Interventions for deliberately altering blood pressure in acute stroke

Association of baseline blood pressure and outcomes in etiology subtypes of large vessel occlusion stroke: Data from ANGEL-ACT registry

BACKGROUND

Blood pressure (BP) management at the initial stage of stroke caused by large-vessel occlusion (LVO) remains challenging. We assessed the association between baseline BP and clinical and safety outcomes of endovascular treatment (EVT) in different stroke etiologies.

METHODS

Patients with acute ischemic stroke and anterior circulation LVO were screened from a prospective, multicenter registry of EVT from November 2017 to March 2019. The primary outcome was poor 90-day outcome (modified Rankin Scale score 3-6). The safety outcome was 24 h post-procedure parenchymal hematoma (PH). The Trial of Org 101072 in Acute Stroke Treatment criteria were used for etiologic stroke classification. Restricted cubic spline and binary logistic regression analysis were performed to examine the association between study outcomes and natural log-transformed BP.

RESULTS

In subgroup analyses, a U-shaped correlation existed between baseline mean arterial pressure (MAP) and poor outcome in large-artery atherosclerosis stroke only. Higher MAP was an independent risk factor compared with a central reference value (≥ 133 mm Hg vs 96-115 mm Hg; adjusted OR [aOR], 2.50; 95 % CI, 1.09 to 5.71, P = 0.030). Whereas elevated MAP was associated with PH (aOR, 1.58; 95 % CI 1.04 to 2.39, P = 0.030 for a ln10-unit increase in natural log-transformed MAP) in the range <110 mm Hg exclusively for cardioembolic stroke.

CONCLUSION

Whether it is cause or epiphenomenon, baseline BP was associated with 90-day outcome in large-artery atherosclerosis stroke, whereas in cardioembolic stroke baseline BP was correlated with post-procedure PH within a certain range. Identifying these features based on etiological subtypes may offer a reference for BP management in acute LVO stroke.

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.

Minor stroke patients with mild-moderate diastolic blood pressure derive greater benefit from dual antiplatelet therapy

Not only systolic blood pressure (SBP) but also diastolic blood pressure (DBP) increases the risk of recurrence in the short- or long-term outcomes of stroke. The interaction between DBP and antiplatelet treatment for China stroke patients is unclear. This multicenter, observational cohort study included 2976 minor ischemic stroke patients. Patients accepted single antiplatelet therapy (SAPT) or dual antiplatelet therapy (DAPT) after arrival, and baseline DBP levels were trichotomized into <90 mmHg, 90-110 mmHg and ≥110 mmHg. We explore the interaction effect between antiplatelet therapy and DBP on 90-days composite vascular events. A total of 257 (8.6%) patients reached a composite vascular event during follow-up. The interaction term between DBP levels and treatment group (SAPT vs. DAPT) was significant (P for interaction = 0.013). DAPT's adjusted HR for composite events in patients with DBP between 90 and 110 mmHg was 0.56 (95% confidence interval, 0.36 0.88; P = 0.011) and DBP ≥ 110 mmHg was 4.35 (95% confidence interval, 1.11-19.94; P = 0.046). The association between treatment and DBP was still consistent after propensity score matching of the baseline characteristics. The interaction term of DBP ×  treatment was not significant for the safety outcomes of severe bleeding (P for interaction = 0.301) or hemorrhage stroke (P for interaction = 0.831). In this cohort study based on the real world, patients with a DBP between 90 and 110 mmHg received a greater benefit from 90 days of DAPT than those with lower and higher baseline DBP. REGISTRATION: ( https://www.chictr.org.cn ; Unique identifier: ChiCTR1900025214).

Burden of cerebral small vessel disease and changes of diastolic blood pressure affect clinical outcome after acute ischemic stroke

Elevated and low blood pressure (BP) may lead to poor functional outcome after ischemic stroke, which is conflicting. Hence, there must be another factor-such as cerebral small vessel disease (cSVD) -interacting with BP and thus, affecting outcome. Here, we investigate the relationship between BP and cSVD regarding outcome after stroke. Data of 423/503 stroke patients were prospectively analyzed. Diastolic (DBP) and systolic BP (SBP) were collected on hospital admission (BPad) and over the first 72 h (BP72h). cSVD-burden was determined on MR-scans. Good functional outcome was defined as a modified Rankin Scale score ≤ 2 at hospital discharge and 12 months thereafter. cSVD was a predictor of poor outcome (OR 2.8; p < 0.001). SBPad, DBPad and SBP72h were not significantly associated with outcome at any time. A significant relationship was found between DBP72h, (p < 0.01), cSVD (p = 0.013) and outcome at discharge. At 12 months, we found a relationship between outcome and DBP72h (p = 0.018) and a statistical tendency regarding cSVD (p = 0.08). Changes in DBP72h were significantly related with outcome. There was a U-shaped relationship between DBP72h and outcome at discharge. Our results suggest an individualized stroke care by either lowering or elevating DBP depending on cSVD-burden in order to influence functional outcome.

Reperfusion status and postoperative blood pressure in acute stroke patients after endovascular treatment

Background and purpose

An aggressive lowering of blood pressure (BP) could lead to neurological worsening, particularly of the area that has not been reperfused in acute stroke patients with large vessel occlusion (LVO). We sought to investigate the association of reperfusion status and BP course following mechanical thrombectomy (MT) with outcomes in LVO.

Materials and methods

Consecutive patients with LVO treated with MT between Jan 2020 to Jun 2021 were enrolled in a retrospective cohort study. Hourly systolic BP (SBP) and diastolic BP (DBP) were recorded for 72 h following MT and maximum SBP and DBP levels were identified. The Extended Thrombolysis in Cerebral Infarction (eTICI) scale was used to assess reperfusion extent. LVO patients were stratified in 2 groups based on reperfusion status: complete reperfusion (eTICI 3) and incomplete reperfusion (eTICI 2b/c). Three-month functional independence was defined as a modified Rankin Scale score of 0-2.

Results

A total of 263 acute ischemic stroke patients with LVO were retrospectively evaluated. Complete reperfusion was achieved in 210 patients (79.8%). Post-MT maximum SBP over 160 mmHg was significantly related to worse functional outcome (38.1% vs. 55.7%, p = 0.006), higher likelihood of in-hospital mortality and 3-month mortality (19.0% vs. 6.9%, p = 0.004, 27.4% vs. 14.3%, p = 0.012). No statistical correlation was found between reperfusion status and blood pressure level (p > 0.05). In patients with complete reperfusion, patients with an average BP 120-140 mmHg tends to have worse functional outcome compared with 100-120 mmHg (OR = 1.77, 95%CI: 0.97-3.23, p = 0.061).

Conclusion

High maximum SBP levels following MT are associated with an increased likelihood of 3-month functional dependence and mortality. An average BP of 100-120 mmHg tends to have better functional independence in completely reperfused patients. The effect of intensive BP control on incomplete reperfusion still warrants further investigations.

Cerebrolysin for acute ischaemic stroke

BACKGROUND

Cerebrolysin is a mixture of low-molecular-weight peptides and amino acids derived from porcine brain, which has potential neuroprotective properties. It is widely used in the treatment of acute ischaemic stroke in Russia, Eastern Europe, China, and other Asian and post-Soviet countries. This is an update of a review first published in 2010 and last updated in 2020.

OBJECTIVES

To assess the benefits and harms of Cerebrolysin or Cerebrolysin-like agents for treating acute ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Trials Register, CENTRAL, MEDLINE, Embase, Web of Science Core Collection, with Science Citation Index, and LILACS in May 2022 and a number of Russian databases in June 2022. We also searched reference lists, ongoing trials registers, and conference proceedings.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing Cerebrolysin or Cerebrolysin-like agents started within 48 hours of stroke onset and continued for any length of time, with placebo or no treatment in people with acute ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Three review authors independently applied the inclusion criteria, assessed trial quality and risk of bias, extracted data, and applied GRADE criteria to the evidence.

MAIN RESULTS

Seven RCTs (1773 participants) met the inclusion criteria of the review. In this update we added one RCT of Cerebrolysin-like agent Cortexin, which contributed 272 participants. We used the same approach for risk of bias assessment that was re-evaluated for the previous update: we added consideration of the public availability of study protocols and reported outcomes to the selective outcome reporting judgement, through identification, examination, and evaluation of study protocols. For the Cerebrolysin studies, we judged the risk of bias for selective outcome reporting to be unclear across all studies; for blinding of participants and personnel to be low in three studies and unclear in the remaining four; and for blinding of outcome assessors to be low in three studies and unclear in four studies. We judged the risk of bias for generation of allocation sequence to be low in one study and unclear in the remaining six studies; for allocation concealment to be low in one study and unclear in six studies; and for incomplete outcome data to be low in three studies and high in the remaining four studies. The manufacturer of Cerebrolysin supported three multicentre studies, either totally, or by providing Cerebrolysin and placebo, randomisation codes, research grants, or statisticians. We judged two studies to be at high risk of other bias and the remaining five studies to be at unclear risk of other bias. We judged the study of Cortexin to be at low risk of bias for incomplete outcome data and at unclear risk of bias for all other domains. All-cause death: Cerebrolysin or Cortexin probably result in little to no difference in all-cause death (risk ratio (RR) 0.96, 95% confidence interval (CI) 0.65 to 1.41; 6 trials, 1689 participants; moderate-certainty evidence). None of the included studies reported on poor functional outcome, defined as death or dependence at the end of the follow-up period, early death (within two weeks of stroke onset), quality of life, or time to restoration of capacity for work. Only one study clearly reported on the cause of death: cerebral infarct (four in the Cerebrolysin and two in the placebo group), heart failure (two in the Cerebrolysin and one in the placebo group), pulmonary embolism (two in the placebo group), and pneumonia (one in the placebo group). Non-death attrition (secondary outcome): Cerebrolysin or similar peptide mixtures may result in little to no difference in non-death attrition, but the evidence is very uncertain, with a considerable level of heterogeneity (RR 0.72, 95% CI 0.38 to 1.39; 6 trials, 1689 participants; very low-certainty evidence). Serious adverse events (SAEs): Cerebrolysin probably results in little to no difference in the total number of people with SAEs (RR 1.16, 95% CI 0.81 to 1.66; 3 trials, 1335 participants; moderate-certainty evidence). This comprised fatal SAEs (RR 0.90, 95% CI 0.59 to 1.38; 3 trials, 1335 participants; moderate-certainty evidence) and an increase in the total number of people with non-fatal SAEs (RR 2.39, 95% CI 1.10 to 5.23; 3 trials, 1335 participants; moderate-certainty evidence). In the subgroup of dosing schedule 30 mL for 10 days (cumulative dose 300 mL), the increase was more prominent (RR 2.87, 95% CI 1.24 to 6.69; 2 trials, 1189 participants). Total number of people with adverse events: Cerebrolysin or similar peptide mixtures may result in little to no difference in the total number of people with adverse events (RR 1.03, 95% CI 0.92 to 1.14; 4 trials, 1607 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Moderate-certainty evidence indicates that Cerebrolysin or Cerebrolysin-like peptide mixtures derived from cattle brain probably have no beneficial effect on preventing all-cause death in acute ischaemic stroke. Moderate-certainty evidence suggests that Cerebrolysin probably has no beneficial effect on the total number of people with serious adverse events. Moderate-certainty evidence also indicates a potential increase in non-fatal serious adverse events with Cerebrolysin use.

