Secondary Stroke Prevention: From Guidelines to Clinical Practice

Antiplatelet agents for the secondary prevention of ischaemic stroke in patients with or without renal dysfunction

BACKGROUND AND PURPOSE

Studies on using antiplatelet agents for secondary prevention in ischaemic stroke patients with renal dysfunction are limited. The Taiwan Stroke Registry database was used to compare the efficacy of antiplatelet agents.

METHODS

From the Taiwan Stroke Registry data, 39 174 acute ischaemic stroke patients were identified and were classified into three groups by antiplatelet agent: aspirin, clopidogrel and dual antiplatelet therapy (DAPT) with a combination of aspirin and clopidogrel. The re-stroke incidence and 1-year mortality were stratified by estimated glomerular filtration rate (eGFR) levels at admission: ≥90, 60-89 and <60 ml/min/1.73 m² or on dialysis.

RESULTS

Compared to the aspirin group, the re-stroke differences were not statistically significant for the clopidogrel group [adjusted subhazard ratio 0.95, 95% confidence interval (CI) 0.84-1.08] and the DAPT group (adjusted subhazard ratio 1.03, 95% CI 0.77-1.39) after controlling for the competing risk of death. The mortality rate increased as the eGFR level declined. In addition, compared to patients taking aspirin, there was no statistically significant difference in overall 1-year mortality for the clopidogrel group (adjusted hazard ratio 1.11, 95% CI 0.95-1.29) and for the DAPT group (adjusted hazard ratio 1.01, 95% CI 0.67-1.54). The results were consistent in different subgroups stratified by eGFR levels.

CONCLUSIONS

There was no difference in the risks of recurrent stroke and 1-year mortality amongst ischaemic stroke patients with or without renal dysfunction receiving antiplatelet agents with aspirin, clopidogrel or dual agents with a combination of aspirin and clopidogrel, regardless of their renal dysfunction status.

Cilostazol for treatment of cerebral infarction

INTRODUCTION

Stroke not only causes critical disability and death but is also a cause of anxiety with the possibility of secondary cardiovascular events including secondary ischemic stroke. Indeed, patients with a history of previous stroke have a high rate of stroke recurrence, indicating the clinical importance of secondary stroke prevention. Area of covered: This review provides an overview of the pooled evidence for cilostazol's use in the management of secondary stroke prevention. Among the various antiplatelet agents that are available, aspirin is the most frequently used agent worldwide for the prevention of secondary stroke. Cilostazol, a selective phosphodiesterase (PDE) 3A inhibitor, is used worldwide for the treatment of patients with intermittent claudication. However, in Asia, cilostazol is recommended and used in practice for secondary stroke prevention. Expert opinion: The authors believe that cilostazol could be used for secondary stroke prevention not only in Asia but worldwide. However, further randomized trials on cilostazol are needed, especially in the US and Europe to better support its case.

Risk Focused Screening for Vascular Disease: One University Hospital's Experience

Introduction

Vascular screening programs have been gaining popularity in recent years; however, most programs accept all patients willing to participate. This study was designed to determine the yield of disease when screening examinations are limited to those most at risk, to stratify the amount of disease present in the at-risk population, and to establish which patients might benefit most from vascular screening.

Materials and Methods

Patients enrolled in a community outreach program for seniors 55 years of age and older were asked to participate in a free vascular screening. Screenings consisted of completion of a questionnaire, physical examination, limited carotid artery evaluation for stenosis, aorta evaluation for detection of aneurysm, and ankle/brachial index (ABI) calculation to detect peripheral vascular disease. Findings were grouped into “Normal,” “Mild disease,” and “Significant disease.” Findings were then compared with the following controllable risk factors: hypertension, hyperlipidemia, diabetes, coronary artery disease (CAD), or smoking history.

Results

Between May 16 and October 17, 2007, 357 participants' (75 male, 157 female, mean age 72.9 years) results were analyzed. Overall, 140 participants (43%) had some form of vascular disease (“mild” and “significant” categories combined). Of 324 eligible participants, carotid findings showed 199 normal (61%), 104 mild (32%), and 21 significant (7%) results. Aorta findings showed 296 normal (91%), 25 mild (8%), and 3 significant (1%) results. ABI findings showed 278 normal (86%), 18 mild (6%), and 28 significant (8%) results. In participants with three or more risk factors, there was a greater probability that carotid ( p = 0.0022) and peripheral vascular disease ( p = 0.0003) would be detected; however, there was no predictive value for aortic aneurysm ( p = 0.5).

