Homocysteine as a risk factor for cognitive impairment in stroke patients

Background. Elevated total homocysteine (tHcy) levels are associated with an increased risk of cerebrovascular disease. It is uncertain whether tHcy is also an independent risk factor for cognitive impairment. Methods: We examined 95 stroke subjects 3 months after their strokes, and 55 healthy comparison subjects, with a detailed neuropsychological assessment, and MRI brain scans in a proportion (n = 97). Baseline measurements of tHcy, serum folate and B-12, creatinine and plasma fibrinogen levels were obtained. Results: tHcy levels were higher in the stroke subjects by a mean 34%. These levels were significantly correlated with the first factor of a principal component analysis of the neuropsychological data, after controlling for age, folate, B-12 and creatinine levels. The correlation of Hey levels was particularly significant with frontal-executive functioning and attention. tHcy levels were significantly correlated with number of infarcts and total stroke volume in the stroke group, but not with T-2-weighted deep white matter hyperintensity scores, after correction for age. In the control group, tHcy levels were significantly correlated with ventricle-to-brain ratios as measures of brain atrophy. Conclusion: This study provides evidence that high tHcy levels are associated with cognitive impairment, in particular that of frontal-executive function. The major component of this association is accounted for by small and large strokes, but non-vascular neurotoxic effects of tHcy also appear to play a role. tHcy must receive greater attention as a risk factor for cognitive impairment. Copyright (C) 2003 S. Karger AG, Basel.