Serum total homocysteine concentrations and risk of mortality from stroke and coronary heart disease in Japanese: The JACC study.

Evidence for association between serum total homocysteine (tHcy) level and cardiovascular disease is limited in Asian populations. We conducted a nested case-control study under JACC Study. A total of 39,242 subjects aged 40-79 years provided serum samples at baseline surveys between 1988 and 1990. Control subjects were selected by matching for sex, age, community and year of serum storage. Serum tHcy levels were measured by high-performance liquid chromatography. During the 10-year follow-up, there were 444 deaths due to total cardiovascular disease, including 310 total stroke (131 hemorrhage and 101 ischemic strokes) and 134 coronary heart diseases. The risks of mortality from ischemic stroke, coronary heart disease, and total cardiovascular disease were significantly higher in individuals with the highest serum tHcy quartile (>or=15.3micromol/L) than in those with the lowest quartile (<10.5micromol/L); the respective multivariable odds ratios (95% CI) were 4.35 (1.12-16.9), 3.40 (1.17-9.86), and 1.68 (1.02-2.77). The multivariable odds ratios associated with a 5-micromol/L increase in tHcy were 1.49 (1.01-2.18), 2.01 (1.21-3.35), and 1.15 (1.00-1.32), respectively. High serum tHcy levels were associated with increased mortality from ischemic stroke, coronary heart disease and total cardiovascular disease among Japanese.