Efficacy of Vitamin B Supplementation on Cognition in Elderly Patients With Cognitive-Related Diseases

Abstract

Increase in serum homocysteine is shown to be a potential risk factor for cognitive impairment. Evidence suggests that vitamin B supplementation may reduce cognitive decline by lowering the homocysteine levels. The current meta-analysis evaluated the efficacy of folic acid along with vitamin B12 and/or B6 in lowering homocysteine, thereby attenuating cognitive decline in elderly patients with Alzheimer disease or dementia. Randomized controlled trials (RCTs) comparing the efficacy of folate and B vitamin supplementation in patients with cognitive decline secondary to Alzheimer disease or dementia were identified using the keywords, "homocysteine, hyper-homocysteinemia, B vitamin, vitamin B6, B12, folic acid, cognitive, Alzheimer's disease, and dementia." The outcome measures analyzed were the Mini-Mental State Examination (MMSE) score and serum homocysteine. Of the 77 studies identified, 4 RCTs were included in the current meta-analysis. The baseline characteristics, age, and gender distribution of patients among the 2 groups (supplement vs placebo) were comparable. The results reveal that the intervention group achieved significantly greater reduction in homocysteine levels than the control (pooled difference in means = -3.625, 95% confidence interval [CI] = -5.642 to -1.608, P < .001). However, no significant difference in MMSE (pooled difference in means = 0.027, 95% CI = -0.518 to 0.573, P = 0.921) was observed between the groups. Taken together, vitamin B supplementation was effective in reducing serum homocysteine levels. However, it did not translate into cognitive improvement, indicating that the existing data on vitamin B-induced improvement in cognition by lowering homocysteine levels are conflicting.

Vitamin B12 and Semen Quality

“…In the last decade, various research studies worldwide have reported low levels or deficiency in vitamin B 12 among the studied populations [13,14,15]. As a consequence, B 12 supplementation has been recommended in many occasions as a key contribution to the maintenance and enhancement of population health [13,15,16].…”

“…As a consequence, B 12 supplementation has been recommended in many occasions as a key contribution to the maintenance and enhancement of population health [13,15,16]. Vitamin B 12 deficiency was found to be multifactorial, and most of time it was related to malabsorption, malnutrition, or drug induced causes [17,18].…”

MTHFR Ala222Val polymorphism and clinical characteristics confer susceptibility to suicide attempt in chronic patients with schizophrenia

“…Second, there was a significant difference in the age between suicide attempters and non-attempters. Many studies have found that the common factors which may exacerbate folate deficiency are (2020) 10:5008 | https://doi.org/10.1038/s41598-020-57411-1 www.nature.com/scientificreports www.nature.com/scientificreports/ older age, male sex, and alcoholism [61][62][63] . Third, there were more female subjects in the SCZ group, which may have led to bias in the statistical analysis due to the imbalance in the number of subjects in each sex category in our current study.…”

Diet Associated with Inflammation and Alzheimer’s Disease

“…The B vitamins appeared to lower the subjects' homocysteine levels, resulting in reduced gray matter atrophy and slower cognitive decline [24]. However, a metaanalysis by Zhang and colleagues found that while intervention groups treated with vitamins B6, B12, and folate often experienced a reduction in homocysteine levels, these reductions were not translated into better cognition [25]. As demonstrated by these two studies, the effects of the B vitamins on cognition are uncertain.…”