Characteristics of Blood Pressure Profiles as Predictors of Long-Term Outcome After Acute Ischemic Stroke

Prognostic value of beat-to-beat blood pressure variability parameters in patients after mechanical thrombectomy

The relationship of beat-to-beat blood pressure variability (BPV) with prognosis after mechanical thrombectomy (MT) is unclear. Consecutive patients with acute ischemic stroke with large vessel occlusion treated with and without MT matched 1:1 by age, sex, and National Institutes of Health Stroke Scale were included. Beat-to-beat BPV was calculated for both systolic (SBP) and diastolic blood pressure (DBP) as standard deviation, coefficient of variation, successive variation (SV), and average real variability (ARV) at 24-72 h after MT. Additionally, hour-to-hour (first 24 h after MT) and day-by-day BPV (first 7 days after MT) were also measured. The outcome was modified Rankin Scale (mRS) at 3 months. Of 168 patients, 84 patients received MT and 84 did not. MT closely correlated with lower beat-to-beat BPV parameters. Beat-to-beat SBP-SV and SBP-ARV were significantly higher in patients with unfavorable outcome than in those with favorable outcome (median 3.40 vs 2.71; P = 0.016; median 2.81 vs 2.20, P = 0.003). After adjusting for confounders, higher beat-to-beat SBP-SV and SBP-ARV were independently associated with unfavorable outcome in patients with MT (all P < 0.05). However, no association was found between hour-to-hour and day-by-day BPV and outcome at 3 months (P > 0.05). The patients with MT had lower beat-to-beat BPV values in the acute phase, which indicated that MT has a positive effect on beat-to-beat BPV. Furthermore, beat-to-beat BPV, rather than hour-to-hour or day-by-day BPV, is an independent risk factor for unfavorable outcome in patients after MT.

Association of Early Blood Pressure Levels and Outcomes in Ischemic Stroke Treated With Intravenous Thrombolysis: A Prospective Cohort Study

BACKGROUND AND PURPOSE

Current guidelines for acute ischemic stroke (AIS) treatment recommend a lenient upper blood pressure (BP) threshold of 185/110 mmHg. However, stricter BP control has been reported to improve prognosis. This study aims to identify the optimal BP range following thrombolysis.

METHODS

This observational study included 340 AIS patients treated with rt-PA thrombolysis at the First Affiliated Hospital of Wenzhou Medical University from December 2017 to December 2021. BP levels 24 h after thrombolysis were analyzed to determine their association with clinical outcomes. BP parameters included mean BP, variability (standard deviation (SD)), and decreased magnitudes. The primary outcome was the 90-day modified Rankin Scale (mRS) scores.

RESULTS

Higher mean systolic BP (SBP) was associated with poorer outcomes, with adjusted odds ratios (aORs) of 1.25 (95% CI, 1.03-1.51), 1.23 (1.01-1.49), and 1.25 (1.02-1.52) per 10 mmHg increase within 0-2 h, 2-6 h, and 6-24 h post-thrombolysis, respectively, but not for BP variability and decrease magnitudes. Significant improvements in outcomes were observed when the mean SBP was maintained within the range of 120-140 mmHg during both the 0-2 and 2-6 h periods, with aORs of 0.12 (95% CI, 0.02-0.75) and 0.19 (0.04-0.82), respectively. Larger decreases in SBP within 6 h post-thrombolysis were associated with a lower risk of intracerebral hemorrhage. These findings were consistent across subgroups and sensitivity analyses.

CONCLUSIONS

Achieving sustained low SBP levels (120-140 mmHg within the first 6 h) over 24 h is linked to better outcomes in thrombolyzed AIS patients.

Prevalence, Trajectory, and Factors Associated With Patient-Reported Nonmotor Outcomes After Stroke: A Systematic Review and Meta-Analysis

Importance

The evidence on nonmotor outcomes after acute ischemic stroke and intracerebral hemorrhage (ICH) is limited and domain-specific. The prevalence, natural history, and factors associated with nonmotor outcomes across multiple domains are unclear.

Objective

To synthesize the published data and to identify the prevalence, natural history, and factors associated with multidomain nonmotor outcome burden in patients with stroke.

Data Sources

A search of PubMed, MEDLINE, EMBASE, and PsycINFO databases between January 1999 to June 2023 was supplemented by search of bibliographies of the key articles.

Study Selection

The analysis included prospective cohort studies that reported nonmotor outcomes across 10 domains: anxiety, depression, fatigue, sleep disturbance, social participation, pain, bladder dysfunction, bowel dysfunction (constipation and fecal incontinence), and sexual dysfunction assessed by patient-reported scales.

Data Extraction and Synthesis

Two reviewers independently assessed studies, extracting baseline data, nonmotor prevalence, and follow-up information. Pooled prevalence of nonmotor outcomes was estimated using random-effects models. Meta-regression models were used to analyze natural history and factors associated with nonmotor outcomes. Subgroup analysis was used to assess prevalence by symptom description within each nonmotor domain. Publication bias and study quality were assessed using funnel plots and the Newcastle-Ottawa scale.

Results

A total of 279 prospective cohort studies met the inclusion criteria (117 440 participants with stroke; median [IQR] age, 65 [59-70] years; 209 of 279 studies with more male than female participants) with a nonmotor outcome follow-up period ranging from 30 days to 10 years after stroke. The most prevalent adverse nonmotor outcomes by pooled prevalence were sleep disturbance (59.9%; 95% CI, 53.9%-63.9%), sexual dysfunction (59.8%; 95% CI, 50.0%-69.5%), constipation (58.2%; 95% CI, 53.9%-62.6%), reduced social participation (56.5%; 95% CI, 52.1%-60.8%), bladder dysfunction (45.9%; 95% CI, 38.0%-53.8%), and fatigue (45.2%; 95% CI, 40.7%-49.5%). Meta-regression analysis showed no significant improvement over time for most nonmotor outcomes, except pain (coefficient = -11.0%; P = .05) and sexual dysfunction (coefficient = -24.1%; P < .001). The heterogeneity ranged between 52% and 98% across all studies. The common factors associated with adverse nonmotor outcomes were female sex, studies with mixed stroke cohort (ischemic stroke or ICH), and older age.

Conclusions and Relevance

Patient-reported nonmotor outcomes were common after stroke. Sexual dysfunction, sleep disturbance, constipation, reduced social participation, bladder dysfunction, and fatigue were most prevalent. These adverse outcomes often persisted over time, especially in women, older adults, and those in studies with mixed stroke cohorts.

Intracerebral arterial blood pressure in the vasculature distal to large vessel occlusions in patients with ischemic stroke: correlation with clinical and imaging parameters

INTRODUCTION

Mechanical thrombectomy is a highly effective treatment for acute ischemic stroke (AIS) caused by large vessel occlusions (LVO). However, our understanding of the pathophysiology of AIS is still limited, particularly regarding the ischemic microenvironment distal to the occlusion.

AIM

To investigate the relationship between the intracerebral blood pressure (BP) distal to an LVO and clinical and imaging parameters.

METHODS

In this single-center prospective study, intracerebral BPs proximal and distal to the occluding clot were measured during thrombectomy in patients with AIS of the anterior circulation caused by LVO. BPs were correlated with imaging parameters and clinical data using Spearman's rank correlation and linear regression.

RESULTS

25 patients were included. A significant correlation was found between the mean arterial pressure (MAP) distal to the occlusion and the baseline Alberta Stroke Program Early CT Score (Spearman r=0.503, P=0.014) and baseline National Institutes of Health Stroke Scale score (r=-0.439, P=0.036). No significant correlation was observed between the MAP distal to the occlusion and collateral scores (eg, MAP vs American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology score (r=0.307, P=0.165) or modified Rankin Scale (mRS) score (pre-mRS vs 90-day mRS; r=0.013, P=0.952)). Systemic MAPs did not correlate with the MAP distal to the clot (eg, R2=0.029, P=0.593).

CONCLUSION

The intracerebral BP measured in the ischemic vasculature distal to the LVO correlates with the extent of the ischemic core and the clinical severity at baseline, but not with collateral scores, systemic BPs, or functional outcome. These results shed light on the pathophysiology of BP mechanisms in AIS and can be the basis for further research in this field.

