Systolic blood pressure in acute ischemic stroke and impact on clinical outcomes

Abstract

Abstract Context Stroke is one of the largest healthcare burdens in the United States and globally. It continues to be one of the leading causes of morbidity and mortality. Patients with acute ischemic stroke (AIS) often present with elevated blood pressure (BP). Objectives The objective of our study was to evaluate the association of systolic blood pressure (SBP) in the emergency department (ED) with stroke severity in patients with AIS. Methods This observational study was conducted at an ED with an annual census of 80,000 visits, approximately half (400) of which are for AIS. The cohort consisted of adult patients who presented to the ED within 24 h of stroke symptom onset. BP was measured at triage by a nurse blinded to the study. Stroke severity was measured utilizing the National Institutes of Health Stroke Scale (NIHSS). Statistical analyses were performed utilizing JMP 14.0. This study was approved by our medical school’s institutional review board. Results Patients with higher SBP had significantly lower NIHSS scores (p=0.0038). This association was significant even after adjusting for age and gender. By contrast, diastolic blood pressure (DBP) did not appear to impact stroke severity. There was no difference in the DBP values between men and women. Higher SBP was also significantly associated with being discharged home as well as being less likely to die in the hospital or discharged to hospice. The DBP did not demonstrate this association. Neither the SDP nor the DBP were significantly associated with the hospital length of stay (LOS). In multivariate models that included age, gender, basal metabolic index (BMI), comorbidities, and ED presentation, elevated SBP was associated with better prognosis. Conclusions In this cohort of patients presenting with stroke-like symptoms to the ED, higher SBP was associated with lower stroke severity and higher rates of being discharged to home rather than hospice or death.