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

JAMA. 2011 Aug 24;306(8):831-9. doi: 10.1001/jama.2011.1202.

Abstract

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.

Trial registration: clinicaltrials.gov Identifier: NCT00438425.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cholesterol, LDL / blood*
  • Counseling*
  • Diet*
  • Dietary Fats*
  • Dietary Fiber / administration & dosage
  • Female
  • Humans
  • Hyperlipidemias / diet therapy*
  • Male
  • Middle Aged
  • Nuts
  • Patient Compliance
  • Phytosterols / administration & dosage
  • Soybean Proteins / administration & dosage

Substances

  • Cholesterol, LDL
  • Dietary Fats
  • Dietary Fiber
  • Phytosterols
  • Soybean Proteins

Associated data

  • ClinicalTrials.gov/NCT00438425