Influence of dietary patterns on the risk of acute myocardial infarction in China population: the INTERHEART China study.

BACKGROUND: Some dietary patterns are risk factors for acute myocardial infarction (AMI). Chinese traditional food and habits vary from other cultures. The present study determined whether different dietary patterns were associated with AMI in Chinese people. METHODS: We conducted a case-control study. There were 1312 cases of first AMI and 2235 control subjects who did not have previous angina, diabetes mellitus, hypertension or stroke. Controls were matched to cases on age and gender. Diet was measured with a validated, 19 item food frequency questionnaire. We identified three major dietary patterns using factor analysis: vitamin and microelement pattern (high intake of vegetables, fruits and tofu), carbohydrate pattern (high in grain), and fat and protein pattern (high in meat, fish, eggs and fried foods). RESULTS: After adjusting for all risk factors, the vitamin and microelement pattern was inversely associated with AMI risk (global P value, 0.0001). Compared with the first quartile, the adjusted ORs of AMI were 0.81 (95%CI: 0.66 - 1.00) for the second quartile, 0.67 (95%CI: 0.54 - 0.82) for the third, and 0.70 (95%CI: 0.56 - 0.88) for the fourth. Several dietary frequencies (serves per week) including vegetables, fruits and tofu were closely associated with decrease of AMI risk. Carbohydrate pattern showed weak relationship with AMI. We observed a U-shaped association between frequencies of fat and protein pattern and AMI risk. Excessive fat intake increased the AMI risk. The adjusted OR of AMI associated with the higher level of green vegetables was 0.37 (95%CI: 0.24 - 0.57) in women and 0.65 (95%CI: 0.51 - 0.82) in men (P value for heterogeneity, 0.0140). CONCLUSIONS: Unhealthy dietary intake can increase the AMI risk. Improving intake of vegetables, fruits and tofu have the potential to partially prevent the rising epidemic of cardiovascular disease in China.