Background and purposeThe association between blood pressure variability (BPV) and stroke recurrence among patients who had ischaemic stroke (IS) remains unclear. This study aimed to investigate the association between BPV and stroke recurrence in patients who had IS of large artery atherosclerosis (LAA) subtype and small artery occlusion (SAO) subtype.MethodsData from the BOSS (Blood Pressure and Clinical Outcome in Transient Ischemic Attack or Ischemic Stroke) study were examined. IS subtypes were diagnosed according to the Trial of Org 10172 in Acute Stroke Treatment criteria. BPV was performed by 24-hour ambulatory blood pressure monitoring and defined through SD of blood pressure. The primary outcome was stroke recurrence within 90 days after discharge. Multivariable Cox regression model was used to assess the association between BPV and stroke recurrence in patients who had IS of LAA subtype and SAO subtype.ResultsA total of 1390 patients who had IS from the BOSS study were included in the present study. Multivariable analysis suggests that 24-hour systolic BPV (SBPV) and night-time diastolic BPV (DBPV) were significantly associated with stroke recurrence among all patients who had IS (HR, 2.50, 95% CI 1.07 to 5.84; HR, 1.85, 95% CI 1.07 to 3.21, respectively). Night-time SBPV and night-time DBPV were significantly associated with stroke recurrence in patients with SAO subtype (HR, 2.77, 95% CI 1.07 to 7.15; HR, 3.60, 95% CI 1.39 to 9.29, respectively). However, in the adjusted model, only night-time DBPV remained significant in patients with SAO subtype (HR, 3.87, 95% CI 1.40 to 10.71). Similar results were not found in patients who had IS of LAA subtype.ConclusionsHigh night-time DBPV was associated with increased risk of stroke recurrence among patients who had IS of SAO subtype. The results of this study have implications for the secondary prevention management and future research of patients who had IS of SAO subtype. The association between BPV and stroke recurrence in patients who had IS of LAA subtype and SAO subtype should be investigated in larger, population-based studies.