Objective To quantify in-hospital systolic blood pressure variability among patients with intracerebral hemorrhage, determine the association between high systolic blood pressure variability (HSBPV) and 90-day severe disability or death, and examine the association between pre-hospital factors and HSBPV. Methods Adult, radiologically confirmed, intracerebral hemorrhage patients enrolled in a multi-site cohort were included. Using a semi-automated algorithm, systolic blood pressure values recorded from routine non-invasive systolic blood pressure monitoring in critical and acute care settings were extracted for the duration of hospitalization. Inter and intra-patient systolic blood pressure variability was quantified using generalized estimating equation methods. Modified Poisson and logistic regression models were fit to determine the association between HSBPV and 90-day severe disability or death and between pre-hospital characteristics and HSBPV, respectively. Results A total of 566 patients managed at four certified stroke centers were included. Over 120,000 systolic blood pressure readings were analyzed, and a standard deviation (SD) of 13.0 was parameterized as a cut-off point to categorize HSBPV. Patients with HSBPV had a greater risk of 90-day severe disability or death (relative risk: 1.20, 95% confidence interval: 1.04–1.39), after controlling for age, pre-morbid functional status, and other disease severity measures. Greater likelihood of in-hospital HSBPV was independently observed in elderly, female patients, and in patients with high admission systolic blood pressure. Conclusion Quantification of HSBPV is feasible utilizing routinely collected systolic blood pressure readings, and a singular cut-off parameter for systolic blood pressure variability demonstrated association with 90-day severe disability or death. Elderly, female, and patients with high admission systolic blood pressure may be more likely to demonstrate HSBPV during hospitalization.
Response by Ziai et al to Letter Regarding Article, “Blood Pressure Variability Predicts Poor In-Hospital Outcome in Spontaneous Intracerebral Hemorrhage”