Methylmalonic acid and cognitive function in the Medical Research Council Cognitive Function and Ageing Study.

Abstract

BACKGROUND:

An elevated blood concentration of homocysteine is an established risk factor for cognitive impairment and dementia, but associations between cognition and methylmalonic acid (MMA), a related metabolic marker of vitamin B-12 deficiency, are less clear.

OBJECTIVE:

The aim was to determine the utility of serum MMA and holotranscobalamin as markers of vitamin B-12 status in relation to cognitive function and to investigate their association with discrete cognitive domains.

DESIGN:

This was a cross-sectional survey of 84 nondemented elderly participants (aged >69 y) from the Welsh cohort of the Medical Research Council's Cognitive Function and Ageing Study. Cognitive status was determined by Mini-Mental State Examination (MMSE) and the Cognitive Section of the Cambridge Mental Disorders of the Elderly Examination (CAMCOG).

RESULTS:

Nearly one-half (43%) of the persons selected had likely metabolically significant vitamin B-12 deficiency. Higher MMA concentrations were associated with lower MMSE scores independent of age and education (P = 0.007). MMA concentration correlated inversely with CAMCOG scores of ideational praxis (P < 0.05) and language comprehension (P < 0.05) and expression (P < 0.01). Serum folate correlated weakly but significantly with language (P < 0.05), remote memory (P < 0.05), and constructional and ideational praxis scores (P < 0.05 and P < 0.01, respectively).

CONCLUSION:

The high prevalence of likely metabolically significant vitamin B-12 deficiency in the elderly is associated with lower cognitive function scores and particularly with lower scores of language comprehension and expression.

• Authors: Cherie McCracken, Peter Hudson, Richard Ellis, Andrew McCaddon, Medical Research Council Cognitive Function and Ageing Study
• Journal: The American journal of clinical nutrition (Am J Clin Nutr) Vol. 84 Issue 6 Pg. 1406-11 (Dec 2006) ISSN: 0002-9165 [Print] United States
• PMID: 17158424 (Publication Type: Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't)

Chemical References

• Vitamin B Complex
• Methylmalonic Acid
• Folic Acid

Topics

• Aged
• Aged, 80 and over
• Aging (blood, physiology)
• Cognition (physiology)
• Cohort Studies
• Cross-Sectional Studies
• Female
• Folic Acid (blood)
• Folic Acid Deficiency (complications, diagnosis, epidemiology)
• Geriatrics
• Humans
• Language Tests
• Longitudinal Studies
• Male
• Methylmalonic Acid (blood)
• Vitamin B 12 Deficiency (complications, epidemiology)
• Vitamin B Complex (blood)