Association of whole and refined grains food consumption with coronary artery disease in a multi-center, case-control study of Iranian adults: Iran Premature Coronary Artery Disease (IPAD).

Background And Aims: Low whole grain food consumption is the leading cause of coronary artery disease (CAD) burden in middle-East countries. However, investigations examining the association of whole and refined grain foods and CAD are scarce in this region. We aimed to investigate the association of whole and refined grain foods with CAD in Iranians with different ethnicities.

Methods And Results: This was a multi-center case-control study among Iranian ethnicities consisting of Fars, Azari, Kurd, Arab, Lor, Gilak, Qashqaei, and Bakhtiari within the framework of the Iran premature coronary artery disease (IPAD) project. The data were collected from hospitals with catheterization laboratories. Cases were 2099 patients with a stenosis ≥75 % in at least one vessel or ≥50 % in the left main artery. Control group were 1168 individuals with normal angiography test. Grains intake was assessed using a validated semi-quantitative food frequency questionnaire. Compared with those with the lowest intake of whole grain foods, subjects in the top quartile had lower risk of CAD (OR = 0.54, 95 % CI: 0.40, 0.72; P < 0.001) after full adjustment. However, a significant direct link was found between higher refined grain foods consumption and the risk of CAD (OR = 1.43, 95 % CI: 0.91-1.84; P = 0.013).

Conclusion: Our findings support dietary recommendations to increase whole grain foods and mitigating refined grain food consumption to reduce the risk of CAD and its severity.