Abstract: Objective To investigate the relationship between serum homocysteine (Hcy) and cognitive impairment(CI) in elderly patients with hemodialysis (HD). Methods A total of 107 HD patients were divided into normal cognition group and cognitive impairment group according to the evaluation of Montreal Cognitive Assessment (MoCA). Clinical data including serum Hcy level were collected in the two groups. Relevant indicators were compared between the two groups, and the relationship between cognitive impairment and serum level of Hcy was analyzed by multivariate Logistic regression.Receiver operating characteristics (ROC) curve was also plotted to evaluate the diagnostic value of Hcy for the cognitive impairment. Results Seventy(65.4%) of 107 HD patients suffered from cognitive impairment. There were significant differences in MoCA scores, age, gender, education level, stroke history, heart disease history, dialysis duration, hemoglobin and homocysteine levels between the two groups (P＜0.05). Multivariate Logistic regression showed that the increased levels of hemoglobin in male were protective factors for cognitive impairment. The odd ratio (OR) and 95% confidential interval (95%CI) were 0.295 (0.095-0.916) and 0.952 (0.910-0.997，P＜0.05). Age, prolonged dialysis and elevated serum Hcy level were risk factors for cognitive impairment. The OR values (95%CI) were 1.080 (1.026-1.136), 1.022 (1.008-1.036) and 1.212 (1.039-1.414), respectively（P＜0.05). The area under curve of ROC analysis was 0.711 (0.611-0.811), the cut-off point of serum Hcy under the maximum Youden index was 20.65 μmol/L, the sensitivity was 65.7% and the specificity was 56.8%. Conclusion Cognitive impairment is common in hemodialysis patients. It might be associated with gender, age,dialysis duration and anemia. High serum level of Hcy is also an independent risk factor for cognitive impairment, which may be an effective index for predicting cognitive impairment.

Key words: renal dialysis, cognition disorders, homocysteine, aged