Homocysteine, cerebrovascular disease and brain atrophy.

Homocysteine (Hcy) is known to increase the risk of cerebrovascular disease (CVD). Recent evidence suggests its direct contribution to brain atrophy, cognitive impairment and possibly Alzheimer disease (AD). This paper reports the results of two studies of the impact of Hcy on the brain. In the Sydney Stroke Study (N=131 stroke patients, 81 healthy controls), higher Hcy levels were related to increased number of strokes and greater cognitive impairment, in particular, frontal-executive function and attention. In the control group, Hcy was related to increased subcortical atrophy. In the PATH Through Life Study, involving 60-64 years old community-dwelling individuals (N=385), Hcy was related to an increase in white matter hyperintensities, as well as impairment in verbal memory and fine motor speed. Hcy increases the risk of micro- and macrovascular disease as well as brain atrophy, and thereby impaired cognition. Remediation of high Hcy levels should begin early in life.