American Heart Association; American Stroke Association Stroke Council. Primary prevention of ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council: co-sponsored by the Atherosclerotic Peripheral Vascular Disease Interdisciplinary Working Group; Cardiovascular Nursing Council; Clinical Cardiology Council; Nutrition, Physical Activity, and Metabolism Council; and the Quality of Care and Outcomes Research Interdisciplinary Working Group

Effect of a Nurse-Led Education Program for Stroke Patients on Sleep Quality and Quality of Life: A Randomized Controlled Study

Nurse-led education and follow-up for stroke patients may facilitate management and improve quality of life. This study investigated the effect of a nurse-led education program for stroke patients on sleep and life quality. A total of 92 stroke patients (46 in the intervention group, 46 in the control group) aged 18 to 75 years who were independently mobile (less than or equal to one assistive device) and had no other neurologic or psychiatric disorders or history of sleep disorder prior to stroke were included. Patients randomized to the intervention group completed a 20-week education and follow-up program including information about stroke, rehabilitation, adaptation to daily life, and the importance of sleep quality. In the posttest, the intervention group had significantly higher sleep quality and stroke-specific quality of life scores than the control group. This study may serve as a guide for nurses who work with stroke patients.

Catalpol protects vascular structure and promotes angiogenesis in cerebral ischemic rats by targeting HIF-1α/VEGF

BACKGROUND

The initial factor in the occurrence, development, and prognosis of cerebral ischemia is vascular dysfunction in the brain, and vascular remodeling of the brain is the key therapeutic target and strategy for ischemic tissue repair. Catalpol is the main active component of the radix of Rehmannia glutinosa Libosch, and it exhibits potential pleiotropic protective effects in many brain-related diseases, including stroke.

PURPOSE

The present study was designed to investigate whether catalpol protects vascular structure and promotes angiogenesis in cerebral ischemic rats and to identify its possible mechanisms in vivo and in vitro.

STUDY DESIGN

Cerebral ischemic rats and oxygen-glucose deprivation-exposed brain microvascular endothelial cells were used to study the therapeutic potential of catalpol in vivo and in vitro.

METHODS

First, neurological deficits, histopathological morphology, infarct volume, vascular morphology, vessel density, and angiogenesis in focal cerebral ischemic rats were observed to test the potential treatment effects of catalpol. Then, oxygen-glucose deprivation-exposed brain microvascular endothelial cells were used to mimic the pathological changes in vessels during ischemia to study the effects and possible mechanisms of catalpol in protecting vascular structure and promoting angiogenesis.

RESULTS

The in vivo results showed that catalpol reduced neurological deficit scores and infarct volume, protected vascular structure, and promoted angiogenesis in cerebral ischemic rats. The in vitro results showed that catalpol improved oxygen-glucose deprivation-induced damage and promoted proliferation, migration, and in vitro tube formation of brain microvascular endothelial cells. The HIF-1α (hypoxia-inducible factor 1α)/VEGF (vascular endothelial growth factor) pathway was activated by catalpol both in the brains of cerebral ischemic rats and in primary brain microvascular endothelial cells, and the activating effects of catalpol were inhibited by SU1498.

CONCLUSION

The results of both the in vivo and in vitro studies proved that catalpol protects vascular structure and promotes angiogenesis in focal cerebral ischemic rats and that the mechanism is dependent on HIF-1α/VEGF.

The Probability of Ischaemic Stroke Prediction with a Multi-Neural-Network Model

As is known, cerebral stroke has become one of the main diseases endangering people’s health; ischaemic strokes accounts for approximately 85% of cerebral strokes. According to research, early prediction and prevention can effectively reduce the incidence rate of the disease. However, it is difficult to predict the ischaemic stroke because the data related to the disease are multi-modal. To achieve high accuracy of prediction and combine the stroke risk predictors obtained by previous researchers, a method for predicting the probability of stroke occurrence based on a multi-model fusion convolutional neural network structure is proposed. In such a way, the accuracy of ischaemic stroke prediction is improved by processing multi-modal data through multiple end-to-end neural networks. In this method, the feature extraction of structured data (age, gender, history of hypertension, etc.) and streaming data (heart rate, blood pressure, etc.) based on a convolutional neural network is first realized. A neural network model for feature fusion is then constructed to realize the feature fusion of structured data and streaming data. Finally, a predictive model for predicting the probability of stroke is obtained by training. As shown in the experimental results, the accuracy of ischaemic stroke prediction reached 98.53%. Such a high prediction accuracy will be helpful for preventing the occurrence of stroke.

