A vitamin/nutriceutical formulation improves memory and cognitive performance in community-dwelling adults without dementia

Abstract

Adults of both genders without dementia consumed a nutriceutical formulation ("NF," consisting of folic acid, B12, Vitamin E, S-adenosylmethionine, N-acetyl cysteine and Acetyl-L-carnitine), previously shown to improve cognitive performance in Alzheimer's disease, or placebo. Participants receiving NF but not placebo improved statistically and clinically in the California Verbal Learning Test II and the Trail-Making Test. Both groups improved further during a 3-month open-label extension. Additional individuals displayed identical improvement during a separate 6-month open-label trial. Performance declined to baseline following withdrawal of NF, and statistically improved when participants resumed taking NF. Additional participants receiving NF but not placebo demonstrated improvement within 2 weeks in Trail-making and Digit-Memory tests; both groups improved in a 2-week open-label extension. An increased percentage of participants > or = 74 years of age did not show improvement with NF, which may relate to age-related difficulties in adsorption and/or basal nutritional deficiencies, or age-related cognitive decline during the course of this study. These findings support the benefit of nutritional supplements for cognitive performance and suggest that additional supplementation may be required for the elderly.

Figure 1

NF improves performance on the CVLTII Participants completed the CVLT II at baseline and after 3 months of taking NF or placebo under blind conditions. Panel A presents results from the immediate word repetition (T score), short-recall and long-recall test components as indicated. Note that NF and placebo groups displayed an equivalent T score, and neither group displayed improvement in long recall; however, participants receiving NF statistically improved (p<0.001) in short recall (asterisk). Panel B presents a composite score generated by giving equal weight to all 3 of the above test components; participants receiving NF displayed clinical improvement (0.35).

Figure 2

NF improves performance on the Trail-making test: a delayed-start trial with an open label extension Participants completed the Trail-making tests (parts A and B) at baseline and after 3 months of taking NF or placebo (“delayed start”) under blind conditions; values represent the mean (± standard error of the mean) normalized scores for Trails B - Trails A. A subset of participants also completed testing at 1.5 months; participant numbers and p values versus baseline (2-tailed Student’s t test) for each time point are indicated along the base of the graph. Note that participants receiving NF differed statistically by 3 months. After 3 months, code was broken and all participants received NF in an open-label extension until 6 months; note that all participants improved during this extension. NF was withdrawn between 6 and 9 months; note the decline in mean performance of all participants. NF was re-administered from 9 to 12 months; note statistical improvement for both the original NF and delayed-start groups.

Figure 3

NF improves cognitive performance on the Trail-making test: an open-label trial Participants completed the Trail-making tests (parts A and B) at baseline and after 3 and 6 months of taking NF under open-label conditions. Data from Fig. 2 for participants taking NF or placebo for 3 months under blind conditions, and their corresponding open-label extension, are reproduced to facilitate comparison. Note identical improvement in performance for participants receiving NF under blind or open-label conditions.

Figure 4

NF improves cognitive performance within 2 weeks Participants completed the Trail-making and the Digit-Memory tests at baseline, after receiving NF or placebo under blind conditions (“delayed start”) for 2 weeks, and after a 2-week open-label extension (in which all participants received NF). Note improvement for participants receiving NF but not placebo in both tests under blind conditions, and improvement for both groups during the open-label extension.

Figure 5

NF efficacy is reduced by age Participants receiving NF under blind conditions were grouped according to ages as indicated, then separated into “responders” if they demonstrated improvement in the Trail-making test after 3 months and “non-responders” if they did not demonstrate any improvement as described in Methods. Panel A presents mean Trails B-A scores (± standard error) for these groups. Note that scores differed significantly (p<0.05) between responders and non-responders for all age groups, and responders within all age groups, including those >74 years of age, displayed similar levels of improvement. Note further that non-responders within all age groups up 74 years of age also displayed similar scores, while those >74 years of age displayed substantially poorer scores at 3 months than did all other age groups. Panel B presents the percentage of participants that were responders within these age groups. Note the decline in responders with age.