcinoma (OAC). We have examined the effects of leptin and adiponectin on OE33 OAC cells. Leptin stimulated proliferation, invasion and migration and inhibited apoptosis in a STAT3-dependant manner. Leptin-stimulated MMP-2 secretion in a partly STAT3-dependent manner and MMP-9 secretion via a STAT3-independent pathway. Adiponectin inhibited leptin-induced proliferation, migration, invasion, MMP secretion and reduced the anti-apoptotic effects: these effects of adiponectin were ameliorated by both a non-specific tyrosine phosphatase inhibitor and a specific PTP1B inhibitor. Adiponectin reduced leptin-stimulated JAK2 activation and STAT3 transcriptional activity in a PTP1B-sensitive manner and adiponectin increased both PTP1B protein and activity. We conclude that adiponectin restrains leptin-induced signalling and pro-carcinogenic behaviour by inhibiting the early events in leptin-induced signal transduction by activating PTP1B. Relative adiponectin deficiency in obesity may contribute to the promotion of OAC.

Adiponectin as a routine clinical biomarker

Adiponectin is a protein synthesized and secreted predominantly by adipocytes into the peripheral blood. However, circulating adiponectin level is inversely related with body weight, especially visceral fat accumulation. The mechanism of this paradoxical relation remains obscure. Low circulating adiponectin concentrations (hypoadiponectinemia; <4 μg/mL) are associated with a variety of diseases, including dysmetabolism (type 2 diabetes, insulin resistance, hypertension, dyslipidemia, metabolic syndrome, hyperuricemia), atherosclerosis (coronary artery disease, stroke, peripheral artery disease), sleep apnea, non-alcoholic fatty liver disease, gastritis and gastro-esophageal reflux disease, inflammatory bowel diseases, pancreatitis, osteoporosis, and cancer (endometrial cancer, postmenopausal breast cancer, leukemia, colon cancer, gastric cancer, prostate cancer). On the other hand, hyperadiponectinemia is associated with cardiac, renal and pulmonary diseases. This review article focuses on the significance of adiponectin as a clinical biomarker of obesity-related diseases. Routine measurement of adiponectin in patients with lifestyle-related diseases is highly recommended.

Overweight associated with increased risk of erosive esophagitis in a non-obese Taiwanese population

Objective

To investigate the relationship between overweight and erosive esophagitis (EE) in a non-obese Taiwanese population.

Design and Methods

A total of 7,352 subjects (non-obese, 5,826; obese, 1,526) from a health examination center at National Cheng Kung University Hospital were enrolled. Central obesity was defined by a waist circumference (WC) ≥90 cm in male and 80 cm in female. Overweight was defined as body mass index (BMI) of 24–26.9 kg/m², and general obesity as BMI ≥27 kg/m². The Los Angeles classification was adopted to determine the presence of EE.

Results

There were significant differences in the prevalence of central obesity and different BMI status between subjects with and without EE in total and non-obese population. In total population, multivariate analyses revealed central obesity (OR, 1.17, 95% CI, 1.02–1.34, p = 0.021) and being obese (OR, 1.28, 95% CI, 1.07–1.52, p = 0.007)/overweight (OR, 1.25, 95% CI, 1.08–1.45, p = 0.003) had positive associations with EE in different model, respectively. When considering the joint effect of central obesity and BMI status, overweight (OR, 1.22; 95% CI, 1.04–1.44; p = 0.016) remained as an independent associated factor of EE but central obesity (OR, 1.06; 95% CI, 0.89–1.26; p = 0.549)/being obese (OR, 1.22; 95% CI, 0.98–1.53; p = 0.082) did not. As for non-obese group, separate model showed central obesity (OR, 1.19, 95% CI, 1.00–1.40, p = 0.046) and overweight (OR, 1.24; 95% CI, 1.07–1.44, p = 0.005) was positively associated with EE, respectively. However, being overweight (OR, 1.20; 95% CI, 1.02–1.42, p = 0.030) but not central obesity (OR, 1.08; 95% CI, 0.90–1.31; p = 0.398) was positively related to EE with considering the effect of overweight and central obesity simultaneously.

Conclusion

Overweight effect on EE was more detrimental than central obesity in non-obese subjects. In addition, male gender, hiatus hernia and alcohol use were also associated with increased risk of EE.

Central adiposity is associated with increased risk of esophageal inflammation, metaplasia, and adenocarcinoma: a systematic review and meta-analysis

BACKGROUND & AIMS

Central adiposity has been implicated as a risk factor for Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC), possibly promoting the progression from inflammation to metaplasia and neoplasia. We performed a systematic review and meta-analysis of studies to evaluate the association between central adiposity and erosive esophagitis (EE), BE, and EAC, specifically exploring body mass index (BMI)-independent and gastroesophageal reflux (GERD)-independent effects of central adiposity on the risk of these outcomes.

METHODS

We performed a systematic search of multiple databases through March 2013. Studies were included if they reported effect of central adiposity (visceral adipose tissue area, waist-hip ratio, and/or waist circumference) on the risk of EE, BE, and EAC. Summary adjusted odds ratio (aOR) estimates with 95% confidence intervals (CIs), comparing highest category of adiposity with the lowest category of adiposity, were calculated by using random-effects model.