Antihypertensive Interventions in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis Evaluating Clinical Outcomes Through an Emergency Medicine Paradigm

High blood pressure (HBP) is usually prominent after the onset of acute ischemic stroke (AIS). Although previous studies have found that about half of patients with AIS have a background of hypertension, there is no clear etiology for HBP in AIS. The literature reveals discrepancies in the relationship between HBP and clinical outcomes of AIS, pointing toward the contested effect of blood pressure (BP) reduction clinical outcomes. Thus, the potential benefits and hazards of HBP treatment were explored in the context of clinical outcomes after AIS. An electronic database and a manual search were carried out to identify all the articles related to this topic and published between 2000 and January 2023. The Review Manager software was also used to perform the meta-analysis and quality appraisal. In analyses related to patients not treated with reperfusion therapies, mortality, and dependency outcomes were categorized as short-term (<3 months) or long-term (≥3 months). Our search strategy yielded 2459 articles, of which only 15 met the inclusion criteria. The results of our meta-analysis demonstrate that in patients not treated with reperfusion therapies, BP lowering had no significant impact on either short-term or long-term mortality (risk ratio (RR): 1.18; 95% confidence interval (CI): 0.81-1.73; p = 0.39, and RR: 1.04; 95% CI: 0.77-1.40; p = 0.81, respectively) and dependency (RR: 1.12; 95% CI: 0.97-1.30; p = 0.11, and RR: 0.98; 95% CI: 0.90-1.07; p = 0.61, respectively). Furthermore, BP lowering prior to reperfusion showed no significant effect on mortality (RR: 0.7; 95% CI: 0.23-2.26; p = 0.58), but it did significantly reduce the risk of dependency (RR: 0.89; 95% CI: 0.85-0.94; p < 0.00001). When the dataset was restricted to patients who had successful reperfusion, intensive BP lowering (target systolic BP <120 mmHg) was found to increase the risk of dependency (RR: 1.23; 95% CI: 1.09-1.39; p = 0.0009). In addition, BP reduction had an insignificant effect on the risk of recurrent strokes and combined vascular events (RR: 1.00; 95% CI: 0.54-1.84; p = 1.00, and RR: 0.99; 95% CI: 0.70-1.41; p = 0.95, respectively). Lowering BP in patients not treated with reperfusion therapies is not beneficial in reducing the risk of either short or long-term mortality and dependency. However, BPR before reperfusion reduces the risk of dependency, while aggressive BPR (target systolic blood pressure (SBP) <120 mmHg) after successful reperfusion increases the risk of dependency. Therefore, we recommend BPR as early as possible for patients undergoing reperfusion therapies but suggest against aggressive BPR in patients who have undergone successful reperfusion.

The Impact of Mean Arterial Pressure and Volume Contraction in With Acute Ischemic Stroke

Background and Purpose

Hydration at the time of stroke may impact functional outcomes. We sought to investigate the relationship between blood pressure, hydration status, and stroke severity in patients with acute ischemic stroke (AIS).

Methods

We evaluated hydration status, determined by blood urea nitrogen (BUN)/creatinine ratio, in consecutive patients with AIS from a single comprehensive stroke center. Baseline mean arterial pressure (MAP) was analyzed using a linear spline with a knot at 90 mmHg. Baseline stroke severity was defined based on admission NIH Stroke Scale scores (NIHSSS) and MRI diffusion-weighted imaging.

Results

Among 108 eligible subjects, 55 (51%) presented in a volume contracted state. In adjusted models, in the total sample, for every 10 mmHg higher MAP up to 90 mmHg, NIHSSS was 2.8 points lower (p = 0.053), without further statistically significant association between MAP above 90 and NIHSSS. This relationship was entirely driven by the individuals in a volume contracted state: MAP was not associated with NIHSSS in individuals who were euvolemic. For individuals in a volume contracted state, each 10 mmHg higher MAP, up to 90 mmHg, was associated with 6.9 points lower NIHSSS (95% CI −11.1, −2.6). MAP values above 90 mmHg were not related to NIHSSS in either dehydrated or euvolemic patients.

Conclusions

Lower MAP contributes to more severe stroke in patients who are volume contracted, but not those who are euvolemic, suggesting that hydration status and blood pressure may jointly contribute to the outcome. Hydration status should be considered when setting blood pressure goals for patients with AIS.

Blood Pressure in Acute Stroke and Secondary Stroke Prevention

PURPOSE OF REVIEW

Hypertension is common in patients presenting with stroke and is independently associated with unfavorable outcomes. This article reviews current guidelines for early management of blood pressure (BP) and highlights the findings of recent investigative works.

RECENT FINDINGS

Intensive blood pressure reduction after receiving alteplase has not been shown to improve outcomes. Patients with large vessel occlusions may benefit from lower blood pressure targets post-intervention. Retrospective analyses of large intracerebral hemorrhage trials suggest that specific subgroups of patients may disproportionately benefit from or be harmed by intensive BP reduction. Robust data for management of blood pressure in subarachnoid hemorrhage patients is lacking and expert consensus continues to guide decision-making. Despite the impact of hypertension on outcomes, most prospective trials assessing efficacy of blood pressure reduction have yielded neutral or inconclusive results. Further trials are necessary to determine which patient populations are most likely to benefit from blood pressure control.

Pressor therapy in acute ischaemic stroke: an updated systematic review

Background

Low blood pressure (BP) in acute ischaemic stroke (AIS) is associated with poor functional outcome, death, or severe disability. Increasing BP might benefit patients with post-stroke hypotension including those with potentially salvageable ischaemic penumbra. This updated systematic review considers the present evidence regarding the use of vasopressors in AIS.

Methods

We searched the Cochrane Database of Systematic Reviews, MEDLINE, EMBASE and trial databases using a structured search strategy. We examined reference lists of relevant publications for additional studies examining BP elevation in AIS.

Results

We included 27 studies involving 1886 patients. Nine studies assessed increasing BP during acute reperfusion therapy (intravenous thrombolysis, mechanical thrombectomy, intra-arterial thrombolysis or combined). Eighteen studies tested BP elevation alone. Phenylephrine was the most commonly used agent to increase BP (n = 16 studies), followed by norepinephrine (n = 6), epinephrine (n = 3) and dopamine (n = 2). Because of small patient numbers and study heterogeneity, a meta-analysis was not possible. Overall, BP elevation was feasible in patients with fluctuating or worsening neurological symptoms, large vessel occlusion with labile BP, sustained post-stroke hypotension and ineligible for intravenous thrombolysis or after acute reperfusion therapy. The effects on functional outcomes were largely unknown and close monitoring is advised if such intervention is undertaken.

Conclusion

Although theoretical arguments support increasing BP to improve cerebral blood flow and sustain the ischaemic penumbra in selected AIS patients, the data are limited and results largely inconclusive. Large, randomised controlled trials are needed to identify the optimal BP target, agent, duration of treatment and effects on clinical outcomes.

Interventions for altering blood pressure in people with acute subarachnoid haemorrhage

BACKGROUND

Subarachnoid haemorrhage has an incidence of up to nine per 100,000 person-years. It carries a mortality of 30% to 45% and leaves 20% dependent in activities of daily living. The major causes of death or disability after the haemorrhage are delayed cerebral ischaemia and rebleeding. Interventions aimed at lowering blood pressure may reduce the risk of rebleeding, while the induction of hypertension may reduce the risk of delayed cerebral ischaemia. Despite the fact that medical alteration of blood pressure has been clinical practice for more than three decades, no previous systematic reviews have assessed the beneficial and harmful effects of altering blood pressure (induced hypertension or lowered blood pressure) in people with acute subarachnoid haemorrhage.

OBJECTIVES

To assess the beneficial and harmful effects of altering arterial blood pressure (induced hypertension or lowered blood pressure) in people with acute subarachnoid haemorrhage.

SEARCH METHODS

We searched the following from inception to 8 September 2020 (Chinese databases to 27 January 2019): Cochrane Stroke Group Trials register; CENTRAL; MEDLINE; Embase; five other databases, and five trial registries. We screened reference lists of review articles and relevant randomised clinical trials.

SELECTION CRITERIA

Randomised clinical trials assessing the effects of inducing hypertension or lowering blood pressure in people with acute subarachnoid haemorrhage. We included trials irrespective of publication type, status, date, and language.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. We assessed the risk of bias of all included trials to control for the risk of systematic errors. We performed trial sequential analysis to control for the risks of random errors. We also applied GRADE. Our primary outcomes were death from all causes and death or dependency. Our secondary outcomes were serious adverse events, quality of life, rebleeding, delayed cerebral ischaemia, and hydrocephalus. We assessed all outcomes closest to three months' follow-up (primary point of interest) and maximum follow-up.