Conclusion

Vascular screening programs focusing on the at-risk population may reduce unnecessary testing compared with programs evaluating all patients willing to participate.

Association of Rs2071410 on Furin with Transient Ischemic Attack Susceptibility and Prognosis in a Chinese Population

Background

Because genotype CG/GG of Furin rs2071410 can increase susceptibility to hypertension, this study investigated whether Furin rs2071410 is correlated with transient ischemic attack (TIA) susceptibility and prognosis.

Material/Methods

The odds ratios (ORs) and their 95% confidence intervals (95% CIs) were evaluated to assess the association of rs2071410 with TIA risk, and logistic regression was used to estimate the effects of various risk factors (e.g., diabetes, hypertension, and hyperlipidemia) on TIA.

Results

Compared with the homozygous genotype CC of rs2071410, the frequency of CG + GG genotype in the case group was significantly higher than in the control group (OR=1.47, 95% CI: 1.05–2.05, P<0.05). The CG + GG genotype carriers were observed to have worse 90-day prognosis after TIA treatment than patients carrying CC genotype (OR=12.86, 95% CI: 7.41–22.33, P<0.05). Moreover, logistic regression analysis found that age, diabetes, hypertension, and hyperlipidemia were associated with the onset of TIA (P<0.05, all). Of note, individuals with CG + GG genotype had 49.3% increased risk of TIA compared with individuals with CC genotype (OR=1.49, 95% CI: 1.05–2.12), and patients with CG + GG genotype had worse 90-day prognosis after TIA treatment than patients with CC genotype (OR=11.39, 95% CI: 6.29–20.62).

Conclusions

Furin rs2071410 was significantly correlated with TIA occurrence and prognosis in the Chinese population.

Antiplatelet regimens in the long-term secondary prevention of transient ischaemic attack and ischaemic stroke: an updated network meta-analysis

OBJECTIVE

To examine the comparative efficacy and safety of different antiplatelet regimens in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

As on 31 March 2015, all randomised controlled trials that investigated the effects of antiplatelet agents in the long-term (≥ 3 months) secondary prevention of non-cardioembolic transient ischaemic attack or ischaemic stroke were searched and identified.

OUTCOME MEASURES

The primary outcome measure of efficacy was serious vascular events (non-fatal stroke, non-fatal myocardial infarction and vascular death). The outcome measure of safety was any bleeding.

RESULTS

A total of 36 randomised controlled trials (82,144 patients) were included. Network meta-analysis showed that cilostazol was significantly more effective than clopidogrel (OR 0.77, 95% credible interval 0.60-0.98) and low-dose (75-162 mg daily) aspirin (0.69, 0.55-0.86) in the prevention of serious vascular events. Aspirin (50 mg daily) plus dipyridamole (400 mg daily) and clopidogrel reduced the risk of serious vascular events compared with low-dose aspirin; however, the difference was not statistically significant. Furthermore, low-dose aspirin was as effective as higher daily doses. Cilostazol was associated with a significantly lower bleeding risk than most of the other regimens. Moreover, aspirin plus clopidogrel was associated with significantly more haemorrhagic events than other regimens. Direct comparisons showed similar results as the network meta-analysis.

CONCLUSIONS

Cilostazol was significantly more effective than aspirin and clopidogrel alone in the long-term prevention of serious vascular events in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack. Cilostazol was associated with a significantly lower bleeding risk than low-dose aspirin (75-162 mg daily) and aspirin (50 mg daily) plus dipyridamole (400 mg daily). Low-dose aspirin was as effective as higher daily doses. However, further large, randomised, controlled, head-to-head trials are needed, especially in non-Asian ethnic groups.

Improving Adherence to Secondary Stroke Prevention Strategies Through Motivational Interviewing: Randomized Controlled Trial

BACKGROUND AND PURPOSE

Stroke recurrence rates are high (20%-25%) and have not declined over past 3 decades. This study tested effectiveness of motivational interviewing (MI) for reducing stroke recurrence, measured by improving adherence to recommended medication and lifestyle changes compared with usual care.