TEMR: Trans-ethnic mendelian randomization method using large-scale GWAS summary datasets

Available large-scale genome-wide association study (GWAS) summary datasets predominantly stem from European populations, while sample sizes for other ethnicities, notably Central/South Asian, East Asian, African, Hispanic, etc., remain comparatively limited, resulting in low precision of causal effect estimations within these ethnicities when using Mendelian randomization (MR). In this paper, we propose a trans-ethnic MR method, TEMR, to improve the statistical power and estimation precision of MR in a target population that is underrepresented, using trans-ethnic large-scale GWAS summary datasets. TEMR incorporates trans-ethnic genetic correlation coefficients through a conditional likelihood-based inference framework, producing calibrated p values with substantially improved MR power. In the simulation study, compared with other existing MR methods, TEMR exhibited superior precision and statistical power in causal effect estimation within the target populations. Finally, we applied TEMR to infer causal relationships between concentrations of 16 blood biomarkers and the risk of developing five diseases (hypertension, ischemic stroke, type 2 diabetes, schizophrenia, and major depression disorder) in East Asian, African, and Hispanic/Latino populations, leveraging biobank-scale GWAS summary data obtained from individuals of European descent. We found that the causal biomarkers were mostly validated by previous MR methods, and we also discovered 17 causal relationships that were not identified using previously published MR methods.

Association between 24-hour blood pressure parameters and 90-day functional outcome in acute ischemic stroke patients with early anticoagulation

This study aimed to examine the relationship between blood pressure (BP) and blood pressure variability (BPV) during the first 24 hours from admission with 90-day functional outcomes in acute ischemic stroke (AIS) patients whose onset within 24 hours and receiving early argatroban treatment. The study recruited 214 AIS patients. BP was monitored using a cuff at 1-hour fixed intervals, and BP/BPV parameters [standard deviation (SD), coefficient of variation (CV), successive variation (SV), and average real variability (ARV)] were collected. Age, the National Institutes of Health Stroke Scale (NIHSS) score at admission, previous history of diabetes mellitus (DM), and infarction site (located in anterior circulation) were identified as independent factors affecting 90-day outcomes in multiple logistic regression. After adjusting for confounding variables, association between BP/BPV and 90-day modified Rankin Scale (mRS) was assessed using logistic regression models. In model 1 (adjusted for age and NIHSS score at admission), mean-systolic blood pressure (SBP) showed association with 90-day outcomes [1.068 (1.008, 1.131), P = .025]. In model 2 (adjusted for age, NIHSS score at admission, previous history of DM), mean-SBP [1.061 (1.001, 1.123), P = .045] and max-SBP [0.951 (0.906, 0.998), P = .040] showed relatively weak association with outcomes. In model 3 [adjusted for age, NIHSS score at admission, previous history of DM, infarct site (located in anterior circulation)], all BP values were not related with outcomes, meanwhile, none of the BPV parameters calculated from SBP, diastolic blood pressure and mean arterial pressure showed association with 90-day outcomes. Future prospective studies are required to assess the relationship between early BP/BPV parameters with 90-day outcomes and further clarify the reference values for BP parameters. This is important for effective BP/BPV management and improved patient prognosis.

Association between antihypertensive treatment, blood pressure variability, and stroke severity and outcomes in acute ischemic stroke

OBJECTIVES

The management of blood pressure (BP) and the role of antihypertensive medications (AHT) in acute ischemic stroke (AIS) remain uncertain. This study aimed to investigate the impact of pre- and intra-stroke AHT use on systolic (SBP), diastolic (DBP), and blood pressure variability (BPV).

MATERIALS AND METHODS

A post-hoc analysis was conducted on 228 AIS patients from the PREVISE study. All patients underwent 24-hour ambulatory blood pressure monitoring within 48 h of symptom onset. Clinical and laboratory data, as well as AHT details, were recorded. Mean BP parameters and BPV for SBP and DBP were computed. The study endpoint was 3-month mortality.

RESULTS

The majority of stroke patients (84.2%) were already taking AHTs. Beta blockers and ACE inhibitors use before and after stroke were linked to higher DBP variability. Prior angiotensin receptor blockers (ARBs) and vasodilators use correlated with increased SBP variability and lower daytime SBP/DBP levels, respectively. The continuation, discontinuation, or change of AHTs after stroke onset did not significantly affect outcomes. Patients under AHTs during AIS exhibited reduced mortality, with those previously using calcium channel blockers experiencing less severe strokes, and those previously using ARBs showing better outcomes at three months.

CONCLUSIONS

These findings advocate for personalized BP management in AIS, based on a patient's antihypertensive history. These insights could enhance treatment efficacy, guide research, and improve care for acute ischemic stroke patients.

Predicting prognosis in patients with stroke treated with intravenous alteplase through blood pressure changes: A machine learning-based approach

The use of machine learning (ML) in predicting disease prognosis has increased, and researchers have adopted different methods for variable selection to optimize early screening for AIS to determine its prognosis as soon as possible. We aimed to improve the understanding of the predictors of poor functional outcome at three months after discharge in AIS patients treated with intravenous thrombolysis and to construct a highly effective prognostic model to improve prediction accuracy. And four ML methods (random forest, support vector machine, naive Bayesian, and logistic regression) were used to screen and recombine the features for construction of an ML prognostic model. A total of 352 patients that had experienced AIS and had been treated with intravenous thrombolysis were recruited. The variables included in the model were NIHSS on admission, age, white blood cell count, percentage of neutrophils and triglyceride after thrombolysis, tirofiban, early neurological deterioration, early neurological improvement, and BP at each time point or period. The model's area under the curve for predicting 30-day modified Rankin scale was 0.790 with random forest, 0.542 with support vector machine, 0.411 with naive Bayesian, and 0.661 with logistic regression. The random forest model was shown to accurately evaluate the prognosis of AIS patients treated with intravenous thrombolysis, and therefore they may be helpful for accurate and personalized secondary prevention. The model offers improved prediction accuracy that may reduce rates of misdiagnosis and missed diagnosis in patients with AIS.

Prognostic significance of 24-h blood pressure and variability indices in the outcome of acute ischaemic stroke

BACKGROUND

The association between blood pressure (BP) levels and BP variability (BPV) following acute ischaemic stroke (AIS) and outcome remains controversial.

AIMS

To investigate the predictive value of systolic BP (SBP) and diastolic BP (DBP) and BPV measured using 24-h ambulatory blood pressure monitoring (ABPM) methods during AIS regarding outcome.

METHODS

A total of 228 AIS patients (175 without prior disability) underwent ABPM every 20 min within 48 h from onset using an automated oscillometric device (TM 2430, A&D Company Ltd) during day time (7:00-22:59) and night time (23:00-6:59). Risk factors, stroke subtypes, clinical and laboratory findings were recorded. Mean BP parameters and several BPV indices were calculated. End-points were death and unfavourable functional outcome (disability/death) at 3 months.

RESULTS

A total of 61 (26.7%) patients eventually died. Multivariate logistic regression analysis revealed that only mean night-time DBP (hazard ratio (HR): 1.04; 95% confidence interval (CI): 1.00-1.07) was an independent prognostic factor of death. Of the 175 patients without prior disability, 79 (45.1%) finally met the end-point of unfavourable functional outcome. Mean 24-h SBP (HR: 1.03; 95% CI: 1.00-1.05), day-time SBP (HR: 1.02; 95% CI: 1.00-1.05) and night-time SBP (HR: 1.03; 95% CI: 1.01-1.05), SBP nocturnal decline (HR: 0.93; 95% CI: 0.88-0.99), mean 24-h DBP (HR: 1.08; 95% CI: 1.03-1.13), day-time DBP (HR: 1.07; 95% CI: 1.03-1.12) and night-time DBP (HR: 1.06; 95% CI: 1.02-1.10) were independent prognostic factors of an unfavourable functional outcome.

CONCLUSIONS

In contrast with BPV indices, ABPM-derived BP levels and lower or absence of BP nocturnal decline in the acute phase are prognostic factors of outcome in AIS patients.

Systolic blood pressure in acute ischemic stroke and impact on clinical outcomes

CONTEXT

Stroke is one of the largest healthcare burdens in the United States and globally. It continues to be one of the leading causes of morbidity and mortality. Patients with acute ischemic stroke (AIS) often present with elevated blood pressure (BP).

