Tag Archive: AVCi


Borderline-high blood pressure, known as prehypertension, was associated with an increased risk for stroke in a new meta-analysis that included more than 700,000 participants.

Although the increased risk was largely driven by high-range prehypertension, the risk was also increased in people with low-range prehypertension.

The study, published online in Neurology on March 12, was conducted by a Chinese group. The authors conclude that: “In this study, we had sufficient power to demonstrate that the risk of stroke is increased even in individuals with relatively mild BP elevations. Our findings reaffirm the importance of the definition of ‘prehypertension’ rather than being ‘normal’ for individuals with BP of 120–139/80–89 mm Hg.”

Senior author, Dingli Xu, MD, Southern Medical University in Guangzhou, China, said the findings had important clinical and public health implications. “Considering the high proportion of the population who have higher than normal blood pressure (30-50% of the population), successful treatment of this condition could prevent many strokes and make a major difference in public health,” he stated.

“Important” Study

Commenting for Medscape Medical News, Ralph L. Sacco, MD, University of Miami Miller School of Medicine, Florida, said, “This is an important study that adds to the accumulating evidence that borderline elevated blood pressure levels, also called prehypertension, significantly increases the risk of stroke.”

He stated: “This meta-analysis provides further evidence to physicians and patients that we need to take blood pressure seriously even at borderline levels. The first step is lifestyle modification with increasing physical activity, losing weight and eating healthy including reducing salt consumption. If these do not work or are unsuccessful, then medications may be warranted, particularly among those with elevated risk of stroke such as family history, diabetes, or other vascular conditions.”

Dr. Sacco noted that the study is timely because there has been some controversy regarding the recently released JNC8 recommendations that loosened the level of blood pressure defined as abnormal for those older than age 60 years and moved the level to a systolic pressure of 150 mm Hg.

“But in this study the effects of borderline elevations of blood pressure were significantly increased for those under 55 as much as those over 55,” Dr. Sacco pointed out. He added that the American Heart Association has defined ideal blood pressure as 120/80 mm Hg, and the study also confirms this as the optimal level.

In the Neurology paper, the authors explain that previous studies on the risk for stroke with prehypertension have shown mixed results. Therefore, a comprehensive meta-analysis of prospective cohort studies that examined the association between prehypertension and stroke, as well as the heterogeneity of risk within this category, may help to clarify this issue.

 

 

 

Côté R et al. Neurology 2014 Feb 4.

Long-term aspirin plus clopidogrel wasn’t better than aspirin alone.

In the previously published SPS3 trial, 3000 patients who experienced lacunar strokes during the previous 6 months were randomized to receive aspirin alone or aspirin plus clopidogrel. During several years of follow-up, dual antiplatelet therapy did not prevent recurrent stroke and increased risk for major hemorrhage and death (NEJM JW Neurol Aug 29 2012). Now, in a post hoc analysis from this study, researchers present data on the 838 patients who already had been taking prophylactic aspirin at the time of the lacunar stroke that qualified them for the trial.

Outcomes in this subgroup mirrored those of the larger study. During mean follow-up of 3.5 years, the annual stroke rate was 3% in both the aspirin monotherapy and dual antiplatelet therapy treatment groups. However, annual mortality was higher with dual therapy than with aspirin alone (2.9% vs. 1.4%; P=0.004), and gastrointestinal bleeding was more common with dual therapy.

COMMENT

In this analysis, aspirin plus clopidogrel was not more effective than aspirin alone for preventing subsequent strokes in patients with previous lacunar strokes that occurred during aspirin therapy. Note that SPS3 patients were randomized an average of 2.5 months after their index lacunar strokes. In contrast, in the recently published CHANCE trial (NEJM JW Neurol Jun 26 2013), short-term dual therapy was more effective than aspirin alone in patients with transient ischemic attack or minor stroke who were randomized within 24 hours; in that study, no distinction was made between lacunar strokes and other stroke subtypes.

Wang Y et al. N Engl J Med 2013 Jun 26.

Results of a study in China suggest that it might. 

To compare the effects of aspirin plus clopidogrel with aspirin alone in minor stroke or transient ischemic attack (TIA), more than 100 centers in China recruited a total of 5170 patients with a diagnosis of “high-risk” TIA or minor stroke within 24 hours of symptom onset. High-risk TIA was defined as a score of ≥4 on the ABCD2 scale, which is based on age, blood pressure, and other clinical variables. Minor stroke was defined as a score of ≤3 on the NIH Stroke Scale score.

All patients received aspirin (75–300 mg) on day 1 and 75 mg of aspirin through day 21. Those randomized to dual antiplatelet therapy received 300 mg of clopidogrel on day 1 and 75 mg on days 2 through 90, with aspirin placebo on days 22 through 90. Those randomized to aspirin alone continued on 75 mg of aspirin daily though day 90, with clopidogrel placebo on days 1 through 90.

