The comparison of cognitive function and risk of dementia in CKD patients under peritoneal dialysis and hemodialysis: A PRISMA-compliant systematic review and meta-analysis

BACKGROUNDS: Cognitive functions (CF) decline has been reported in end-stage renal disease (ESRD) patients. However, the influence of dialysis modalities on CF has not been investigated systematically. METHODS: A systematic literature search was conducted in MEDLINE, Embase, Cochrane library and unpublished database Clinicaltrials.gov to identify the studies comparing the cognitive functions or risk of dementia between hemodialysis (HD) and peritoneal dialysis (PD). After data extraction, quality of studies was assessed using the Newcastle-Ottawa scale. Both qualitative and quantitative analyses were performed. RESULTS: After study inclusion, totally 15 cohort or cross-sectional studies were included, comparing the cognitive functions using neuropsychological tests and covering the executive function, memory, orientation, attention, etc. By qualitative analysis, it showed that more studies are inclined to PD compared with HD with better cognitive functions. By quantitative analysis, it showed that PD showed better performance in the tests of Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), stroop interference test and exhibited lower risk of dementia compared with HD. CONCLUSIONS: In this meta-analysis, we draw preliminary conclusion that patients treated with PD had better cognitive functions and lower dementia risk compared with patients with HD. Still more large-scale and well-conducted prospective cohort studies are needed to draw more convincing conclusions.