Blood Levels of Homocysteine Predict Cardiovascular Events, but not Alzheimer Disease Dementia, During a 4.7-year Follow-up in Patients with Vascular Risk Factors

Aims The homocysteine levels are risk factors for vascular events and dementia. However, whether their predictive validity is similar remains unknown. We compared the utility of the homocysteine levels for predicting vascular events and Alzheimer's disease (AD) and dementia in the same population. Methods This study was a Japanese hospital-based cohort study. A total of 426 patients with vascular risk factors were followed for a median of 4.65 years. Based on the homocysteine levels, patients were divided into three groups: 1st tertile (<8.2 nmol/L, n=141), 2nd tertile (8.3-10.9 nmol/L, n=141), and 3rd tertile (>11.0 nmol/L, n=144). They were also divided with the cut-off value of 15.0 nmol/L into high (n=55) and low (n=371) groups. The outcomes were stroke, major cardiovascular events (MACE), and AD dementia. Results During follow-up, stroke, MACE, and AD dementia occurred in 23, 31, and 15 patients, respectively. Patients in the 3rd tertile and high groups were more likely to have incident stroke and MACE than those in the other tertiles or low group. Patients with high homocysteine levels had a higher risk of stroke (hazard ratio 3.59; 95% confidence interval 1.09-11.83) and MACE (hazard ratio 5.19; 95% confidence interval 1.90-14.15) than those with low homocysteine levels after adjustment for confounding factors. However, no association was observed between the homocysteine levels and AD. Conclusion High serum homocysteine levels, especially more than 15.0 nmol/L, were significantly associated with vascular events but not with AD dementia in the same population during a 4.65-year follow-up period.