French adults' cognitive performance after daily supplementation with antioxidant vitamins and minerals at nutritional doses: a post hoc analysis of the Supplementation in Vitamins and Mineral Antioxidants (SU.VI.MAX) trial

Am J Clin Nutr. 2011 Sep;94(3):892-9. doi: 10.3945/ajcn.110.007815. Epub 2011 Jul 20.

Abstract

Background: Antioxidant properties of some vitamins and trace elements may help to prevent cognitive decline.

Objective: The aim of the current study was to estimate the long-term effects of antioxidant nutrient supplementation on the cognitive performance of participants in the Supplementation in Vitamins and Mineral Antioxidants (SU.VI.MAX) study 6 y after the end of the trial.

Design: This study included 4447 French participants aged 45-60 y who were enrolled in the SU.VI.MAX study (1994-2002), which was a double-blind, placebo-controlled, randomized trial. From 1994 to 2002, participants received daily vitamin C (120 mg), β-carotene (6 mg), vitamin E (30 mg), selenium (100 μg), and zinc (20 mg) in combination or as a placebo. In 2007-2009, the cognitive performance of participants was assessed with 4 neuropsychological tests (6 tasks). Principal components analysis (PCA) was performed to identify cognitive-function summary scores. Associations between antioxidant supplementation and cognitive functions, in the full sample and by subgroups, were estimated through ANOVA and expressed as mean differences and 95% CIs. Subgroup analyses were performed according to baseline characteristics.

Results: Subjects receiving active antioxidant supplementation had better episodic memory scores (mean difference: 0.61; 95% CI: 0.02, 1.20). PCA indicated 2 factors that were interpreted as showing verbal memory and executive functioning. Verbal memory was improved by antioxidant supplementation only in subjects who were nonsmokers or who had low serum vitamin C concentrations at baseline.

Conclusion: This study supports the role of an adequate antioxidant nutrient status in the preservation of verbal memory under certain conditions. This trial was registered at clinicaltrials.gov as NCT00272428.

Publication types

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

MeSH terms

  • Antioxidants / pharmacology
  • Antioxidants / therapeutic use*
  • Ascorbic Acid Deficiency
  • Cognition / drug effects*
  • Dietary Supplements*
  • Double-Blind Method
  • France
  • Humans
  • Memory / drug effects*
  • Memory Disorders / prevention & control*
  • Micronutrients / pharmacology
  • Micronutrients / therapeutic use*
  • Middle Aged
  • Minerals / pharmacology
  • Minerals / therapeutic use*
  • Principal Component Analysis
  • Smoking
  • Time Factors
  • Trace Elements / pharmacology
  • Trace Elements / therapeutic use
  • Vitamins / pharmacology
  • Vitamins / therapeutic use

Substances

  • Antioxidants
  • Micronutrients
  • Minerals
  • Trace Elements
  • Vitamins

Associated data

  • ClinicalTrials.gov/NCT00272428