Abstract TP429: Predictors of Increased Blood Pressure Variability in Acute Intracranial Hemorrhage: A Secondary Analysis of the ATACH-2

Introduction: Increased blood pressure variability (BPV) is associated with worse neurologic outcome in patients with acute intracerebral hemorrhage (ICH). However, studies have shown that accurate measurement of BPV requires over 50 blood pressure readings, during which patients may be exposed to the deletrious effects of increased BPV. Hypothesis: Clinical variables will accurately predict BPV in patients enrolled in the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-2) trial. Methods: This is a secondary analysis of ATACH-2. Our primary outcome is the top quintile of the standard deviation of systolic blood pressure (SBP SD), which was calculated using all available blood pressures after the first 2 hours, with a mean of 56 blood pressures per patient. With stepwise backwards selection and an interactive process, we selected demographic variables that best predicted the top quintile. Results: We included 946 patients, of which 360 (38.1%) were female and the mean±SD age was 61.8±13.0 years. After exploring multiple combinations of baseline demographics, the best model included non-asian (vs. asian), intubation, and female sex as the predictors. This resulted in an area under the receiver operating curve of 0.772 (Figure 1). We created a scoring system (Table 1). With a score of ≥4, there is 79% sensitivity and 60% specificity for determining the top quintile of SBP SD. Conclusion: This pilot study identifies several easily determined clinical variables which, with further refinement and validation, could be used to identify patients at risk of the highest levels of BPV after ICH, and potentially to administer treatment to reduce BPV.