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Background and Purpose: Blood pressure variability (BPV) from beat to beat is associated with an increased risk of cardiovascular events and enables rapid assessment of BPV, but the underlying causes of elevated BPV are unclear. Methods: In consecutive patients within 4 to 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), continuous noninvasive blood pressure was measured beat to beat over 5 minutes (Finometer). Arterial stiffness was measured by carotid-femoral pulse wave velocity (Sphygmocor). After automated and manual data cleaning, associations between BPV (residual coefficient of variation), demographic factors, and arterial stiffness were determined for both systolic and diastolic blood pressure, by ANOVA and linear models. Relationships between demographic factors and arterial stiffness were determined by interaction terms and mediation. Results: Among 1013 patients, 54 (5.3%) were in AF, and 51 (5%) had low-quality recordings. In a general linear model including the remaining 908 participants, systolic BPV (SBPV) was most strongly associated with age ( P =0.00003), body mass index (BMI; P =0.003), and arterial stiffness ( P =0.008), with weaker independent associations with current smoking ( P =0.01) and a low diastolic blood pressure ( P =0.046). However, while there was a linear increase in SBPV with BMI in men, in women, SBPV was lowest for a BMI in the normal range but was greater below 20 or above 30 (ANOVA, P =0.012; BMI-sex interaction, P =0.03). Although BMI and pulse wave velocity were partially independent, increased pulse wave velocity mediated ≈32% of the relationship between increased BMI and SBPV ( P Conclusions: Vascular aging, manifest as arterial stiffness, was a strong determinant of increased SBPV and partially mediated the effect of increased BMI. However, although high BMI was independently associated with SBPV in both sexes, a low BMI was associated with increased SBPV only in women. SBPV may partially mediate the relationship between BMI and cardiovascular events, while obesity may provide a modifiable target to reduce SBPV and cardiovascular events.

Background: Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. Methods: In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), arterial stiffness (pulse wave velocity [PWV]) and aortic systolic, aortic diastolic, and aortic pulse pressures (aoPP) were measured by applanation tonometry (Sphygmocor), while middle cerebral artery (MCA) peak (MCA-PSV) and trough (MCA-EDV) flow velocity and Gosling pulsatility index (PI; MCA-PI) were measured by transcranial ultrasound (transcranial Doppler, DWL Doppler Box). Repeat assessments were performed at the 5-year follow-up visit after intensive medical treatment and agreement determined by intraclass correlation coefficients. Rates of progression and their determinants, stratified by age and sex, were determined by mixed-effects linear models, adjusted for age, sex, and cardiovascular risk factors. Results: In 188 surviving, eligible patients with repeat assessments after a median of 5.8 years. PWV, aoPP, and MCA-PI were highly reproducible (intraclass correlation coefficients, 0.71, 0.59, and 0.65, respectively), with progression of PWV (2.4%; P P P =0.22). However, PWV increased at a faster rate with increasing age (0.009 m/s per y/y; P P P =0.009). Higher aortic systolic blood pressure and diastolic blood pressure predicted a greater rate of progression of PWV and aoPP, but not MCA-PI, although current MCA-PI was particularly strongly associated with concurrent aoPP ( P Conclusions: Arterial pulsatility and aortic stiffness progressed significantly after 55 years of age despite the best medical treatment. Progression of stiffness and aoPP was determined by high blood pressure, but MCA-PI predominantly reflected current aoPP. Treatments targetting cerebral pulsatility may need to principally target aortic stiffness and pulse pressure to have the potential to prevent cerebral small vessel disease.

Supplemental Digital Content is available in the text., Background and Purpose— Breath holding (BH) and hyperventilation are used to assess abnormal cerebrovascular reactivity, often in relation to severity of small vessel disease and risk of stroke with carotid stenosis, but responses may be confounded by blood pressure (BP) changes. We compared effects of BP and end-tidal carbon dioxide (etCO2) on middle cerebral artery mean flow velocity (MFV) in consecutive transient ischemic attack and minor stroke patients. Methods— In the population-based, prospective OXVASC (Oxford Vascular Study) phenotyped cohort, change in MFV on transcranial Doppler ultrasound (ΔMFV, DWL-DopplerBox), beat-to-beat BP (Finometer), and etCO2 was measured during 30 seconds of BH or hyperventilation. Two blinded reviewers independently assessed recording quality. Dependence of ΔMFV on ΔBP and ΔetCO2 was determined by general linear models, stratified by quartiles. Results— Four hundred eighty-eight of 602 (81%) patients with adequate bone windows had high-quality recordings, more often in younger participants (64.6 versus 68.7 years; P

