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Objective:To compare the impact of intensive blood pressure (BP) lowering right after intracerebral hemorrhage (ICH) on clinical and hematoma outcomes among patients from different geographic locations, we performed a prespecified sub-analysis of the randomized, multi-national, two-group, open-label trial to determine the efficacy of rapidly lowering BP in hyperacute ICH (ATACH-2), involving 537 patients from East Asia and 463 recruited outside of Asia.Methods:Eligible patients were randomly assigned to a systolic BP (SBP) target of 110-139 mmHg (intensive treatment) or 140-179 mmHg (standard treatment). Pre-defined outcomes were: poor functional outcome (modified Rankin Scale score of 4-6 at 90 days), death within 90 days, hematoma expansion at 24 hours; and cardio-renal adverse events within 7 days.Results:Poor functional outcomes (32.0% versus 45.9%), death (1.9% versus 13.3%), and cardio-renal adverse events (3.9% versus 11.2%) occurred significantly less in patients from Asia than those outside of Asia. The treatment-by-cohort interaction was not significant for any outcomes. Only patients from Asia showed a lower incidence of hematoma expansion with intensive treatment (adjusted RR 0.56, 95% CI 0.38-0.83). Both Asian (3.53, 1.28-9.64) and non-Asian cohorts (1.71, 1.00-2.93) showed a higher incidence of cardio-renal adverse events with intensive treatment.Conclusions:Poor functional outcomes and death 90 days after ICH were less common in patients from East Asia than those outside of Asia. Hematoma expansion, a potential predictor for poor clinical outcome, was attenuated by intensive BP lowering only in the Asian cohort.Clinicaltrials.gov identifierNCT01176565.Classification of evidence:This study provides Class II evidence that, for patients from East Asia with intracerebral hemorrhage, intensive blood pressure lowering significantly reduces the risk of hematoma expansion.

Stroke incidence and mortality are disproportionately higher among African Americans than among whites.To describe the recurrent stroke characteristics and determine the predictability of known vascular risk factors for stroke recurrence in African Americans.The authors followed 1,809 African Americans in the African-American Antiplatelet Stroke Prevention Study with recent noncardioembolic ischemic stroke for recurrent stroke, recurrent stroke subtype, and disability.Of the subjects, 10.6% experienced a recurrent stroke during follow-up. The mean interval between eligibility and recurrent stroke was 325 days (median 287 days, SD = 224 days). Stroke recurrence resulted in an average 1.5-point increase in the National Institute of Health Stroke Scale (p0.001) and a 3.5-point decrease in modified Barthel Index (p0.001). Of previously nondisabled subjects, 48% became disabled or died after stroke recurrence (p0.0001). Longitudinal analysis resulted in a hazard for recurrent stroke for each 10-mm Hg increase in systolic blood pressure of 1.103 (95% CI: 1.031 to 1.179, p = 0.004), pulse pressure 1.123 (95% CI: 1.041 to 1.213, p = 0.003), and mean arterial pressure 1.123 (95% CI: 1.001 to 1.260, p = 0.048). Multivariate analysis revealed increases in the recurrent stroke hazard for increases in baseline Glasgow Outcome Score (1.449, 95% CI: 1.071 to 1.961, p = 0.016) and increases in longitudinal pulse pressure (1.009, 95% CI: 1.001 to 1.017, p = 0.029).Recurrent stroke leads to disability and disability predicts recurrent stroke. Hypertension is the most predictive modifiable stroke risk factor.

Objective: To review the risk of MS exacerbations after infectious episodes potentially preventable by vaccination, and the risks and benefits of immunizing patients with MS. Methods: The authors searched MEDLINE (1966 to January 2001; U.S. National Library of Medicine, Bethesda, MD), HealthSTAR, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) database (Cinahl Information Systems, Glendale, CA) for English-language articles. Each study was summarized and rated for quality of evidence. Then feasible data were pooled and analyzed in meta-analysis. Results: The risk of contracting common infectious diseases in patients with MS is not well established. There is strong evidence for an increased risk of MS exacerbations during weeks around an infectious episode. There is strong evidence against an increased risk of MS exacerbation after influenza immunization. There is no evidence that hepatitis B, varicella, tetanus, or Bacille Calmette–Guerin vaccines increase the risk of MS exacerbations. Insufficient evidence was found for other vaccines. Conclusions: Evidence supports 1) strategies to minimize the risk of acquiring infectious diseases that may trigger exacerbations of MS; and 2) the safety of using influenza, hepatitis B, varicella, tetanus, and Bacille Calmette–Guerin (BCG) vaccines in patients with MS.

