Time of hospital presentation in patients with acute stroke.

BACKGROUND: Stroke is a leading cause of death and disability in the United States. Although new treatments are being studied, most must be given early in the course of stroke to be effective. This study was performed to identify factors associated with early hospital arrival in patients with stroke. METHODS: As part of the National Institute of Neurologic Disorders and Stroke Tissue-Type Plasminogen Activator Pilot Study, information from patients, patients' families, or, most commonly, the medical record was gathered on all patients presenting to the hospital within 24 hours of the onset of stroke. A total of 14 hospitals participated. Three were university hospitals, and 11 were community hospitals with and without university affiliation. The main outcome measure was the time from stroke onset to hospital arrival. RESULTS: Of 2099 patients screened, adequate time data were available in 1159. Thirty-nine percent presented to the hospital 90 minutes or less after symptom onset and 59% within 3 hours. Early hospital arrival after stroke was greatly influenced by the type of first medical contact and, to a lesser degree, by the patient's location at the time of the stroke and the time of the day at which the stroke occurred. Hospital arrival was fastest in patients using 911 as their first medical contact (mean, 155 minutes; median, 84 minutes) vs their personal physician (mean, 379 minutes; median, 270 minutes; P < .0001) or a study hospital (mean, 333 minutes; median, 212 minutes; P < .0001). Time from symptom onset to arrival was longer for patients having the stroke at night compared with patients having a stroke in the morning (P < .05), in the afternoon (P < .01), or in the evening (P < .0001). Time to hospital arrival was significantly longer for patients having the stroke at home than for patients having the stroke at work (P < .01) or in an unknown place (P < .05). Gender, age, race, and presence of brain hemorrhage had no significant effect. CONCLUSIONS: As many as 50% of patients with stroke arrive at the hospital within 3 hours of symptom onset. Our data indicate that strategies to increase the use of 911 systems may have a high yield with regard to recruitment into urgent treatment protocols for stroke.

Finding the most powerful measures of the effectiveness of tissue plasminogen activator in the NINDS tPA stroke trial.

BACKGROUND AND PURPOSE: We sought to identify the most powerful binary measures of the treatment effect of tissue plasminogen activator (tPA) in the National Institute of Neurological Disorders and Stroke (NINDS) rTPA Stroke Trial. METHODS: Using the Classification and Regression Tree (CART) algorithm, we evaluated binary cut points and combination of binary cut points with the 4 clinical scales and head CT imaging measures in the NINDS tPA Stroke Trial at 4 times after treatment: 2 hours, 24 hours, 7 to 10 days, and 3 months. The first analysis focused on detecting evidence of "early activity" of tPA with the use of outcome measures derived from the 2-hour and 24-hour clinical and radiographic measures. The second analysis focused on longer-term outcome and "efficacy" and used outcome measures derived from 7- to 10-day and 3-month measures. After identifying the cut points with the ability to classify patients into the tPA and placebo groups using part I data from the trial, we then used data from part II of the trial to validate the results. RESULTS: Of the 5 most powerful outcome measures for early activity of tPA, 4 involved the National Institutes of Health Stroke Scale (NIHSS) score at 24 hours or changes in the NIHSS score from baseline to 24 hours. The best overall single outcome measure was an NIHSS score

Circadian variation in onset of acute ischemic stroke.

A circadian pattern for the onset of myocardial and cerebral infarction has been identified. To evaluate this phenomenon further, we analyzed prospectively collected data from 151 patients with acute ischemic stroke. The number of strokes per 6-hour period were the following: midnight to 6 AM, 20 (13%); 6 AM to noon, 86 (57%); noon to 6 PM, 21 (14%); and 6 PM to midnight, 24 (16%). This pattern was not affected by previous use of aspirin. The most frequent time of onset was 6 AM to noon for all subgroups of ischemic stroke: small artery, 71%; cardioembolic, 62%; large artery atherothrombotic, 57%; large artery atheroembolic, 46%; and "other" or unknown cause, 40%. We also investigated the time between awakening and stroke onset in 145 patients and found that 24% of ischemic strokes occurred within the first hour after awakening. Our data demonstrate that an early morning peak exists for all subtypes of stroke. Our data also suggest that the most critical period is the first hour after awakening.

Adrenoleukodystrophy (ALD): clinical and CT features of a childhood variant.

