Plasma homocysteine levels and atherosclerosis in Japan - Epidemiological study by use of carotid ultrasonography

Background and Purpose-We examined whether hyperhomocysteinemia is an independent risk factor for increased carotid artery intimal medial wall thickness (IMT) in a large randomly selected community in Japan where the dietary habit is different and the incidence of coronary artery disease is lower compared with those of western countries Methods-In 1111 cases (452 men 659 women) aged 63 +/- 10 years old (range 40 to 94 years) recruited from a population based survey performed in 1999 we measured fasting plasma total homocysteine levels and performed bilateral carotid B mode ultrasound The participants underwent measurements of other blood chemistries (total cholesterol HDL cholesterol glycosylated hemoglobin At and creatinine) Results-For the total population the mean total homocysteine level was 10 9 mumol/L Total homocysteine levels were higher in men than in women and increased with aging With multiple linear regression analysis after adjustments for age and sex the most powerful determinant of total homocysteine levels was serum creatinine (P<0 001) With multiple stepwise regression analysis after adjustments for age sex and other confounding factors total homocysteine was significantly (P<0 05) related to IMT Furthermore when mean values of IMT adjusted for age sex and other related factors were analyzed across total homocysteine quartiles IMT (P<0 05) showed a significant trend as total homocysteine level increased Conclusions-Plasma total homocysteine levels in Japan are similar to those reported in western countries Mild hyperhomocysteinemia is an independent risk factor for increased carotid artery wall thickness in Japan as well.