Abstract: Objective To compare the sensitivity of mini-mental state examination (MMSE), and Montreal cognitive assessment (MoCA) for the diagnosis of cognitive impairment in maintenance hemodialysis (MHD) patients, and to explore the characteristics of cognitive impairment in MHD patients. Methods A total of 89 MHD patients were examined with MMSE and MoCA between Oct. 2015 to Jan. 2016, and at the same time their cognitive impairment was assessed by neurologists. We then evaluated the specificity and sensitivity of MMSE and MoCA for the diagnosis of cognitive impairment in these patients. Results For the diagnosis of cognitive impairment, the sensitivity was 30.23% and the specificity was 100% by MMSE, and the sensitivity was 97.67% and the specificity was 76.32% by MoCA. The patients diagnosed with cognitive impairment had lower scores in attention and calculation (t=- 4.995, P=0.000), retelling ability (t=- 2.284, P=0.021), reading ability (t=-2.322, P=0.023), writing ability (t=-4.156,P＜0.001), and construction (t=-3.921, P＜0.001) by MMSE, and had lower scores in visual-spatial and executive capacities (t=-4.636, P＜0.001), attention and calculation (t=-5.654, P＜0.001), language (t=-9.214, P＜0.001), abstract ability (t=-4.910, P＜
0.001), and delayed recall ability (t=-2.306, P=0.024) by MoCA, as compared those with the patients without cognitive impairment. Conclusions The sensitivity of MoCA was higher than that of MMSE for the diagnosis of cognitive impairment in MHD patients. The patients diagnosed with cognitive impairment had lower
scores in some specific executive abilities such as executive capacity,attention,construction,and abstract ability.

Key words: cognitive impairment,  Mini-mental state examination,  Montreal cognitive assessment, diagnosis sensitivity