A variant of childhood adrenoleukodystrophy (ALD) affected two male cousins. The characteristic features include a progressive frontal lobe syndrome, frontal pole CT hypodensity, abnormal levels of plasma very-long-chain fatty acids, and a family history consistent with X-linked inheritance.

A dose escalation study of ORG 10172 (low molecular weight heparinoid) in stroke.

An intravenous infusion of a low molecular weight heparinoid, with a reduced risk of hemorrhage, may be an alternative to heparin in the management of acute ischemic stroke. To evaluate this hypothesis, we studied the safety of the heparinoid, ORG 10172, in a dose-escalation study in 26 patients. The drug was administered as a loading bolus followed by a 7-day infusion in five rates with target anti-factor Xa levels from 0.2 to 1.0 U/ml. The drug was well tolerated; no major bleeding complications or thrombocytopenia occurred. There were no deaths or hemorrhagic transformation of cerebral infarctions. The results indicate that ORG 10172 at doses to achieve a level of 1.0 U/ml or less may be used safely in management of acute cerebral infarction.

Thrombolysis in acute ischemic stroke: controlled trials and clinical experience.

Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) is approved in the United States for treatment of acute ischemic stroke. Approval was granted after a large, randomized, placebo-controlled study by the National Institute of Neurological Disorders and Stroke (NINDS) showed a significant improvement in 3-month outcomes with rtPA despite a significant risk for symptomatic hemorrhage. Two other trials, the first and second European Cooperative Acute Stroke Study (ECASS I and II), have shown comparable results, but neither was statistically positive for the predefined primary end point. An analysis of the risk/benefit profile of rtPA therapy based on the results of these three trials indicates that the treatment is effective and, when administered within 3 hours of symptom onset at a dose of 0.9 mg/kg, the benefits by far outweigh the risks for eligible patients. Even with the 6-hour time window of the two ECASS trials, a combined analysis of the three studies shows the number of disabled or dead patients to be significantly reduced. Preliminary data collected on the use of rtPA outside of clinical trials in the United States and Europe suggest that, when rtPA is used according to the trial protocol, the risks and benefits are similar to those observed in clinical trials. However, even within the United States, rtPA is underutilized. The most substantial treatment barrier is the narrow time window, which may be expanded if long-term experience shows that this is possible. Most stroke patients arrive at the hospital too late to be eligible for screening and treatment. Education of the public and physicians may help to overcome this difficulty.

Cost-effectiveness of tissue plasminogen activator for acute ischemic stroke. NINDS rt-PA Stroke Study Group.

Tissue plasminogen activator (tPA) has been shown to improve 3-month outcome in stroke patients treated within 3 hours of symptom onset. The costs associated with this new treatment will be a factor in determining the extent of its utilization. Data from the NINDS rt-PA Stroke Trial and the medical literature were used to estimate the health and economic outcomes associated with using tPA in acute stroke patients. A Markov model was developed to estimate the costs per 1,000 patients eligible for treatment with tPA compared with the costs per 1,000 untreated patients. One-way and multiway sensitivity analyses (using Monte Carlo simulation) were performed to estimate the overall uncertainty of the model results. In the NINDS rt-PA Stroke Trial, the average length of stay was significantly shorter in tPA-treated patients than in placebo-treated patients (10.9 versus 12.4 days; p = 0.02) and more tPA patients were discharged to home than to inpatient rehabilitation or a nursing home (48% versus 36%; p = 0.002). The Markov model estimated an increase in hospitalization costs of $1.7 million and a decrease in rehabilitation costs of $1.4 million and nursing home cost of $4.8 million per 1,000 eligible treated patients for a health care system that includes acute through long-term care facilities. Multiway sensitivity analysis revealed a greater than 90% probability of cost savings. The estimated impact on long-term health outcomes was 564 (3 to 850) quality-adjusted life-years saved over 30 years of the model per 1,000 patients. Treating acute ischemic stroke patients with tPA within 3 hours of symptom onset improves functional outcome at 3 months and is likely to result in a net cost savings to the health care system.

Early stroke treatment associated with better outcome: the NINDS rt-PA stroke study.

