Stroke and the statistics of the aspirin/clopidogrel secondary prevention trials

Selecting an Optimal Antiplatelet Agent for Secondary Stroke Prevention

Four seminal randomized controlled trials (RCTs) have investigated aspirin, aspirin plus extended-release dipyridamole, and clopidogrel for the prevention of recurrent vascular events. Despite studying over 32,000 patients with stroke in these trials, the decision on which antiplatelet agent to select for secondary stroke prevention remains controversial. Attempts to translate the results of these RCTs into clinical practice are complicated by each trial's selection of participants and choice of primary outcome. Herein, we argue that by examining RCT results with participant selection limited to patients with ischemic stroke or TIA and by focusing on recurrent stroke as our outcome, we can use the standard epidemiology 2 × 2 table to assist in selecting an antiplatelet agent for secondary stroke prevention.

Critical Care Management of Acute Ischemic Stroke

OPINION STATEMENT

Ischemic stroke accounts for approximately 85% of all strokes. Although severe strokes constitute a minority of cases, they are associated with a majority of the subsequent disability and death. Reperfusion therapy with intravenous tissue plasminogen activator (tPA) and/or endovascular thrombectomy is a mainstay of acute stroke management. Intensive care management of stroke is focused on reducing complications of reperfusion, such as hemorrhagic transformation, and minimizing secondary brain injury, including brain edema and progressive stroke. Additionally, severe stroke patients frequently need ventilatory or hemodynamic support provided in an intensive care unit (ICU) setting. Here, we discuss the current medical and surgical ICU management aspects of acute ischemic stroke and identify areas where ongoing studies may reveal new treatments to improve neurological recovery.

Clinical efficacy and safety of traditional Chinese medicine combined with Western Medicine in patients with diabetic acute ischemic stroke

OBJECTIVE

To observe the clinical efficacy and safety of Traditional Chinese Medicine (TCM) combined with Western Medicine (WM) in patients with diabetic acute ischemic stroke.

METHODS

Ninety patients with diabetic acute ischemic stroke were randomly divided into a treatment group and a control group. The 45 patients in the treatment group were given standardized treatment with TCM combined with WM. They received corresponding oral Chinese decoctions three times daily, according to their TCM syndromes, along with basic western medical treatment. The 45 patients in the control group were given non-standardized treatment with TCM combined with WM. They received an oral Chinese decoction for promotion of blood circulation to inhibit hemostasis, regardless of their TCM syndromes, along with basic western medical treatment. The treatments lasted for 4 weeks. Scores were evaluated on the National Institutes of Health Stroke Scale (NIHSS) score, activity of daily life (ADL) scores, and TCM symptoms before treatment and 2 and 4 weeks after treatment.

RESULTS

Analysis of variance for repeated measurements showed that there were significant differences in NIHSS and ADL score before and after treatment in both groups (P < 0.05). There were also significant differences between the scores at 2 and 4 weeks after treatment. There were significant differences in TCM syndrome scores before and after treatment in both groups (P < 0.05). There were also significant differences between the scores at 2 and 4 weeks after treatment. The X2 test showed no statistically significant difference in the incidence of adverse reactions between the two groups (P > 0.05).

CONCLUSION

Standardized treatment was superior to non-standardized treatment for clinical efficacy of TCM combined with WM in patients with diabetic acute ischemic stroke, and the superiority was more obvious in improving neural dysfunction, ADL score, and TCM symptoms. The adverse reactions were similar in the two treatment groups.

Trends in Ambulatory Prescribing of Antiplatelet Therapy among US Ischemic Stroke Patients: 2000-2007

Objective. Study objectives were to assess temporal trends and identify patient- and practice-level predictors of the prescription of antiplatelet medications in a national sample of ischemic stroke (IS) patients seeking ambulatory care. Methods. IS-related outpatient visits by adults were identified using the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey for the years 2000-2007. We assessed prescribing of antiplatelet medications using the generic drug code and drug entry codes in these data. Temporal trends in antiplatelet prescribing were assessed using the Cochran-Mantel-Haenszel test for trend. Results. We identified 9.5 million IS-related ambulatory visits. Antiplatelet medications were prescribed at 35.5% of visits. Physician office prescribing of the clopidogrel-aspirin combination increased significantly from 0.5% in 2000 to 22.0% in 2007 (P = 0.05), whereas prescribing of aspirin decreased from 17.9% to 7.0% (P = 0.50) during the same period. Conclusion. We observed a continued increase in prescription of the aspirin-clopidogrel combination from 2000 to 2007. Clinical trial evidence suggests that the aspirin-clopidogrel combination does not provide any additional benefit compared with clopidogrel alone; however, our study findings indicate that even with lack of adequate clinical evidence physician prescribing of this combination has increased in real-world community settings.

Revaluation of clopidogrel: let the data speak for themselves

Clopidogrel was believed to be superior to aspirin by the well-known CAPRIE trial. However, no other large clinical trials demonstrated the same results, but all focused on the combination use of clopidogrel with aspirin, and combination therapy in CREDO was called the "Emperor's New Clothes". However, no one overturned the results of these clinical trials by quantitatively analyzing them. We reviewed ten large-scale clinical trials about clopidogrel. On the basis of results of CAPRIE, CREDO and CHARISMA trials, we re-estimated their minimal sample sizes and their powers by three well-established statistical methodologies. From the results of CAPRIE, we inferred that the minimal sample size should be 85 086 or 84 968 but its power was only 30.70%. A huge gap existed. The same was also true of CREDO and CHARISMA trials. Moreover, in CAPRIE trial, 0 was included in the 95% confidence interval and 1 was included in the 95% confidence interval for the relative risk. There were some paradoxical data in CAPRIE trial. We are led to conclude that the results in CAPRIE, CREDO, and from the subgroup analysis in CHARISMA trials were questionable. These results failed to demonstrate that clopidogrel was superior to aspirin or that clopidogrel used in combination with aspirin was better than aspirin alone. The cost-effectiveness analyses by some previous studies were not reliable.

Diabetes mellitus and cerebrovascular disease: which are the actual data?

Cerebrovascular disease (CeVD) represents a major cause of morbidity and mortality worldwide. Diabetes mellitus (DM) represents an independent risk factor for CeVD. The aim of the present review is to describe the epidemiology of CeVD in patients with DM and to explain how DM and diabetic autonomic neuropathy can increase the risk of CeVD. The prevention and management of CeVD in the diabetic population are also analyzed.

Review: Recurrent stroke: where do we stand with the secondary prevention of noncardioembolic ischaemic strokes?

Strokes recur in 6—20% of the patients, most commonly within the first year; after a TIA or minor stroke; most recurrences will occur within the first 90 days. Our ability to identify patients at high risk is poor and most recurrent strokes cannot be explained by traditional risk factors. In 30—45% of the cases the second stroke will be of a different subtype. Moreover, patients are faced with other risks, like cardiac events and cognitive decline. With the population aging, the need for timely and effective secondary prevention strategies is more pressing than ever. This paper summarizes recent advances in pharmacological secondary prevention after a non-cardioembolic ischaemic stroke, and highlights critical questions still in need of answers.