Supplemental Digital Content is available in the text., Background and Purpose— Visit-to-visit and day-to-day blood pressure (BP) variability (BPV) predict an increased risk of cardiovascular events but only reflect 1 form of BPV. Beat-to-beat BPV can be rapidly assessed and might also be predictive. Methods— In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (Oxford Vascular Study), BPV (coefficient of variation) was measured beat-to-beat for 5 minutes (Finometer), day-to-day for 1 week on home monitoring (3 readings, 3× daily), and on awake ambulatory BP monitoring. BPV after 1-month standard treatment was related (Cox proportional hazards) to recurrent stroke and cardiovascular events for 2 to 5 years, adjusted for mean systolic BP. Results— Among 520 patients, 26 had inadequate beat-to-beat recordings, and 22 patients were in atrial fibrillation. Four hundred five patients had all forms of monitoring. Beat-to-beat BPV predicted recurrent stroke and cardiovascular events independently of mean systolic BP (hazard ratio per group SD, stroke: 1.47 [1.12–1.91]; P=0.005; cardiovascular events: 1.41 [1.08–1.83]; P=0.01), including after adjustment for age and sex (stroke: 1.47 [1.12–1.92]; P=0.005) and all risk factors (1.40 [1.00–1.94]; P=0.047). Day-to-day BPV was less strongly associated with stroke (adjusted hazard ratio, 1.29 [0.97–1.71]; P=0.08) but similarly with cardiovascular events (1.41 [1.09–1.83]; P=0.009). BPV on awake ambulatory BP monitoring was nonpredictive (stroke: 0.89 [0.59–1.35]; P=0.59; cardiovascular events: 1.08 [0.77–1.52]; P=0.65). Despite a weak correlation (r=0.119; P=0.02), beat-to-beat BPV was associated with risk of recurrent stroke independently of day-to-day BPV (1.41 [1.05–1.90]; P=0.02). Conclusions— Beat-to-beat BPV predicted recurrent stroke and cardiovascular events, independently of mean systolic BP and risk factors but short-term BPV on ambulatory BP monitoring did not. Beat-to-beat BPV may be a useful additional marker of cardiovascular risk.

Background and Purpose— Among screening tools for cognitive impairment in large cohorts, the Montreal Cognitive Assessment (MoCA) seems to be more sensitive to early cognitive impairment than the Mini-Mental State Examination (MMSE), particularly after transient ischemic attack or minor stroke. We reasoned that if MoCA-detected early cognitive impairment is pathologically significant, then it should be specifically associated with the presence of white matter hyperintensities (WMHs) and reduced fractional anisotropy (FA) on magnetic resonance imaging. Methods— Consecutive eligible patients with transient ischemic attack or minor stroke (Oxford Vascular Study) underwent magnetic resonance imaging and cognitive assessment. We correlated MoCA and MMSE scores with WMH and FA, then specifically studied patients with low MoCA and normal MMSE. Results— Among 400 patients, MoCA and MMSE scores were significantly correlated (all P r MoCA =−0.336; r MMSE =−0.297) and FA ( r MoCA =0.409; r MMSE =0.369) and—on voxel-wise analyses—with WMH in frontal white matter and reduced FA in almost all white matter tracts. However, only the MoCA was independently correlated with WMH volumes ( r =−0.183; P r =0.218; P t =3.1; P =0.002), lower average FA ( t =−4.0; P Conclusions— In patients with transient ischemic attack or minor stroke, early cognitive impairment detected with the MoCA but not with the MMSE was independently associated with white matter damage on magnetic resonance imaging, particularly reduced FA.

To the Editor: With regard to the article from Zigari et al,1 we would like to add some comments to the authors’ reply2 to our letter.3 The authors are very welcome to …