8:30 a.m. Abstracts 34 – Results due from trial of magnesium in treating stroke. Pilot studies suggested that IV administration of magnesium salts after acute stroke may reduce death and improve functional outcome. Now, Scottish investigators are ready to present final results of IMAGES (Intravenous Magnesium Efficacy in Stroke) Trial, "the largest acute neuroprotective trial undertaken to date." In this randomized, double-blind, placebo controlled trial, 2,591 patients at 125 centers received either magnesium sulfate or placebo for 24 hours, within 12 hours of stroke onset. In 38 percent of patients, treatment began within 6 hours of onset. Patients' average age was 70, 53 percent male. Patient scores on two tests of neurological function were determined in clinic visits (996 patients) or telephone calls (1,448 patients). CT scans blinded to type of treatment were read at a central location. Results will include modified Rankin scale and Barthel index scores at 90 days for all patients receiving study medication and for the subgroup treated within 6 hours.
4 p.m. Abstract P206 – Patient education best route to improving stroke treatment rate. Healthcare providers are accelerating their response and treatment rates for patients with ischemic stroke, but the public itself offers the best chance for further improvement, a California study found. As part of the Paul Coverdell Acute Stroke Pilot Registry in California, researchers studied patients with suspected stroke in 11 hospitals. Of the 375 patients diagnosed with acute ischemic stroke, only 22, or 6 percent, had received clot-busting drugs or mechanical removal of the clot within three hours of symptoms onset. A specific time of stroke onset couldn't be determined in 50 percent of patients. Researchers calculated that faster emergency responses and "perfect" in-hospital care could have raised treatment rates to 9 percent. But if all patients with known onset times had called 9-1-1 immediately, they said the rate of intervention within three hours would have increased from 6 percent to 20 percent.
Also see Abstract #P345 (4 p.m. Friday) on the Ohio Prototype of the Paul Coverdell Acute Stroke Registry. This report found no racial differences in average times from stroke symptom onset to hospital arrival, but a need for better documentation of symptom onset times. EMS use was associated with faster arrivals for acute stroke patients.
4 p.m. Abstract P209 – Statins show promise for improving outcomes for acute ischemic stroke. Known for their ability to lower cholesterol and reduce heart attack risk, the drugs called statins in a small study appear to effectively improve neurological outcome after ischemic stroke. In the MISTICS trial, Spanish investigators conducted a pilot, double-blind, randomized trial on the safety and efficacy of the statin drug simvastatin in the acute phase of ischemic stroke. Of 56 patients (average age 73), 46.4 percent who got the statin drug showed significant neurological improvement by the third day, compared to 17.9 percent of those getting a placebo. Ten statin patients showed "great improvement" after 90 days in scores assessing their neurological function compared to three placebo patients. "Treatment with statins initiated in the acute phase of ischemic stroke may improve neurological outcome," the researchers reported. But they said an observed trend toward increased infections needs further study.
4 p.m. Abstract P210 – Oxygen therapy may be safe, boost neurological function after stroke. Pure oxygen administered within the first 12 hours after stroke symptom onset is safe and staves off brain tissue death, possibly allowing doctors more time to administer important clot-busting therapy, according to a small study of ischemic stroke patients. In a randomized trial, eight patients received 100 percent oxygen by facemask for eight hours, while four patients got only room air. The volume of brain tissue affected by the stroke decreased to 78 percent at three hours in the oxygen group; then increased to 114 percent at 24 hours and 194 percent at one week. In the control group, the volume of affected brain tissue increased to 145 percent at three hours, 229 percent at 24 hours and 253 percent at one week. There was no evidence of adverse effects from the 8-hour oxygen therapy. Early "hyperoxia" therapy appears safe and may improve clinical and MRI parameters after ischemic stroke, the scientists reported. They suggest oxygen treatment could become a widely used strategy to extend the "time window" available for effective therapy after iscemic stroke.
4 p.m. Abstract P232 – Clot-busting therapy plus angioplasty helps some stroke patients. Japanese doctors report promising results from experimentally combining clot-busting therapy with brain balloon angioplasty in patients with acute ischemic stroke leading to total blockage of the internal carotid artery. Sixteen patients received treatment with intra-arterial fibrinolysis plus balloon angioplasty. Reopening the blocked artery was achieved in six patients but not in the other 10. Another 38 patients received "conservative" treatment. Scores measuring neurological function were significantly improved in the six patients compared to the others. "Successful endovascular treatment for recanalization can probably improve clinical outcome even in patients showing serious symptoms due to acute embolic occlusion of the internal carotid artery," the researchers concluded.
