Is spontaneous normalization of systolic blood pressure within 24 hours after ischemic stroke onset related with favorable outcomes?

BACKGROUND: In acute ischemic stroke, blood pressure (BP) tends to rise initially and fall to a baseline level within 24–48 hours. Previous studies reported several different effects of BPs during acute ischemic stroke on clinical outcomes, which was partly due to the different time intervals from stroke onset to BP measurement. METHODS: All patients with acute ischemic stroke (onset ≤3 hours) who lived independently before the stroke, were consecutively enrolled for a 62-month period. BPs at 0, 12, and 24 hours after admission were collected. A favorable outcome was defined as a modified Rankin Scale (mRS) score 0–2 at discharge. For different standards of BP management, patients were grouped and analyzed according to intravenous (IV) tissue plasminogen activator (tPA) treatment and favorable outcome. RESULTS: Among the 446 enrolled patients, 227 patients underwent IV tPA treatment and 216 had mRS score 0–2 at discharge. Patients with favorable outcomes had lower initial NIH Stroke Scale (NIHSS) scores, less frequent progressive neurological deficits, and lower systolic BP (SBP) 12 and 24 hours after admission than patients with unfavorable outcomes, regardless of whether they underwent tPA treatment or not (p <0.05). The BP decreased over a period of 24 hours after admission. In logistic regression analysis, the independent variables associated with favorable outcome were the initial NIHSS score, a progressive neurological deficit, a previous stroke, and the SBP 24 hours after admission in the patients who underwent tPA treatment and the initial NIHSS score and a progressive neurological deficit in the patients who did not undergo tPA treatment (p <0.05). CONCLUSIONS: The SBPs at 12 and 24 hours after admission were lower in acute stroke patients with favorable outcomes than in the other patients, regardless of whether the patients underwent tPA therapy and the SBP at 24 hours was an independent predictor of favorable outcomes among the patients who underwent tPA treatment.