Objective: To review the use of transcranial Doppler ultrasonography (TCD) and transcranial color-coded sonography (TCCS) for diagnosis. Methods: The authors searched the literature for evidence of 1) if TCD provides useful information in specific clinical settings; 2) if using this information improves clinical decision making, as reflected by improved patient outcomes; and 3) if TCD is preferable to other diagnostic tests in these clinical situations. Results: TCD is of established value in the screening of children aged 2 to 16 years with sickle cell disease for stroke risk (Type A, Class I) and the detection and monitoring of angiographic vasospasm after spontaneous subarachnoid hemorrhage (Type A, Class I to II). TCD and TCCS provide important information and may have value for detection of intracranial steno-occlusive disease (Type B, Class II to III), vasomotor reactivity testing (Type B, Class II to III), detection of cerebral circulatory arrest/brain death (Type A, Class II), monitoring carotid endarterectomy (Type B, Class II to III), monitoring cerebral thrombolysis (Type B, Class II to III), and monitoring coronary artery bypass graft operations (Type B to C, Class II to III). Contrast-enhanced TCD/TCCS can also provide useful information in right-to-left cardiac/extracardiac shunts (Type A, Class II), intracranial occlusive disease (Type B, Class II to IV), and hemorrhagic cerebrovascular disease (Type B, Class II to IV), although other techniques may be preferable in these settings.

Although hyperglycemia has been shown to consistently exacerbate ischemia brain injury following global or diffuse cerebral ischemia, the effect of hyperglycemia in unilateral focal cerebral ischemia remains controversial. Recent advances in thrombolytic therapy have enhanced the clinical significance of postischemic reperfusion. We studied the effect of plasma glucose on ischemic brain injury in a newly developed focal cerebral ischemia-reperfusion model. Rats allowed free access to food until ischemic insult developed intra- and postischemic hyperglycemia and cortical infarction. Rats fasted for 24 hours had blunted hyperglycemic responses. Infarct volumes were correspondingly smaller. The protective effect of fasting was partially abolished by glucose loading during ischemia to induce intra-ischemic hyperglycemia. Glucose loading immediately or 3 hours after focal cerebral ischemia did not significantly alter the protective effect of fasting. Insulin treatment in fed rats before ischemia also reduced hyperglycemic responses and infarct volume. Timing of insulin treatment was also critical in the reduction of ischemic injury. These findings indicate that plasma glucose during the period of ischemia is an important determinant of brain injury in focal cerebral ischemia-reperfusion and there is a therapeutic window for normalization of plasma glucose to be efficacious.

Our understanding of the biochemistry and biologic actions of AA metabolites has been greatly expanded in recent years. The discoveries of TXA2, PGI2, and LTs have fostered new concepts of the pathophysiology of cerebral ischemia. New approaches to treatment of ischemia include seeking an optimal dose of aspirin, developing drugs that selectively inhibit or antagonize TXA2 or LTs, and administering PGI2 or its analogues. Altering the dietary content of essential fatty acids for prophylaxis is also being studied. Though the results of this thrust are still preliminary, the exploration of these therapeutic strategies in cerebrovascular disorders based on further understanding of the pathophysiologic roles of TXA2, PGI2, LTs and probably other AA metabolites is anticipated with some optimism.

Three patients with brainstem tumors had orthostatic hypotension as the major presenting manifestation. Two patients had primary tumors that involved the dorsal medulla, pons, and rostra1 spinal cord; one was a malignant astrocytoma and the other a hemangioblastoma. The third patient had an oat cell carcinoma of the lung with subependymal spread to the medulla, pons, hypothalamus, and thalamus. Evaluation of baroreceptor function in the patient with the malignant astrocytoma showed a defect in the efferent sympathetic limb of the baroreceptor reflex arc.

We measured levels of thromboxane B2 and 6-keto-PGF1 alpha in rabbit spinal cord and cat CSF after impact injury to spinal cord. Rabbit tissue thromboxane B2 levels increased more than 6-keto-PGF1 alpha. In cat, CSF thromboxane B2 was higher the first hour postinjury; CSF 6-keto-PGF1 alpha also increased, but less so. These results imply activation of arachidonic acid metabolism. The relatively greater increase of thromboxane B2 suggests that thromboxane-prostacyclin imbalance may contribute to post-traumatic ischemia.

Hypertensive intracerebral hemorrhage (HICH) is generally considered to be a monophasic event. Enlargement of the initial hematoma after several hours or days has rarely been documented. We describe the clinical and CT findings in 8 patients (5 men, 3 women, aged 39 to 68 years) with continued bleeding or rebleeding during the acute phase of HICH. The thalamus was the most frequent site of hemorrhage (6/8). The neurologic status deteriorated in all: 6 within 24 hours, and 2 after 5 and 7 days. Persistent hypertension was common (6/8) prior to extension of the hemorrhage. The 2nd CT revealed an obvious increase in hematoma size in all cases. Four patients died and 4 survived with severe neurologic disability. These serial studies indicate that active bleeding or rebleeding can occur in HICH and suggests that the risk is particularly high with thalamic hemorrhage. We conclude that meticulous control of hypertension after HICH may be justified in selected patients.

Three degrees of focal ischemic infarction in the rat were created in the cerebral cortex supplied by the right middle cerebral artery, by ligation of the right middle cerebral artery and the right common carotid artery and temporary clip compression of the left common carotid artery, in succession. The postischemic accumulation of calcium in cerebral cortex of the right middle cerebral artery territory, determined by atomic absorption spectrometry, correlated with the infarct volume. The results are consistent with the hypothesis that calcium has role as a mediator in the pathogenesis of cerebral infarction.