Acute-phase blood pressure trajectories and clinical outcomes in ischemic stroke

High blood pressure (BP) is frequent in acute ischemic stroke (IS). However, the impact of BP change patterns during acute phase on clinical outcomes is not conclusive. This study aims to investigate the association between the acute-phase BP trajectories and clinical outcomes in IS patients with high admission BP. The cohort consisted of 316 IS patients with admission systolic BP (SBP) ≥160 mm Hg. SBP trajectories during the first 7 days after onset were characterized using a random effects model. The patients were classified into three groups based on the SBP trajectory curve parameters: sustained high SBP (T1), moderate decrease (T2), and rapid decrease in SBP (T3). Poor outcomes were defined as modified Rankin scale score ≥3 in 3 months after onset. The relationship between SBP trajectory groups and the outcome was examined in multivariable logistic regression models. The decreasing trend was greater in the favorable than in the poor outcome group (P = 0.028 for difference in linear slopes). The incidence of poor outcomes was 25.9%, 13.5%, and 9.8% in T1 (n = 54), T2 (n = 170), and T3 (n = 92) groups, respectively. Compared with T1 group, the decrease in SBP in T2 and T3 groups was significantly associated with lower risk of the poor outcome (odds ratio = 0.25, 95% confidence interval = 0.10-0.67, P = 0.006). These findings suggest that a decrease in BP in the acute phase is predictive of favorable outcomes in IS patients. BP trajectories have a greater power to detect the association than individual BP values at one time-point.