TOPLINE:

Higher vitamin B12 status in mid-to-late life was associated with slower declines in memory, executive function, and language compared to lower status in patients without baseline dementia, new research showed. Additionally, the associations for executive function and language — but not memory — persisted regardless of folate status.

METHODOLOGY:Researchers analyzed 1994 dementia-free adults (mean age, 60 years; 54% women; 99% non-Hispanic White individuals) from the Framingham Heart Study Offspring Cohort. All had at least two assessments of vitamin B12 biomarkers and neuropsychological test scores between 1998 and 2018.The participants were divided into four quartiles on the basis of the cumulative average of three vitamin B12 biomarkers: serum levels of cobalamin, methylmalonic acid, and total homocysteine, corrected for low folate levels.The primary outcomes were changes in memory, executive function, and language factor scores over a mean follow-up duration of 14.2 years.The analysis was adjusted for demographic, lifestyle, and medical factors, including age, education, and apolipoprotein E allele status.TAKEAWAY:Participants with a higher cumulative vitamin B12 status showed significantly slower annual cognitive decline than those with a lower B12 status in the domains of language (P for trend = .003), memory (P for trend = .004), and executive function (P for trend = .03).The highest B12 level was also associated with less cognitive decline (by 0.05-0.09 SD) over 10 years than the lowest level.The results were consistent across folate levels, though the association between B12 status and memory was slightly stronger in those with elevated folate levels (≥ 20 ng/mL).IN PRACTICE:

“Given that even small delays in the onset of symptoms can reduce the prevalence of cognitive impairment, efforts to manage vitamin B12 status and improve nutrition throughout the life course may help mitigate cognitive decline into older age,” the investigators wrote.

SOURCE:

The study was led by Francesca R. Marino, Boston University Chobanian and Avedisian School of Medicine, Boston. It was published online on October 21 in Alzheimer’s & Dementia.

LIMITATIONS:

The study population consisted primarily of European American participants, possibly reducing the generalizability of the findings. Neuropsychological test scores and vitamin B12 biomarkers were not measured at the same time, and different assays were used across study exams, which could introduce nondifferential error. Genetic data on polymorphisms affecting homocysteine or other B12 biomarkers were unavailable. Additionally, excluded participants were older with lower B12 or folate levels, which may have introduced selection bias.

DISCLOSURES:

The study was funded by the National Heart, Lung, and Blood Institute and the National Institute on Aging. Several investigators reported serving in advisory or editorial roles for several pharmaceutical and research organizations. Full details are provided in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.