Could a multivitamin give three years of age-related memory change back to patients?

A study published last week led by researchers at Columbia University and Brigham and Women’s Hospital, Harvard Medical School explored the effects of multivitamin supplementation on memory in older adults. Additionally, the study explored whether multivitamin supplementation differentially affected individuals with a history of cardiovascular disease (CVD).^[]

“The maintenance of cognitive abilities is a top priority for older adults,” the authors write. “Healthy dietary patterns are implicated in slowing cognitive aging and may explain some degree of inter-individual differences in cognitive change over time.”

The COcoa Supplement and Multivitamin Outcomes Study Web (COSMOS-Web) randomly provided 3,562 older adults with either Centrum Silver, a multivitamin supplement, or a placebo. The participants were initially evaluated at the start of the study and then again annually through a series of neuropsychological tests for three years. Researchers looked for changes in episodic memory over three years of follow-up, along with changes in performance on the neuropsychological tests.

The COSMOS-Web tests, which participants could take from their home computers, primarily focused on the ModRey test, an episodic memory test.^[] In this study, the participants were given a 20-item word recall task and tested for immediate recall. The ModRey, the authors note, “is the outcome measure designed to be most sensitive and specific to hippocampus function…and we therefore pre-specified it as our primary outcome measure.”

An additional outcome included the ModBent, an object recognition memory task.^[] The authors noted that the ModBent was initially designed as the primary test for the study, but prior to the end of the trial, researchers changed it to a secondary outcome, citing concerns about its psychometric properties. In the Modbent task, the “outcome measure was the reaction time to the correctly rejected lures during the recognition trials. This task is related to the functioning of the dentate gyrus of the hippocampus,” the authors write.

Additionally, the researchers included the Color/Directional Flanker test, which measures the effect of conflicting information within a stimulus set. As the authors noted, this test “measure[s]...executive control…Performance on this task is mediated by the prefrontal cortex.”

Results

Researchers found that, compared to participants in the placebo group, those in the multivitamin supplementation group had significantly better ModRey immediate recall between baseline and year one—the primary outcome of the study.

The researchers noted that “[t]he contrast estimate of the multivitamin versus placebo effect averaged across all three years of follow-up demonstrated a significant effect of multivitamin intervention, suggesting that the improvement in memory is sustained, on average, over at least the three years post-baseline.”

“Although our observed effect size is small and may not be noticeable to all individuals receiving multivitamin supplementation, even small effect sizes can result in large health benefits at the population level,” the authors state. “Based on cross-sectional analysis of the association between age and performance on the ModRey, we estimate that the effect of the multivitamin intervention improved memory performance above placebo by the equivalent of 3.1 years of age-related memory change.”

The multivitamins did not affect all of the outcomes, however. The researchers state that multivitamin supplementation did not significantly affect memory retention, executive function, or novel object recognition.

Regarding CVD and multivitamin supplementation, the researchers found that participants with a history of CVD had lower baseline ModRey scores than those without a history of CVD. And in a randomized cohort sample of participants, “the effect of multivitamin supplementation on improvement in ModRey immediate recall memory at the one-year follow-up was significantly higher than placebo in participants reporting a history of CVD compared to participants with no history of CVD.”

But why were the effects more pronounced in participants with a history of CVD? The study’s leader, Adam M. Brickman, PhD, Professor of Neuropsychology at Columbia University Vagelos College of Physicians and Surgeons, told MDLinx, “We can only speculate at this time. Older adults with cardiovascular risk factors tend to have lower vitamin and mineral circulating levels. Supplementation with multivitamins may help restore these deficiencies, providing [a] secondary benefit to cognitive health.”

What do these findings mean? 

These findings mean that physicians should consider whether multivitamin supplementation is appropriate for their patients. “Although the evidence of a general health benefit for multivitamin supplementation is mixed, our study joins a more consistent growing body of research that indicates its potential benefit for cognitive health in older adults,” Brickman says.

Further research is also necessary. The researchers state that although the study reveals specific outcomes, it does not provide information about the mechanisms underlying the effects. Other limitations included the fact that participants were primarily well-educated and White.

Brickman notes the need for more diversity: “We need to test whether multivitamin supplementation has beneficial cognitive effects in more diverse, older adults than those included in our study to understand whether the findings generalize to individuals more representative of the US population.”

Moving forward, the researchers note that “[f]uture studies should examine specific nutrients or nutrient combinations that contribute to cognitive health in aging.” In the study, the researchers tested the blood of a small group of participants to confirm increases in folate, vitamin B12, and serum 25(OH)vitamin D, as “[l]ow vitamin levels, including vitamin B and vitamin D, may be linked to cognitive decline…as well as dementia.”