Temporal Trends and Patient Characteristics Associated With Drug Utilisation After First-Ever Stroke: Insights From Chronic Disease Registry Data in Singapore

Introduction: Data on drug utilisation among stroke patients of Asian ethnicities are lacking. The objectives of the study were to examine the temporal trends and patient characteristics associated with prescription of thrombolytic, antithrombotic and statin medications among patients with first-ever stroke. Materials and Methods: First-ever ischaemic and haemorrhagic stroke patients admitted to 2 Singapore tertiary hospitals between 2010‒2014 were included. Data were extracted from the National Healthcare Group Chronic Disease Management System. Association between drug utilisation and admission year, as well as characteristics associated with drug use, were explored using multivariable logistic regression. Results: There was an increasing trend in the combined use of all 3 guideline medications in ischaemic stroke patients (P<0.001) ―specifically thrombolytic agents (P <0.001), oral antithrombotics (P = 0.002) and statins (P = 0.003) at discharge. Among antithrombotics, the use of clopidogrel (P <0.001) and aspirinclopidogrel (P <0.001) had increased, whereas prescription of dipyridamole (P <0.001) and aspirin-dipyridamole (P <0.001) had declined. For statins, the increase in atorvastatin prescription (P <0.001) was accompanied by decreasing use of simvastatin (P <0.001). Age, ethnicity and certain comorbidities (hyperlipidaemia, atrial fibrillation and chronic kidney disease) were associated with the combined use of all 3 guideline medications (P <0.05). In haemorrhagic stroke, prescription of statins at discharge were comparatively lower. Conclusion: This study reveals changes in prescription behaviour over time in a multiethnic Asian population with first-ever stroke. Patient characteristics including younger age, Malay ethnicity and certain comorbidities (i.e. hyperlipidaemia, atrial fibrillation) were associated with the combined use of all 3 guideline medications among ischaemic stroke patients. Key words: Antithrombotics, Asian, Statins, Thrombolytic agents

Ischaemic stroke and bleeding rates in ‘real-world’ atrial fibrillation patients

Stroke prevention guidelines recommend oral anticoagulants (OAC) for atrial fibrillation (AF) patients at moderate/high risk of stroke, and antiplatelet or no therapy for those at low/moderate risk. Outcomes for AF patients receiving antiplatelet/no therapy in ‘real-life’ clinical practice were explored. This study compared clinical event rates (stroke/bleeding) for AF patients treated with OAC therapy, antiplatelets or no therapy in usual clinical practice to event rates in OAC-treated AF patients from optimally-monitored ‘real-life’ settings (anticoagulation clinics). We searched biomedical literature (1994–2010) using PubMed to identify ‘real-world’ studies of clinical event rates for AF patients receiving OAC therapy, antiplatelets, or no therapy; event rates were extracted for each treatment and setting. We identified 136 studies of thromboembolic events and 86 of bleeding events. Ischaemic stroke rates (30 studies) were higher for AF patients receiving no therapy (median: 4.45/100 person-years; range: 0.25–5.9) or antiplatelet-therapy (median: 4.45/100 person-years; range: 2.0–10) compared to OACtreated patients monitored in anticoagulation clinics (median: 1.72/100 person-years; range: 0.97–2.00), or from a non-specialized setting (median 1.66/100 person-years; range: 0–4.9). Major bleeding rates (32 studies) for patients receiving antiplatelet/no therapy were similar to OAC-treated patients from both clinical settings. As in randomised clinical trials, AF patients in ‘real-world’ clinical practice receiving antiplatelet/no therapy have higher rates of ischaemic stroke than OAC-treated patients. Antiplatelet/no therapy was associated with similar bleeding rates to OAC therapy. Increasing utilisation of anticoagulants in clinical practice could improve patient outcomes.