BACKGROUND: The National Institute of Neurological Disorders and Stroke (NINDS) rt-PA Stroke Study showed a similar percentage of intracranial hemorrhage and good outcome in patients 3 months after stroke treatment given 0 to 90 minutes and 91 to 180 minutes after stroke onset. At 24 hours after stroke onset more patients treated 0 to 90 compared to 91 to 180 minutes after stroke onset had improved by four or more points on the NIH Stroke Scale (NIHSS). The authors performed further analyses to characterize the relationship of onset-to-treatment time (OTT) to outcome at 3 months, early improvement at 24 hours, and intracranial hemorrhage within 36 hours. METHODS: Univariate analyses identified potentially confounding variables associated with OTT that could mask an OTT-treatment interaction. Tests for OTT-treatment interactions adjusting for potential masking confounders were performed. An OTT-treatment interaction was considered significant if p < or = 0.10, implying that treatment effectiveness was related to OTT. RESULTS: For 24-hour improvement, there were no masking confounders identified and there was an OTT-treatment interaction (p = 0.08). For 3-month favorable outcome, the NIHSS met criteria for a masking confounder. After adjusting for NIHSS as a covariate, an OTT-treatment interaction was detected (p = 0.09): the adjusted OR (95% CI) for a favorable 3-month outcome associated with recombinant tissue-type plasminogen activator (rt-PA) was 2.11 (1.33 to 3.35) in the 0 to 90 minute stratum and 1.69 (1.09 to 2.62) in the 91 to 180 minute stratum. In the group treated with rt-PA, after adjusting for baseline NIHSS, an effect of OTT on the occurrence of intracranial hemorrhage was not detected. CONCLUSIONS: If the NINDS rt-PA Stroke Trial treatment protocol is followed, this analysis suggests that patients treated 0 to 90 minutes from stroke onset with rt-PA have an increased odds of improvement at 24 hours and favorable 3-month outcome compared to patients treated later than 90 minutes. No effect of OTT on intracranial hemorrhage was detected within the group treated with rt-PA, possibly due to low power.

Dose-escalation study of intravenous nicardipine in patients with aneurysmal subarachnoid hemorrhage.

A dose-escalation study of the calcium ion entry blocking drug nicardipine was performed using large dose infusions in 67 patients with recent aneurysmal subarachnoid hemorrhage (SAH). A safe, potentially therapeutic dose of the drug was determined. Patients admitted within 7 days of SAH from a documented cerebral aneurysm were entered into the study if no spasm was present on the initial angiogram. Nicardipine was administered as a continuous intravenous infusion throughout the 14-day period after SAH, regardless of the timing of surgery. To determine the safest possible dose, nicardipine was administered at seven dose levels from 0.01 to 0.15 mg/kg/hr. The total daily doses ranged from 27.7 mg to 375.0 mg. A follow-up angiogram was carried out on all 67 patients 7 to 10 days after SAH. Computerized tomography and neurological examinations were used to determine the presence of cerebral infarction. No major adverse effects, unexpected reactions, or permanent sequelae could be attributed to nicardipine. A decline in blood pressure was noted following administration of the drug. This occurred more frequently among patients given the largest dose but did not produce clinical problems or require discontinuation of the drug. Favorable outcomes were noted in 52 patients (78%). Vasospasm was found by arteriography in 31 patients (46%). A dose-related trend was noted: only eight (24%) of 33 patients treated at the highest dose level (approximately 10 mg/hr) developed arteriographic evidence of vasospasm. Symptomatic vasospasm was diagnosed in only two (6%) of 33 patients treated with this dose. Of the 34 patients receiving the lower dose levels, angiographic spasm was observed in 68% and symptomatic vasospasm in 27%. No deaths due to vasospasm occurred. Nicardipine appears to prevent both vasospasm and cerebral ischemia after SAH. A multicenter randomized double-blind trial to test this hypothesis is planned.

Urgent therapy for acute stroke. Effects of a stroke trial on untreated patients.

BACKGROUND AND PURPOSE: As part of the recruitment efforts for the National Institutes of Health Tissue Plasminogen Activator Pilot Study, public education and awareness campaigns were conducted to encourage early hospital arrival. We evaluated the change in arrival times during the course of the study for all stroke patients, including those who were not entered into study. METHODS: Data were gathered on all patients presenting within 24 hours of stroke onset to all of the study hospitals. Coincident with the start of the study, educational and promotional programs, which stressed signs and symptoms of stroke and the need to call 911, were presented to physicians, paramedical personnel, and the public. The study was divided into four quartiles to analyze differences in time to hospital arrival and use of 911. RESULTS: Of 2099 patients screened, time data were available on 1116. During the course of the study, the mean time from symptom onset to hospital arrival declined significantly (3.2 hours versus 1.5 hours). Patients arrived for treatment sooner at community hospitals than at university/teaching hospitals. The use of 911 increased from 39% in the first quartile of the study to 60% in the fourth quartile. This was a consistent finding in all study sites. Increased use of 911 was seen almost exclusively in patients with nonhemorrhagic stroke. CONCLUSIONS: Times from stroke onset to hospital arrival decreased significantly during the course of the National Institutes of Health Tissue Plasminogen Activator Pilot Study. Significantly increased use of 911 was the likely major explanation for the shortened arrival times. The decrease in arrival times may be a consequence of the public and professional education programs conducted at all study sites.

