The association between body mass index and Barrett's esophagus: a systematic review

Epidemiology of Barrett's Esophagus and Esophageal Carcinoma

To care and treat patients with esophageal cancer, one must first understand the epidemiology of Barrett's esophagus (BE). BE is defined as the intestinal metaplasia occurring within the esophagus from normal squamous epithelium to abnormal specialized columnar epithelium. BE, while first described by Allison in 1948, was attributed to Norman Barrett in 1950, who reported a case of chronic peptic ulcer in the lower esophagus that was covered by columnar epithelium.

Preoperative Upper-GI Endoscopy Prior to Bariatric Surgery: Essential or Optional?

Introduction

The role of preoperative upper-gastrointestinal (GI) gastroscopy has been discussed with controversy in bariatric surgery. The aim of this study was to evaluate the incidence of upper-GI pathologies detected via endoscopy prior to bariatric surgery along with their clinical significance for patients’ management.

Material and Methods

In our single center prospectively established database of obese patients, who underwent bariatric surgery from January 2011 to December 2017, we retrospectively analyzed the perioperative endoscopic findings along with their influence on patients’ management.

Results

In total, 636 obese patients with median BMI (body mass index) of 49 kg/m² [range 31–92] received an upper-GI endoscopy prior to bariatric surgery. Among the surgical procedures, laparoscopic Roux-Y-gastric bypass (72.6%; n = 462) was the most frequent operation. Endoscopically detected pathological conditions were peptic ulcer 3.5% (22/636), Helicobacter pylori (Hp) gastritis 22.4% (143/636), and gastric or duodenal polyps 6.8% (43/636). Reflux esophagitis could be detected in 139/636 patients (21.9%). Barrett’s esophagus (BE) was histologically diagnosed in 95 cases (15.0%), whereas BE was suspected endoscopically in 75 cases (11.3%) only. Esophageal adenocarcinomas were detected in 3 cases (0.5%). Change of the operative strategy due to endoscopically or histologically detected pathologic findings had to be performed in 10 cases (1.6%).

Conclusion

Preoperative upper-GI endoscopy identifies a wide range of abnormal endoscopic findings in obese patients, which may have a significant impact on decision-making, particularly regarding the most suitable bariatric procedure and the appropriate follow-up. Therefore, preoperative upper-GI endoscopy should be considered in all obese patients prior to bariatric procedure.

Central Obesity and H. pylori Infection Influence Risk of Barrett's Esophagus in an Asian Population

Background and Aim

The prevalence rates of Barrett’s esophagus (BE) in western countries are higher than Asian ones, but little is known about their difference among risk factors of BE. The aim of this study is to investigate the associations of various risk factors including central obesity, body mass index (BMI), metabolic syndrome and H. pylori infection, with BE.

Methods

A total of 161 subjects with BE were enrolled and compared to age- and gender-matched controls randomly sampled (1:4) from check-up center in same hospital. Central obesity was defined by waist circumference (female>80cm; male>90cm), metabolic syndrome by the modified National Cholesterol Education Program Adult Treatment Panel III criteria in Taiwan. Independent risk factors for BE were identified by multiple logistic regression analyses.

Results

The mean age for BE was 53.8±13.7 years and 75.8% was male. H. pylori infection status was detected by the rapid urease test with the prevalence of 28.4% and 44.4% in the BE patients and controls, respectively. The univariate logistic regression analyses showed the risk was associated with higher waist circumference (odds ratio [OR], 2.53; 95% confidence interval [CI], 1.78–3.60), metabolic syndrome (OR, 2.02; 95% CI, 1.38–2.96) and negative H. pylori infection (OR, 0.50; 95% CI, 0.34–0.74). However, multivariate logistic regression analyses revealed that BE associated with higher waist circumference (adjusted OR, 2.79; 95% CI, 1.89–4.12) and negative H. pylori infection (adjusted OR, 0.46; 95% CI, 0.30–0.70).

Conclusions

Central obesity is associated with a higher risk of BE whereas H. pylori infection with a lower risk in an ethnic Chinese population.

Barrett esophagus in Asia: same disease with different pattern

Barrett esophagus (BE) is considered to develop as a result of chronic gastroesophageal reflux disease (GERD) and to predispose to esophageal adenocarcinoma (EAC). However, the disease pattern of BE in Asia differs from that observed in the West. For example, in the West, the prevalence rates of BE and EAC have progressively increased, whereas although the prevalence rate of GERD is increasing in Asia, the prevalence rates of BE and EAC have remained low in most Asian countries. GERD, hiatal hernia, old age, male sex, abdominal obesity (visceral obesity), smoking, alcohol consumption, and kyphosis are known risk factors for BE in Asia, and most Asian patients have short-segment BE. Helicobacter pylori infection is more prevalent in Asia than in the West. We suggest larger studies with a prospective design be conducted to elaborate further the different patterns of BE in Asia.