RESULTS

Forty relevant articles were identified. Compared with patients with normal body habitus, patients with central adiposity had a higher risk of EE (19 studies; aOR, 1.87; 95% CI, 1.51-2.31) and BE (17 studies; aOR, 1.98; 95% CI, 1.52-2.57). The association between central adiposity and BE persisted after adjusting for BMI (5 studies; aOR, 1.88; 95% CI, 1.20-2.95). Reflux-independent association of central adiposity and BE was observed in studies that used GERD patients as controls or adjusted for GERD symptoms (11 studies; aOR, 2.04; 95% CI, 1.44-2.90). In 6 studies, central adiposity was associated with higher risk of EAC (aOR, 2.51; 95% CI, 1.54-4.06), compared with normal body habitus.

CONCLUSIONS

On the basis of a meta-analysis, central adiposity, independent of BMI, is associated with esophageal inflammation (EE), metaplasia (BE), and neoplasia (EAC). Its effects are mediated by reflux-dependent and reflux-independent mechanisms.

Association between obesity and Barrett's esophagus in a Japanese population: a hospital-based, cross-sectional study

Background

The association between obesity and Barrett’s esophagus (BE) in the Japanese population remains unclear. The prevalence of BE and its associated risk factors was examined.

Methods

A cross-sectional study of 1581 consecutive individuals who underwent upper gastrointestinal endoscopy was conducted. The prevalence of endoscopically suspected BE (ESBE) was evaluated. Obesity was evaluated by body mass index (BMI, ≥ 25 kg/m²) and waist circumference (WC) (males, ≥ 85 cm; females, ≥ 90 cm). Because endoscopic diagnosis of ultra-short ESBE (<1 cm in extent) is difficult and highly unreliable, this type of ESBE was excluded from the study.

Results

In proton pump inhibitor (PPI) non-users, the prevalence of ESBE ≥ 1 cm was 5.6%. In univariate analysis, male sex and reflux esophagitis (RE) were significantly associated with BE, but BMI, WC, and reflux symptoms were not. In multivariate logistic regression analysis, only RE (odds ratio [OR] = 3.48, 95% confidence interval [CI] 1.89-6.41, p < 0.0001) was an independent risk factor for BE; obesity and the other factors were not. In contrast, RE (OR 5.67, p = 0.0004) and large WC (OR 5.09, p = 0.0005) were significant risk factors for ESBE ≥ 1 cm in PPI users. Only male sex, but not obesity or the other risk factors, was associated with an increased risk of RE in patients not taking PPIs.

Conclusions

RE, but not obesity, may have an independent association with the risk of ESBE in the Japanese population. Furthermore, obesity measures were not independent risks for RE. Interestingly, PPI-refractory RE and large WC were risk factors for ESBE ≥1 cm in patients taking PPIs.

Upper gastrointestinal symptoms in obese patients and their outcomes after bariatric surgery

Obesity is considered an important risk factor for the development of gastrointestinal (GI) disorders, likely through alterations of GI motility. Even though gastroesophageal reflux disease is the condition mainly studied at present, the prevalence of other upper GI symptoms is also augmented in obese patients. Owing to their chronic trend, these disorders have a bearing on public spending and their correct diagnosis would avoid unnecessary cost-consuming investigations. Furthermore, bariatric surgery dramatically changes GI anatomy and physiology, influencing GI symptom outcomes. The aim of this review is to categorize the available results in a pathophysiological framework in an attempt to set up the correct clinical GI management of obese patients before and after bariatric surgery. This would be helpful in tentatively reducing their considerable economic burden on public health services.

Visceral fat predominance is associated with erosive esophagitis in Japanese men with metabolic syndrome

BACKGROUND AND AIM

Although visceral fat is strongly associated with metabolic syndrome (MS), the association between erosive esophagitis (EE) and visceral and subcutaneous fat types in individuals with MS has remained unclear. In this study, we divided individuals with MS into those with visceral and subcutaneous fat types, and determined the differences in the presence of EE between the types of MS in Japanese men.

METHODS

The participants were 265 men with MS who underwent a medical checkup including upper gastrointestinal endoscopy and abdominal ultrasonography. We made a distinction between visceral and subcutaneous fat types of MS by ultrasonography, and examined for the presence of EE, and the correlation between EE and other data.

RESULTS

Total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and the frequency of EE were significantly higher in visceral fat-type MS than in subcutaneous fat-type MS. On logistic regression analysis with EE as a dependent variable and the significant background factors as the independent variables, visceral fat-type MS and hiatal hernia were significant predictors of an increased prevalence of EE (odds ratios=3.808 and 8.599; 95% confidence intervals=1.710-8.479 and 4.206-17.58; P<0.005 and <0.001, respectively).

CONCLUSION

Japanese men with visceral fat-type MS are more likely to have dyslipidemia and EE than those with subcutaneous fat-type MS. Visceral fat-type MS is one of the most significant predictors of an increased prevalence of EE in Japanese men with MS.

High prevalence of gastroesophageal reflux symptoms in type 2 diabetics with hypoadiponectinemia and metabolic syndrome

Abstract

Trial Registration

UMIN 000002271.