Background: Higher intake of fiber, especially cereal fiber, has been associated with reduced risk of cardiovascular events and mortality. However, there are limited data on the effect of fiber intake on measures of progression of coronary artery disease (CAD). The aim was to examine the association between intakes of total fiber and fiber from different dietary sources and progression of coronary-artery atherosclerosis among women with established CAD.
Methods: A prospective cohort study involved postmenopausal women (n = 229) participating in the Estrogen Replacement and Atherosclerosis trial. Usual fiber intake was estimated at baseline using a food frequency questionnaire. Quantitative coronary angiography was performed at baseline and after 3.2 +/- 0.6 (mean +/- SD) years to assess changes in mean minimum coronary artery diameter and mean percent stenosis.
Results: Compared to lower intakes, > 3 g/4184 kJ (1000 kcal) of cereal fiber or > 6 servings of whole grains per week were associated with smaller decline in minimum coronary artery diameter (cereal fiber: -0.09 +/- 0.02 vs -0.04 +/- 0.02 mm, P = .03; whole grains: -0.10 +/- 0.02 vs -0.06 +/- 0.02 mm, P = .04) after adjustments for age, cardiovascular risk factors, and dietary intakes of saturated and polyunsaturated fat, cholesterol, and alcohol. Progression in percent stenosis tended to be less in women with higher intake of cereal fiber (P = .10) or whole-grain foods (P = .09), after similar adjustments. Intakes of total, fruit, and vegetable fiber, and number of servings of refined grain, fruits, or vegetable were not associated with progression.
Conclusions: Higher intakes of cereal fiber and whole-grain products are associated with less progression of coronary atherosclerosis in postmenopausal women with established CAD.