METHODS

Single-blind, prospective phase III randomized controlled trial of 386 people with stroke assigned to either MI treatment (4 sessions at 28 days, 3, 6, and 9 months post stroke) or usual care; with outcomes assessed at 28 days, 3, 6, 9, and 12 months post stroke. Primary outcomes were change in systolic blood pressure and low-density lipoprotein cholesterol levels as indicators of adherence at 12 months. Secondary outcomes included self-reported adherence, new stroke, or coronary heart disease events (both fatal and nonfatal); quality of life (Short Form-36); and mood (Hospital Anxiety and Depression Scale).

RESULTS

MI did not significantly change measures of blood pressure (mean difference in change, -0.2.35 [95% confidence interval, -6.16 to 1.47]) or cholesterol (mean difference in change, -0.0.12 [95% confidence interval, -0.30 to 0.06]). However, it had positive effects on self-reported medication adherence at 6 months (1.979; 95% confidence interval, 0.98-3.98; P=0.0557) and 9 months (4.295; 95% confidence interval, 1.56-11.84; P=0.0049) post stroke. Improvement across other measures was also observed, but the differences between MI and usual care groups were not statistically significant.

CONCLUSIONS

MI improved self-reported medication adherence. All other effects were nonsignificant, though in the direction of a treatment effect. Further study is required to determine whether MI leads to improvement in other important areas of functioning (eg, caregiver burden).

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au. Unique identifier: ACTRN-12610000715077.

Secondary prevention of stroke in Saskatchewan, Canada: hypertension control

BACKGROUND

In the province of Saskatchewan, Canada, stroke is the third leading cause of death as well as the major cause of adult disability. Once a person suffers a stroke or transient ischemic attack (TIA), they are at high risk for having a secondary stroke. Hypertension (elevated blood pressure) is the single most important modifiable risk factor for both first and recurrent stroke, and is thus an important risk factor to be controlled. According to the Canadian Stroke Strategy (CSS) Best Practice Recommendations, blood pressure lowering treatment should be initiated before discharge from hospital for all stroke/TIA patients. The purpose of this study was to examine the quality of medically driven secondary stroke prevention care in Saskatchewan as applied to hypertension control.

AIMS

The objectives of the study were to: (1) develop methodology and calculate a secondary stroke process of care measure using available data in Saskatchewan, based on an appropriate hypertension therapy indicator recommendation from the CSS Performance Measurement Manual; (2) examine variation in secondary stroke prevention hypertensive care among the Saskatchewan Regional Health Authorities; and (3) investigate factors associated with receiving evidence-based hypertensive secondary stroke prevention.

METHODS

This multi-year cross-sectional study was an analysis of deidentified health data derived from linkage of administrative health data. A select indicator from the CSS Performance Measurement Manual that measures adherence to a CSS Best Practice Guidelines concerning use of antihypertensive medications for secondary stroke prevention was calculated. Logistic regression was used to quantify the association of patient demographic and socioeconomic characteristics and geographic location of care with receipt of guideline-recommended hypertensive secondary stroke prevention. The target population was all Saskatchewan residents who were hospitalized in Saskatchewan for a stroke or TIA between April 1, 2001 and March 31, 2008.

RESULTS

The results of this study indicate that the management of hypertension for secondary stroke prevention is sub-optimal in Saskatchewan. Although there was some improvement over the time period, approximately 40% of patients were not taking antihypertensives at 90 days after discharge from acute care. The correlates, urban/non-urban, previous use of antihypertensive drugs and effect of age modified by sex, were found to be significantly associated with receiving hypertensive secondary stroke prevention, suggesting there are modifiable factors that contribute to variations in this form of secondary stroke care quality in Saskatchewan.

CONCLUSIONS

The results of this study suggest that there is a need for province-wide improvement to secondary stroke prevention in Saskatchewan, Canada.

Secondary prevention of stroke: Pleiotropic effects of optimal oral pharmacotherapy

Stroke is a major cause of mortality and disability worldwide. During the past three decades, major advances have occurred in secondary prevention, which have demonstrated the broader potential for the prevention of stroke. Risk factors for stroke include previous stroke or transient ischemic attack, hypertension, high blood cholesterol and diabetes. Proven secondary prevention strategies are anti-platelet agents, antihypertensive drugs, statins and glycemic control. In the present review, we evaluated the secondary prevention of stroke in light of clinical studies and discuss new pleiotropic effects beyond the original effects and emerging clinical evidence, with a focus on the effect of optimal oral pharmacotherapy.

