Hyperhomocysteinemia increases the risk of chronic kidney disease in a Chinese middle-aged and elderly population-based cohort

Background Patients either with hyperhomocysteinemia or chronic kidney disease (CKD) have an increased risk of cardiovascular disease. Little is known regarding whether hyperhomocysteinemia can increase the risk of CKD in a Chinese middle-aged and elderly population. To help clarify this we conducted a prospective cohort study to measure the association of hyperhomocysteinemia with CKD. Methods A total of 5917 adults aged 56.4 +/- 9.6 years without CKD at baseline were enrolled. The highest homocysteine quartile (ae<yen>15 mu mol/L) was defined as hyperhomocysteinemia. CKD was defined as decreased estimated glomerular filtration rate (eGFR < 60 mL/min/1.73 m(2)) or presence of proteinuria (urine protein ae<yen> 1+) assessed using a repeated dipstick method. Results During 3 years of follow-up, 143 (2.4%) patients developed CKD, 85 (1.4%) patients with proteinuria and 59 (1.0%) patients with decreased eGFR. After adjusted for potential confounders, both homocysteine (per 1 mu mol/L increase) and hyperhomocysteinemia were independently associated with increased risk of decreased eGFR [with a fully adjusted OR of 1.07 (95% CI 1.04-1.10) and 3.05 (95% CI 1.71-5.46)] and CKD [with a fully adjusted OR of 1.04 (95% CI 1.02-1.07) and 1.62 (95% CI 1.11-2.35)], respectively. By contrast, neither homocysteine (per 1 mu mol/L increase) nor hyperhomocysteinemia were associated with proteinuria in the multivariable logistic regression analysis. Conclusions The study revealed that hyperhomocysteinemia increases the risk of decreased eGFR. This suggests that homocysteine could be considered as a useful molecular markers for delaying the development of CKD.