Abstract DP329: Impact of white matter hyperintensity burden on response to induced hypertension therapy in small vessel occlusion stroke with early neurological deterioration

Introduction: Induced hypertension therapy (iHT) is an effective option for managing early neurological deterioration (END) in small vessel occlusion (SVO) stroke by enhancing collateral flow via perforating arteries. However, greater burden of white matter hyperintensity (WMH), reflecting chronic small vessel ischemia and perforator impairment, may indicate limited benefit from iHT. Thus, we investigated whether higher WMH burden is associated with poorer response to iHT. Methods: Consecutive patients with acute SVO stroke admitted between January 2017 and March 2025 were identified from a prospective stroke registry. Those who developed END within 7 days of onset and subsequently received iHT were included, with END defined as an increase of ≥2 points in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥1 point in the motor item. Total, periventricular, and deep WMH volumes were segmented and quantified from MRI FLAIR images using fully automated software. The primary outcome was responsiveness to iHT, defined as early neurological improvement (ENI; a decrease of ≥2 points in NIHSS or ≥1 point in the motor item within 48 hours after treatment). Secondary outcome was the modified Rankin Scale (mRS) at 3 months. Associations between WMH volumes and ENI were analyzed using binary logistic regression and visualized with restricted cubic splines. Proportional-odds ordinal logistic regression was performed to assess the relationship between WMH volumes and the ordinal shift in 3-month mRS. Results: A total of 170 patients (mean age, 66.5 ± 12.0 years; 57.1% men) were included. Median interquartile range volumes of total, periventricular, and deep WMH were 9.02 3.64–19.35, 5.88 2.14–12.96, and 2.21 0.95–5.24 mL, respectively. ENI was achieved in 88 (51.8%) patients following iHT, and its likelihood decreased significantly with greater WMH volumes (adjusted OR per 2-fold increase in WMH volume: total, 0.59 95% CI, 0.45–0.77; periventricular, 0.60 0.46–0.77; deep, 0.69 0.55–0.87). Higher periventricular WMH volume also showed a non-significant trend toward lower odds of achieving a favorable 3-month mRS (adjusted proportional OR per 2-fold increase, 0.84 0.68-1.04; p=0.093). Conclusions: Greater WMH burden was associated with poorer response to iHT in patients with SVO stroke who developed END. Alternative therapeutic strategies for END may be warranted in patients exhibiting advanced WMH.