Clinical characteristics of early and late recurrent ischaemic stroke

BACKGROUND AND PURPOSE

The aim of the study was to search for differences between clinical characteristics of recurrent ischaemic stroke which occurred within the fifth year after the first event or later, and early recurrence, i.e. within the first year after first-ever ischaemic stroke. We also tried to determine prognostic factors of late recurrent ischaemic episodes.

MATERIAL AND METHODS

The patients were divided into two groups: group I comprised 124 individuals with recurrence within the first year, and group II - 98 individuals in whom the recurrent episode appeared within the fifth year or later.

RESULTS

A significantly higher percentage of patients in group I demonstrated evident stenosis (70% or more) of internal carotid artery ipsilateral to stroke (p = 0.023). In this group more cardioembolic strokes were found compared to group II, while in the latter, predominantly lacunar strokes appeared (p = 0.046 and 0.0002, respectively). Group II patients significantly more frequently reported acetylsalicylic acid application, including systematic drug use (p = 0.001). No evident differences were found between groups considering other important non-modifiable and modifiable risk factors of stroke.

CONCLUSIONS

Small differences between risk factors of ischaemic stroke profiles in patients with early and late recurrent episodes do not allow us to distinguish unequivocally a group of patients with better prognosis regarding the time of recurrent stroke. Use of antiplatelet drugs, either systematic or non-systematic, and lacunar stroke are independent, positive prognostic factors of delay of potential recurrent stroke.

Blood pressure treatment in acute ischemic stroke: a review of studies and recommendations

PURPOSE OF REVIEW

Elevated blood pressure (BP) is frequent in patients with acute ischemic stroke. Pathophysiological data support its usefulness to maintain adequate perfusion of the ischemic penumba. This review article aims to summarize the available evidence from clinical studies that examined the prognostic role of BP during the acute phase of ischemic stroke and intervention studies that assessed the efficacy of active BP alteration.

RECENT FINDINGS

We found 34 observational studies (33,470 patients), with results being inconsistent among the studies; most studies reported a negative association between increased levels of BP and clinical outcome, whereas a few studies showed clinical improvement with higher BP levels, clinical deterioration with decreased BP, or no association at all. Similarly, the conclusions drawn by the 18 intervention studies included in this review (1637 patients) were also heterogeneous. Very recent clinical data suggest a possible beneficial effect of early treatment with some antihypertensives on late clinical outcome.

SUMMARY

Observational and interventional studies of management of acute poststroke hypertension yield conflicting results. We discuss different explanations that may account for this and discuss the current guidelines and pathophysiological considerations for the management of acute poststroke hypertension.

Vascular risk factors for central retinal artery occlusion

PURPOSE

To determine the proportion of patients presenting with thromboembolic central retinal artery occlusion (CRAO) who had undiagnosed vascular risk factors amenable to modification.

METHODS

A retrospective audit of consecutive patients with non-arteritic/thromboembolic CRAO presenting between 1997 and 2008 in a single tertiary teaching hospital.

RESULTS

Thirty-three patients with non-arteritic CRAO were identified. Twenty-one patients (64%) had at least one new vascular risk factor found after the retinal occlusive event, with hyperlipidemia being the most common undiagnosed vascular risk factor at the time of the sentinel CRAO event (36%). Nine patients (27%) had newly diagnosed hypertension or previous diagnosis of hypertension but not optimally controlled. To better control their vascular risk factors 18 patients (54%) were given a new or altered medication. Nine patients had more than 50% of ipsilateral carotid stenosis ; six of these proceeded with carotid endarterectomy or stenting. One patient had significant new echocardiogram finding. Systemic ischaemic event post CRAO occurred in two patients with stroke and acute coronary syndrome.

CONCLUSIONS

Patients presenting with CRAO often have a previously undiagnosed vascular risk factor that may be amenable to medical or surgical treatment. As this population is at a high risk of secondary ischaemic events, risk factor modification is prudent.

Cognitive Risks of Dyslipidemia

This review discusses evidence-based perspectives on the relationship between dyslipidemia and cognitive decline, including strategic implications for risk reduction in primary care and empirically driven public policy initiatives to prevent cognitive dysfunction.