MAIN RESULTS

We included three trials: two trials randomising 61 participants to induced hypertension versus no intervention, and one trial randomising 224 participants to lowered blood pressure versus placebo. All trials were at high risk of bias. The certainty of the evidence was very low for all outcomes. Induced hypertension versus control Two trials randomised participants to induced hypertension versus no intervention. Meta-analysis showed no evidence of a difference between induced hypertension versus no intervention on death from all causes (risk ratio (RR) 1.60, 95% confidence interval (CI) 0.57 to 4.42; P = 0.38; I2 = 0%; 2 trials, 61 participants; very low-certainty evidence). Trial sequential analyses showed that we had insufficient information to confirm or reject our predefined relative risk reduction of 20% or more. Meta-analysis showed no evidence of a difference between induced hypertension versus no intervention on death or dependency (RR 1.29, 95% CI 0.78 to 2.13; P = 0.33; I2 = 0%; 2 trials, 61 participants; very low-certainty evidence). Trial sequential analyses showed that we had insufficient information to confirm or reject our predefined relative risk reduction of 20% or more. Meta-analysis showed no evidence of a difference between induced hypertension and control on serious adverse events (RR 2.24, 95% CI 1.01 to 4.99; P = 0.05; I2 = 0%; 2 trials, 61 participants; very low-certainty evidence). Trial sequential analysis showed that we had insufficient information to confirm or reject our predefined relative risk reduction of 20% or more. One trial (41 participants) reported quality of life using the Stroke Specific Quality of Life Scale. The induced hypertension group had a median of 47 points (interquartile range 35 to 55) and the no-intervention group had a median of 49 points (interquartile range 35 to 55). The certainty of evidence was very low. One trial (41 participants) reported rebleeding. Fisher's exact test (P = 1.0) showed no evidence of a difference between induced hypertension and no intervention on rebleeding. The certainty of evidence was very low. Trial sequential analysis showed that we had insufficient information to confirm or reject our predefined relative risk reduction of 20% or more. One trial (20 participants) reported delayed cerebral ischaemia. Fisher's exact test (P = 1.0) showed no evidence of a difference between induced hypertension and no intervention on delayed cerebral ischaemia. The certainty of the evidence was very low. Trial sequential analysis showed that we had insufficient information to confirm or reject our predefined relative risk reduction of 20% or more. None of the trials randomising participants to induced hypertension versus no intervention reported on hydrocephalus. No subgroup analyses could be conducted for trials randomising participants to induced hypertension versus no intervention. Lowered blood pressure versus control One trial randomised 224 participants to lowered blood pressure versus placebo. The trial only reported on death from all causes. Fisher's exact test (P = 0.058) showed no evidence of a difference between lowered blood pressure versus placebo on death from all causes. The certainty of evidence was very low.

AUTHORS' CONCLUSIONS

Based on the current evidence, there is a lack of information needed to confirm or reject minimally important intervention effects on patient-important outcomes for both induced hypertension and lowered blood pressure. There is an urgent need for trials assessing the effects of altering blood pressure in people with acute subarachnoid haemorrhage. Such trials should use the SPIRIT statement for their design and the CONSORT statement for their reporting. Moreover, such trials should use methods allowing for blinded altering of blood pressure and report on patient-important outcomes such as mortality, rebleeding, delayed cerebral ischaemia, quality of life, hydrocephalus, and serious adverse events.

European Stroke Organisation (ESO) guidelines on blood pressure management in acute ischaemic stroke and intracerebral haemorrhage

The optimal blood pressure (BP) management in acute ischaemic stroke (AIS) and acute intracerebral haemorrhage (ICH) remains controversial. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions regarding BP management in acute stroke.The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. Despite several large randomised-controlled clinical trials, quality of evidence is generally low due to inconsistent results of the effect of blood pressure lowering in AIS. We recommend early and modest blood pressure control (avoiding blood pressure levels >180/105 mm Hg) in AIS patients undergoing reperfusion therapies. There is more high-quality randomised evidence for BP lowering in acute ICH, where intensive blood pressure lowering is recommended rapidly after hospital presentation with the intent to improve recovery by reducing haematoma expansion. These guidelines provide further recommendations on blood pressure thresholds and for specific patient subgroups. There is ongoing uncertainty regarding the most appropriate blood pressure management in AIS and ICH. Future randomised-controlled clinical trials are needed to inform decision making on thresholds, timing and strategy of blood pressure lowering in different acute stroke patient subgroups.

Evaluation of Systolic Blood Pressure, Use of Aspirin and Clopidogrel, and Stroke Recurrence in the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke Trial

IMPORTANCE

Elevated systolic blood pressure (SBP) after acute ischemic stroke and transient ischemic attack (TIA) is associated with future stroke risk.

OBJECTIVE

To explore the association of dual antiplatelet therapy (DAPT) with stroke recurrence among patients with acute ischemic stroke and TIA with or without elevated baseline SBP.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study performed a post hoc subgroup analysis of the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, which was a multicenter trial conducted from 2010 to 2018 at 269 sites in 10 countries in North America, Europe, Australia, and New Zealand. Patients enrolled in POINT with available blood pressure and outcome data were included in this cohort. Statistical analysis was performed from November 2020 to January 2021.

EXPOSURES

Baseline SBP less than 140 mm Hg vs greater than or equal to 140 mm Hg and the interaction term of SBP (<140 mm Hg vs ≥140 mm Hg) × treatment group (aspirin vs DAPT).

MAIN OUTCOMES AND MEASURES

The primary outcome was ischemic stroke during 90 days of follow-up. The statistical analysis fit Cox proportional hazards models adjusted for patient age, race, premorbid hypertension, diabetes, and final diagnosis of the qualifying event (stroke vs TIA).

RESULTS

Among 4781 patients in the cohort, the mean (SD) age was 64.6 (13.1) years; 2142 (44.8%) were male individuals, 3487 (72.9%) were White individuals, and 266 (5.6%) had a primary outcome of ischemic stroke during follow-up. There were 946 patients (19.8%) with baseline SBP less than 140 mm Hg and 3835 (80.2%) with SBP greater than or equal to 140 mm Hg. The interaction term (SBP × treatment) was significant (P for interaction = .03). In the subgroup of patients with SBP less than 140 mm Hg, the hazard ratio (HR) of DAPT vs aspirin alone for ischemic stroke was 0.36 (95% CI, 0.18-0.72; P = .004), whereas the HR in the subgroup with SBP greater than or equal to 140 mm Hg was 0.79 (95% CI, 0.60-1.02; P = .08). When evaluating the outcome of ischemic stroke within 7 days of randomization, the interaction term was significant (P for interaction = .02), and the HR for patients with DAPT with SBP less than 140 mm Hg was 0.19 (95% CI, 0.07-0.55; P = .002).

CONCLUSIONS AND RELEVANCE

In the POINT trial, patients with SBP less than 140 mm Hg at presentation received a greater benefit from 90 days of DAPT than those with higher baseline SBP, particularly for reduction of early ischemic stroke recurrence. Additional research is needed to replicate these findings and potentially test whether mild SBP reduction and DAPT within 12 hours of stroke onset lowers early risk of stroke recurrence.

An update on hyper-acute management of ischaemic stroke

This article aims to provide a comprehensive overview of key advances on various aspects of hyper-acute management of acute ischaemic stroke. These include neuroimaging, acute stroke unit care, management of blood pressure, reperfusion therapy including intravenous thrombolysis, mechanical thrombectomy and decompressive hemicraniectomy for malignant stroke syndrome. The challenge ahead is to ensure these evidence-based treatments are now being delivered and implemented to maximise the benefits across the population.

Magnitude of blood pressure change and clinical outcomes after thrombectomy in stroke caused by large artery occlusion

BACKGROUND

Extremes of both high and low systolic blood pressure (SBP) after mechanical thrombectomy (MT) in large artery occlusion stroke are known predictors of unfavorable outcome. However, the effect of SBP change (∆SBP) during the first 24 h on thrombectomy outcomes remains unclear. We aimed to investigate the association between ∆SBP at different time intervals and thrombectomy outcomes.

METHODS

We analyzed MT-treated patients registered in the SITS International Stroke Thrombectomy Registry from January 1, 2014 to September 3, 2019. Primary outcome was 3-month unfavorable outcome (modified Rankin scale scores 3-6). We defined ∆SBP as the mean SBP of a given time interval after MT (0-2, 2-4, 4-12, 12-24 h) minus admission SBP. Multivariable mixed logistic regression models were used to adjust for known confounders and center as random effect. Subgroup analyses were included to contrast specific subpopulations. Restricted cubic splines were used to model the associations.

RESULTS

The study population consisted of 5835 patients (mean age 70 years, 51% male, median NIHSS 16). Mean ∆SBP was -12.3, -15.7, -17.2, and -16.9 mmHg for the time intervals 0-2, 2-4, 4-12 h, and 12-24 h, respectively. Higher ∆SBP was associated with unfavorable outcome at 0-2 h (odds ratio 1.065, 95% confidence interval 1.014-1.118), 2-4 h (1.140, 1.081-1.203), 4-12 h (1.145, 1.087-1.203), and 12-24 h (1.145, 1.089-1.203), for every increase of 10 mmHg. Restricted cubic spline models suggested that increasing ∆SBP was associated with unfavorable outcome, with higher values showing increased risk of unfavorable outcome.

CONCLUSION

SBP increase after thrombectomy in large artery occlusion stroke is associated with poor functional outcome.

