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.

Elevated Free Fatty Acid is Associated with Cardioembolic Stroke Subtype

Background and Objectives:

Free fatty acids (FFAs), an important energy substrate, have an association with cardiovascular diseases, such as atherosclerosis, myocardial dysfunction and abnormal cardiac rhythm. However, limited reports are available on the association between FFAs and ischemic stroke. We hypothesized that plasma FFA concentration could be associated with an ischemic stroke, emphasizing the relationship between FFA and subtypes of ischemic stroke.

Methods:

A cross-sectional study examined the association between FFA concentration and subtypes of stroke and cerebral atherosclerosis from a hospital-based acute stroke registry.

Results:

Data of 715 stroke patients were analyzed. The concentration of FFA was highest in the cardioembolic stroke subtype compared with the other stroke subtypes. Logistic regression analysis revealed that an increase in FFA concentration was significantly associated with the cardioembolic subtype after the adjustment of covariates. FFA concentration was also higher in patients with atrial fibrillation (AF) than those without AF. According to the presence of atherosclerotic stenosis, no significantly difference of FFA concentration was found for intracranial and extracranial cerebral arterial atherosclerosis.

Conclusion:

Here we report a significant association between fasting FFA concentration and the cardioembolic stroke subtype. AF is suggested as the mediating factor between FFA and the cardioembolic stroke subtype.

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.

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.

Ambulatory blood pressure monitoring in stroke survivors: do we really control our patients?

BACKGROUND

We aim to evaluate prospectively the long-term changes of blood pressure (BP) in stroke survivors using ambulatory BP monitoring (ABPM) and compare them with the clinic conventional measurements.

METHODS

We studied 101 patients who were admitted within 24h after stroke onset. To study the circadian rhythm of BP a continuous BP monitor (Spacelab 90207) was used. After six and twelve months follow-up a new ABPM was undertaken. Data were analyzed using the SSPS 12.0.

RESULTS

We studied 62 males and 39 females, mean age: 70.9+/-10.7 years. We included 88 ischemic strokes and 13 hemorrhagic strokes. In the acute phase mean 24 h BPs were 136+/-19/78.6+/-11.4 mm Hg. The normal diurnal variation in BP was abolished in 88 (87.1%) patients. After six months, 74 patients were assessed. Mean office readings were 137.5+/-23.8/76.4+/-11.4 mm Hg, and high systolic BPs and diastolic BPs were found in 37% and 11% of the subjects respectively. ABPM revealed a mean BP of 118.5+/-20.1/70.3+/-8.6 (p<0.0001). In 57 (76.9%), the normal BP pattern remained abolished (p<0.001). After one year, 63 patients were assessed. Mean office readings were 130.8+/-26.3/77.6+/-9.3 mm Hg, and high systolic BPs and diastolic BPs were found in 23.8% and 10% of the subjects respectively. Mean 24 h BPs were 117+/-12.5/69.7+/-7.2 (p<0.001). The normal diurnal variation in BP was now abolished in 47 (74.6%) patients (p<0.001).

CONCLUSION

Survivors of stroke, both hypertensive and non-hypertensive patients, present a chronic disruption of circadian rhythm of BP. Conventional clinical recordings are an unreliable method of controlling these patients and ABPM should be routinely performed in this population.

Withdrawal of fenofibrate treatment partially abrogates preventive neuroprotection in stroke via loss of vascular protection

To explore the mechanisms of action of preventive neuroprotection induced by PPAR-alpha activation, we have evaluated the neuronal, vascular effects of preventive treatment with fenofibrate up until the induction of experimental brain ischaemia and fenofibrate treatment withdrawn 3days before ischaemia induction. Fenofibrate (200mg/kg/day) was administered in rats for 14days or withdrawn 3days before induction of cerebral ischaemia. Animals underwent a 1-hour middle cerebral artery occlusion (MCAo), followed by reperfusion for 24h. The MCA's vasoreactivity was analyzed and brain sections were used to assess infarct size, inflammatory and oxidative stress markers. Fenofibrate administration significantly decreases the cerebral infarct volume. This effect was associated with partial prevention of post-ischaemic endothelial dysfunction. However, withdrawal of the fenofibrate treatment 3days before the induction of ischaemia reduced the neuroprotection and was less beneficial in preventing endothelial dysfunction as well as superoxide anion production. In contrast, fenofibrate significantly reduced microglial activation and neutrophil infiltration into the ischaemic zone to a similar extent in both treatment modes. Our results show that the fenofibrate-induced cerebral protective effect may be related to both an acute effect and a preconditioning-like mechanism. The vascular protective effect appears rather to translate the acute effects of fenofibrate administration.

Pharmacotherapy in stroke rehabilitation

BACKGROUND

Pharmacotherapy is commonly given to patients recovering from a stroke to prevent further complications (e.g. recurrent stroke, seizures) or enhance recovery. However, some drugs may have a negative impact on neuroplasticity.

OBJECTIVES

This review examines currently used drugs that are believed to promote recovery from motor and cognitive disturbances associated with stroke.

METHODS

Literature regarding the properties, efficacy, safety, and dosing of drugs used to promote recovery after stroke was reviewed.

RESULTS

The data on pharmacotherapy are insufficient to support a claim of significantly improved rehabilitation outcomes. Moreover, a growing body of evidence indicates that some agents can impair functional reorganization and slow the recovery process. However, a few chemicals are reported to be beneficial for stroke rehabilitation. The most promising are noradrenergic and dopaminergic agents, as well as several growth factors; these should be the future focus of extensive randomized clinical trials.

CONCLUSIONS

Currently there is no drug with proven efficacy in enhancing poststroke recovery.

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.

Lacunar stroke

Lacunar infarcts or small subcortical infarcts result from occlusion of a single penetrating artery and account for one quarter of cerebral infarctions. Patients with a lacunar infarct usually present with a classical lacunar syndrome (pure motor hemiparesis, pure sensory syndrome, sensorimotor stroke, ataxic hemiparesis or dysarthria-clumsy hand) and, less frequently, an atypical lacunar syndrome. Hypertension and diabetes mellitus are major risk factors for lacunar stroke. Lacunar infarcts show a paradoxical clinical course with a favorable prognosis in the short term, characterized by a low early mortality and reduced functional disability on hospital discharge, but with an increased risk of death, stroke recurrence and dementia in the mid- and long term. Asymptomatic progression of small-vessel disease is a typical feature of the lacunar infarcts. For this reason, lacunar infarction should be regarded as a potentially severe condition rather than a relatively benign disorder and, therefore, lacunar stroke patients require adequate and rigorous management and follow-up. Antiplatelet drugs, careful blood pressure control, the use of statins and modification of lifestyle risk factors are key elements in secondary prevention after lacunar stroke.