Circadian rhythmicity of stroke onset. Intracerebral and subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Our purpose was to describe and further understand the determinants of the time of onset of parenchymatous intracerebral hemorrhage and subarachnoid hemorrhage in patients enrolled in the Stroke Data Bank. METHODS: We analyzed the observed times of onset of intracerebral hemorrhage (n = 237 patients) and subarachnoid hemorrhage (n = 243 patients) compared with expected times of onset if the probability of onset was constant across all time intervals. We also analyzed the role of clinical features (if any) in explaining the findings. RESULTS: For intracerebral hemorrhage, 52.5% of patients reported onset times between 0600 hours and 1400 hours, with peak onset between 1000 and 1200 hours (chi 2 = 62.94, df = 11, p less than 0.001). Patients with subarachnoid hemorrhage were more likely to lack a history of hypertension compared with patients who had intracerebral hemorrhage (chi 2 = 23.3, df = 1, p less than 0.001). Patients with subarachnoid hemorrhage were more likely to have more uniform onset time throughout the day (chi 2 = 12.92, df = 7, p = 0.074). However, subarachnoid hemorrhage patients with a history of hypertension were more likely to have peak onset times in mid-to-late morning compared with patients without such a history (chi 2 = 35.25, df = 10, p less than 0.001). The nonuniformity of onset times for intracerebral hemorrhage persisted even if patients with unknown onset times were treated as through their onset times were randomly distributed between 0000 and 0800 hours. Seasonal periodicity and the relation between initial systolic or diastolic blood pressure and time of onset for either type of hemorrhage were not observed. CONCLUSIONS: Our data suggest that the time of onset for both intracerebral hemorrhage and subarachnoid hemorrhage patients with a history of hypertension is similar to the diurnal variation in blood pressure.

Measurements of acute cerebral infarction: a clinical examination scale.

We designed a 15-item neurologic examination stroke scale for use in acute stroke therapy trials. In a study of 24 stroke patients, interrater reliability for the scale was found to be high (mean kappa = 0.69), and test-retest reliability was also high (mean kappa = 0.66-0.77). Test-retest reliability did not differ significantly among a neurologist, a neurology house officer, a neurology nurse, or an emergency department nurse. The stroke scale validity was assessed by comparing the scale scores obtained prospectively on 65 acute stroke patients to the patients' infarction size as measured by computed tomography scan at 1 week and to the patients' clinical outcome as determined at 3 months. These correlations (scale-lesion size r = 0.68, scale-outcome r = 0.79) suggested acceptable examination and scale validity. Of the 15 test items, the most interrater reliable item (pupillary response) had low validity. Less reliable items such as upper or lower extremity motor function were more valid. We discuss methods for improving the reliability and validity of brief examination scales to be used in stroke therapy trials.

Measurements of acute cerebral infarction: lesion size by computed tomography.

As part of a prospective therapy study of 65 patients with acute, nonhemorrhagic, cerebral infarction, computed tomographic scans of the head were obtained at admission, 7-10 days, and 3 months. The scans were analyzed for the presence, site, size, and volume measurement of the infarction. At 7-10 days, the mean infarction volume as measured by computed tomography was 55 cm3 or about 4 x 4 x 3.5 cm (range = 0-507 cm3). At 3 months, the mean infarction volume decreased by 25% to 41 cm3. For the 26 scans showing infarction at the time of admission, the mean lesion volume was 33 cm3 at admission, 51 cm3 at 7-10 days, and 49 cm3 at 3 months. With lesion size at 7-10 days expressed as percentage of total brain volume, the mean infarction size was only 5%. Of the 49 patients with lesions revealed by computed tomography at 7-10 days, 20 had an infarction of 1% or less of total brain volume, while only six had an infarction of 20% or more of total brain volume. The lesion volumes as measured by the 7-10-day computed tomography correlated with the neurologic examination scores on admission (Spearman's rank-order correlation = 0.78) and with the scores at 1 week (Spearman's rank-order correlation = 0.79).