Blood Pressure Management Before, During, and After Endovascular Thrombectomy for Acute Ischemic Stroke

There is an absence of specific evidence or guideline recommendations on blood pressure management for large vessel occlusion stroke patients. Until randomized data are available, the periprocedural blood pressure management of patients undergoing endovascular thrombectomy can be viewed in two phases relative to the achievement of recanalization. In the hyperacute phase, prior to recanalization, hypotension should be avoided to maintain adequate penumbral perfusion. The American Heart Association guidelines should be followed for the upper end of prethrombectomy blood pressure: ≤185/110 mm Hg, unless post-tissue plasminogen activator administration when the goal is <180/105 mm Hg. After successful recanalization (thrombolysis in cerebral infarction [TICI]: 2b-3), we recommend a target of a maximum systolic blood pressure of < 160 mm Hg, while the persistently occluded patients (TICI < 2b) may require more permissive goals up to <180/105 mm Hg. Future research should focus on generating randomized data on optimal blood pressure management both before and after endovascular thrombectomy, to optimize patient outcomes for these divergent clinical scenarios.

Hypertensive Crisis in Acute Cerebrovascular Diseases Presenting at the Emergency Department: A Narrative Review

Hypertensive crisis, defined as an increase in systolic blood pressure >179 mmHg or diastolic blood pressure >109 mmHg, typically causes end-organ damage; the brain is an elective and early target, among others. The strong relationship between arterial hypertension and cerebrovascular diseases is supported by extensive evidence, with hypertension being the main modifiable risk factor for both ischemic and hemorrhagic stroke, especially when it is uncontrolled or rapidly increasing. However, despite the large amount of data on the preventive strategies and therapeutic measures that can be adopted, the management of high BP in patients with acute cerebrovascular diseases presenting at the emergency department is still an area of debate. Overall, the outcome of stroke patients with high blood pressure values basically depends on the occurrence of hypertensive emergency or hypertensive urgency, the treatment regimen adopted, the drug dosages and their timing, and certain stroke features. In this narrative review, we provide a timely update on the current treatment, debated issues, and future directions related to hypertensive crisis in patients referred to the emergency department because of an acute cerebrovascular event. This will also focus greater attention on the management of certain stroke-related, time-dependent interventions, such as intravenous thrombolysis and mechanic thrombectomy.

Hypertensive Crisis in Acute Cerebrovascular Diseases Presenting at the Emergency Department: A Narrative Review

Hypertensive crisis, defined as an increase in systolic blood pressure >179 mmHg or diastolic blood pressure >109 mmHg, typically causes end-organ damage; the brain is an elective and early target, among others. The strong relationship between arterial hypertension and cerebrovascular diseases is supported by extensive evidence, with hypertension being the main modifiable risk factor for both ischemic and hemorrhagic stroke, especially when it is uncontrolled or rapidly increasing. However, despite the large amount of data on the preventive strategies and therapeutic measures that can be adopted, the management of high BP in patients with acute cerebrovascular diseases presenting at the emergency department is still an area of debate. Overall, the outcome of stroke patients with high blood pressure values basically depends on the occurrence of hypertensive emergency or hypertensive urgency, the treatment regimen adopted, the drug dosages and their timing, and certain stroke features. In this narrative review, we provide a timely update on the current treatment, debated issues, and future directions related to hypertensive crisis in patients referred to the emergency department because of an acute cerebrovascular event. This will also focus greater attention on the management of certain stroke-related, time-dependent interventions, such as intravenous thrombolysis and mechanic thrombectomy.

Neurovascular physiology and neurocritical care

The neurological intensive care unit plays an integral role in the management of cerebrovascular disease in the acute and perioperative period. Understanding the use of intracranial pressure (ICP) monitoring and how to apply the appropriate intervention for ICP elevation to ensure adequate cerebral perfusion is the foundation of neurocritical care. Careful management of the interplay between cerebral and systemic physiology, particularly in disorders of cerebral autoregulation, is critical in preventing secondary brain injury. Finally, understanding the cerebral pathophysiology of the underlying injured brain in acute stroke, subarachnoid hemorrhage, and arterial stenosis can help to guide the optimal use of interventional endovascular procedures in these disease states.

Admission Blood Pressure in Relation to Clinical Outcomes and Successful Reperfusion After Endovascular Stroke Treatment

Supplemental Digital Content is available in the text.

Background and Purpose:

Optimal blood pressure (BP) targets before endovascular treatment (EVT) for acute ischemic stroke are unknown. We aimed to assess the relation between admission BP and clinical outcomes and successful reperfusion after EVT.

Methods:

We used data from the MR CLEAN (Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry, an observational, prospective, nationwide cohort study of patients with ischemic stroke treated with EVT in routine clinical practice in the Netherlands. Baseline systolic BP (SBP) and diastolic BP (DBP) were recorded on admission. The primary outcome was the score on the modified Rankin Scale at 90 days. Secondary outcomes included successful reperfusion (extended Thrombolysis in Cerebral Infarction score 2B-3), symptomatic intracranial hemorrhage, and 90-day mortality. Multivariable logistic and linear regression were used to assess the associations of SBP and DBP with outcomes. The relations between BPs and outcomes were tested for nonlinearity. Parameter estimates were calculated per 10 mm Hg increase or decrease in BP.

Results:

We included 3180 patients treated with EVT between March 2014 and November 2017. The relations between admission SBP and DBP with 90-day modified Rankin Scale scores and mortality were J-shaped, with inflection points around 150 and 81 mm Hg, respectively. An increase in SBP above 150 mm Hg was associated with poor functional outcome (adjusted common odds ratio, 1.09 [95% CI, 1.04–1.15]) and mortality at 90 days (adjusted odds ratio, 1.09 [95% CI, 1.03–1.16]). Following linear relationships, higher SBP was associated with a lower probability of successful reperfusion (adjusted odds ratio, 0.97 [95% CI, 0.94–0.99]) and with the occurrence of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.06 [95% CI, 0.99–1.13]). Results for DBP were largely similar.

Conclusions:

In patients with acute ischemic stroke treated with EVT, higher admission BP is associated with lower probability of successful reperfusion and with poor clinical outcomes. Further research is needed to investigate whether these patients benefit from BP reduction before EVT.

Relationship between blood pressure and outcome changes over time in acute ischemic stroke

OBJECTIVE

To evaluate whether the relationship between systolic blood pressure (SBP) and stroke outcome varies during the acute stage of ischemic stroke as a function of the elapsed time after stroke onset.

METHODS

Patients who were hospitalized due to ischemic stroke within 6 hours of onset were retrospectively analyzed. SBP data were collected at 8 time points (1, 2, 4, 8, 16, 24, 48, and 72 hours after onset). The primary functional outcome measure was a poor outcome, defined as a modified Rankin Scale score of >2 at 3 months after stroke. Linear and quadratic models were constructed at each time point to assess relationships between SBP and outcome.

RESULTS

Of the 2,546 patients, 728 (28.6%) had a poor outcome. SBP, as either a linear or quadratic term, had a significant effect on functional outcome, except at 4 hours after onset. For the initial 2 hours after onset, SBP had nonlinear U-shaped relationships with functional outcome, and patients with SBP of approximately 165 mm Hg were the least likely to have a poor outcome. Quadratic models exhibited a significantly better model fit. For 8-24 hours postonset, SBP exhibited linear relationships with functional outcome. For 48-72 hours postonset, SBP exhibited a J-shaped relationship with functional outcome, and the predicted probability of poor outcome was the lowest in patients with SBP of approximately 125 mm Hg. These relationships were relatively consistent across various sensitivity analyses.

CONCLUSION

This study revealed that the relationship between SBP and functional outcome may depend on elapsed time from stroke onset.

Blood pressure reduction and outcome after endovascular therapy: a secondary analysis of the BEST study

BACKGROUND

Elevated systolic blood pressure (SBP) in the acute phase after endovascular therapy (EVT) is associated with worse outcome. However, the association between systolic blood pressure reduction (SBPr) and the outcome of EVT is not well understood.

OBJECTIVE

To determine the association between SBPr and clinical outcomes after EVT in a prospective multicenter cohort.

METHODS

A post hoc analysis of the Blood Pressure after Endovascular Stroke Therapy (BEST) prospective observational cohort study was carried out. SBPr was defined as the absolute difference between admission SBP and mean SBP in the first 24 hours after EVT. Logistic regression was used to assess the association between SBPr and poor functional outcome (modified Rankin Scale score 3-6) at 90 days.

RESULTS

A total of 259/433 (58.5%) patients had poor outcome. SBPr was higher in the poor outcome group than in the good outcome group (26.6±27.4 vs 19.0±22.3 mm Hg; p<0.001). However, in adjusted models, SBPr was not independently associated with poor outcome (OR=1.00 per 1 mm Hg increase, 95% CI 0.99 to 1.01) or death (OR=0.9 per 1 mm Hg increase; 95% CI 0.98 to 1.00). No association remained when SBPr was divided into tertiles. Subgroup analyses based on history of hypertension, revascularization status, and antihypertensive treatment yielded similar results.

CONCLUSION

The reduction in baseline SBP following EVT was not associated with poor functional outcomes. Most of the cohort (88%) achieved successful recanalization, and therefore, these results mainly apply to patients with successful recanalization.

Cerebrolysin for acute ischaemic stroke

BACKGROUND

Cerebrolysin is a mixture of low-molecular-weight peptides and amino acids derived from porcine brain that has potential neuroprotective properties. It is widely used in the treatment of acute ischaemic stroke in Russia, Eastern Europe, China, and other Asian and post-Soviet countries. This is an update of a review first published in 2010 and last updated in 2017.

OBJECTIVES

To assess the benefits and harms of Cerebrolysin for treating acute ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE, Embase, Web of Science Core Collection, with Science Citation Index, LILACS, OpenGrey, and a number of Russian databases in October 2019. We also searched reference lists, ongoing trials registers, and conference proceedings.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing Cerebrolysin, started within 48 hours of stroke onset and continued for any length of time, with placebo or no treatment in people with acute ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria, assessed trial quality and risk of bias, extracted data, and applied GRADE criteria to the evidence.

