Effect of a Dietary Portfolio of Cholesterol-Lowering Foods Given at 2 Levels of Intensity of Dietary Advice on Serum Lipids in Hyperlipidemia A Randomized Controlled Trial

Context Combining foods with recognized cholesterol-lowering properties (dietary portfolio) has proven highly effective in lowering serum cholesterol under metabolically controlled conditions. Objective To assess the effect of a dietary portfolio administered at 2 levels of intensity on percentage change in low-density lipoprotein cholesterol (LDL-C) among participants following self-selected diets. Design, Setting, and Participants A parallel-design study of 351 participants with hyperlipidemia from 4 participating academic centers across Canada (Quebec City, Toronto, Winnipeg, and Vancouver) randomized between June 25, 2007, and February 19, 2009, to 1 of 3 treatments lasting 6 months. Intervention Participants received dietary advice for 6 months on either a low-saturated fat therapeutic diet (control) or a dietary portfolio, for which counseling was delivered at different frequencies, that emphasized dietary incorporation of plant sterols, soy protein, viscous fibers, and nuts. Routine dietary portfolio involved 2 clinic visits over 6 months and intensive dietary portfolio involved 7 clinic visits over 6 months. Main Outcome Measures Percentage change in serum LDL-C. Results In the modified intention-to-treat analysis of 345 participants, the overall attrition rate was not significantly different between treatments (18% for intensive dietary portfolio, 23% for routine dietary portfolio, and 26% for control; Fisher exact test, P=.33). The LDL-C reductions from an overall mean of 171 mg/dL (95% confidence interval [CI], 168-174 mg/dL) were -13.8% (95% CI, -17.2% to -10.3%; P<.001) or -26 mg/dL (95% CI, -31 to -21 mg/dL; P<.001) for the intensive dietary portfolio; -13.1% (95% CI, -16.7% to -9.5%; P<.001) or -24 mg/dL (95% CI, -30 to -19 mg/dL; P<.001) for the routine dietary portfolio; and -3.0% (95% CI, -6.1% to 0.1%; P=.06) or -8 mg/dL (95% CI, -13 to -3 mg/dL; P=.002) for the control diet. Percentage LDL-C reductions for each dietary portfolio were significantly more than the control diet (P<.001, respectively). The 2 dietary portfolio interventions did not differ significantly (P=.66). Among participants randomized to one of the dietary portfolio interventions, percentage reduction in LDL-C on the dietary portfolio was associated with dietary adherence (r=-0.34, n=157, P<.001). Conclusion Use of a dietary portfolio compared with the low-saturated fat dietary advice resulted in greater LDL-C lowering during 6 months of follow-up.