Prabhakaran, Shyam

BACKGROUND: Intracranial atherosclerosis (ICAS) is associated with an increased risk of early recurrent ischemic stroke. We evaluated whether biomarkers of impaired distal perfusion—specifically, anterior circulation borderzone infarct, and hypoperfusion mismatch volume—were associated with recurrent ischemic stroke within 90 days. METHODS: The BIORISK ICAS (Biomarkers and Recurrence Risk in Symptomatic Intracranial Atherosclerosis) is a multicenter retrospective international study (35 sites) that included hospitalized patients with symptomatic ICAS (50%–99% luminal stenosis of the intracranial vertebral, basilar, distal internal carotid, or proximal middle cerebral artery) from January 2019 to June 2024. The primary outcome was recurrent ischemic stroke in the territory of the symptomatic artery within 90 days. In the primary analysis, the exposure was an acute anterior circulation borderzone infarct. In secondary analysis of the subset with presentation within 72 hours of last known normal and perfusion imaging completed, the exposure of interest was prespecified as hypoperfusion mismatch volume at T max (time to maximum) threshold of 6 seconds, dichotomized at the Youden index. We performed multivariable Cox regression to test associations between exposure variables and the outcome, adjusting for clinically relevant variables and those associated with the outcome ( P <0.1). RESULTS: Of 2050 patients with symptomatic ICAS, 1737 (84.7%) presented within 72 hours of symptom onset, among whom 509 (29.3%) underwent perfusion imaging. The primary analysis included 1891 patients; 174 (9.2%) patients had recurrent ischemic stroke in the symptomatic arterial territory. In adjusted Cox regression models, there was an association between anterior circulation borderzone infarct and recurrent ischemic stroke at 90 days (adjusted hazard ratio, 1.40 [95% CI, 1.02–1.93]). In the perfusion imaging analysis, hypoperfusion mismatch of ≥10 mL was associated with recurrent ischemic stroke (adjusted hazard ratio, 1.83 [95% CI, 1.03–3.28]). CONCLUSIONS: Biomarkers of impaired distal perfusion, anterior circulation borderzone infarct, and hypoperfusion mismatch were associated with increased risk of recurrent ischemic stroke. These findings support the use of perfusion imaging in ICAS as well as future trials investigating early reperfusion in high-risk patients with ICAS.

Background: Treatment of uncontrolled arterial hypertension reduces the risk of cerebral small vessel disease (CSVD) progression, although it is unclear whether this reduction occurs due to blood pressure control or class-specific pleiotropic effects, such as improved beat-to-beat arterial pressure variability with calcium channel blockers. The goal of this study was to investigate the influence of antihypertensive medication class, particularly with calcium channel blocker, on accumulation of white matter hyperintensities (WMH), a radiographic marker of CSVD, within a cohort with well-controlled hypertension. Methods: We completed an observational cohort analysis of the SPRINT-MIND trial (Systolic Blood Pressure Trial Memory and Cognition in Decreased Hypertension), a large randomized controlled trial of participants who completed a baseline and 4-year follow-up brain magnetic resonance image with volumetric WMH data. Antihypertensive medication data were recorded at follow-up visits between the magnetic resonance images. A percentage of follow-up time participants were prescribed each of the 11 classes of antihypertensive was then derived. Progression of CSVD was calculated as the difference in WMH volume between 2 scans and, to address skew, dichotomized into a top tertile of the distribution compared with the remaining. Results: Among 448 individuals, vascular risk profiles were similar across WMH progression subgroups except age (70.1±7.9 versus 65.7±7.3 years; P <0.001) and systolic blood pressure (128.3±11.0 versus 126.2±9.4 mm Hg; P =0.039). Seventy-two (48.3%) of the top tertile cohort and 177 (59.2%) of the remaining cohort were in the intensive blood pressure arm. Those within the top tertile of progression had a mean WMH progression of 4.7±4.3 mL compared with 0.13±1.0 mL ( P <0.001). Use of angiotensin-converting enzyme inhibitors (odds ratio, 0.36 [95% CI, 0.16–0.79]; P =0.011) and dihydropyridine calcium channel blockers (odds ratio, 0.39 [95% CI, 0.19–0.80]; P =0.011) was associated with less WMH progression, although dihydropyridine calcium channel blockers lost significance when WMH was treated as a continuous variable. Conclusions: Among participants of SPRINT-MIND trial, angiotensin-converting enzyme inhibitor was most consistently associated with less WMH progression independent of blood pressure control and age.