MAIN RESULTS

Seven RCTs (1601 participants) met the inclusion criteria of the review. In this update we re-evaluated risk of bias through identification, examination, and evaluation of study protocols and judged it to be low, unclear, or high across studies: unclear for all domains in one study, and unclear for selective outcome reporting across all studies; low for blinding of participants and personnel in four studies and unclear in the remaining three; low for blinding of outcome assessors in three studies and unclear in four studies. We judged risk of bias to be low in two studies and unclear in the remaining five studies for generation of allocation sequence; low in one study and unclear in six studies for allocation concealment; and low in one study, unclear in one study, and high in the remaining five studies for incomplete outcome data. The manufacturer of Cerebrolysin supported four multicentre studies, either totally, or by providing Cerebrolysin and placebo, randomisation codes, research grants, or statisticians. We judged three studies to be at high risk of other bias and the remaining four studies to be at unclear risk of other bias. All-cause death: we extracted data from six trials (1517 participants). Cerebrolysin probably results in little to no difference in all-cause death: risk ratio (RR) 0.90, 95% confidence interval (CI) 0.61 to 1.32 (6 trials, 1517 participants, moderate-quality evidence). None of the included trials reported on poor functional outcome defined as death or dependence at the end of the follow-up period or early death (within two weeks of stroke onset), or time to restoration of capacity for work and quality of life. Only one trial clearly reported on the cause of death: cerebral infarct (four in the Cerebrolysin and two in the placebo group), heart failure (two in the Cerebrolysin and one in the placebo group), pulmonary embolism (two in the placebo group), and pneumonia (one in the placebo group). Serious adverse events (SAEs): Cerebrolysin probably results in little to no difference in the total number of people with SAEs (RR 1.15, 95% CI 0.81 to 1.65, 4 RCTs, 1435 participants, moderate-quality evidence). This comprised fatal SAEs (RR 0.90, 95% CI 0.59 to 1.38) and an increase in the total number of people with non-fatal SAEs (RR 2.15, 95% CI 1.01 to 4.55, P = 0.047, 4 trials, 1435 participants, moderate-quality evidence). In the subgroup of dosing schedule 30 mL for 10 days (cumulative dose 300 mL), the increase was more prominent: RR 2.86, 95% CI 1.23 to 6.66, P = 0.01 (2 trials, 1189 participants). Total number of people with adverse events: four trials reported on this outcome. Cerebrolysin may result in little to no difference in the total number of people with adverse events: RR 0.97, 95% CI 0.85 to 1.10, P = 0.90, 4 trials, 1435 participants, low-quality evidence. Non-death attrition: evidence from six trials involving 1517 participants suggests that Cerebrolysin results in little to no difference in non-death attrition, with 96 out of 764 Cerebrolysin-treated participants and 117 out of 753 placebo-treated participants being lost to follow-up for reasons other than death (very low-quality evidence).

AUTHORS' CONCLUSIONS

Moderate-quality evidence indicates that Cerebrolysin probably has little or no beneficial effect on preventing all-cause death in acute ischaemic stroke, or on the total number of people with serious adverse events. Moderate-quality evidence also indicates a potential increase in non-fatal serious adverse events with Cerebrolysin use.

A calcium channel or angiotensin converting enzyme inhibitor/angiotensin receptor blocker regime to reduced blood pressure variability in acute ischaemic stroke (CAARBS): A feasibility trial

BACKGROUND

Trials of lowering blood pressure in patients with acute ischaemic stroke not undergoing thrombolysis have not demonstrated improved outcomes with intervention. Rather than absolute levels, it may be that blood pressure variability is important. However, there are no prospective randomised trials investigating the benefit of reducing blood pressure variability in this patient group.

AIMS

The primary aim of this trial was to determine the feasibility of recruitment to a randomised trial investigating the effect of different antihypertensive medications on blood pressure variability.

METHODS

CAARBS was a multi-centre, open-label, randomised parallel group controlled feasibility trial. Adults with a first mild-moderate ischaemic stroke or transient ischaemic attack, requiring antihypertensive therapy for secondary prevention, were randomised to a calcium channel blocker or angiotensin-converting enzyme inhibitor/angiotensin receptor blocker. Blood pressure and variability were measured at baseline, three weeks, and three months. Compliance with measurements and treatment was monitored.

RESULTS

Fourteen patients were recruited to the trial (0.6% of those screened), nine of whom completed follow-up. The majority of patients screened (98.1%) were ineligible. Compliance with the intervention was good, as were measurement completion rates (88.9% or higher in all cases except ambulatory measurements). No major adverse events were recorded.

CONCLUSIONS

Recruitment to the trial was difficult due to patient ineligibility, suggesting that the current protocol is unlikely to be successful if scaled for a definitive trial. However, the intervention was safe, and compliance was good, suggesting a future trial with modified eligibility criteria could be successful.

TRIAL REGISTRATION

ISRCTN10853487.

[Hypertensive Crisis in the Elderly Patients]

A hypertensive crisis is a sudden increase in blood pressure (BP) to an individually high level associated with clinical symptoms and target organ damage, in which BP must be reduced immediately. Since 2018 in Europe and since 2020 in Russia, an uncomplicated hypertensive crisis is recommended to be considered as a part of malignant (uncontrolled) arterial hypertension. The clinical picture of increased BP in elderly patients is characterized by nonspecific symptoms even in target organ damage. Management of this group of patients requires a physician to know the patient's comorbidities and the drugs taken on a regular basis to minimize development of side effects of the administered drugs and their undesirable interaction with the chronic therapy.

Role of 24-Hr Blood Pressure Variability as a Target Therapeutic Risk Factor for Poor Functional Outcome of Acute Ischemic Stroke

Background and Purpose:

The present study aims to evaluate the role of blood pressure variability (BPV) as a target therapeutic risk factor for poor outcome of ischemic stroke by finding the association between the two and by finding the population attributable risk (PAR) of BPV compared to other baseline outcome predictors.

Methods:

A prospective observational study was carried out at GMCH, Nagpur, India from January to June 2019 in 75 patients diagnosed with acute ischemic stroke. BP was recorded hourly for the first 24 hours of admission and base line factors were collected along with measurement of stroke severity. BPV was measured by index of average real-time variability (ARV) while discharge outcome was measured by Barthel Index.

Results:

36.5% of patients had poor outcome at discharge. A significant association was found between 24-hr ARV of systolic BP and poor outcome (P = 0.002, 95% CI = 2.22-23.5). Five factors were found to be independent outcome predictors on multiple logistic regression (OR, 95% CI): age (1.07, 1.03–1.10), NIHSS score (1.12, 1.04–1.27), on admission SBP (5.12, 4.01–16.23), on admission RBS (2.23, 1.92–6.49) and 24 Hr ARV-SBP (9.65, 3.02–20.1). The PAR of 24 hr ARV-SBP was 23.6%, second only to NIHSS score (26.4%).

Conclusions:

Reduction in BP variability might have a beneficial impact on the outcome of patients with acute ischemic stroke. There is further scope to explore optimum therapeutic strategies to minimize BPV in the management of acute ischemic stroke.

Early Manipulation of Arterial Blood Pressure in Acute Ischemic Stroke (MAPAS): Results of a Randomized Controlled Trial

INTRODUCTION

There is uncertainty over the optimal level of systolic blood pressure (SBP) in the setting of acute ischemic stroke (AIS). The aim of this study was to determine the efficacy of the early manipulation of SBP in non-thrombolised patients. The key hypothesis under investigation was that clinical outcomes vary across ranges of SBP in AIS.

METHODS

218 patients were randomized within 12 h of AIS to maintain the SBP during 24 h within three ranges: Group 1 140-160 mmHg, Group 2 161-180 mmHg or Group 3 181-200 mmHg. Vasoactive drugs and fluids were used to achieve these targets. Good outcome was defined as a modified Rankin score 0-2 at 90-days.

RESULTS

The median SBP in the three groups in 24 h was: 153 mmHg, 163 mmHg, and 178 mmHg, respectively, P < 0.0001. Good clinical outcome did not differ among the different groups (51% vs 52% vs 39%, P = 0.27). Symptomatic intracranial hemorrhage (SICH) was more frequent in the higher SBP range (1% vs 2.7% vs 9.1%, P = 0.048) with similar mortality rates. No patient had acute neurological deterioration related to the SBP reduction in the first 24 h. In our logistic regression analysis, the odds of having good clinical outcome was higher in Group 2 (OR 2.83) after adjusting for important confounders. Regardless of the assigned group, the probability of good outcome was 47% in patients who were manipulated to increase the BP, 42% to decrease and 62% in non-manipulated (P = 0.1). Adverse effects were limited to Group 2 (4%) and Group 3 (7.6%) and were associated with the use of norepinephrine (P = 0.05).

CONCLUSIONS

Good outcome in 90 days was not significantly different among the 3 blood pressure ranges. After logistic regression analysis, the odds of having good outcome was greater in Group 2 (SBP 161-180 mmHg). SICH occurred more frequently in Group 3 (181-200 mmHg).

Effect of blood pressure parameters on functional independence in patients with acute ischemic stroke in the first 6 hours after endovascular thrombectomy

BACKGROUND AND PURPOSE

Studies have suggested that blood pressure (BP) levels after endovascular thrombectomy (EVT) are correlated with clinical outcomes. The aim of our study was to investigate the effect of BP in different time intervals within the first 24 hours after EVT on functional outcomes.

METHODS

Data of patients who received EVT for acute ischemic stroke at two institutions were reviewed. After EVT, hourly BP data were collected and divided into four time intervals: 1-6 hours, 7-12 hours, 13-18 hours, and 19-24 hours. The mean, maximum, and standard deviation (SD) of BP were calculated and compared with the outcome of interest in patients with successful recanalization. The outcome of interest was functional independence, which was defined as a 3-month modified Rankin Scale score of ≤2.

RESULTS

Of 224 patients with stroke who received EVT, 166 (74.1%) (mean age 70.2±13.1 years; 49.4% men) achieved successful recanalization and 82 (49.4%) exhibited functional independence. After adjustment for possible confounders, lower mean, maximum, and SD values of systolic and diastolic BP observed in the first 6 hours after EVT were independently associated with functional independence. Furthermore, the area under the receiver operating characteristic curve values observed for BP parameters for outcome prediction in the first 6 hours were the highest across the 24-hour period following EVT.

