Risk Factors Of Intestinal Metaplasia In Northwest Of China

?Background and Aims?The incidence and mortality of gastric cancer is the fourth and the second of the world, respectively. Correa model suggests that gastric cancer usually develops from chronic superficial gastritis, chronic atrophic gastritis, intestinal metaplasia(IM), atypical hyperplasia and eventually to cancer. Gastric IM and atypical hyperplasia are precancerous lesions of gastric cancer. A large number of clinical investigations showed that the 5-year survival rate of the patients with advanced gastric cancerisis less than 20%, whereas for the early gastric cancer, the 5-year survival rate is as high as 90%. The key steps of prevention and treatment of gastric cancer are lowering the incidence and improving the early diagnosis. It is important to mornitor the precancerous lesions of gastric cancer.Clinical studies suggest that the proper follow-up of high-risk patients can significantly improve the early diagnosis of gastric cancer. In general, there should be about 10 to 20 years for gastric IM to evolve into gastric cancer. However, the time for atypical hyperplasia is about 3 to 5 years. Therefore, gastric IM should be foucused on for the prevention and control of gastric cancer. To this point, it is very important to clarify the risk factors associated with gastric IM. The present study aimed to find out the risk factors of gastric IM in northwest of China by case-control study.?Methods?The study was proposed by case-control study with a well-designed questionnaire,including basic information and related factors. Related factors are age, gender, height,body mass index, smoking, drinking, Helicobacter pylori(H. pylori) infection, family history of gastric cancer, bile reflux, diarrhea, constipation, tea intake, coffee, high salt diet, spicy food, dairy intake,vitamin C, fresh fruit and vegetable intake, the usage of non-steroid anti-inflammation drugs, education and income level. From August 2014 to August 2015, 2157 cases that came from Xijing hospital and the second affiliated hospital of Xi 'an Jiaotong University undergoing gastroscopy were enrolled in the study. The subjects with gastric IM reported by gastroscopy and/or pathology were classified as IM group(experimental group), the subjects without IM were the control group. H. pylori infection was measured by 13C- or 14C-urea breath test or by rapid urease test. The statistic methods used in the study were t test, chi-square test, Fisher's exact test and Logistic regression.?Results?Totally, 332 IM subjects were reported by gastroscopy in our study. Among them,256 subjects(77.1%) were mild cases, 58 subjects(17.5%) were moderate cases and the last 18 subjects(5.4%) were severe cases. Univariate analysis showed that the ralated factors of IM were age ? 60 yr, male gender, H. pylori infection, smoking, alcohol consumption, high salt diet, spicy food, tea intake, family history of gastric cancer and the fresh vegetables intake. The height, body mass index, bile reflux, diarrhea, constipation,coffee, dairy intake, vitamin C, non-steroid anti-inflammatory drugs, education and income level had no significant relationship with gastric IM. The multivariate analysis indicated that the independent risk factors of IM were age?60yr(OR, 2.27; 95%CI, 1.70 to 3.03; P ? 0.001), H. pylori infection(OR, 2.67; 95%CI, 2.22 to 3.21; P ? 0.001),smoking(OR, 2.20; 95%CI, 1.54 to 3.15; P?0.001), family histry of gastric cancer(OR,2.22; 95%CI, 1.48 to 3.33; P ? 0.001), high salt diet(OR, 1.58; 95%CI, 1.18 to 2.13;P=0.002), spicy food(OR, 1.46; 95%CI, 1.08 to 1.96; P=0.013).?Conclusion?The risk factors of IM in northwest of China were age?60yr, H. pylori infection,smoking, family history of gastric cancer, high salt diet andspicy food. It is important to monitor and screen theelderpatients, especially the ones with a family history of gastric cancer. For the patients with a high risk of gastric cancer, eradicating H. pylori therapy is recommonded(if the H. pylori is positive). They also should be recmmonded to quit smoking and to avoid high salt diet and spicy food.