Barrett's esophagus in Latinos undergoing endoscopy for gastroesophageal reflux disease symptoms

Previous studies comparing the prevalence of Barrett's esophagus in Latinos and non-Latino whites are inconsistent. The aim of the study is to compare the prevalence of Barrett's esophagus in Latinos and non-Latino whites and to determine risk factors associated with Barrett's esophagus. Between March 2005 and January 2009, consecutive Latino and non-Latino white patients who underwent endoscopy for primary indication for symptoms of gastroesophageal reflux disease were identified by examining the internal endoscopy database at Los Angeles County + USC Medical Center. Barrett's esophagus was defined by columnar-lined distal esophagus on endoscopy confirmed by intestinal metaplasia on histology. Clinical features and endoscopic findings were retrospectively reviewed. The mean age of the 663 patients was 50 ± 12 years, 30% were male, and 92% were Latino. Compared with non-Latino whites, Latinos had more females (72% vs. 46%; P = 0.0001) and more Helicobacter pylori infection (53% vs. 24%; P = 0.003) but less tobacco use (7% vs. 17%; P = 0.01). Overall, 10% (68/663) of all patients had Barrett's esophagus whereas the prevalence was 10% (62/611) among the Latinos and 12% (6/52) among the non-Latino whites (OR 0.9, 95% CI 0.4-2.1; P = 0.75). One patient in the Latino group had high-grade dysplasia. On multivariate analysis, male gender (AOR 2.3, 95% CI 1.4-4.1; P = 0.002), diabetes (AOR 2.2, 95% CI 1.1-4.5; P = 0.03), and age ≥55 years (AOR 2.2, 95% CI 1.3-3.8; P = 0.006) were independently associated with Barrett's esophagus; Latino ethnicity remained nonsignificant (AOR 1.1, 95% CI 0.4-2.7; P = 0.88). In Latinos undergoing endoscopy for gastroesophageal reflux disease symptoms, the prevalence of Barrett's esophagus was 10%, comparable with non-Latino white controls as well as the prevalence previously reported among Caucasians. In addition to established risk factors, diabetes was associated with Barrett's esophagus.

Current status of Barrett's esophagus research in Asia

In Western countries, the epidemiology of esophageal cancer has changed considerably over the past decades with a rise in the ratio of adenocarcinoma to squamous cell carcinoma. Although the prevalence of gastroesophageal reflux is increasing in Asia, the prevalences of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) have remained low in most Asian countries. The Asian Barrett's Consortium recently conducted a review of published studies on BE from Asia to assess the current status of BE research in Asia, and to recommend potential areas for future BE research in the region. Differences in study design, enrolled population, and endoscopic biopsy protocols used have led to substantial variability in the reported BE prevalence (0.06% to 19.9%) across Asia. In particular, some Japanese studies used diagnostic criteria that differed considerably from what was used in most Asian studies. As in Western countries, increased age, male sex, tobacco smoking, reflux symptoms, and erosive esophagitis have been found to be risk factors for BE in several case-control studies from Asia. The Prague C and M criteria, developed to provide better interobserver reliability in diagnosis and grading of BE, are currently under extensive evaluation in the Asian population. There is a need for standardized protocols for endoscopic and histopathologic diagnosis before initiating collaborative projects to identify etiologic determinants of BE and its ensuing malignant transformation. At present, data regarding the management and long-term outcome of BE are extremely limited in Asia. More studies of BE in this geographic area are warranted.

Global epidemiology of Barrett's esophagus

Barrett's esophagus (BE) is defined as a metaplastic change of the distal esophageal epithelium from squamous to columnar type epithelium with the presence of intestinal metaplasia. There is a striking geographic variation in the prevalence rates of BE. Most epidemiological data on BE are derived from patients undergoing endoscopy and do not reflect prevalence rates in the general population. BE is much more common in the West when compared with Asia and Africa. Although BE is less common in Asia, the demographics are similar to the West, being predominantly found in older men with longer duration of reflux symptoms. Some studies from the West have suggested an increase in prevalence rates of BE. An increase in prevalence rates will have significant implications for health resource utilization and costs, due to the small but significant risk of developing esophageal adenocarcinoma. Endoscopic surveillance with the aim of detecting early lesions has been advocated. Compared with conventional white-light endoscopy with blind four-quadrant biopsies, the use of image-enhanced endoscopy, including chromoendoscopy, may improve detection of subtle mucosal irregularities and facilitate targeted biopsies. However, a truly cost-effective surveillance strategy remains to be determined.

Barrett esophagus: an update

Many developments have been made in the field of Barrett esophagus that have tremendous clinical implications. There are new definitions of Barrett esophagus that have had an immediate clinical impact on cancer risk and screening. Of interest is the definition by the British Society of Gastroenterology, which does not require the presence of intestinal metaplasia for a diagnosis of Barrett esophagus. Imaging techniques that allow improved visualization of intestinal metaplasia at the cellular level are now being used in clinical practice. New hypotheses elucidating the progression from squamous epithelium to intestinal metaplasia have been proposed. Indeed, the crucial role that transcription factors have in the pathogenesis of Barrett esophagus has been clarified. Improved characterization of the molecular mechanisms underlying Barrett esophagus is an incentive to undertake more basic science research in this field. Such research could also help with the development of chemoprevention strategies for this precancerous condition. This Review discusses the advances in understanding of the pathogenesis, diagnosis and treatment of Barrett esophagus.