BACKGROUND: Intracranial atherosclerotic stenosis (ICAS) is a major cause of stroke and cognitive impairment. We evaluated whether nighttime systolic blood pressure (SBP) provides additional information beyond daytime SBP regarding cognition, ICAS burden, and plasma biomarkers in patients with ICAS. METHODS: In this multicenter cross-sectional study, patients with ICAS underwent 24-hour ambulatory BP monitoring, brain magnetic resonance imaging, plasma biomarker assays, and neuropsychological testing. Multivariable models including both daytime and nighttime SBP assessed associations with ICAS burden, cerebral small vessel disease burden, plasma biomarkers, and cognition. Incremental analyses evaluated additional information from nighttime SBP beyond daytime SBP. Structural equation modeling examined patterns of associations among SBP, ICAS burden, NfL (neurofilament light chain), and cognition. RESULTS: =0.007) independent of daytime SBP. Among biomarkers, only NfL was consistently associated with nighttime SBP. Incremental analyses supported additional information from nighttime SBP beyond daytime SBP for cognition, ICAS burden, and NfL. In structural equation modeling, the association between nighttime SBP and cognition was more closely aligned with NfL than with ICAS burden. CONCLUSIONS: In ICAS, nighttime SBP provides additional information beyond daytime SBP for cognition, vascular burden, and neuroaxonal injury. Nighttime SBP and plasma NfL may represent complementary indicators of vascular stress and cognitive vulnerability.
Zhou et al. (Wed,) studied this question.