Case-Control Study of Diet, Cooking Methods and Colorectal Cancer In Viet Nam

Abstract

Background: Colorectal cancer is one of the most common cancers and the leading cause of death in the world and the third most common cancer in Viet Nam. Aim: To examine the association between diet, cooking methods and the risk of colorectal cancer by a case-control study in the Hanoi city, Viet Nam. Methods: A case-control study was designed. Case was newly incident colorectal cancer (125 cases). Control was hospital-based case without any cancer and matched to case by sex and +/− 5 years old admitted to the same Bach Mai hospital in Hanoi city. Case to control ratio was one. Data collection was performed by face to face interviewed by the trained interviewers in using the validated semiquantitative food frequency and demographic and lifestyle questionnaires. Food frequency intake inquired about a frequent intake per day, per week, per month or per year for 85 items of fruit, vegetables, fishes, meats, salted foods, bean and nuts; lightly browned, medium browned, high browned, well browned, and blackened/charred of cooking meat and fishes. Multivariable adjusted odds ratio and 95% confidence interval (OR, 95% CI) was estimated using STATA 10.0. Results: The significant increased risk of colorectal cancer was observed for a high frequent intake of fried meat (OR=2.63, 95% CI: 1.47-4.66); fried soya cheese (OR=2.00, 95% CI: 1.05-3.80); grilled food (OR=3.18, 95% CI: 1.84-5.48); roasted food (OR=3.56, 95% CI: 2.05-6.20); beef (OR=2.06, 95% CI: 1.17-3.83); eat salty food (OR=1.71, 95% CI: 1.03-2.82); instant noodle (OR=3.08, 95% CI: 1.61-5.91); salted vegetable (OR=1.63, 95% CI: 1.01-2.73); smoking (OR=5.5, 95% CI: 1.90-15.96). In contrast, a significant decreased risk of colorectal cancer was seen for a high frequent intake of soymilk (OR=0.45, 95% CI: 0.24-0.87); sweet leaf (OR=0.28, 95% CI: 0.13-0.60); guava (OR=0.55, 95% CI: 0.32-0.94); orange (OR=0.15, 95% CI: 0.07-0.36). Conclusion: We observed the positive association between cooking methods and the risk of colorectal cancer. Further study of the underlying mechanisms of cooked meat and fish is highly recommended in Viet Nam.