Education, economic status and other risk factors in gastric cancer: "a case-control study of Turkish Oncology Group".

Diet and lifestyle related to socioeconomic status emerged as risk factors for gastric cancer in several studies. However, the results were not always consistent with the socioeconomic status. The aim of this study was to evaluate the risk factors independent from education as a measure of socioeconomic status. Two hundred and fifty-three patients with gastric cancer diagnosed in 2005 and equal number of control subjects were interviewed for several characteristics and diet. Matching was done for age, gender, city of residence and also for the level of education. Despite these matching preferences, patients had significantly lower income when compared to the control subjects (P = 0.0001). Higher rate of patients were smoking more than 2 packs/day of cigarettes (P = 0.018). Also significantly higher rate of control subjects were using antibiotics (P = 0.002). Coffee (P < 0.0001), salad (P = 0.006), bread (P = 0.005), vegetable-derived cooking oil (P = 0.003) consumptions appeared as highly protective factors against gastric cancer in univariate analysis in the present trial. In multivariate analysis, significant risk reducing factors were bread (P = 0.005) and coffee consumption (P = 0.0001) other than the level income (P = 0.002). In conclusion, the goal of obtaining comparable socioeconomic status by including the level of education in the matching criteria was not met in our study because of the difference in income level. The only risk reducing factor that was not in accordance with income level was the unexpectedly higher rate of bread consumption in control group.