Article

Heterozygote advantage of the MTHFR C677T polymorphism on specific cognitive performance in elderly Chinese males without dementia.

Department of Psychiatry, Taipei Veterans General Hospital, Taiwan, ROC.
Dementia and Geriatric Cognitive Disorders (impact factor: 2.14). 01/2011; 32(3):159-63. DOI:10.1159/000333074 pp.159-63
Source: PubMed

ABSTRACT Aging is associated with cognitive deterioration, and genetic factors are implicated in individual cognitive differences in the aged. The C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene (MTHFR) yields a common thermolabile variant (T) with reduced enzyme activity and consequent elevation of serum homocysteine concentrations. We designed the present study to investigate whether this functional polymorphism may affect global and specific cognitive functions in older Chinese males without dementia.
The subjects included 356 elderly males without major psychiatric disorders or dementia, who were assessed by the Cognitive Abilities Screening Instruments (CASI) and the Wechsler Digit Span Task tests.
A significant association was found between the MTHFR C677T polymorphism and total CASI scores (p = 0.012), particularly in short-term memory (p = 0.002) and concentration/mental manipulation (p = 0.007). Post hoc tests indicated that the C/T heterozygotes achieved better cognitive function test results than C/C or T/T carriers. No association was found between the MTHFR genotype and the Wechsler Digit Span Task tests.
These results suggest that a heterozygote advantage exists for the MTHFR C677T polymorphism in specific cognitive functions in elderly Chinese males without dementia.

0 0
 · 
0 Bookmarks
 · 
43 Views
  • Source
    Dataset: Low and high homocysteine are associated with mortality independent of B group vitamins but interactive with cognitive status in a free-living elderly cohort
    Guipu Li, Andrew J Sinclair, Duo Li
  • Source
    Article: Low and high homocysteine are associated with mortality independent of B group vitamins but interactive with cognitive status in a free-living elderly cohort.
    Li-Li Xiu, Meei-Shyuan Lee, Mark L Wahlqvist, Rosalind Chia-Yu Chen, Yi-Chen Huang, Kuan-Ju Chen, Duo Li
    [show abstract] [hide abstract]
    ABSTRACT: Hyperhomocysteinemia and cognitive impairment both predict mortality and partly because of dietary associations. We have hypothesized that for, nutritional reasons, homocysteine and cognition may act jointly to determine elder survival. In a Nutrition and Health Survey in Taiwan (1999-2000), some 1412 representative elderly were followed up for mortality up to 10 years. Cognition was assessed by the Short Portable Mental Status Questionnaire. Food and B vitamin intakes with their biomarkers, and plasma homocysteine, were measured at baseline. The possible effects of cognition on homocysteine-associated mortality were ascertained with Cox proportional-hazards models. Homocysteine was higher in those who were older, male, and single, consumed less fish and tea, and with alcohol and smoking. In models adjusted for these variables, when homocysteine exceeded 14.5 μmol/L, mortality was 1.80-fold more than when <9.3 μmol/L (hazard ratio [HR], 1.80; 95% confidence interval [95% CI], 1.20-2.71). P for trend was 0.002 and interactive with sex (P < .002). However, these homocysteine-mortality associations were dependent on cognition (P = .03); adjustment for food intake or nutrient status made little difference. Homocysteine did not predict cognitive impairment (adjusted OR, 1.40; 95% CI = 0.50-3.93). Vitamins B(1), B(2), and B(6) accounted somewhat for cognitive impairment. Cognition predicted mortality, fully adjusted for available covariates and also for homocysteine (HR, 3.66; 95% CI, 1.64-8.20) but interactively with homocysteine. Thus, the B-group vitamin insufficiency and cognitive impairment associations with premature mortality are confirmed. Yet cognition is inter-related with homocysteine in its association with survival in ways not detectably altered by foods or food-derived vitamins.
    Nutrition research (New York, N.Y.) 12/2012; 32(12):928-39. · 1.20 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

356 elderly males
 
Aging
 
C/T heterozygotes
 
Cognitive Abilities Screening Instruments
 
cognitive function test results
 
common thermolabile variant
 
dementia
 
enzyme activity
 
genetic factors
 
global
 
heterozygote advantage
 
major psychiatric disorders
 
serum homocysteine concentrations
 
short-term memory
 
significant association
 
T/T carriers
 
Wechsler Digit Span Task tests