OBJECTIVES

The objective of our study was to evaluate the association of systolic blood pressure (SBP) in the emergency department (ED) with stroke severity in patients with AIS.

METHODS

This observational study was conducted at an ED with an annual census of 80,000 visits, approximately half (400) of which are for AIS. The cohort consisted of adult patients who presented to the ED within 24 h of stroke symptom onset. BP was measured at triage by a nurse blinded to the study. Stroke severity was measured utilizing the National Institutes of Health Stroke Scale (NIHSS). Statistical analyses were performed utilizing JMP 14.0. This study was approved by our medical school's institutional review board.

RESULTS

Patients with higher SBP had significantly lower NIHSS scores (p=0.0038). This association was significant even after adjusting for age and gender. By contrast, diastolic blood pressure (DBP) did not appear to impact stroke severity. There was no difference in the DBP values between men and women. Higher SBP was also significantly associated with being discharged home as well as being less likely to die in the hospital or discharged to hospice. The DBP did not demonstrate this association. Neither the SDP nor the DBP were significantly associated with the hospital length of stay (LOS). In multivariate models that included age, gender, basal metabolic index (BMI), comorbidities, and ED presentation, elevated SBP was associated with better prognosis.

CONCLUSIONS

In this cohort of patients presenting with stroke-like symptoms to the ED, higher SBP was associated with lower stroke severity and higher rates of being discharged to home rather than hospice or death.

Blood pressure management in ischemic stroke patients undergoing mechanical thrombectomy

The relationship between presenting blood pressure in acute ischemic stroke patients and outcome is complex. Several studies have demonstrated a U-shaped curve with worse outcomes when blood pressure is high or low. The American Heart Association/American Stroke Association guidelines recommend values of blood pressure < 185/110 mmHg in patients treated with intravenous t-PA and "permissive hypertension" up to 220/120 mmHg in those not treated with intravenous t-PA. The optimal blood pressure target is less clear in patients undergoing mechanical thrombectomy. Before thrombectomy, the guidelines recommend a blood pressure < 185/110 mmHg though patients with even lower systolic blood pressures may have better outcomes. During and after thrombectomy, the guidelines recommend a blood pressure < 180/105 mmHg. However, several studies have suggested that during thrombectomy the primary goal should be to prevent significant low blood pressure (e.g., target systolic blood pressure > 140 mmHg or MAP > 70 mmHg). After thrombectomy, the primary goal should be to prevent high blood pressure (e.g., target systolic blood pressure < 160 mmHg or MAP < 90 mmHg). To make more specific recommendations, large, randomized-control studies are needed that address factors such as the baseline blood pressure, timing and degree of revascularization, status of collaterals, and estimated risk of reperfusion injury.

Association of disrupted sleep with 24-hour blood pressure variability in caregivers

BACKGROUND

A growing body of research highlights the negative impact of caregiving on cardiovascular disease (CVD) risk.

OBJECTIVES

This study aimed to examine associations of psychological symptoms and sleep quality with 24-hour blood pressure variability (BPV), which is an independent predictor of CVD, among family caregivers of community-dwelling individuals with chronic illness.

METHODS

For this cross-sectional study, we assessed caregiving burden and depressive symptoms using questionnaires and 7-day sleep quality (i.e., number of awakenings, wake after sleep onset, sleep efficiency) using an actigraph. The participants carried out a 24-hour ambulatory BP monitoring for systolic and diastolic BPV over 24 h and during awake/sleep times. We performed Pearson's correlations and multiple linear regression.

RESULTS

The analytic sample consisted of 30 caregivers (25 female; mean age 62 years). The number of awakenings during sleep was positively correlated with systolic BPV-awake (r = 0.426, p = 0.019) and diastolic BPV-awake (r = 0.422, p = 0.020). Sleep efficiency was negatively correlated with diastolic BPV-awake (r = -0.368, p = 0.045). Caregiving burden and depressive symptoms were not correlated with BPV. After controlling for age and mean arterial pressure, the number of awakenings was significantly associated with increased systolic BPV-24 h (β = 0.194, p = 0.018) and systolic BPV-awake (β = 0.280, p = 0.002), respectively.

CONCLUSIONS

Caregivers' disrupted sleep may play a role in increased CVD risk. While these findings should be confirmed in large clinical studies, improving sleep quality would need to be considered in CVD prevention for caregivers.

Increased blood pressure variability during general anaesthesia is associated with worse outcomes after mechanical thrombectomy: a prospective observational cohort study

OBJECTIVES

Optimal periprocedural blood pressure (BP) management during mechanical thrombectomy (MT) for acute ischaemic stroke is still controversial. The aim of this study was to investigate the association between intraprocedural BP variability (BPV) and outcomes in patients with large vessel occlusion (LVO) following MT with general anaesthesia.

DESIGN

A prospective observational cohort study.

SETTING

This study was conducted in a single tertiary hospital of Hangzhou in Zhejiang province.

PARTICIPANTS

A total of 141 patients with LVO treated with MT were finally included between January 2018 and September 2020.

MAIN OUTCOME MEASURES

Intraprocedural BP was recorded every 5 min throughout the procedure. BPV was measured as SD, coefficient of variation (CV), max-min (RANGE) and successive variation. Haemorrhagic transformation was assessed on 24-hour CT images according to European Cooperative Acute Stroke Study III trial. Poor functional outcome was defined as 90-day modified Rankin Scale score 3-6. Binary logistic regression analysis was used to investigate the association of BPV parameters with the incidence of parenchymal haemorrhage (PH) and poor functional outcome.

RESULTS

After controlling for age, female, history of smoking, hypertension and atrial fibrillation, baseline National Institutes of Health Stroke Scale, baseline systolic BP (SBP), baseline Alberta Stroke Program Early CT Score, bridging thrombolysis and times of retrieval attempts, the results demonstrated that intraprocedural SBP_RANGE (OR 1.029; 95% CI 1.003 to 1.055; p=0.027), SBP_SD (OR 1.135; 95% CI 1.023 to 1.259; p=0.017) and SBP_CV (OR 1.189; 95% CI 1.053 to 1.342; p=0.005) were independently associated with poor functional outcome. However, the independent association between intraprocedural BPV and PH at 24 hours has not been established in this study.

CONCLUSIONS

Increased intraprocedural BPV was more likely to have poor functional outcome in patients with LVO following MT with general anaesthesia. This finding indicates that special precautions should be taken to minimise BP fluctuation during procedure.

Remote diffusion-weighted imaging lesions and blood pressure variability in primary intracerebral hemorrhage

Objective

The aim of this study was to examine the association between remote diffusion-weighted imaging lesions (R-DWILs) and blood pressure variability (BPV) in patients with primary intracerebral hemorrhage (ICH).

Methods

We conducted a retrospective review of a consecutive cohort of 375 patients with primary ICH within 24 h onset. R-DWILs were defined as hyperintensity lesions in DWI remote from the hematoma. Blood pressure recordings were extracted up to 24 h post-admission. BPV was measured using SD, coefficient of variation (CV), and successive variation (SV).

Results

Remote DWI lesions were detected in 65 (17.3%) primary ICH patients. In multivariable logistic regression analysis, parameters of BPV were independently associated with R-DWILs, and the results remained consistent after being adjusted with mean SBP. SD, CV, and SV values in the highest quintile, showed 3- to 8-fold increased risk of R-DWILs, compared with the lowest quintile. ΔSBP demonstrated a significant difference in 2 different predictive models. Max SBP only dictated a significant difference in model 1. Mean SBP, admission SBP, and min SBP, failed to present an association with R-DWILs in model 1 or model 2.

Conclusion

Our results provided additional evidence that BPV is associated with the development of R-DWILs in primary ICH.