CONCLUSION

In patients with stroke who achieved successful recanalization, the first 6 hours after EVT was the key period influencing the correlation between BP and functional outcome.

Blood Pressure Variability and Neurologic Outcome After Endovascular Thrombectomy: A Secondary Analysis of the BEST Study

Background and Purpose- Although higher blood pressure variability (BPV) is associated with worse functional outcome after stroke, this association is not as well established in large vessel occlusion strokes treated with endovascular treatment (EVT). Methods- In this post hoc analysis of BEST (Blood Pressure after Endovascular Therapy for Ischemic Stroke), a prospective, multicenter cohort study of anterior circulation acute ischemic stroke patients undergoing EVT, we determined the association of BPV with poor outcome or death (90-day modified Rankin Scale, 3-6). We calculated BPV during the first 24 hours after EVT for systolic and diastolic BP using 5 methodologies, then divided BPV into tertiles and compared the highest to lowest tertile using logistic regression. Results- Of the 443 patients included in our analysis, 259 (58.5%) had a poor outcome, and 79 (17.8%) died. All measures of BPV were significantly higher in patients with poor outcome or death, but the difference was more pronounced for systolic than diastolic BPV. In the logistic regression, the highest tertile of systolic BPV consistently predicted poor outcome (odds ratio, 1.8-3.5, all P<0.05). The rate of death within 90 days was 10.1% in the tertile with the lowest systolic BPV versus 25.2% in the tertile with the highest BPV (P<0.001). Conclusions- In EVT-treated stroke patients, higher BPV in the first 24 hours is associated with worse 90-day outcome. This association was more robust for systolic BPV. The mechanism by which BPV may exert a negative influence on neurological outcome remains unknown, but the consistency of this association warrants further investigation and potentially intervention.

Emergency management of stroke in the era of mechanical thrombectomy

Emergency management of stroke has been directed at the delivery of recombinant tissue plasminogen activator (tPA) in a timely fashion. Because of the many limitations attached to the delivery of tPA and the perceived benefits accrued to tPA, its use has been limited. Mechanical thrombectomy, a far superior therapy for the largest and most disabling strokes, large vessel occlusions (LVOs), has changed the way acute strokes are managed. Aside from the rush to deliver tPA, there is now a need to identify LVO and refer those patients with LVO to physicians and facilities capable of delivering urgent thrombectomy. Other parts of emergency department management of stroke are directed at identifying and mitigating risk factors for future strokes and at preventing further damage from occurring. We review here the most recent literature supporting these advances in stroke care and present a framework for understanding the role that emergency physicians play in acute stroke care.

Is spontaneous normalization of systolic blood pressure within 24 hours after ischemic stroke onset related with favorable outcomes?

Background

In acute ischemic stroke, blood pressure (BP) tends to rise initially and fall to a baseline level within 24–48 hours. Previous studies reported several different effects of BPs during acute ischemic stroke on clinical outcomes, which was partly due to the different time intervals from stroke onset to BP measurement.

Methods

All patients with acute ischemic stroke (onset ≤3 hours) who lived independently before the stroke, were consecutively enrolled for a 62-month period. BPs at 0, 12, and 24 hours after admission were collected. A favorable outcome was defined as a modified Rankin Scale (mRS) score 0–2 at discharge. For different standards of BP management, patients were grouped and analyzed according to intravenous (IV) tissue plasminogen activator (tPA) treatment and favorable outcome.

Results

Among the 446 enrolled patients, 227 patients underwent IV tPA treatment and 216 had mRS score 0–2 at discharge. Patients with favorable outcomes had lower initial NIH Stroke Scale (NIHSS) scores, less frequent progressive neurological deficits, and lower systolic BP (SBP) 12 and 24 hours after admission than patients with unfavorable outcomes, regardless of whether they underwent tPA treatment or not (p <0.05). The BP decreased over a period of 24 hours after admission. In logistic regression analysis, the independent variables associated with favorable outcome were the initial NIHSS score, a progressive neurological deficit, a previous stroke, and the SBP 24 hours after admission in the patients who underwent tPA treatment and the initial NIHSS score and a progressive neurological deficit in the patients who did not undergo tPA treatment (p <0.05).

Conclusions

The SBPs at 12 and 24 hours after admission were lower in acute stroke patients with favorable outcomes than in the other patients, regardless of whether the patients underwent tPA therapy and the SBP at 24 hours was an independent predictor of favorable outcomes among the patients who underwent tPA treatment.

Therapeutic-induced hypertension in patients with noncardioembolic acute stroke

OBJECTIVE

To evaluate the safety and efficacy of induced hypertension in patients with acute ischemic stroke.

METHODS

In this multicenter randomized clinical trial, patients with acute noncardioembolic ischemic stroke within 24 hours of onset who were ineligible for revascularization therapy and those with progressive stroke during hospitalization were randomly assigned (1:1) to the control and intervention groups. In the intervention group, phenylephrine was administered intravenously to increase systolic blood pressure (SBP) up to 200 mm Hg. The primary efficacy endpoint was early neurologic improvement (reduction in NIH Stroke Scale [NIHSS] score of ≥2 points during the first 7 days). The secondary efficacy endpoint was a modified Rankin Scale score of 0 to 2 at 90 days. Safety outcomes included symptomatic intracranial hemorrhage/edema, myocardial infarction, and death.

RESULTS

In the modified intention-to-treat analyses, 76 and 77 patients were included in the intervention and control groups, respectively. After adjustment for age and initial stroke severity, induced hypertension increased the occurrence of the primary (odds ratio 2.49, 95% confidence interval [CI] 1.25-4.96, p = 0.010) and secondary (odds ratio 2.97, 95% CI 1.32-6.68, p = 0.009) efficacy endpoints. Sixty-seven (88.2%) patients of the intervention group exhibited improvements in NIHSS scores of ≥2 points during induced hypertension (mean SBP 179·7 ± 19.1 mm Hg). Safety outcomes did not significantly differ between groups.

CONCLUSION

Among patients with noncardioembolic stroke who were ineligible for revascularization therapy and those with progressive stroke, phenylephrine-induced hypertension was safe and resulted in early neurologic improvement and long-term functional independence.

CLINICALTRIALSGOV IDENTIFIER

NCT01600235.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with acute ischemic stroke, therapeutic-induced hypertension increases the probability of early neurologic improvement.

Effect of Nebivolol and Olmesartan on 24-Hour Brachial and Aortic Blood Pressure in the Acute Stage of Ischemic Stroke

Background

Elevated blood pressure (BP) in the acute phase of ischemic stroke is associated with heightened risk of early disability and death. However, whether BP-lowering in this setting is beneficial and the exact levels at which BP should be targeted remain unclear. This study aimed to evaluate the effect of nebivolol, olmesartan, and no-treatment on 24-hour BP in patients with hypertension during the acute poststroke period.

Methods

In a single-blind fashion, 60 patients with acute ischemic stroke and clinic systolic BP (SBP) 160-220 mmHg were randomized to nebivolol (5 mg/day), olmesartan (20 mg/day), or no-treatment between Day 4 and Day 7 of stroke onset. BP-lowering efficacy was assessed through 24-hour BP monitoring using the Mobil-O-Graph device (IEM, Germany).

Results

Between baseline and Day 7, significant reductions in 24-hour brachial SBP were noted with nebivolol and olmesartan, but not with no-treatment. Change from baseline (CFB) in 24-hour brachial SBP was not different between nebivolol and olmesartan groups (between-group difference: -3.4 mmHg; 95% confidence interval (CI): -11.2, 4.3), whereas nebivolol was superior to no-treatment in lowering 24-hour brachial SBP (between-group difference: -7.8 mmHg; 95% CI: -7.8 mmHg; 95% CI: -15.6, -0.1). Similarly, nebivolol and olmesartan equally lowered 24-hour aortic SBP (between-group difference: -1.9 mmHg; 95% CI: -10.1, 6.2). Nebivolol and olmesartan provoked similar reductions in 24-hour heart rate-adjusted augmentation index and pulse wave velocity.

Conclusion

This study suggests that during the acute phase of ischemic stroke, nebivolol is equally effective with olmesartan in improving 24-hour aortic pressure and arterial stiffness indices. ClinicalTrials.gov identifier number: NCT03655964.

Integrative analysis of transcriptome-wide association study and gene expression profiling identifies candidate genes associated with stroke

Background

Stroke is a major public health burden worldwide. Although genetic variation is known to play a role in the pathogenesis of stroke, the specific pathogenic mechanisms are still unclear. Transcriptome-wide association studies (TWAS) is a powerful approach to prioritize candidate risk genes underlying complex traits. However, this approach has not been applied in stroke.

Methods

We conducted an integrative analysis of TWAS using data from the MEGASTROKE Consortium and gene expression profiling to identify candidate genes for the pathogenesis of stroke. Gene ontology (GO) enrichment analysis was also conducted to detect functional gene sets.

Results

The TWAS identified 515 transcriptome-wide significant tissue-specific genes, among which SLC25A44 (P = 5.46E−10) and LRCH1 (P = 1.54E−6) were significant by Bonferroni test for stroke. After validation with gene expression profiling, 19 unique genes were recognized. GO enrichment analysis identified eight significant GO functional gene sets, including regulation of cell shape (P = 0.0059), face morphogenesis (P = 0.0247), and positive regulation of ATPase activity (P = 0.0256).

Conclusions

Our study identified multiple stroke-associated genes and gene sets, and this analysis provided novel insights into the genetic mechanisms underlying stroke.

