Homocysteine and cognitive impairment in Thai elderly

Background: The prevalence and incidence of dementia increase dramatically with age. Cognitive impairment is one major symptom of dementia. Older persons increase in our society, which means a big number of people with decreased cognitive function. So it is important to find out risk factors. The amino acid homocysteine may be a risk factor. Objective: The aim was to determine the independent association of homocysteine and cognitive performance in Thai elderly. Design: Concentrations of homocysteine were measured in fasting blood samples of 100 Thais aged 60 – 80 years. Global cognitive function was assessed by using with mini-Mental State Examination score (MMSE), and cognitive functions were assessed by a neuropsychological test battery. The relationship between homocysteine levels and neuropsychological test scores was assessed by multiple linear regression. Results: In the crude model, homocysteine was inversely associated with scores for learning slope test (B = −0.048, p = 0.042) and verbal pair total test (B = −0.124, p = 0.032). After adjusting for confounders, no association was found between homocysteine and cognitive impairment. Age (B = −0.129, p = 0.007) was found to be a significant determinant of decreased learning slope score. Similarly, age (B = −0.298, p = 0.009) and education (B = 0.267, p = 0.029) were found to be significant determinants of decreased verbal pair total score. Conclusions: In this study, it was found that no association between homocysteine and cognitive impairment in a population of institutionalized subjects. Age and education were more significantly associated with cognitive impairment scores than homocysteine.

Keywords: Homocysteine, Cognitive Impairment, Thai.