Acute Ischemic Stroke Comorbid with Type 2 Diabetes: Long-Term Prognosis Determinants in a 36-Month Prospective Study for Personalized Medicine

Ischemic stroke (IS) is often comorbid with type 2 diabetes mellitus (T2DM) wherein the determinants of long-term outcomes, beyond the acute stroke phase, are not adequately known. This study identified the determinants of long-term outcomes for diabetic IS patients through a prospective nested case-control study in 624 patients treated with conservative measures (38.60% females, mean age: 63.85 years). After 36-month follow-up, 117 (18.8%) patients with poor outcome were enrolled in the case group. The poor outcome was defined with a modified Rankin Scale (mRS) score ≥3. Meanwhile, 374 (59.9%) patients with good outcome, defined as (mRS score <3), were included in the control group. Patients who died (n = 32) or lost to follow-up (n = 101) were excluded in analysis. Poor prognostic outcome was positively associated with (1) the pulse rate at admission, (2) diastolic blood pressure (DBP), and (3) fasting blood glucose (FBG) during follow-up, whereas physical activity and lipid-lowering treatment during follow-up were negatively associated. Importantly, a forecasting model with these indicators distinguished the patients with good versus poor outcomes with 70.1% sensitivity and 73.5% specificity. Health care professionals and laboratory medicine scholars may want to monitor an increase in DBP and FBG during follow-up, as well as physical activity and lipid-lowering treatment, in relationship to the prognosis of IS with comorbid T2DM after conservative therapies. The proposed predictive model for personalized/precision medicine requires field testing in independent studies, and might help risk stratification with theranostic tests for patients with acute IS who also have a diagnosis of T2DM.

Integrative cerebral blood flow regulation in ischemic stroke

Optimizing cerebral perfusion is key to rescuing salvageable ischemic brain tissue. Despite being an important determinant of cerebral perfusion, there are no effective guidelines for blood pressure (BP) management in acute stroke. The control of cerebral blood flow (CBF) involves a myriad of complex pathways which are largely unaccounted for in stroke management. Due to its unique anatomy and physiology, the cerebrovascular circulation is often treated as a stand-alone system rather than an integral component of the cardiovascular system. In order to optimize the strategies for BP management in acute ischemic stroke, a critical reappraisal of the mechanisms involved in CBF control is needed. In this review, we highlight the important role of collateral circulation and re-examine the pathophysiology of CBF control, namely the determinants of cerebral perfusion pressure gradient and resistance, in the context of stroke. Finally, we summarize the state of our knowledge regarding cardiovascular and cerebrovascular interaction and explore some potential avenues for future research in ischemic stroke.

Integrative physiological assessment of cerebral hemodynamics and metabolism in acute ischemic stroke

Restoring perfusion to ischemic tissue is the primary goal of acute ischemic stroke care, yet only a small portion of patients receive reperfusion treatment. Since blood pressure (BP) is an important determinant of cerebral perfusion, effective BP management could facilitate reperfusion. But how BP should be managed in very early phase of ischemic stroke remains a contentious issue, due to the lack of clear evidence. Given the complex relationship between BP and cerebral blood flow (CBF)-termed cerebral autoregulation (CA)-bedside monitoring of cerebral perfusion and oxygenation could help guide BP management, thereby improve stroke patient outcome. The aim of INFOMATAS is to 'identify novel therapeutic targets for treatment and management in acute ischemic stroke'. In this review, we identify novel physiological parameters which could be used to guide BP management in acute stroke, and explore methodologies for monitoring them at the bedside. We outline the challenges in translating these potential prognostic markers into clinical use.

24-hour blood pressure variability and treatment effect of intravenous alteplase in acute ischaemic stroke

Introduction

To assess the association between 24 h blood pressure variability (BPV) on functional outcome and treatment effect of intravenous alteplase in acute ischaemic stroke.

Patients and methods

In all patients with acute ischaemic stroke of unknown onset randomised in the WAKE-UP (Efficacy and Safety of magnetic resonance imaging [MRI]-based Thrombolysis in Wake-Up Stroke) trial, blood pressure (BP) was measured before randomisation and after initiation of treatment at regular intervals up to 24 hours. Individual BPV was measured by coefficient of variation (CV) of all BP values. Primary outcome measure was favourable outcome defined by a modified Rankin Scale (mRS) score 0 or 1 at 90 days after stroke.

Results

BP measurements were available for 498 of 503 patients randomised (177 women [35.5%], mean age [SD] of 65.2 [11.5] years). Systolic BPV was not associated with the treatment effect of thrombolysis (test for interaction, p = 0.46). The adjusted odds ratio (aOR) for favourable outcome with alteplase, adjusted for age, stroke severity and baseline BP on admission, did not show an association across the quintiles of increasing systolic BPV with an aOR 1.89 (95% confidence interval [CI], 0.76-4.70) in the lowest quintile to aOR 1.05 (95% CI, 0.43-2.56) in the highest quintile. Higher mean systolic BP was associated with a smaller treatment effect of thrombolysis with a significant interaction (p = 0.033). The aOR for favourable outcome with alteplase decreased with quintiles of increasing mean systolic BP from aOR 3.16 (95% CI, 1.26-7.93) in the lowest quintile to aOR 0.84 (95% CI, 0.34-2.10) in in the highest quintile.

Conclusions

There was a significant interaction between mean systolic BP and treatment effect of thrombolysis with higher mean systolic BP being associated with poorer outcome. BPV was not associated with outcome after thrombolysis.ClinicalTrials.gov identifier NCT01525290.

Sugar-sweetened soft drink consumption acutely decreases spontaneous baroreflex sensitivity and heart rate variability

In healthy humans, fructose-sweetened water consumption increases blood pressure variability (BPV) and decreases spontaneous cardiovagal baroreflex sensitivity (cBRS) and heart rate variability (HRV). However, whether consuming commercially available soft drinks containing high levels of fructose elicits similar responses is unknown. We hypothesized that high-fructose corn syrup (HFCS)-sweetened soft drink consumption increases BPV and decreases cBRS and HRV to a greater extent compared with artificially sweetened (diet) and sucrose-sweetened (sucrose) soft drinks and water. Twelve subjects completed four randomized, double-blinded trials in which they drank 500 mL of water or commercially available soft drinks matched for taste and caffeine content. We continuously measured beat-to-beat blood pressure (photoplethysmography) and R-R interval (ECG) before and 30 min after drink consumption during supine rest for 5 min during spontaneous and paced breathing. BPV was evaluated using standard deviation (SD), average real variability (ARV), and successive variation (SV) methods for systolic and diastolic blood pressure. cBRS was assessed using the sequence method. HRV was evaluated using the root mean square of successive differences (RMSSD) in R-R interval. There were no differences between conditions in the magnitude of change from baseline in SD, ARV, and SV (P ≥ 0.07). There were greater reductions in cBRS during spontaneous breathing in the HFCS (-3 ± 5 ms/mmHg) and sucrose (-3 ± 5 ms/mmHg) trials compared with the water trial (+1 ± 5 ms/mmHg, P < 0.03). During paced breathing, HFCS evoked greater reductions in RMSSD compared with water (-26 ± 34 vs. +2 ± 26 ms, P < 0.01). These findings suggest that sugar-sweetened soft drink consumption alters cBRS and HRV but not BPV.

Optimal blood pressure levels in different phases of peripheral thrombolysis period in acute ischemic stroke

BACKGROUND

Dramatic changes of blood pressure (BP) were observed in the peripheral thrombolysis period, however, there is no consensus about BP control targets in the different phases.

METHODS

We retrospectively studied a consecutive sample of 510 patients treated with intravenous thrombolysis and followed-up for 3 months. The peripheral thrombolysis period was divided into these phases: Phase 1 (from onset to thrombolysis), Phase 2 (thrombolysis), Phase 3 (from thrombolysis to 24 h after thrombolysis), and Phase 4 (from 24 h to 7 days after thrombolysis). Patients were divided into quintiles according to mean blood pressure in these phases, respectively. Neurological improvement was evaluated using the modified Rankin Scale score at 3-month after thrombolysis.

RESULTS

Lower risk of intracerebral hemorrhage within 7 days was found in lower quintiles of SBP (OR = 0.100, 95% CI 0.011-0.887, P = 0.039 in Phase 1 quintile Q1, OR = 0.110, 95% CI 0.012-0.974, P = 0.047 in Phase 2-3 quintile Q1, and OR, 0.175, 95% CI, 0.035-0.872; P = 0.033 in Phase 4 quintile Q2, respectively). Better neurological improvement was found in SBP quintiles: Q2-Q4 (127.3-155.7 mmHg) in Phase 4 (OR = 3.095, 95% CI 1.524-6.286, P = 0.002 for Q2; OR = 2.697, 95% CI 1.354-5.370, P = 0.005 for Q3; and OR = 2.491, 95% CI 1.263-4.913, P = 0.008 for Q4, respectively). Our results also showed higher average real variability of SBP was negatively associated with better neurological outcome in Phase 1 and Phase 2-3.

