Abstract TMP50: Increased Systolic Blood Pressure In The Subacute, But Not Acute, Period After Ischemic Stroke Is Associated With Good Functional Outcome At 90 Days

Abstract

Background: Prior research has shown that increased blood pressure variability (BPV) after ischemic stroke is associated with lower odds of good functional outcome, but the number, intervals between, and epochs of blood pressure measurements have not been standardized. Methods: We include patients enrolled in the FAST-MAG trial with a final diagnosis of ischemic stroke, premorbid modified Rankin Scale (mRS) of 0, 4 “early” blood pressure measurements (prehospital and 3 in the hour after arrival), and 9 “later” measurements (q4 hours from hours 4-24 and q8 hours from hours 24-48). The primary outcome was 90-day mRS of 0-1 (good outcome). The BPV exposure was the top tertile (highest level) of systolic standard deviation (SD). We fit logistic regression models adjusted for patient age, race, sex, baseline NIH Stroke Scale, tPA, endovascular therapy, mean systolic blood pressure, smoking, atrial fibrillation, hypertension, and diabetes. Results: We included 455 patients, with a mean age of 70.8 years, 46.8% female, 50.8% had tPA, 6.4% had endovascular therapy, the median baseline NIH Stroke Scale was 12 (5-19) and good outcome occurred in 152/455 (33.4%). The mean early SD was not significantly lower in patients with good outcome (p=0.12), but later SD was lower in patients with good outcome (13.5±5.6 vs. 15.1±5.6, p<0.01). The adjusted odds ratio for good outcome in the top tertile of early BPV was 1.09 (95% CI 0.63-1.89), while for the top tertile of later BPV it was 0.54 (95% CI 0.30-0.95). The predicted probability of good outcome for a range of later BPV values is seen in Figure 1. Conclusion: Increased BPV in the hours after ischemic stroke onset was not associated with 90-day good outcome, but increased BPV during hours 4-48 after hospital arrival had a significant association with lower odds of good outcome. While these results are hypothesis-generating, the rigor of outcome adjudication and standardization of blood pressure measurements strengthens the findings.