The circle of Willis predicts the antihypertensive effects of carotid artery stenting

OBJECTIVE Carotid artery stenting (CAS) has antihypertensive effects, but the durability and degree of this response remain variable. The authors propose that this clinical variability is a function of the presence or absence of a complete circle of Willis (COW). Incomplete COWs perfuse through a higher-resistance pial collateral pathway, and therefore patients may require a higher mean arterial pressure (MAP). Carotid artery revascularization in these patients would reduce the end-organ collateral demand that has been hypothesized to drive the MAP response. METHODS Using a retrospective, nonrandomized within-subject case-control design, the authors compared the postoperative effects of CAS in patients with and without a complete COW by using changes in MAP and antihypertensive medication as end points. They recorded MAP and antihypertensive medications 3 months prior to surgery, preoperatively, immediately postoperatively, and at the 3-month follow-up. RESULTS Data were collected from 64 consecutive patients undergoing CAS. Patients without a complete COW (25%) were more likely to demonstrate a decrease in BP response to stenting (i.e., a drop in MAP of 10 mm Hg and/or a reduction or cessation of BP medications at 3 months postoperatively). Of the patients in the incomplete COW cohort, 75% had this outcome, whereas of those in the complete COW cohort, only 41% had it (p < 0.041). These findings remained statistically significant in a logistic regression analysis for possible confounders (p < 0.024). A receiver operating curve analysis of preoperative data indicated that a MAP > 96.3 mm Hg was 55.5% sensitive and 57.4% specific for predicting a complete COW and that patients with a MAP > 96.3 mm Hg were more likely to demonstrate a good MAP decrease following CAS (p < 0.0092). CONCLUSIONS CAS is associated with a significant decrease in MAP and/or a reduction/cessation in BP medications in patients in whom a complete COW is absent.

Similar enhancement of BK(Ca) channel function despite different aerobic exercise frequency in aging cerebrovascular myocytes

Aerobic exercise showed beneficial influence on cardiovascular systems in aging, and mechanisms underlying vascular adaption remain unclear. Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels play critical roles in regulating cellular excitability and vascular tone. This study determined the effects of aerobic exercise on aging-associated functional changes in BK(Ca) channels in cerebrovascular myocytes, Male Wistar rats aged 20-22 months were randomly assigned to sedentary (O-SED), low training frequency (O-EXL), and high training frequency group (O-EXH). Young rats were used as control. Compared to young rats, whole-cell BK(Ca) current was decreased, and amplitude of spontaneous transient outward currents were reduced. The open probability and Ca(2+)/voltage sensitivity of single BK(Ca) channel were declined in O-SED, accompanied with a reduction of tamoxifen-induced BK(Ca) activation; the mean open time of BK(Ca) channels was shortened whereas close time was prolonged. Aerobic exercise training markedly alleviated the aging-associated decline independent of training frequency. Exercise three times rather than five times weekly may be a time and cost-saving training volume required to offer beneficial effects to offset the functional declines of BK(Ca) during aging.

Exercise as stroke prophylaxis

BACKGROUND

Stroke is the third most common cause of death in industrialized countries, accounting for more than 10% of deaths over age 65. Most strokes are due to arteriosclerosis. Regular physical activity lowers arterial blood pressure and body weight and improves glucose and lipid metabolism, thereby slowing the development of arteriosclerosis and its cardiovascular complications, particularly myocardial infarction. This review focuses on the question whether physical activity might also have a preventive effect on cerebral infarction and hemorrhage.

METHODS

This analysis is based on 33 prospective cohort studies and 10 case-control studies that addressed the potential effect of physical activity on stroke-related morbidity and mortality.

