Objective      To investigate the relationship between blood pressure in acute phase of ischemic stroke and post-stroke cognitive impairment (PSCI).       Methods      Seven hundreds and ninety six patients with first onset of acute ischemic stroke hospitalized within 24 h were recruited in this study. The average systolic blood pressure (SBP) or diastolic blood pressure (DBP) within 7 d of onset was defined as SBP or DBP at acute phase. The patients with cognitive impairment were judged as Montreal cognitive assessment (MoCA)26 points. The MoCA scores and the prevalence of cognitive impairment at admission

14 d

and 3

6

and 12 months were dynamically analyzed

and the blood pressure value at acute phase was quintile (Q1~Q5). A multiple parameter logistic regression analysis was conducted to determine the relationship between blood pressure levels at acute phase and the MoCA scores measured at 3 months after onset.       Results      The prevalence of PSCI was highest (78.91%) at 3 months after stroke

and gradually decreased after each time point. Taking Q3 group as a reference

the risk of PSCI was the highest (OR=1.83

95% CI:1.64~2.28

P=0.007) in Q1-SBP (102~127 mmHg) and was also the highest (OR=2.32

95% CI:1.74~2.90

P0.001) in Q5-SBP (170~215 mmHg). Mean blood pressure

DBP and SBP had similar characteristics.       Conclusion      Too high or too low blood pressure level at acute phase of ischemic stroke is the predictor of PSCI

and remaining the blood pressure at rational level may help to reduce the risk of PSCI.