Prevalence of hyperhomocysteinaemia in a Chinese elderly population

Objective: To evaluate plasma homocysteine (Hcy) levels and prevalence rates of hyperhomocysteinaemia (HHCY) in elderly Chinese individuals. Design: A cross-sectional study. Setting: The study was conducted in 2006 in two counties from the north and the south of China. Subjects: A total of 810 individuals aged 65-74 years were recruited. Demographic characteristics and lifestyle factors were assessed through questionnaire interviews and physical examination. Hcy and folate levels were measured in blood samples. The distribution of Hcy level was analysed according to Hcy-related factors. Results: Northerners had higher Hcy levels (18.42 mu mol/l) than southerners (10.20 mu mol/l). Plasma Hcy was higher in men than in women and greater in smokers than in non-smokers. The prevalence rate of HHCY was 51.6% in the north and 10.1% in the south (P<0.001). Hcy and plasma folate showed an inverse correlation (Spearman's r=-0.44, P<0.001; partial r=-0.229, P<0.001). Region, gender, alcohol consumption and plasma folate were associated with HHCY among these elderly populations. Conclusions: The results demonstrated that plasma Hcy levels and the prevalence rates of HHCY in Chinese elderly are considerably higher than those found in other countries, and substantial regional variations occur within China. The predominant determining factors of HHCY were region, gender, alcohol consumption and plasma folate. The elevated Hcy levels among elderly Chinese populations need to be decreased urgently.