CONCLUSIONS

Maintaining SBP levels (≤148 mmHg) from admission to the first 24 h after thrombolysis, then keeping SBP levels (127-138 mmHg) would be beneficial.

Blood pressure variability and outcome in acute severe stroke: A post hoc analysis of CHASE-A randomized controlled trial

The influence of blood pressure variability (BPV) on outcomes in patients with severe stroke is still largely unsettled. Using the data of CHASE trial, the authors calculated the BPV during the acute phase and subacute phase of severe stroke, respectively. The primary outcome was to investigate the relationship between BPV and 90‐day modified Rankin scale (mRS) ≥ 3. The BPV was assessed by eight measurements including standard deviation (SD), mean, maximum, minimum, coefficient of variation (CV), successive variation (SV), functional successive variation (FSV), and average real variability (ARV). Then, the SD of SBP was divided into quintiles and compared the quintile using logistic regression in three models. The acute phase included 442 patients, and the subacute phase included 390 patients. After adjustment, six measurements of BPV during the subacute phase rather than acute phase were strongly correlated with outcomes including minimum (odds ratio [OR]: 0.83, 95% confidence interval [CI]: 0.69‐0.99, p = .037), SD (OR: 1.10, 95% CI: 1.03‐1.17, p = .007), CV (OR: 1.12, 95% CI: 1.03‐1.23, p = .012), ARV (OR: 1.13, 95% CI: 1.05‐1.20, p < .001), SV (OR: 1.09, 95% CI: 1.04‐1.15, p = .001), and FSV (OR: 1.12, 95% CI: 1.05‐1.19, p = .001). In the logistic regression, the highest fifth of SD of SBP predicted poor outcome in all three models. In conclusion, the increased BPV was strongly correlated with poor outcomes in the subacute phase of severe stroke, and the magnitude of association was progressively increased when the SD of BP was above 12.

Day-by-Day Blood Pressure Variability Is Associated With Neurological Functional Outcome After Acute Ischemic Stroke

Background: Increased blood pressure variability (BPV) might be a detrimental factor after acute ischemic stroke. Previous studies on the association between blood pressure variability in the acute ischemic stroke and functional outcome have yielded inconsistent results. We aimed to investigate the impact of day-by-day blood pressure variability within 7 days of onset on functional outcome at 3 months after acute ischemic stroke.

Methods: Total 367 patients hospitalized for ischemic stroke within 48 h of onset were enrolled. The acute stage of ischemic stroke was defined as the time period from symptom onset to 7 days. During this period, blood pressure was measured twice daily (respectively, in the morning during 8:00 a.m.−10:00 a.m., in the afternoon between 15:00 p.m. and 17:00 p.m.). Day-by-day blood pressure variability, including standard deviation (SD) and coefficient variation (CV) were derived and compared to functional outcome. We dichotomized function outcome according to mRS score and unfavorable outcome was defined as mRS ≥3.

Results: The patients with unfavorable outcome had significantly higher systolic BPV (within 7 days of onset) than those with favorable outcome (15.41 ± 4.59 vs. 13.42 ± 3.95 mmHg for SD, P < 0.001; 11.54 ± 3.23 vs. 10.41 ± 2.82 for CV, P = 0.001). Multivariable logistic regression analysis revealed that systolic BPV was significantly and independently associated with the 3-month functional outcome [odds ratio (OR) = 1.15, 95% confidence interval (CI): 1.07–1.22, P < 0.001 for SD; OR = 1.15, 95% CI: 1.06–1.26, P = 0.001 for CV]. In addition, After adjustment for multiple confounding factors, including age, gender, risk factors, stroke features, baseline severity, recanalized therapy, hemorrhagic transformation, pulmonary infection, white blood cell, estimated Glomerular Filtration Rate and mean BP, day-by-day BP variability was significantly correlated with an unfavorable outcome in the top vs. bottom quartile of systolic BPV (OR = 3.33, 95% CI: 1.41–7.85, P = 0.006 for SD; OR = 2.27, 95% CI: 1.04–4.94, P = 0.037 for CV) during 3-month follow-up. Similar trends were also observed for diastolic BPV. More importantly, incorporating SD of systolic BP into the conventional prediction model could significantly increase the AUC for prediction of 3-month unfavorable outcome after acute ischemic stroke (0.84 vs. 0.86; P = 0.0416).

Conclusions: Increased day-by-day blood pressure variability of systolic or diastolic BP in the acute ischemic stroke was associated with higher risk for unfavorable outcome at 3 months independent of blood pressure levels. Combining SD of systolic BP with conventional risk factors could improve the prediction of unfavorable outcome.

Dietary nitrate reduces blood pressure and cerebral artery velocity fluctuations and improves cerebral autoregulation in transient ischemic attack patients

We found dietary nitrate supplementation reduced blood pressure and brain blood flow fluctuations and improved the relationship between blood pressure and brain blood flow in transient ischemic attack patients. Meanwhile, dietary nitrate had no effects on the brain blood vessels’ response to CO2. We attribute the improved brain blood flow stability to the improved myogenic control of blood pressure with dietary nitrate. Our findings indicate that dietary nitrate could be an effective strategy for stabilizing blood pressure and brain blood flow following transient ischemic attack.

Blood pressure variability and outcome after acute intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is life threatening neurologic event that results in significant rate of morbidity and mortality. Unfortunately, several randomized clinical trials aiming at limiting the hematoma expansion (HE) in the acute phase of ICH have not shown significant effects in improving the functional outcomes. Blood pressure variability (BPV) is common following ICH. High BPs have been associated with increased risk of bleeding and HE. Conversely, recurrent sudden decrease in BP promote perihematomal ischemia. However, it is still not clear weather BPV causes adverse prognosis following ICH or large ICHs cause fluctuations in BP. In the current review, we will discuss the mechanistic pathophysiology of BPV and the evidence regarding the role of BPV on the ICH outcomes.

Increased blood pressure variability during the subacute phase of ischemic stroke is associated with poor functional outcomes at 3 months

Thus far, it is well known that increased blood pressure variability may exacerbate stroke outcomes. Blood pressure in the acute phase would be influenced by both reactive hypertension to stroke and intrinsic blood pressure reactivity. Thus, we aimed to evaluate the association between blood pressure variability and outcomes at 3 months using ambulatory blood pressure monitoring in ischemic stroke patients in the subacute phase after reactive hypertension subsided. We retrospectively examined 626 consecutive patients with acute ischemic stroke who underwent 24-hour ambulatory blood pressure monitoring during the subacute phase of stroke (median, 9 days from onset). The variability in blood pressure was evaluated by assessing the standard deviation and coefficient of variation of systolic and diastolic blood pressure. The primary outcome was functional status at 3 months. A poor outcome was defined as a modified Rankin scale score of 3 or more and a good outcome as 2 or less. We assessed the functional outcome at 3 months in 497 patients (79.4%). The mean systolic and diastolic blood pressure levels were not associated with functional outcome. The multivariable analysis revealed that increases in the standard deviations of systolic and diastolic blood pressure, coefficient of variation of diastolic blood pressure, and morning blood pressure surge were associated with poor outcome. Blood pressure variability during the subacute phase of ischemic stroke can be a useful prognostic indicator of poor functional outcome at 3 months in patients with acute ischemic stroke.

Associations of various blood pressure parameters with functional outcomes after endovascular thrombectomy in acute ischaemic stroke

BACKGROUND AND PURPOSE

High blood pressure (BP) at presentation is associated with poor outcomes in acute ischaemic stroke, but serial BP measurements may better delineate the clinical implications of BP. The aim was to investigate the association between various BP parameters and functional outcomes in acute ischaemic stroke patients treated with endovascular thrombectomy (EVT).

METHODS

This study reports a retrospective analysis of a prospective registry of a comprehensive stroke centre. Patients treated with EVT due to large vessel occlusion in the anterior circulation were enrolled. BP was measured hourly during the first 24 h after admission. Associations of various BP parameters, including BP variability, with functional outcomes at 3 months, including good outcomes (modified Rankin Scale score of 0-2), were analysed.