Lowering blood pressure after acute intracerebral haemorrhage: protocol for a systematic review and meta-analysis using individual patient data from randomised controlled trials participating in the Blood Pressure in Acute Stroke Collaboration (BASC)

INTRODUCTION

Conflicting results from multiple randomised trials indicate that the methods and effects of blood pressure (BP) reduction after acute intracerebral haemorrhage (ICH) are complex. The Blood pressure in Acute Stroke Collaboration is an international collaboration, which aims to determine the optimal management of BP after acute stroke including ICH.

METHODS AND ANALYSIS

A systematic review will be undertaken according to the Preferred Reporting Items for Systematic review and Meta-Analysis of Individual Participant Data (IPD) guideline. A search of Cochrane Central Register of Controlled Trials, EMBASE and MEDLINE from inception will be conducted to identify randomised controlled trials of BP management in adults with acute spontaneous (non-traumatic) ICH enrolled within the first 7 days of symptom onset. Authors of studies that meet the inclusion criteria will be invited to share their IPD. The primary outcome will be functional outcome according to the modified Rankin Scale. Safety outcomes will be early neurological deterioration, symptomatic hypotension and serious adverse events. Secondary outcomes will include death and neuroradiological and haemodynamic variables. Meta-analyses of pooled IPD using the intention-to-treat dataset of included trials, including subgroup analyses to assess modification of the effects of BP lowering by time to treatment, treatment strategy and patient's demographic, clinical and prestroke neuroradiological characteristics.

ETHICS AND DISSEMINATION

No new patient data will be collected nor is there any deviation from the original purposes of each study where ethical approvals were granted; therefore, further ethical approval is not required. Results will be reported in international peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42019141136.

Multicentre Randomised trial of Acute Stroke treatment in the Ambulance with a nitroglycerin Patch (MR ASAP): study protocol for a randomised controlled trial

BACKGROUND

Some studies have suggested that transdermal administration of glyceryl trinitrate (GTN; nitroglycerin) in the first few hours after symptom onset increases the chance of a favourable outcome after ischaemic stroke or intracerebral haemorrhage, possibly through an increase in intracranial collateral blood flow and a reduction in blood pressure. The Multicentre Randomised trial of Acute Stroke treatment in the Ambulance with a nitroglycerin Patch (MR ASAP) aims to assess the effect of transdermal GTN, started within 3 h after stroke onset in the prehospital setting, on functional outcome at 90 days in patients with acute ischaemic stroke or intracerebral haemorrhage.

METHODS

MR ASAP is a phase III, multicentre, randomised, open-label clinical trial with a blinded outcome assessment. A total of 1400 adult patients with suspected stroke and a systolic blood pressure ≥ 140 mmHg will be randomised to transdermal GTN (5 mg/day), administered as a transdermal patch by paramedics in the prehospital setting within 3 h of stroke onset and continued for 24 h or to standard care. The primary outcome is the score on the modified Rankin Scale (mRS) at 90 days, analysed with ordinal logistic regression. Secondary outcomes include blood pressure and collateral circulation at hospital admission, neurological deficit measured with the National Institutes of Health Stroke Scale at 24 h, and mortality and poor outcome (mRS score 3 to 6) at 90 days. This trial will be conducted in the Netherlands and will use a deferred consent procedure. The trial is part of the Collaboration for New Treatments of Acute Stroke (CONTRAST) programme.

DISCUSSION

MR ASAP will assess whether very early administration of GTN improves outcome after stroke in a setting where rates of intravenous thrombolysis and endovascular treatment for acute ischaemic stroke are high. The deferred consent procedure facilitates prompt GTN treatment and will prevent delay to revascularisation therapies. If early transdermal GTN treatment proves to be effective, this low-cost treatment can be readily implemented into daily clinical practice.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN99503308 . Registered on 2 January 2018.

It is safe to use transdermal glyceryl trinitrate to lower blood pressure in patients with acute ischaemic stroke with carotid stenosis

Background

There is concern that blood pressure (BP) lowering in acute stroke may compromise cerebral perfusion and worsen outcome in the presence of carotid stenosis. We assessed the effect of glyceryl trinitrate (GTN) in patients with carotid stenosis using data from the Efficacy of Nitric Oxide in Stroke (ENOS) Trial.

Methods

ENOS randomised 4011 patients with acute stroke and raised systolic BP (140-220 mm Hg) to transdermal GTN or no GTN within 48 hours of onset. Those on prestroke antihypertensives were also randomised to stop or continue their medication for 7 days. The primary outcome was the modified Rankin Scale (mRS) at day 90. Ipsilateral carotid stenosis was split: <30%; 30-<50%; 50-<70%; ≥70%. Data are ORs with 95% CIs adjusted for baseline prognostic factors.

Results

2023 (60.5%) ischaemic stroke participants had carotid imaging. As compared with <30%, ≥70% ipsilateral stenosis was associated with an unfavourable shift in mRS (worse outcome) at 90 days (OR 1.88, 95% CI 1.44 to 2.44, p<0.001). Those with ≥70% stenosis who received GTN versus no GTN had a favourable shift in mRS (OR 0.56, 95% CI 0.34 to 0.93, p=0.024). In those with 50-<70% stenosis, continuing versus stopping prestroke antihypertensives was associated with worse disability, mood, quality of life and cognition at 90 days. Clinical outcomes did not differ across bilateral stenosis groups.

Conclusions

Following ischaemic stroke, severe ipsilateral carotid stenosis is associated with worse functional outcome at 90 days. GTN appears safe in ipsilateral or bilateral carotid stenosis, and might improve outcome in severe ipsilateral carotid stenosis.

Management of Blood Pressure During and After Recanalization Therapy for Acute Ischemic Stroke

Ischemic stroke is a common neurologic condition and can lead to significant long term disability and death. Observational studies have demonstrated worse outcomes in patients presenting with the extremes of blood pressure as well as with hemodynamic variability. Despite these associations, optimal hemodynamic management in the immediate period of ischemic stroke remains an unresolved issue, particularly in the modern era of revascularization therapies. While guidelines exist for BP thresholds during and after thrombolytic therapy, there is substantially less data to guide management during mechanical thrombectomy. Ideal blood pressure targets after attempted recanalization depend both on the degree of reperfusion achieved as well as the extent of infarction present. Following complete reperfusion, lower blood pressure targets may be warranted to prevent reperfusion injury and promote penumbra recovery however prospective clinical trials addressing this issue are warranted.

Randomised controlled trial of a Calcium Channel or Angiotensin Converting Enzyme Inhibitor/Angiotensin Receptor Blocker Regime to Reduce Blood Pressure Variability following Ischaemic Stroke (CAARBS): a protocol for a feasibility study

INTRODUCTION

Raised blood pressure (BP) is common after stroke and is associated with a poor prognosis, yet trials of BP lowering in the immediate poststroke period have not demonstrated a benefit. One possible explanation for this may be that BP variability (BPV) rather than absolute levels predicts outcome, as BPV is increased after stroke and is associated with poor outcomes. Furthermore, there is evidence of distinct antihypertensive class effects on BPV despite similar BP-lowering effects. However, whether BPV in the immediate poststroke period is a therapeutic target has not been prospectively investigated.The objectives of this trial are to assess the feasibility and safety of recruiting patients following an acute ischaemic stroke or transient ischaemic attack (TIA) to an interventional randomised controlled trial comparing the effects of two different antihypertensive drug classes on BPV. Secondary exploratory objectives are to assess if different therapeutic strategies have diverse effects on levels of BPV and if this has an impact on outcomes.

METHODS

150 adult patients with first-ever ischaemic stroke or TIA who require antihypertensive therapy for secondary prevention will be recruited within 7 days of the event from stroke services across three sites. After baseline assessments they will be randomly assigned to treatment with a calcium channel blocker or ACE inhibitor/angiotensin receptor blocker-based regimen and followed up for a period of three months.

ETHICS AND DISSEMINATION

Ethical and regulatory approvals have been granted. Dissemination is planned via publication in peer-reviewed medical journals and presentation at relevant conferences.

TRIAL REGISTRATION NUMBER

ISRCTN10853487.

Efficacy of Antihypertensive Therapy in the Acute Stage of Cerebral Infarction - A Prospective, Randomized Control Trial

Background

This study investigated whether patients in the acute stage of cerebral infarction (ACI) might benefit from single-drug antihypertensive therapy (AT) without the use of preset target levels.

Methods

A total of 320 ACI patients were randomly divided into an AT group and a control group (group C) (160 patients in each group). The AT group received single antihypertensive drug treatment after the first 48 hours of onset with 5 mg of amlodipine besylate or 150 mg of irbesartan once a day. The primary end-point event was mortality on the 14^th day and in the 6^th month after onset, significant dependent-survival status (SDS, Barthel Index ≤ 60), mortality/disability ratio (modified Rankin Scale ≥ 3), and recurrence rate of cardio-cerebral vascular events (RR-CVE).

Results

The National Institutes of Health Stroke Scale (NIHSS) score was 8.39 ± 3.21 vs. 8.16 ± 3.27 in the AT and C groups on entry to the study. On day 14, there were no significant differences in mortality (2.5% vs. 3.1%, p = 0.9994), SDS (50.0% vs. 49.0%, p = 0.864), and mortality/disability ratio (61.3% vs. 66.3%, p = 0.352) between the two groups, however the RR-CVE in the AT group was lower than in group C (4.4% vs. 11.9%, p = 0.014). In month 6, there were no significant difference in mortality rate between the two groups (3.1% vs. 3.8%, p = 0.767), however the SDS (23.4% vs. 34.4%, p = 0.033), mortality/disability ratio (32.1% vs. 45.0%, p = 0.018), and RR-CVE in group AT were lower than in group C (10.7% vs. 19.4%, p = 0.030).

Conclusions

Appropriate AT for patients with ACI does not worsen the disease condition and may improve the prognosis for the patients with moderate or mild stroke severity.

Antihypertensive therapy in acute ischemic stroke: where do we stand?

