Blood pressure fluctuation pattern and stroke outcomes in acute ischemic stroke

Blood pressure (BP) fluctuates widely during the acute phase of stroke. Compared to single BP assessment, patterns of BP over time may have greater power in predicting stroke outcome. This study aims to investigate the effect of BP fluctuation patterns on stroke outcomes in acute ischemic stroke (IS) patients. IS patients within 24 h of onset registered in the BOSS registry between 2012 and 2014 were analyzed. Fluctuation of BP was predefined as the change trend in systolic BP (SBP) from Day 1 to Day 7 after onset and was used to divide patients into groups with sustained high SBP (>= 160 mmHg) during the first 7 days (C1); rapid (C2: within the first 2 days) or delayed (C3: after 2 days) decline from high (>= 160mmHg) to low (<160mmHg); consistently low SBP (C4); and elevation from low to high (C5). The primary stroke outcome was defined as a modified Rankin Scale score >= 3 at 3 months after onset. Of 1,095 IS patients, C1 (n= 90) had the highest risk of poor outcome (23.3%), while C2 (n= 198, risk= 11.6%) and C4 (n= 650, risk= 12.2%) had the lowest risk. C2 and C4 had a significant reduction in poor outcome risk when compared to C1, even after adjustment for average BP and BP variability (BPV) during the first 7 days (adjusted odds ratio [OR](C2)= 0.32, 95% CI: 0.12-0.80; ORC4= 0.37, 95% CI: 0.14-0.97). The BP fluctuation pattern in the acute phase of IS might be a useful predictive parameter for functional outcome independent of average BP and BPV.