RESULTS

Of the 378 enrolled patients (mean age 70 ± 11 years, male 54.2%), 313 (82.8%) achieved successful reperfusion after EVT, and 149 (39.4%) had good outcomes at 3 months. Higher mean systolic BP [each 10 mmHg increase, odds ratio 0.82 (0.69-0.97)] and higher systolic successive variation (SV) [each 10% increase, odds ratio 0.37 (0.18-0.76)] were associated with a reduced likelihood of achieving good outcomes. In addition, reperfusion status after EVT moderated the influence of higher systolic SV on good outcomes (P_int  = 0.05).

CONCLUSION

The results showed that a higher mean systolic BP and systolic SV during the first 24 h of EVT reduced the likelihood of good outcomes at 3 months. The effects of these parameters on outcomes are more substantial amongst patients with successful reperfusion after EVT, suggesting that different BP control strategies should be employed according to reperfusion status.

Blood pressure variability and hemorrhagic transformation in patients with successful recanalization after endovascular recanalization therapy: A retrospective observational study

OBJECTIVE

Although blood pressure (BP) variability has been regarded as a risk factor for hemorrhagic transformation (HTF) after intravenous thrombolysis, its effect on HTF after endovascular recanalization therapy (ERT) remains to be elucidated. We aimed to study the relationship between BP variability and symptomatic intracerebral hemorrhage (sICH) after successful recanalization with ERT.

METHODS

A total of 211 patients with acute ischemic stroke and successful recanalization (thrombolysis in cerebral infarction 2b or 3) after ERT were included between January 2013 and May 2017. The BP data following ERT was obtained over the first 24 hours using parameters including mean, maximum, minimum, difference between maximum and minimum, standard deviation, coefficient of variation, successive variations, and time rate (TR) of BP variation for systolic BP (SBP) and diastolic BP. sICH was defined as parenchymal hemorrhage type 2 with neurological deterioration of 4 points of more on the National Institute of Health Stroke Scale.

RESULTS

Among the included patients, 20 (9.5%) developed sICH after successful ERT. The parameters linked with BP fluctuation over time were significantly related to sICH. After adjusting for confounders, the TR of SBP (per 0.1 mmHg/min increase) variation was independently associated with sICH (odds ratio = 1.71, 95% confidence interval = 1.013-2.886).

INTERPRETATION

Time-related BP variability in the first 24 hours following successful ERT was more correlated with sICH than other absolute BP levels. This suggests that maintaining a stable BP may be an important factor in preventing sICH after successful ERT. Ann Neurol 2019;85:574-581.

Association of Elevated Blood Pressure Levels with Outcomes in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Although arbitrary blood pressure (BP) thresholds exist for acute ischemic stroke (AIS) patients eligible for intravenous thrombolysis (IVT), current international recommendations lack clarity on the impact of mean pre- and post-IVT BP levels on clinical outcomes.

METHODS

Eligible studies involving IVT-treated AIS patients were identified that reported the association of mean systolic BP (SBP) or diastolic BP levels before and after IVT with the following outcomes: 3-month favorable functional outcome (modified Rankin Scale [mRS] scores of 0-1) and 3-month functional independence (mRS scores of 0-2), 3-month mortality and symptomatic intracranial hemorrhage (sICH). Unadjusted analyses of standardized mean differences and adjusted analyses of studies reporting odds ratios (ORadj) per 10 mm Hg BP increment were performed using random-effects models.

RESULTS

We identified 26 studies comprising 56,513 patients. Higher pre- (P=0.02) and posttreatment (P=0.006) SBP levels were observed in patients with sICH. Patients with 3-month functional independence had lower post-treatment (P<0.001) SBP whereas trended towards lower pre-treatment (P=0.06) SBP. In adjusted analyses, elevated pre- (ORadj, 1.08; 95% confidence interval [CI], 1.01 to 1.16) and post-treatment (ORadj, 1.13; 95% CI, 1.01 to 1.25) SBP levels were associated with increased likelihood of sICH. Increasing pre- (ORadj, 0.91; 95% CI, 0.84 to 0.98) and post-treatment (ORadj, 0.70; 95% CI, 0.57 to 0.87) SBP values were also related to lower odds of 3-month functional independence.

CONCLUSION

s We found that elevated BP levels adversely impact AIS outcomes in patients receiving IVT. Future randomized-controlled clinical trials will provide definitive data on the aforementioned association.

Dietary nitrate supplementation reduces low frequency blood pressure fluctuations in rats following distal middle cerebral artery occlusion

It is known that high blood pressure variability (BPV) in acute ischemic stroke is associated with adverse outcomes, yet there are no therapeutic treatments to reduce BPV. Studies have found increasing nitric oxide (NO) bioavailability improves neurological function following stroke, but whether dietary nitrate supplementation could reduce BPV remains unknown. We investigated the effects of dietary nitrate supplementation on heart rate (HR), blood pressure (BP), and beat-to-beat BPV using wireless telemetry in a rat model of distal middle cerebral artery occlusion. Blood pressure variability was characterized by spectral power analysis in the low frequency (LF; 0.2–0.6 Hz) range prestroke and during the 7 days poststroke in a control group ( n = 8) and a treatment group ( n = 8, 183 mg/l sodium nitrate in drinking water). Dietary nitrate supplementation moderately reduced systolic BPV in the LF range by ~11% compared with the control group ( P = 0.03), while resting BP and HR were not different between the two groups ( P = 0.28 and 0.33, respectively). Despite systolic BPV being reduced with dietary nitrate, we found no difference in infarct volumes between the treatment and the control groups (1.59 vs. 1.62 mm3, P = 0.86). These findings indicate that dietary nitrate supplementation is effective in reducing systolic BPV following stroke without affecting absolute BP. In light of mounting evidence linking increased BPV with poor stroke patient outcome, our data support the role of dietary nitrate as an adjunct treatment following ischemic stroke.

NEW & NOTEWORTHY Using a rat model of stroke, we found that dietary nitrate supplementation reduced low frequency blood pressure fluctuations following stroke without affecting absolute blood pressure values. Since blood pressure fluctuations are associated with poor clinical outcome in stroke patients, our findings indicate that dietary nitrate could be an effective strategy for reducing blood pressure fluctuations, which could help reduce stroke severity and improve patient recovery.

Blood pressure variability estimated by ARV is a predictor of poor short-term outcomes in a prospective cohort of minor ischemic stroke

Prior studies have shown that patients with minor ischemic stroke have substantial disability rates at hospital discharge. We sought to determine whether blood pressure variability (BPV) estimated by average real variability (ARV) is one of the predictors of poor outcome at 90 days. Four hundred fifty-one consecutive patients with ischemic stroke treated within 7 days after onset were enrolled prospectively. Baseline magnetic resonance imaging (MRI) was performed on all subjects. Blood pressure was measured for all recruited patients every 2 hours in the first 24 hours after admission, followed by measurements collected every 4 hours from day 2 to day 7 after admission. ARV was used to estimate BPV. A total of 192 patients with minor ischemic stroke were enrolled, and 11 of them (5.7%) had poor outcomes. Univariate regression analysis showed that early neurological deterioration (X² = 21.44, P = 0.000), severe symptomatic large artery stenosis or occlusion (X² = 9.260, P = 0.000), large artery atherosclerotic stroke (X² = 7.14, P = 0.002), total cholesterol (TC), and D2-7 SBP-ARV (t = 5.449, P = 0.001) of the poor outcome group were significantly higher than those of the good outcome group. Multivariate logistic regression analysis showed that early neurological deterioration (OR 4.369, 95% CI 3.54, 15.65; P = 0.001), severe symptomatic large artery stenosis or occlusion (OR 5.56, 95% CI 3.56, 13.65; P = 0.000), large artery atherosclerotic stroke (OR 3.56, 95% CI 1.45, 7.48; P = 0.004), and D2-7 SBP-ARV (OR 3.96, 95% CI 1.90, 20.18, P = 0.008) were significantly related to poor outcomes. In conclusion, approximately 5.7% of minor ischemic stroke patients had poor outcomes. D2-7 SBP-ARV, early neurologic deterioration, severe symptomatic artery stenosis or occlusion, and large atherosclerotic stroke were the independent risk factors of poor short-term outcomes.

High serum uric acid levels are a protective factor against unfavourable neurological functional outcome in patients with ischaemic stroke

Objective

We aimed to evaluate the association between serum uric acid levels at the onset and prognostic outcome in patients with acute ischaemic stroke.

