EPIDEMIOLOGY OF BARRETTS ESOPHAGUS

描述：巴雷特食道是一种发展中的化生疾病。 在估计有10%-20%的长期胃食道反流者中 疾病(GERD)。患有这种疾病的患者风险很高，估计为 每年1-2%的发展中的食管腺癌，一个迅速致命的 一种癌症，由于未知的原因，自 20世纪70年代中期。尽管很多研究都是为了找出 Barrett‘s食管病患者病情进展的预测因子 关于这种情况本身的原因的信息很少。第一 本病例对照研究的具体目的是比较新发病例和新发病例。 诊断为Barrett‘s食道(N=335) 人口(N=335)来检验特定环境的假设 暴露和宿主因素增加了巴雷特化生的风险，并 估计可归因于它们的病例的比例。也要接受检查 会起到肥胖的作用，饮食中高脂肪低水果 蔬菜，低血清维生素C、维生素E、类胡萝卜素和硒， 吸烟、饮酒、服用促进反流的药物以及 家族病史。第二个具体目标是确定决定因素 严重和持续性GERD患者的Barrett‘s食道 将病例与接受上内窥镜检查的患者进行反流症状比较， 但活检证实Barrett‘s食道阴性的患者(N=335)。 具体地说，需要检验的假设是，在GERD患者中： 1)吸烟、饮酒和亚硝胺饮食摄入量 与巴雷特食道的风险增加有关，而且更高 饮食摄入量和血清抗氧化剂水平与 降低风险；以及2)十二指肠胃反流(以浓度衡量 空腹胃液中胆汁的含量)与罹患 化生。短节段巴雷特综合征的流行程度将被估计 在接受胃镜检查治疗GERD的患者中，使用最大样本 到目前为止，接受内窥镜检查的患者都按照标准方案进行了活组织检查。 鉴于95%的巴雷特食管症患者仍未得到诊断， 食管腺癌的存活率是惨淡的，最直接的 预防降低食管腺癌发病率的措施 化生，而不是通过监测和治疗患者 已经被诊断出患有这种疾病。

DESCRIPTION: Barrett's esophagus is a metaplastic condition that develops in an estimated 10-20% of persons with long-standing gastroesophageal reflux disease (GERD). Patients with this condition are at high risk, estimated at 1-2% per year, of developing esophageal adenocarcinoma, a rapidly fatal cancer that, for unknown reasons, has risen sharply in incidence since the mid-1970s. Although much research has been directed toward identifying predictors of progression i patients with Barrett's esophagus, there is little information about the causes of the conditions itself. The first Specific Aim of this case-control study is to compare cases with newly diagnosed Barrett's esophagus (N=335) to controls from the general population (N=335) to test the hypothesis that specific environmental exposures and host factors increase risk of Barrett's metaplasia, and to estimate the fraction of cases attributable to them. Also to be examined will be the role of obesity, diet high in fat and low in fruits and vegetables, low serum vitamin C, vitamin E, carotenoids and selenium, tobacco use, alcohol consumption, use of medications that promote reflux and family history. The second Specific Aim is to identify determinant of Barrett's esophagus among individuals with severe and persistent GERD, by comparing cases to patients undergoing upper endoscopy for reflux symptoms, but who are biopsy-proven negative for Barrett's esophagus (N=335). Specifically, the hypothesis to be tested is that among patients with GERD: 1) cigarette smoking, alcohol consumption and dietary intake of nitrosamines are associated with increased risk of Barrett's esophagus, and that higher dietary intake and serum levels of antioxidants are associated with decreased risk; and 2) duodenogastric reflux (measured as the concentration of bile in fasting gastric juice) is associated with an increased risk of metaplasia. The prevalence of short-segment Barrett's will be estimated among patients undergoing endoscopy for GERD, using the largest sample of endoscoped patients, to date, all biopsied according to a standard protocol. Given that 95% of persons with Barrett's esophagus remain undiagnosed and that esophageal adenocarcinoma survival rates are dismal, the most direct means of reducing esophageal adenocarcinoma incidence amy be by preventing metaplasia, rather than by the surveillance and treatment of patients already diagnosed with the condition.