Abstract: Objective  To evaluate cognitive function and potential risk factors in patients with chronic kidney disease (CKD). Methods  Totally 132 patients from Beijing Tiantan Hospital, Capital Medical University were included in this study, and they were divided into four groups according to CKD criteria and estimated glomerular filtration rate (eGFR) levels: healthy participants (n=25), mild CKD ［(eGFR ≥ 60 mL·min^-1·(1.73 m2)^-1］ group  (n=51), moderate to severe CKD ［eGFR<60 mL·min-1·(1.73 m2)^-1］ group  (n=34), and CKD hemodialysis group (n=22).  The participants had a median eGFR of 94.0  mL·min^-1·(1.73 m2)^-1, with an average age of (55.3 ± 14.0) years. Clinical characteristics of the patients were compared between 4 groups. Cognitive function was assessed with the Montreal Cognitive Assessment (MoCA). Furthermore, sleep breathing monitoring was performed on the included participants, including sleep apnea Hypopnea index (AHI) and oxygen reduction index (ODI), The statistical analysis was done with morpheus ox software. Analysis of variance and Chi-squared test were used to compare differences between groups. The correlation and cognitive-related risk factors were determined by logistic regression analysis. Results  Compared with healthy control group, MoCA scores decreased with renal function deterioration, and the impairment of executive function was more severe (P<0.01). The multivariate logistic regression analysis results suggested that low hemoglobin (OR＝0.97, 95% CI： 0.95-0.99) and age (OR＝1.10, 95% CI： 1.05-1.15) might be risk factors for cognitive impairment in CKD patients. Conclusions  CKD patients might show cognitive impairment with a decrease of eGFR levels, and clinical symptoms could be more severe in these patients.  Low hemoglobin and age may be risk factors accounting for cognitive impairment in CKD patients.

Key words: cognitive function, chronic kidney disease, estimated glomerular filtration rate, Montreal Cognitive Assessment