Despite the proven benefits of strict blood pressure (BP) control on primary and secondary prevention of stroke, management of acute hypertensive response in the early post-stroke period is surrounded by substantial controversy. Observational studies showed that raised BP on ischemic stroke onset is prognostically associated with excess risk for early adverse events and mortality. By contrast, randomized controlled trials and recent meta-analyses showed that although antihypertensive therapy effectively controls elevated BP in the acute stage of ischemic stroke, this BP-lowering effect is not translated into improvement in the risk of death or dependency. On this basis, acute and aggressive BP responses within 24 h of stroke onset should be avoided and antihypertensive therapy is recommended only for patients presenting with acute ischemic stroke and BP > 220/120 mmHg or those with BP > 185/110 mmHg who are eligible for therapy with intravenous tissue plasminogen activator. By contrast, recent clinical trials showed that intensive BP lowering to levels < 140 mmHg for systolic BP is safe and lowers the risk of hematoma expansion in patients with acute intra-cerebral hemorrhage and this BP target is recommended by current international guidelines. Herein, we provide an overview of randomized trials and recent meta-analyses on the management of hypertension during the acute stage of ischemic stroke. We discuss several areas of uncertainty and conclude with perspectives for future research.

Acute Treatment of Stroke (Except Thrombectomy)

PURPOSE OF REVIEW

The management of patients with acute stroke has been revolutionized in recent years with the advent of new effective treatments. In this rapidly evolving field, we provide an update on the management of acute stroke excluding thrombectomy, looking to recent, ongoing, and future trials.

RECENT FINDINGS

Large definitive trials have provided insight into acute stroke care including broadening the therapeutic window for thrombolysis, alternatives to standard dose alteplase, the use of dual antiplatelet therapy early after minor ischemic stroke, and treating elevated blood pressure in intracerebral hemorrhage. Further ongoing and future trials are eagerly awaited in this ever-expanding area. Although definitive trials have led to improvements in acute stroke care, there remains a need for further research to improve our understanding of pathophysiological mechanisms underlying different stroke types with the potential for treatments to be tailored to the individual.

Management of hypertensive crises in the elderly

Hypertensive crises are elevations of blood pressure higher than 180/120 mmHg. These can be urgent or emergent, depending on the presence of end organ damage. The clinical presentation of hypertensive crises is quite variable in elderly patients, and clinicians must be suspicious of non-specific symptoms. Managing hypertensive crises in elderly patients needs meticulous knowledge of the pathophysiological changes in them, pharmacological options, pharmacokinetics of the medications used, their side effects, and their interactions with other medications. Clevidipine, nicardipine, labetalol, esmolol, and fenoldopam are among the preferred choices in the elderly due to their efficacy and tolerability. Nitroprusside, hydralazine, and nifedipine should be avoided, unless there are no other options available, due to the high risk of complications and unpredictable responses.

Models and applications for measuring the impact of health research: update of a systematic review for the Health Technology Assessment programme

BACKGROUND

This report reviews approaches and tools for measuring the impact of research programmes, building on, and extending, a 2007 review.

OBJECTIVES

(1) To identify the range of theoretical models and empirical approaches for measuring the impact of health research programmes; (2) to develop a taxonomy of models and approaches; (3) to summarise the evidence on the application and use of these models; and (4) to evaluate the different options for the Health Technology Assessment (HTA) programme.

DATA SOURCES

We searched databases including Ovid MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature and The Cochrane Library from January 2005 to August 2014.

REVIEW METHODS

This narrative systematic literature review comprised an update, extension and analysis/discussion. We systematically searched eight databases, supplemented by personal knowledge, in August 2014 through to March 2015.

RESULTS

The literature on impact assessment has much expanded. The Payback Framework, with adaptations, remains the most widely used approach. It draws on different philosophical traditions, enhancing an underlying logic model with an interpretative case study element and attention to context. Besides the logic model, other ideal type approaches included constructionist, realist, critical and performative. Most models in practice drew pragmatically on elements of several ideal types. Monetisation of impact, an increasingly popular approach, shows a high return from research but relies heavily on assumptions about the extent to which health gains depend on research. Despite usually requiring systematic reviews before funding trials, the HTA programme does not routinely examine the impact of those trials on subsequent systematic reviews. The York/Patient-Centered Outcomes Research Institute and the Grading of Recommendations Assessment, Development and Evaluation toolkits provide ways of assessing such impact, but need to be evaluated. The literature, as reviewed here, provides very few instances of a randomised trial playing a major role in stopping the use of a new technology. The few trials funded by the HTA programme that may have played such a role were outliers.

DISCUSSION

The findings of this review support the continued use of the Payback Framework by the HTA programme. Changes in the structure of the NHS, the development of NHS England and changes in the National Institute for Health and Care Excellence's remit pose new challenges for identifying and meeting current and future research needs. Future assessments of the impact of the HTA programme will have to take account of wider changes, especially as the Research Excellence Framework (REF), which assesses the quality of universities' research, seems likely to continue to rely on case studies to measure impact. The HTA programme should consider how the format and selection of case studies might be improved to aid more systematic assessment. The selection of case studies, such as in the REF, but also more generally, tends to be biased towards high-impact rather than low-impact stories. Experience for other industries indicate that much can be learnt from the latter. The adoption of researchfish^® (researchfish Ltd, Cambridge, UK) by most major UK research funders has implications for future assessments of impact. Although the routine capture of indexed research publications has merit, the degree to which researchfish will succeed in collecting other, non-indexed outputs and activities remains to be established.

LIMITATIONS

There were limitations in how far we could address challenges that faced us as we extended the focus beyond that of the 2007 review, and well beyond a narrow focus just on the HTA programme.

CONCLUSIONS

Research funders can benefit from continuing to monitor and evaluate the impacts of the studies they fund. They should also review the contribution of case studies and expand work on linking trials to meta-analyses and to guidelines.

FUNDING

The National Institute for Health Research HTA programme.

Statistical analysis plan for the 'Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2)'

Rationale

Glyceryl trinitrate, a nitric oxide donor, is a candidate treatment for acute stroke; it lowers blood pressure, does not alter cerebral blood flow or platelet function and is neuroprotective in experimental stroke. The ongoing rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 trial aims to assess the safety and efficacy of paramedic-delivered glyceryl trinitrate in patients with ultra-acute stroke.Aims and design: The rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 trial is a multicentre UK-based prospective randomised sham-controlled outcome-blinded parallel-group trial in patients with presumed stroke who present to the ambulance service following a 999 emergency call. The primary outcome is the modified Rankin scale measured by central telephone follow-up at 90 days.

Results

This paper describes the statistical analysis plan for the rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 trial and was developed prior to unblinding to treatment allocation. The statistical analysis plan includes details of methods for analyses and unpopulated tables and figures to be included in the primary and other secondary publications.

Discussion

Statistical analysis plan details what analyses will be done prior to unblinding to treatment allocation to avoid bias in the findings. Rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 trial will determine whether glyceryl trinitrate administered ultra-acutely can improve outcome after stroke. The rapid intervention with glyceryl trinitrate in hypertensive stroke trial-2 trial is registered as ISRCTN26986053.

Cerebrolysin for acute ischaemic stroke

BACKGROUND

Cerebrolysin is a mixture of low-molecular-weight peptides and amino acids derived from pigs' brain tissue, which has potential neuroprotective and neurotrophic properties. It is widely used in the treatment of acute ischaemic stroke in Russia, Eastern Europe, China, and other Asian and post-Soviet countries.

OBJECTIVES

To assess the benefits and risks of cerebrolysin for treating acute ischaemic stroke.

SEARCH METHODS

In May 2016 we searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE, Embase, Web of Science Core Collection, with Science Citation Index, LILACS, OpenGrey, and a number of Russian Databases. We also searched reference lists, ongoing trials registers and conference proceedings, and contacted the manufacturer of cerebrolysin, EVER Neuro Pharma GmbH (formerly Ebewe Pharma).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing cerebrolysin, started within 48 hours of stroke onset and continued for any time, with placebo or no treatment in people with acute ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied inclusion criteria, assessed trial quality and risk of bias, and extracted data.

MAIN RESULTS

We identified six RCTs (1501 participants) that met the inclusion criteria.We evaluated risk of bias and judged it to be unclear for generation of allocation sequence in four studies and low in two studies; unclear for allocation concealment in five studies and low in one study; high for incomplete outcome data (attrition bias) in five studies and unclear in one study; unclear for blinding; high for selective reporting in four studies and unclear in two; and high for other sources of bias in three studies and unclear in the rest. The manufacturer of cerebrolysin, pharmaceutical company EVER Neuro Pharma, supported three multi-centre studies, either totally, or providing cerebrolysin and placebo, randomisation codes, research grants, or statisticians.None of the included trials reported on poor functional outcome defined as death or dependence at the end of the follow-up period or early death (within two weeks of stroke onset).All-cause death: we extracted data from five trials (1417 participants). There was no difference in the number of deaths: 46/714 in cerebrolysin group versus 47/703 in placebo group; risk ratio (RR) 0.91 95% confidence interval (CI) 0.61 to 1.35 (5 trials, 1417 participants, moderate-quality evidence).Serious adverse events (SAEs): there was no significant difference in the total number of SAEs with cerebrolysin (RR 1.16, 95% CI 0.81 to 1.67). This comprised no difference in fatal SAEs (RR 0.90, 95% CI 0.59 to 1.38) and an increase in the number of people with non-fatal SAEs (20/667 with cerebrolysin and 8/668 with placebo: RR 2.47, 95% CI 1.09 to 5.58, P = 0.03) (3 trials, 1335 participants, moderate-quality evidence).Total number of people with adverse events: three trials reported on this. There was no difference in the total number of people with adverse events: 308/667 in cerebrolysin group versus 307/668 in placebo group; RR 0.97 95% CI 0.86 to 1.09, random-effects model (3 trials, 1335 participants, moderate-quality evidence).

AUTHORS' CONCLUSIONS

The findings of this Cochrane Review do not demonstrate clinical benefits of cerebrolysin for treating acute ischaemic stroke. We found moderate-quality evidence of an increase in non-fatal SAEs with cerebrolysin use but not in total SAEs.