Serum homocysteine level is positively associated with chronic kidney disease in a Taiwan Chinese population.

BACKGROUND: Both hyperhomocysteinemia and chronic kidney disease (CKD) increase risk of cardiovascular disease. In this study, we investigated the association between serum homocysteine level and CKD.

MATERIALS AND METHODS: A total of 1,581 participants were recruited from a health check-up center in a tertiary hospital in Taiwan between 2006 and 2008. Two groups were created based on serum homocysteine levels above or below 12.24 μmol/l. Estimated glomerular filtration rate (eGFR) was calculated by the Modification of Diet in Renal Disease equation; we defined CKD as an eGFR below 60 ml/min/1.73 m(2). Multivariate logistic and linear regression analyses were used to estimate the associations between serum homocysteine levels and kidney function.

RESULTS: Subjects with elevated homocysteine levels were older and had higher body mass index, blood pressures, fasting plasma glucose, total cholesterol, triglycerides, and eGFR than those with normal serum homocysteine level. Using multiple logistic regression analyses after adjustment for age, sex, lifestyle habits (smoking, alcohol consumption, and betel nut chewing) and chronic diseases (hypertension, diabetes, dyslipidemia), the odds ratio (95 % confidence interval) of having CKD was 5.76 (2.99-11.1) among subjects with elevated serum homocysteine levels compared to subjects with normal serum homocysteine levels. The significant increase in odds ratios for CKD in progressive homocysteine levels reveals a dose-response effect. After adjustment for confounders, at multiple linear regression analyses serum homocysteine level resulted significantly and negatively correlated to eGFR.

CONCLUSIONS: Elevated serum homocysteine levels appear to be closely associated with CKD. Serum homocysteine levels are negatively associated with eGFR.