RESULTS

Our meta-analysis shows that physical activity reduces the risk of all types of stroke (infarction, hemorrhage, and stroke of unspecified type). The relative risk (RR) of fatal or non-fatal cerebral infarction is 0.75, while the corresponding figures for cerebral hemorrhage and stroke of unspecified type are 0.67 and 0.71, respectively. The reduction of risk is only statistically significant for men. The case-control studies show an RR of 0.32 for men and women combined.

CONCLUSIONS

When a multivariate analysis is performed that takes other vascular risk factors into account, physical activity is found to have an independent protective effect against cerebrovascular events. The effect is statistically significant only for men, not for women.

Ultrasound Assisted Thrombolysis in Acute Ischaemic Stroke: Preliminary Experience in Singapore

Background and Aim: Intravenously-administered tissue plasminogen activator (IV-TPA) induces thrombolysis and remains the only FDA-approved therapy for acute ischaemic stroke. IV-TPA thrombolysis has been approved recently in Singapore for acute stroke. Continuous exposure of clot to 2-MHz pulsed-wave transcranial Doppler (TCD) ultrasound during IV-TPA infusion is known to augment thrombolysis. We aimed to determine the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore. Subjects and Methods: Consecutive patients with acute ischaemic stroke due to intracranial arterial-occlusions were treated with standard IV-tPA and continuously monitored with 2-MHz TCD according to the CLOTBUST-trial protocol. Arterial recanalisation was determined with Thrombolysis in Brain Ischemia (TIBI) flow-grading system. Safety and efficacy of ultrasoundassisted thrombolysis were assessed by rates of symptomatic intracranial haemorrhage (sICH) and functional recovery at 1 month, respectively. Results: Five consecutive patients (mean age 58 years, 3 men and 3 of Chinese ethnicity) were included. Mean time elapsed between symptom onset and presentation to emergency room was 98 minutes (range, 50 to 135 minutes) while the mean time interval between symptom onset to IV-TPA bolus was 144 minutes (range, 125 to 180 minutes). Partial or complete recanalisation with reduction in the stroke severity was noted in 4 out of the 5 patients during IV-TPA infusion (mean change in NIHSS = 4 points; range 2 to 8 points). None of our patients developed sICH while 4 patients demonstrated good functional outcome at 1 month. Conclusions: Our preliminary study demonstrates the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore. Continuous TCD-monitoring during IV-TPA infusion provides real-time information, enhances thrombolysis and improves functional outcomes in acute ischaemic stroke. Key words: Acute ischaemic stroke, Thrombolysis, Transcranial Doppler

Bridging the Gap Between Primary and Specialist Care – An Integrative Model for Stroke

Stroke is a major cause of death and disability in Singapore and many parts of the world. Chronic disease management programmes allow seamless care provision across a spectrum of healthcare facilities and allow appropriate services to be brought to the stroke patient and the family. Randomised controlled trials have provided evidence for efficacious interventions. After the management of acute stroke in a stroke unit, most stable stroke patients can be sent to their family physician for continued treatment and rehabilitation supervision. Disabled stroke survivors may need added home-based services. Suitable community resources will need to be harnessed. Clinic-based stroke nurses may enhance service provision and coordination. Close collaboration between the specialist and family physician would be needed to right-site patients and also allow referrals in either direction where necessary. Barriers to integration can be surmounted by trust and improved communication. Audits would allow monitoring of care provision and quality care enhancement. The Wagner model of chronic care delivery involves self-management support, shared clinical information systems, delivery system redesign, decision support, healthcare organisation and community resources. The key and critical feature is the need for an informed, activated (or motivated) patient, working in collaboration with the specialist and family physician, and a team of nursing and allied healthcare professionals across the continuum of care. The 3-year Integrating Services and Interventions for Stroke (ISIS) project funded by the Ministry of Health will test such an integrative system. Key words: Cerebrovascular disease, Chronic disease management, Family physician, Neurologist, Stroke nurse