Dataset Information

Biochemical indicators of vitamin B12 and folate insufficiency and cognitive decline.

ABSTRACT:

Background

In some prospective studies, associations of serum vitamin B(12) and homocysteine concentrations with cognitive decline have been reported but few have examined the role of methylmalonic acid, a more specific marker of vitamin B(12) deficiency than homocysteine.

Objective

The aim of the study was to determine whether serum concentrations of vitamin B(12) or selected metabolites are related to cognitive decline.

Methods

A total of 516 subjects were selected in a stratified random sampling design from among Chicago Health and Aging Project participants for clinical evaluation. We used linear mixed models to examine the association of blood markers of vitamin B(12) status to change in cognitive scores over 6 years. Cognitive function was assessed every 3 years and measured as the sum of standardized scores on four tests.

Results

Probable vitamin B(12) deficiency was observed in 14.2% of the sample. Elevated serum concentrations of homocysteine were present in 19.2% of subjects, and of methylmalonic acid, in 36.4%. Higher serum methylmalonic acid concentrations were predictive of faster rates of cognitive decline (beta = -0.00016, SE = 0.0001, p = 0.004) and higher serum vitamin B(12) concentrations were associated with slower rates of cognitive decline (beta = +0.00013, SE < 0.0001, p = 0.005) in multivariable adjusted mixed models. Serum concentrations of homocysteine had no relationship to cognitive decline.

Conclusions

Serum methylmalonic acid and vitamin B(12) concentrations may be the more important risk factors for cognitive decline when compared to serum homocysteine concentrations, particularly in older populations exposed to food fortification and possible supplements containing folic acid.

SUBMITTER: Tangney CC

PROVIDER: S-EPMC2677500 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Biochemical indicators of vitamin B12 and folate insufficiency and cognitive decline.

Tangney Christine C CC Tang Yuxiao Y Evans Denis A DA Morris Martha Clare MC

Neurology 20090101 4

<h4>Background</h4>In some prospective studies, associations of serum vitamin B(12) and homocysteine concentrations with cognitive decline have been reported but few have examined the role of methylmalonic acid, a more specific marker of vitamin B(12) deficiency than homocysteine.<h4>Objective</h4>The aim of the study was to determine whether serum concentrations of vitamin B(12) or selected metabolites are related to cognitive decline.<h4>Methods</h4>A total of 516 subjects were selected in a s ...[more]

PMID: 19171834

Similar Datasets

Project description:More effective treatments are needed for negative symptoms of schizophrenia, which are typically chronic, disabling, and costly. Negative symptoms have previously been associated with reduced blood folate levels, especially among patients with low-functioning variants in genes that regulate folate metabolism, suggesting the potential utility of folate supplementation.To determine whether folic acid plus vitamin B12 supplementation reduces negative symptoms of schizophrenia and whether functional variants in folate-related genes influence treatment response.Parallel-group, randomized, double-blind, placebo-controlled clinical trial of 16 weeks of treatment with 2 mg of folic acid and 400 ?g of vitamin B12.Three community mental health centers affiliated with academic medical centers in the United States.Outpatients with chronic schizophrenia who were psychiatrically stable but displayed persistent symptoms despite antipsychotic treatment. Eligible patients were 18 to 68 years old, were treated with an antipsychotic agent for 6 months or more at a stable dose for 6 weeks or more, and scored 60 or more on the Positive and Negative Syndrome Scale.One hundred forty subjects were randomized to receive daily oral folic acid plus vitamin B12 or placebo.Change in negative symptoms (Scale for the Assessment of Negative Symptoms [SANS]), as well as positive and total symptoms (Positive and Negative Syndrome Scale).Folate plus vitamin B12 improved negative symptoms significantly compared with placebo (group difference, -0.33 change in SANS score per week; 95% CI, -0.62 to -0.05) when genotype was taken into account but not when genotype was excluded. An interaction of the 484C>T variant of FOLH1 (rs202676) with treatment was observed (P = .02), where only patients homozygous for the 484T allele demonstrated significantly greater benefit with active treatment (-0.59 change in SANS score per week; 95% CI, -0.99 to -0.18). In parallel, we observed an inverse relationship between red blood cell folate concentration at baseline and 484C allele load (P = .03), which persisted until 8 weeks of treatment. Change in positive and total symptoms did not differ between treatment groups.Folate plus vitamin B12 supplementation can improve negative symptoms of schizophrenia, but treatment response is influenced by genetic variation in folate absorption. These findings support a personalized medicine approach for the treatment of negative symptoms.clinicaltrials.gov Identifier: NCT00611806.

Dataset Information

Biochemical indicators of vitamin B12 and folate insufficiency and cognitive decline.

Background

Objective

Methods

Results

Conclusions

Publications

Biochemical indicators of vitamin B12 and folate insufficiency and cognitive decline.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets