Change In Blood Pressure And Its Relation With Prognosis Of Acute Stroke

Objectives: 1.To investigate the change in blood pressure(BP) of patients with acute stroke and independent factors related to BP levels. 2. To evaluate the relationship between BP in acute stage and the prognosis. Methods: From March 2002 to March 2004, all inpatients with acute stroke consecutively admitted to the neurological wards of West China Hospital Sichuan University, were prospectively registered. The patients with ischemic and hemorrhagic stroke within 24 hours were included in this study. BP was measured at 4-h intervals during the first 48h, at least twice daily from day 3 to discharge. BP changes of patients within 6 hours from admission to 15days were observed. Changes were assessed in relation to stroke type,antihypertensive treatment and initial stroke severity. All subjects were followed up at l~st,3~rd,6~th and 12~th month after ictus. The outcome measure was death,dependency(BI≤60) and recurrence. Multivariate linear regression model was used to analyze independent relations to admission BP. Logistic regression was used to estimate the relationship between BP and prognosis. Results: 1.A totle of 1322 patients with acute stroke were registered, and 592 patientswere included. 53.7% of patients had known history of hypertension, the BP range on admission was 72~280/42~180mmHg(mean±SD,151 ±29/ 90± 18mmHg). 415 patients (70.1%) had elevated BP(SBP^140mmHg and/ or DBP^90mmHg). 279 patients (47.1%) received antihypertensive drug during the hospital stay.2. In 311 patients with stroke within 6h, mean admission BP was 156 + 31/93 +19mmHg . There were marked falls in SBP and DBP levels during the 12hours later(l38±24/81 ± 15mmHg),with little change thereafter. Bp at day 8was not different from 15d in paired-t test.3. Patients with hemorrhagic stroke had significantly higher SBP and DBP than those with ischemic stroke, throughout 15 days. The BP at day 4 after admission reached a stable level in a selected group with ischemic stroke. In hemorrhagic stroke,BP at day 8 reached a stable level. Patients continuing with or started on antihypertensive medicine after stroke had significantly higher SBP and DBP than those on no medication.Mean BP on admission in the former was 165 + 29/ 98±18mmHg and in the latter 145 ± 26/86 ± 16mmHg, and by day 15 no significant differences in BP could be detected among treated and untreated patients. Patients with mild to moderate stroke showed no difference in BP profile from those with severe stroke. 4.1ndependent factors related to SBP were: cardiac disease(-14mmHg),known hypertension priorto stroke(llmmHg),impaired conscious level(6rnrnHg), hemorrhagic stroke(6mmHg),age(3mmHg/l0-year increase); independent factors related to DBP werexardiac disease(-5mmHg),known hypertension prior to stroke(5mmHg), hemorrhagic stroke (6mmHg),diabetes(-6mmHg). 5.A U-shaped relationship was found between BP and early and late deathand death/dependency. Both high and low SBPand DBP values are associated with a poor prognosis. The cutoff levels were set at 120 and 90 mmHg or so for SBPand DBP on admission, 140 and 90mmHg for SBP and DBP on day 1-8. ?The independent predictors of death at lstmonth were reductions in SBP and DBP during 1st day (OR 1.450/SBP drop 20mmHg, 95%CI 1.049— 2.003; OR 1.907/dbp drop 20mmHg, 95 % CI 1.348 — 2.698) .?The independent predictors of death at 3ldmonth were reductions in DBP during 1st day(OR 1.720/DBP drop 20mmHg, 95%CI 1.215—2.436) and SBP on admission(OR 3.23I/for every lOmmHg ?S 120mmhg of SBP, 95 % CI 1.107 — 9.429) ?The independent predictors of death at 6thmonth were reductions in DBP during 1st day(OR 1.486/DBP drop 20mmHg, 95%CI 1.061-2.081) and DBP on day 4.7.8 (OR 1.208-1.331/for every 5mmHg < 90mmHg of DBP,p<0.05).6.The blood pressure during acute stroke did not appear to predict independently the death/dependency after stroke. Conclusions: 1. There were marked fall in BP levels during the 12hours later, with little change thereafter. BP at day 8 reached a stable level . 2. Higher SBP and DBP was seen in patients with hemorrhagic stroke than those with ischemic stroke, throughout 15 days. The Bp at day 4 after admission reached a stable level in patients with ischemic stroke,and at day 8 in those with hemorrhagic stroke.Patients receiving antihypertensive medicine after stroke had significantly higher SBP and DBP levels up to day 15 than those on no medication. Initial stroke severirty did not appear to alter the BP patter. 3. SBP and DBP on admission was significantly decreased in patients with cardiac disease.Patients with known hypertension prior to stroke and patients with hemorrhagic stroke had a significantly increased SBP and DBP onadmission. SBP—but not DBP--was significantly increased in patients with impaired conscious levels and increase in age. DBP—but not SBP—was significantly decreased in patients with diabetes. 4. A U-shaped relationship was found between BP and early and late death and death/dependency. Both high and low SBP and DBP values are associated with a poor prognosis. Reductions in BP during lstday were the independent predictors of death at l-month,3-month,6-month. Bp during 8 days after acute stroke affected independently death at 6- month. The blood pressure during acute stroke carried the best prognosis was 140/90mmhg or so. The BP did not appear to predict independently the death/dependency after stroke.