The investigational use of tPA for stroke.

Stroke therapy trials have historically allowed for late patient entry (ie, within 24 to 48 hours from stroke onset) despite evidence suggesting the importance of early intervention. Experimental studies of cerebral infarction suggest treatment may be most effective when begun within three hours and may be only marginally effective when begun after 12 hours. Lysis of an acute intra-arterial thrombus in the setting of thrombolytic therapy is also time dependent. We describe an ongoing dose-escalation study of tissue plasminogen activator (tPA) as ultra-early therapy for cerebral infarction. The protocol requires that hemorrhage be ruled out by computed tomography scan of the brain prior to tPA infusion, and the infusion must begin within 90 minutes of symptom onset. The two primary goals of the study are to assess safety and potential efficacy. Preliminary results from the study and the future of ultra-early stroke intervention are discussed.

High-dose intravenous naloxone for the treatment of acute ischemic stroke.

To evaluate the safety and possible efficacy of high-dose naloxone for the treatment of acute cerebral ischemia, 38 patients received a loading dose of 160 mg/m2 over 15 minutes followed by a 24-hour infusion at the rate of 80 mg/m2/hr. Nausea and/or vomiting were common side effects. Naloxone was discontinued in seven patients (because of hypotension in one, bradycardia and hypotension in two, myoclonus in one, focal seizures in two, and hypertension in one); all seven patients responded to treatment and no permanent sequelae to naloxone were noted. Twelve of the 38 patients showed early neurologic improvement (by completion of the naloxone loading dose). However, there was no correlation between such a loading dose response and clinical outcome at 3 months. Our experience suggests that naloxone is safe at the dose used, but data for efficacy are inconclusive.

Large-dose infusions of heparinoid ORG 10172 in ischemic stroke.

We evaluated the safety and possible efficacy of large doses of the heparinoid ORG 10172 in 57 patients with acute or progressing ischemic stroke. Patients received a loading bolus of the drug followed by a maintenance intravenous infusion for 7 days. The plasma level of ORG 10172 was monitored by the degree of inhibition of coagulation factor Xa. In general, the drug was well tolerated and few hemorrhagic complications occurred. Two patients with large cardioembolic hemispheric strokes had intracranial hemorrhagic complications. Most patients improved during treatment. By 3 months after the stroke, 37 patients (65%) had a favorable outcome (minimal or no residual disability). This study suggests that high-dose intravenous infusions of ORG 10172 can be safely given to patients with acute ischemic stroke.

Factors related to intracranial hematoma formation in patients receiving tissue-type plasminogen activator for acute ischemic stroke.

BACKGROUND AND PURPOSE: Several studies are currently evaluating tissue-type plasminogen activator (TPA) as a potential therapy in acute ischemic stroke. The possibility of inducing intracranial hematomas, however, introduces an important concern into ultimate evaluation of risk and benefit. This retrospective analysis sought to identify factors associated with intracranial hematoma formation in a pilot phase 1 study of TPA for stroke. METHODS: Ninety-four patients received TPA within 3 hours of the onset of an acute ischemic stroke. Five of these patients developed a symptomatic intracerebral hematoma: 3 of 74 (4%) among patients treated within 90 minutes of stroke onset and 2 of 20 (10%) among those treated at 91 to 180 minutes. Three of the 5 died within 2 weeks. The analysis investigated associations between clinical factors and intracerebral hematomas. RESULTS: Factors significantly related to the development of an intracerebral hematoma were TPA dose and diastolic hypertension. Intracerebral hematomas developed in 4 (18%) of 22 patients given a TPA dose of at least 0.90 mg/kg versus only 1 hematoma in the remaining 72 patients (1%; P < .02, Fisher's exact test). Four (18%) of 22 patients who had initial diastolic blood pressures of at least 100 mm Hg suffered an intracerebral hematoma versus only 1 (1%) of 72 patients (P < .02) with lower initial diastolic pressures. CONCLUSIONS: Since the study was not designed to test specific safety hypotheses, results must not be overinterpreted. Nonetheless, these data emphasize the need for caution in both patient and dose selection for further studies of thrombolytic agents in stroke.