Methods

We retrospectively analysed the outcomes of 1166 patients with ischaemic stroke who were hospitalized in our centre during August 2008 to November 2012. Correlations of serum uric acid levels and prognostic outcomes were analysed.

Results

Men had higher serum uric acid levels and better neurological functional outcomes compared with women. There was a strong negative correlation between serum uric acid levels and unfavourable neurological functional outcomes. Generalized estimated equation analysis showed that a higher serum uric acid level (>237 µmol/L) was a protective factor for neurological functional outcome in male, but not female, patients. Among five trial of ORG 10172 in acute stroke treatment classification subtypes, only patients with the large-artery atherosclerosis subtype had a significant protective effect of serum uric acid levels on neurological outcome.

Conclusions

Our study shows that high serum uric acid levels are a significant protective factor in men and in the large-artery atherosclerosis subtype in patients with ischaemic stroke. This is helpful for determining the prognostic value of serum uric acid levels for neurological outcome of acute ischaemic stroke.

Association Between Hyperacute Stage Blood Pressure Variability and Outcome in Patients With Spontaneous Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Increased blood pressure (BP) variability, in addition to high BP, may contribute to adverse outcome in intracerebral hemorrhage. However, degree and association with outcome of BP variability (BPV) in the hyperacute period, 15 minutes to 5 hours after onset, have not been delineated.

METHODS

Among consecutive patients with intracerebral hemorrhage enrolled in the FAST-MAG trial (Field Administration of Stroke Therapy-Magnesium), BPs were recorded by paramedics in the field and during the first 24 hours of hospital course. BP was analyzed in the hyperacute period, from 0 to 4-6 hours, and in the acute period, from 0 to 24-26 hours after onset. BPV was analyzed by SD, coefficient of variation, and successive variation.

RESULTS

Among 386 patients with intracerebral hemorrhage, first systolic BP at median 23 minutes (interquartile range, 14-38.5) after onset was median 176 mm Hg, second systolic BP on emergency department arrival at 57 minutes (interquartile range, 45-75) after onset was 178 mm Hg, and systolic BP 24 hours after arrival was 138 mm Hg. Unfavorable outcome at 3 months (modified Rankin Scale, 3-6) occurred in 270 (69.9%). Neither mean nor maximum systolic BP was associated with outcome in multivariable analysis. However, all 3 parameters of BPV, in both the hyperacute and the acute stages, were associated with poor outcome. In the hyperacute phase, BPV was associated with poor outcome with adjusted odds ratios of 3.73 for the highest quintile of SD, 4.78 for the highest quintile of coefficient of variation, and 3.39 for the highest quintile of successive variation.

CONCLUSIONS

BPV during the hyperacute first minutes and hours after onset in patients with intracerebral hemorrhage was independently associated with poor functional outcome. Stabilization of BPV during this vulnerable period, in the pre-hospital and early emergency department course, is a potential therapeutic target for future clinical trials.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.

Ambulatory blood pressure variability within the first 24 hours after admission and outcomes of acute ischemic stroke

Our purpose was to evaluate the value of blood pressure variability within the first 24 hours after admission in predicting outcomes of patients with acute ischemic stroke (AIS). A greater variability in systolic blood pressure (adjusted odds ratio [OR] = 1.801, 95% confidence interval [CI] = 1.167-2.779) was associated with poor discharge outcome, especially for nondiabetics (adjusted OR = 1.948, 95% CI = 1.184-3.205) and cardioembolism-related patients with AIS (OR = 7.650, 95% CI = 1.370-42.713). However, this correlation was not observed with a long-term (3-month or 6-month) outcome in patients with AIS. There was no association between diastolic blood pressure variability within the first 24 hours after admission and outcome. In conclusion, systolic blood pressure variability within the first 24 hours after admission is a critical predictor for short-term outcome of patients with AIS.

Blood pressure evolution in young patients with acute ischemic stroke: a new model for understanding the natural course of spontaneous hypertension?

BACKGROUND

Approximately 80% of patients suffering an acute ischemic stroke develop transient hypertension. The physiopathological mechanism remains unclear. Due to the lack of vascular risk factors, young adults could be a useful model for understanding blood pressure (BP) evolution in this setting.

METHODS

Patients between 18 and 55 years old admitted with an acute ischemic stroke were included. BP was evaluated during the following 48 h. Hypertension was defined as: systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥90 mmHg. Patients were divided into two groups: RF group included those who had a previous vascular risk factor and/or other medical condition known to affect the autonomic function; noRF group included patients without any of the previously stated conditions.

RESULTS

Thirty-nine patients were included: mean age: 44.26 years old, 21 were males (53.8%). Mean SBP and DBP at admission were 139.77 ± 5.35 mmHg (range: 90-243) and 84.44 ± 3.02 mmHg (range: 60-128), respectively; 43.58% patients were hypertensive at admission. SBP decreased significantly during the first 48 h (p = 0.044) for the entire population. RF group has higher SBP (p = 0.009) and DBP (p = 0.011) at admission than the noRF group.

CONCLUSION

Most patients were normotensive at admission and BP fell spontaneously despite BP at admission. Young patients without medical conditions that could alter the autonomic system function could be a useful model for understanding acute hypertension in ischemic stroke.

Association between beat-to-beat blood pressure variability and vascular elasticity in normal young adults during the cold pressor test

The beat-to-beat blood pressure (BP) monitoring parameters, such as average beat-to-beat BP, BP variability (BPV), could have an influence on the vascular elasticity. This study hypothesized that the elevated beat-to-beat BPV could evoke the reduction of the vascular elasticity independent of BP levels. We measured the beat-to-beat BP recordings and total arterial compliance (TAC), which was used to assess the vascular elasticity, in 80 young healthy adults during the cold pressor test (CPT). The CPT included 3 phases: baseline phase, cold stimulus phase, recovery phase. Six parameters were used to estimate BPV. In bivariate correlation analysis, TAC showed a significant correlation with systolic BP (SBP) and diastolic BP (DBP) in the cold stimulus phase; and 4 indices of SBP variability (SBPV) were associated with TAC (r = 0.271∼0.331, P ≤ 0.015) in the recovery phase; similarly, 2 indices of DBP variability (DBPV) were also correlated with TAC (r = 0.221∼0.285, P ≤ 0.048) in the recovery phase. In multivariate regression analysis, DBPV (β = 0.229, P = 0.001) was a determinant of TAC independent of average DBP, sex, and weight. In addition, both beat-to-beat BP and BPV values increased in the cold stimulus phase (P < 0.01); whereas, the TAC decreased in the cold stimulus phase (P < 0.01). In conclusion, these data suggest that the beat-to-beat DBPV shows an independent association with the vascular elasticity in young normal adults during the CPT.

No Association Observed Between Blood Pressure Variability During the Acute Phase of Ischemic Stroke and In-Hospital Outcomes

BACKGROUND

Recent data suggest that blood pressure (BP) variability confers increased cardiovascular risk independently of BP. We aimed to evaluate the association between BP variability during the acute phase of ischemic stroke and the in-hospital outcome.

METHODS

We prospectively studied 608 consecutive patients admitted with acute ischemic stroke (39.5% males, age: 79.1±6.6 years). Variability in BP was assessed with the SD and with the coefficient of variation of systolic (SBP) and diastolic BP (DBP) during the first 2 and the first 3 days of hospitalization. The outcome was assessed with dependency rates at discharge and with in-hospital mortality.

RESULTS

Patients who were dependent at discharge did not differ from patients who were independent in any index of BP variability. Independent predictors of dependency at discharge were age (relative risk (RR) 1.17, 95% confidence interval (CI) 1.09-1.25, P < 0.001), history of prior ischemic stroke (RR 2.08, 95% CI 1.02-4.24, P = 0.04), and National Institutes of Health Stroke Scale (NIHSS) at admission (RR 1.64, 95% CI 1.44-1.86, P < 0.001). Patients who died during hospitalization did not differ in any index of BP variability from patients who were discharged. DBP at admission was independently and directly associated with in-hospital mortality (RR 1.06, 95% CI 1.03-1.09, P < 0.001). Other independent predictors of in-hospital mortality were history of atrial fibrillation (RR 3.30, 95% CI 1.46-7.49, P = 0.004) and NIHSS at admission (RR 1.18, 95% CI 1.13-1.23, P < 0.001).

