Dietary fats, carbohydrate, and progression of coronary atherosclerosis in postmenopausal women

Background: The influence of diet on atherosclerotic progression is not well established, particularly in postmenopausal women, in whom risk factors for progression may differ from those for men. Objective: The objective was to investigate associations between dietary macronutrients and progression of coronary atherosclerosis among postmenopausal women. Design: Quantitative coronary angiography was performed at baseline and after a mean follow-up of 3.1 y in 2243 coronary segments in 235 postmenopausal women with established coronary heart disease. Usual dietary intake was assessed at baseline. Results: The mean (+/-SD) total fat intake was 25+/-6% of energy. In multivariate analyses. a higher saturated fat intake was associated with a smaller decline in mean minimal coronary diameter (P = 0.001) and less progression of coronary stenosis (P = 0.002) during follow-up. Compared with a 0.22-mm decline in the lowest quartile of intake. there was a 0.10-mm decline in the second quartile (P = 0.002), a 0.07-mm decline in the third quartile (P = 0.002), and no decline in the fourth quartile (P < 0.001); P for trend = 0.001. This inverse association was more pronounced among women with lower monounsaturated fat (P for interaction = 0.04) and higher carbohydrate (P for interaction 0.004) intakes and possibly lower total fat intake (P for interaction 0.09). Carbohydrate intake was positively associated with atherosclerotic progression (P = 0.001), particularly when the glycemic index was high. Polyunsaturated fat intake was positively associated with progression when replacing other fats (P = 0.04) but not when replacing carbohydrate or protein. Monounsaturated and total fat intakes were not associated with progression. Conclusions: In postmenopausal women with relatively low total fat intake, a greater saturated fat intake is associated with less progression of coronary atherosclerosis. whereas carbohydrate intake is associated with a greater progression.