Malignant High And Low Incidence Area In Jiangsu Province, The Influencing Factors Of Gastric Cancer In Epidemiological Studies

Although a consistently decreasing trend has been observed for stomachcancer in the recent decades, the mortality of stomach cancer remains thesecond most common cancer globally. Jiangsu is a province in China witha heavy cancer burden, with cancer-attributable mortality ranking firstamong all deaths since the 1970s. Most areas in the province have cancermortality above China's national average, however, geographicdifferences exist in cancer incidence and mortality across the province.Jiangsu has the highest mortality of stomach cancer in the Grand Canaltribunal area, such as Huai'an and Dafeng, and the lowest in the areabordering Shandong province, such as Tongshan and Ganyu. Mortalityand incidence of stomach cancer were significantly higher in Dafeng thanin Ganyu, so was the influence of stomach cancer on population health.Therefore, the present study selected Dafeng as the high stomach cancermortality area and Ganyu as the low mortality area. Case-control andcase-case approaches were used to compare the risk and protective factorsassociated with the risk of stomach cancer in two areas.Recommendations will be made based on the findings.In Dafeng, 649 cases and 1,847 controls were selected. Multi-factorialunconditional logistic regression analysis found that migration fromQidong and Haimen, eating fast, preference for salty foods, eatingspoiled foods, family history, and smoking are risk factors while eatingraw garlic, periodic cleaning of cereal storage containers, drinking greentea and cheerfulness are protective factors. Gender-specific analysisshows that smoking is a risk factor for men but not for women.Migration from Qidong and Haimen, eating fast are risk factors whileeating raw garlic, drinking green tea and cheerfulness are protectivefactors for both men and women. It was also found that green teadrinkers had a 55% decreased risk than non-green tea drinkers. Meanwhile a dose-response effect was found between the risk ofstomach cancer and tea concentration, duration of drinking and amountof drinking.In Ganyu, 342 cases and 1,593 controls were selected. Multi-factorialunconditional logistic regression analysis found family history, smoking,preference for salty, hot and spicy diet are risk factors, while green teaand cheerfulness are protective factors.Case-case comparative analysis between two areas found a higher familyhistory among Dafeng cases, a higher proportion of Dafeng cases drinkgreen tea and eat raw garlic than Dafeng controls. Drinking green tea andeating raw garlic are more common in the population in Ganyu than inDafeng, which may have a protective effect on stomach cancer for thewhole population.For the first time, the study found that Dafeng cases have a higherproportion of migrants from Qidong and Haimen than the generalpopulation. Further studies, using ecological, retrospective cohort, andmolecular epidemiological approaches, comparing Qidong and Haimenpopulations may help to understand why these migrants have higherstomach cancer mortality.The study examined preliminarily the risk and protective factors in highand low cancer mortality areas. Based on the preliminary findings,health education programs could be developed to promote these healthy(protective) lifestyle factors and change the alterable unhealthy (risky)lifestyles.