Objective To assess whether elevated plasma homocysteine levels contribute to the risk of cardio-cerebrovascular mortality in a large prospective cohort of patients with first onset stroke in Chinese population.
Methods A total of 1,823 patients with first onset stroke(35-74 years) were recruited during 2000-2001, including 808 paitents with cerebral thrombosis, 513 paitents with lacunar infarction, and 502 patients with intracerebral hemorrhage. These stroke patients were followed up annually until May 31, 2006 by a standard questionnaire and telephone contact by physician investigators. Cox proportional-hazards models were used to examine the association between homocysteine(Hcy) and all-cause or cardio-cerebrovascular mortality.
Results During a median of 4.5-year follow-up, a total of 323 deaths from all causes were documented, including 183 deaths from recurrent stroke and coronary heart disease. After adjustment for age, sex, and conventional vascular risk factors, high Hcy level(≥16 μmol/L) was significantly associated with increased risk of all-cause mortality[relative risk(RR) 1.47, 95% confidence interval(CI) 1.15-1.88] as compared with lower Hcy level(<16 μmol/L). The association with all-cause mortality was mainly due to a positive association between homocysteine and the risk of cardiovascular deaths, and RR was 1.33(95%CI 1.06-1.65). Stroke subtype analysis showed that high Hcy level increased the risk of cardiovascular deaths not only in the patients with atherothrombotic stroke but also in those with hemorrhagic stroke.
Conclusion Our findings suggest that elevated plasma homocysteine levels are independently associated with increased risk of cardio-cerebrovascular mortality in the patients with first onset stroke.
