Abstract P264: Healthy dietary interventions and Lipoprotein (a) plasma levels: Results from the Omni Heart Trial
Background: Increased lipoprotein (a) [Lp(a)] levels are associated with atherosclerotic cardiovascular disease. Plasma Lp(a) levels are mainly genetically determined by race with levels higher in blacks compared to whites. Dietary interventions have been reported to alter Lp(a) but evidence is sparse. No study has evaluated the effect of macronutrient composition on Lp(a) concentration and racial differences.
Objective: To compare three healthy, DASH-style dietary interventions differing in macronutrient content on the effect on Lp(a) concentrations in blacks and whites.
Design: Secondary analysis of a randomized, 3-period feeding study including 152 (88 blacks/64 whites) individuals. Participants were given DASH-type healthy diets rich in carbohydrates [Carb], in protein [Prot] or in unsaturated fat [Unsat Fat] for 6 weeks each. Plasma Lp(a) concentration was assessed at baseline and after each intervention.
Results: At baseline, median Lp(a) plasma level was 18 mg/dl overall, 9 mg/dl in whites and 28.5mg/dl in blacks. The Unsat Fat diet lowered Lp(a) by 1.2mg/dl (95% CI, -0.3,-2.2; p= 0.015) compared with the Carb diet, and by 2.7 mg/dl (95% CI, -1.7,-3.7; p<0.001) compared with the Prot diet (Table). The effects on Lp(a) of the controlled diets tended to be greater in blacks than whites, especially the reduction in Lp(a) on the Unsat compared to the Prot diet (-3.7 in blacks vs. -1.0 mg/dl in whites, P=0.008). On self-selected diet (prior to feeding) or intervention diets, blacks had higher mean Lp(a) than did whites.
Conclusions: Compared to diets rich in carbohydrate or protein, a DASH-type diet high in unsaturated fat lowered Lp(a). These changes were greater in blacks compared to whites. Our results highlight a potential means to reduce racial disparities in CVD.
Table: Differences in Lp(a) concentration (mg/dl) between study diets by ethnicity
Author Disclosures: B. Haring: None. M.C. Wyler von Ballmoos: None. L.J. Appel: None. F.M. Sacks: None.
- © 2014 by American Heart Association, Inc.