Abstract Number: Esoc2026a810 Impact of Low Systolic Blood Pressure on Periventricular White Matter Hyperintensities in Elderly Patients With Controlled Hypertension

Abstract Background and aims Both high and low blood pressure can contribute to cerebral white matter hyperintensities (WMH). However, the effect of hypotension in patients with treated hypertension is unclear. This study examined the association between low blood pressure and WMH volume and location in elderly patients with controlled hypertension compared to those without hypertension. Methods We prospectively enrolled 312 cognitively normal elderly patients from March 2023 to March 2025 at Al-Azhar University Hospitals and Cairo Al-Fatimia Hospitals. Blood pressure was measured three times in a sitting position using a mercury sphygmomanometer. Low systolic blood pressure (SBP) was defined as ≤110 mm Hg and low diastolic blood pressure (DBP) as ≤60 mm Hg. Periventricular and deep WMH volumes were segmented and quantified from 1.5 Tesla FLAIR MRI scans. Results Low SBP was independently associated with greater periventricular WMH volume (P=0.048), with a significant interaction between low SBP and hypertension history (P=0.006). Among 140 patients with controlled hypertension, 42 (30%) had low SBP, which was linked to increased periventricular WMH (F1,138=7.2, P=0.009). In contrast, among 172 patients without hypertension, 25 (14.5%) had low SBP, with no significant association with WMH (P=0.39). Low DBP was observed in 38 patients (12.2%) and showed no significant relationship with WMH volumes in either group. Conclusions Low systolic blood pressure is associated with increased periventricular WMH volume in elderly patients with controlled hypertension but not in those without hypertension. Diastolic hypotension does not appear to influence WMH volumes. Conflict of interest Nothing to disclose