During the 90-day follow-up period, there was a significant, 32% relative reduction in the rate of stroke with dual antiplatelet therapy (11.7% with aspirin alone, 8.2% with the combination; hazard ratio, 0.68) and a significant reduction in the combination of fatal or disabling stroke (HR, 0.75). Major extracranial or intracranial hemorrhages did not differ (0.3% in both groups).

COMMENT

Some treatments initially used for cardiac disease (e.g., thrombolysis and statins) have percolated into the prevention and treatment of stroke. Other treatments commonly used for cardiac disease, such as intravenous heparin, have not been proven useful for stroke.

What about dual antiplatelet therapy, which is effective for acute coronary syndromes? This study showed an impressive 32% relative and 3.5% absolute reduction in the rate of stroke with dual antiplatelet therapy. Asian populations differ from others with respect to the pathophysiology of stroke, such as greater frequency of intracranial stenosis. A North American study with a similar design is in progress (the POINT trial). If the second study confirms the benefits of dual antiplatelet therapy, another “cardiac” treatment could soon be applied to patients with cerebrovascular disease.

 

In patients with acute ischemic stroke, even small reductions in the time to thrombolytic therapy are associated with improved outcomes, according to a study in JAMA.

 

Using a national stroke registry, U.S. researchers examined outcomes among some 58,000 patients, at nearly 1400 hospitals, who received intravenous tissue plasminogen activator (tPA) within 4.5 hours after symptom onset. They found that with each 15-minute decrease in time to tPA therapy, patients were significantly less likely to die in the hospital or experience intracranial hemorrhage (odds ratio for each, 0.96). In addition, each 15-minute reduction was significantly associated with a greater likelihood to walk independently at discharge (OR, 1.04) and to be discharged home (OR, 1.03).

“These findings support intensive efforts to accelerate hospital presentation and thrombolytic treatment in patients with stroke,” the researchers conclude.

Time to Treatment With Intravenous Tissue Plasminogen Activator and Outcome From Acute Ischemic Stroke

Importance  Randomized clinical trials suggest the benefit of intravenous tissue-type plasminogen activator (tPA) in acute ischemic stroke is time dependent. However, modest sample sizes have limited characterization of the extent to which onset to treatment (OTT) time influences outcome; and the generalizability of findings to clinical practice is uncertain.

Objective  To evaluate the degree to which OTT time is associated with outcome among patients with acute ischemic stroke treated with intraveneous tPA.

Design, Setting, and Patients  Data were analyzed from 58 353 patients with acute ischemic stroke treated with tPA within 4.5 hours of symptom onset in 1395 hospitals participating in the Get With The Guidelines-Stroke Program, April 2003 to March 2012.

Main Outcomes and Measures  Relationship between OTT time and in-hospital mortality, symptomatic intracranial hemorrhage, ambulatory status at discharge, and discharge destination.

Results  Among the 58 353 tPA-treated patients, median age was 72 years, 50.3% were women, median OTT time was 144 minutes (interquartile range, 115-170), 9.3% (5404) had OTT time of 0 to 90 minutes, 77.2% (45 029) had OTT time of 91 to 180 minutes, and 13.6% (7920) had OTT time of 181 to 270 minutes. Median pretreatment National Institutes of Health Stroke Scale documented in 87.7% of patients was 11 (interquartile range, 6-17). Patient factors most strongly associated with shorter OTT included greater stroke severity (odds ratio [OR], 2.8; 95% CI, 2.5-3.1 per 5-point increase), arrival by ambulance (OR, 5.9; 95% CI, 4.5-7.3), and arrival during regular hours (OR, 4.6; 95% CI, 3.8-5.4). Overall, there were 5142 (8.8%) in-hospital deaths, 2873 (4.9%) patients had intracranial hemorrhage, 19 491 (33.4%) patients achieved independent ambulation at hospital discharge, and 22 541 (38.6%) patients were discharged to home. Faster OTT, in 15-minute increments, was associated with reduced in-hospital mortality (OR, 0.96; 95% CI, 0.95-0.98; P < .001), reduced symptomatic intracranial hemorrhage (OR, 0.96; 95% CI, 0.95-0.98; P < .001), increased achievement of independent ambulation at discharge (OR, 1.04; 95% CI, 1.03-1.05; P < .001), and increased discharge to home (OR, 1.03; 95% CI, 1.02-1.04; P < .001).

Conclusions and Relevance  In a registry representing US clinical practice, earlier thrombolytic treatment was associated with reduced mortality and symptomatic intracranial hemorrhage, and higher rates of independent ambulation at discharge and discharge to home following acute ischemic stroke. These findings support intensive efforts to accelerate hospital presentation and thrombolytic treatment in patients with stroke.