Abstract T P72: Baseline Variables Have Little Influence on Early Change in Neurological Status (ΔNIHSS) After Acute Ischemic Stroke: Basis For a Genetic Study

Abstract

Introduction: Neurological deficits can be highly unstable within the first 24 hours after acute ischemic stroke (AIS), with some patients showing dramatic improvement while others rapidly deteriorate. We are interested in genetic influences on early neurological recovery/deterioration. Here, we characterize NIHSS changes within the first 24 hours after stoke onset (ΔNIHSS) in a large cohort to determine baseline clinical variables that influence this outcome measure. Methods: AIS patients presenting to two sites (Barnes-Jewish Hospital, St Louis and Vall D’Hebron Hospital Barcelona) between 2008-2013 were prospectively enrolled. Baseline NIHSS was collected within 6 hours and again at 24 hours after symptom onset. ΔNIHSS was calculated as the difference in these stroke scale scores. Demographics, baseline comorbidities and medications, as well as acute treatment variables were recorded for each subject. Stepwise multivariable regression (SAS) was used to determine variables that significantly influence ΔNIHSS. Results: There were 954 patients enrolled (St Louis = 433, Barcelona = 521). Table 1 demonstrates the frequencies and means (SD) of the baseline variables. ΔNIHSS follows a normal distribution (figure). All baseline variables listed in table 1 were analyzed for influence on ΔNIHSS. Only baseline NIHSS (R2 = 0.0597, p<0.0001), baseline glucose (R2 = 0.0176, p=<0.0001,) and age (R2 = 0.0106, p=0.0011) independently influenced ΔNIHSS, accounting for only 8.79% of the variance. Conclusion: Baseline variables (NIHSS, glucose and age) modestly influence early neurological recovery/deterioration. However, 91% of ΔNIHSS variability remains unexplained, suggesting that other factors such as genetics, could play an important role in early outcomes following AIS. A GWAS of ΔNIHSS is currently underway.