CONCLUSIONS

Our data do not support the hypothesis of an association between BP variability and in-hospital outcomes among patients admitted for ischemic stroke.

Temporal profiles of blood pressure, circulating nitric oxide, and adrenomedullin as predictors of clinical outcome in acute ischemic stroke patients

Stroke remains an important health and social challenge. The present study investigated whether blood pressure (BP) parameters and circulating levels of nitric oxide metabolites (NOx) and adrenomedullin (AM) may predict clinical outcomes of stroke. Patients (n=76) diagnosed with acute ischemic stroke were admitted to the stroke unit and clinical history data and monitored parameters were recorded. Blood plasma was collected at days 1, 2, and 7 to measure NOx and AM levels. Infarct volume, neurological severity [on the National Institutes of Health Stroke Scale (NIHSS)], and functional prognosis (on the Rankin scale) were measured as clinical outcomes. Patients with higher BP had more severe symptoms (NIHSS >3; P<0.01) and BP variability predicted neurological severity and growth of infarct volume. NOx values were significantly lower in stroke patients than in healthy controls (P<0.01). An increase in NOx levels from day 1 to day 2 was beneficial for the patients as measured by NIHSS at 7 days and 3 months, and by Rankin at 3 months [odds ratio (OR), 0.91] whereas a steep increase from day 2 to day 7 was detrimental and associated with an increase in infarct volume (OR, 35.3). AM levels were significantly higher in patients at day 1 and 2 than in healthy individuals (P<0.01) and these levels returned to normal at day 7. Patients with high AM levels at day 2 had significantly higher NIHSS scores measured at day 1 (P<0.05) and 7 (P<0.01). A receiving operating characteristic curve analysis identified that AM levels at day 2 of >522.13 pg/ml predicted increased neurological severity at day 7 (area under the curve=0.721). Multivariate logistic regression indicated that AM levels at day 2 predicted increased neurological severity at 7 days and at 3 months. BP parameters and changing levels for NOx and AM predicted long-term clinical outcomes as measured by infarct volume, neurological severity scale, and functional prognosis.

Lower Intraprocedural Systolic Blood Pressure Predicts Good Outcome in Patients Undergoing Endovascular Therapy for Acute Ischemic Stroke

BACKGROUND

It is unknown if intraprocedural blood pressure (BP) influences clinical outcomes and what BP parameter best predicts outcomes in acute ischemic stroke (AIS) patients who undergo intra-arterial therapy (IAT) for emergent large vessel occlusion.

METHODS

We retrospectively reviewed 147 patients who underwent IAT for anterior circulation AIS from January 2008 to December 2012 at our institution. Baseline demographics, stroke treatment variables, and detailed intraprocedural hemodynamic variables were collected.

RESULTS

The entire cohort consisted of 81 (55%) females with a mean age of 66.9 ± 15.6 years and a median National Institutes of Health Stroke Scale (NIHSS) score of 16 (IQR 11-21). Thirty-six (24.5%) patients died during hospitalization, 25 (17%) achieved a 30-day modified Rankin Scale score of 0-2, and 24 (16.3%) suffered symptomatic parenchymal hematoma type 1/2 hemorrhage. Patients who achieved a good outcome had a significantly lower admission NIHSS score, a higher baseline CT ASPECTS score, and a lower rate of ICA terminus occlusions. Successful recanalization was more frequent in the good-outcome group, while symptomatic hemorrhages occurred only in poor-outcome patients. The first systolic BP (SBP; 146.5 ± 0.2 vs. 157.7 ± 25.6 mm Hg, p = 0.042), first mean arterial pressure (MAP; 98.1 ± 20.8 vs. 109.7 ± 20.3 mm Hg, p = 0.024), maximum SBP (164.6 ± 27.6 vs. 180.9 ± 18.3 mm Hg, p = 0.0003), and maximum MAP (125.5 ± 18.6 vs. 138.5 ± 24.6 mm Hg, p = 0.0309) were all significantly lower in patients who achieved good outcomes. A lower maximum intraprocedural SBP was an independent predictor of good outcome (adjusted OR 0.929, 95% CI 0.886-0.963, p = 0.0005). Initial NIHSS score was the only other independent predictor of a good outcome.

CONCLUSION

Lower intraprocedural SBP was associated with good outcome in patients undergoing IAT for AIS, and maximum SBP was an independent predictor of good outcome. SBP may be the optimal hemodynamic variable to monitor intraprocedurally during IAT and may predict outcome.

Prognostic Significance of Short-Term Blood Pressure Variability in Acute Stroke

Background and Purpose—

Blood pressure variability (BPV) may be an important prognostic factor acutely after stroke. This review investigated the existing evidence for the effect of BPV on outcome after stroke, also considering BPV measurement techniques and definitions.

Methods—

A literature search was performed according to a prespecified study protocol. Two reviewers independently assessed study eligibility and quality. Where appropriate, meta-analyses were performed to assess the effect of BPV on poor functional outcome.

Results—

Eighteen studies from 1359 identified citations were included. Seven studies were included in a meta-analysis for the effect of BPV on functional outcome (death or disability). Systolic BPV was significantly associated with poor functional outcome: pooled odds ratio per 10-mm Hg increment, 1.2; confidence interval (1.1–1.3). A descriptive review of included studies also supports these findings, and in addition, it suggests that systolic BPV may be associated with increased risk of intracranial hemorrhage in those treated with thrombolytic therapy.

Conclusions—

This systematic review and meta-analysis suggest that greater systolic BPV, measured early from ischemic stroke or intracerebral hemorrhage onset, is associated with poor longer-term functional outcome. Future prospective studies should investigate how best to measure and define BPV in acute stroke, as well as to determine its prognostic significance.

Prognostic Value of 24-H ABPM in Acute Ischemic Stroke for Short-, Medium-, and Long-Term Outcome: A Systematic Review and Meta-Analysis

Background

The association of blood pressure levels during the acute phase of ischemic stroke with outcome remains controversial.

Aims

The objective of this systematic review is to assess the predictive value for stroke outcome assessed by the modified Rankin scale score of systolic and diastolic blood pressure, measured by ambulatory blood pressure monitoring methods during the acute phase of ischemic stroke, compared with the values of casually derived blood pressure measurement on admission.

Methods

We searched for studies with patients admitted within 24 h of stroke onset, and who had ambulatory blood pressure monitoring during the first 24 h of admission. We identified studies that reported blood pressure in those with good outcome and in those with poor outcome at end of follow-up, and performed a meta-analysis of the effect of mean blood pressure on outcome.

Results

High systolic and diastolic blood pressure levels derived with ambulatory blood pressure monitoring were associated with poor short-, medium-, and long-term outcome, but the same was not found for casual blood pressure measurements. An increase in systolic blood pressure of 9·1 mmHg (95% confidence interval: 6·6–11·6, P < 0·001; I2 = 9%) and an increase in diastolic blood pressure of 2·3 mmHg (95% confidence interval: 0·8–3·7, P = 0·002; I2 = 0%) were associated with poor outcome.

Conclusions

Higher systolic and diastolic blood pressure levels derived with ambulatory blood pressure monitoring were associated with poor outcome. The same was not found for higher casual blood pressure measurements on admission, and it is possible that ambulatory blood pressure monitoring conveys better prognostic information.

Dynamic analysis of blood pressure changes in progressive cerebral infarction

BACKGROUND

Progressive cerebral infarction is one of the leading causes of high disability and lethality for stroke patients. However, the association between progression of BP changes and cerebral infarction is not currently well understood.

METHODS

We analyzed the dynamic changes in the BP of patients with acute ischemic stroke and explored the correlation between BP change and cerebral infarction progression.

RESULTS

30.9% (30/97) of the patients investigated developed to progressive cerebral infarction 17-141 h after admission. The percentage of patients with a long history of hypertension was significantly higher in the progressive group than in the non-progressive group. The mean systolic BP of the patients 16 h to 5 d after admission was also much higher in the progressive group. A greater abnormality of circadian blood pressure was also observed among patients in the progressive group.

CONCLUSIONS

Hypertension history of more than 5 years is an important risk factor for progressive cerebral infarction. Both the elevation of systolic blood pressure 16 h to 5 d after admission and abnormal circadian blood pressure are associated with the disease progression.