4 p.m. Abstract P250 – All types of ischemic strokes occur most often in morning. From the Northern Manhattan Study comes new data showing that all types of ischemic strokes happen most often during morning hours. In a study of 735 patients, 44.8 percent of their strokes occurred between 6 a.m. and noon. And morning predominance persisted after researchers excluded patients with stroke upon awakening whose exact time of onset couldn't be established. Of 431 ischemic stroke patients with known onset times, 42.2 percent occurred between 6 a.m. and noon. Another 29.9 percent happened between noon and 6 p.m.; 22.5 percent, 6 p.m. and midnight, and 5.3 percent, midnight and 6 a.m. Morning onset was most common for all ischemic stroke subtypes: atherosclerotic, cardioembolic, lacunar and cryptogenic. By contrast, 54 bleeding strokes with known onset times occurred more uniformly during 24 hours. Patients over age 70 were more likely to have morning strokes than those age 70 and younger.
4 p.m. Abstract P271 – A pregnancy complication that increases the risk of mini-strokes. An inherited condition called cerebral autosomal dominant arteriopathy with sutbortical infarcts and leukoencephalopathy (CADASIL) can cause headaches, recurrent ischemic attacks, cognitive decline and dementia. Now Finnish researchers find that CADASIL, recognized as a cause of strokes in the young, poses a special risk during pregnancy. The team studied 19 pregnancies and post-birth periods (puerperium) of 12 women with the CADASIL gene mutation in which complications occurred. They found that transient neurological symptoms occurred in 17 (90 percent). In those 17 pregnancies, neurological deficits occurred during puerperium in 11 (65 percent) of these pregnancies. Symptoms included headache, vision problems, impaired speech and numbness. Pre-eclampsia-like symptoms occurred in six of the 19 problem pregnancies. "Pregnancy increases the risk of transient ischemic symptoms and pre-eclampsia in CADASIL in all age groups, but especially in older (over 30) females," the researchers reported.
Also see Abstract P259 (4 p.m. FRIDAY) for another CADASIL report finding an impaired peripheral "microcirculation" to the skin also occurs with this genetic defect.
4 p.m. Abstract P310 – High cholesterol doubles stroke risk in young women. A new study of young women suggests that high cholesterol levels may double their risk of stroke. In 59 Maryland and District of Columbia area hospitals, researchers identified 227 women ages 15-44 with strokes. A matched group of 392 healthy women served as controls. Pre-stroke medical histories including cholesterol data were obtained in interviews, and current total cholesterol (TC) and HDL-C levels were measured. Sixty-seven percent of the cases and 94 percent of the control group with high TC were not on cholesterol medication. In statistical modeling, researchers assessed relationships between stroke and self-reported high TC, measured TC and low HDL-C. They adjusted for age, race and education (Model 1), and further adjusted for smoking, alcohol, oral contraceptives, overweight, hypertension and heart disease (Model 2). In both models, stroke risk was twice as high in those with high TC (above 240 mg/dl). Low HDL-C (below 40 mg/dl) was also associated with 1.5 to 1.9 times the stroke risk. No association occurred with self-reported high TC. "High cholesterol may double stroke risk in the young," the researchers warned, adding: "Young adults lack awareness of cholesterol status and may receive inadequate treatment."
4 p.m. Abstract P337 – Depression raises risk of stroke and dementia in elderly women. While depression is common after stroke, little is known about the disorder as a risk factor for cerebrovascular disease. Scientists examined the prevalence of depression at age 85 and its relation to the incidence of stroke and dementia in 494 Swedish 85-year-olds. Depression data were obtained from psychiatric exams, and stroke occurrence monitored during a three-year follow-up. Information on dementia after three years also was gathered and diagnosis made according to standard methods. Depression prevalence at age 85 was 16 percent. The overall "hazard ratio" for stroke in those with depression was 2.2, compared to those not depressed. But when examined more closely, this risk held true only for women, whose hazard ratio was 2.7, compared to an HR of 0.7 in men. In depressed women at age 85, the hazard ratio for vascular dementia was 3.2, compared to those not depressed. Finding depression associated with such sharply higher risks of stroke and vascular dementia, the researchers called for studies to see if antidepressive treatment will reduce this later risk.
4 p.m. Abstract P347 – Many missed opportunities for secondary stroke prevention. In a statewide sample from 16 Michigan hospitals, researchers examined how well 14 "quality indicators" relevant to vital secondary prevention were used. Indicators included risk factor documentation, diagnostic testing and treatment interventions. Statistical methods evaluated application of each quality indicator in data collected on 2,342 stroke survivors. Except for smoking, risk factor documentation was poor, even in patients admitted to neurological services. Where protocols were followed and a neurologist was involved, there was more lipid testing and anti-clotting therapy. Men were more likely than women to have lipids measured and risk factors documented. Whites had better documentation of blood lipid disorders and heartbeat irregularities and were more likely to get treatment than nonwhites. More optimal secondary prevention occurs when protocols are used and neurologists are involved in care, the scientists reported. But, they said, "Some quality indicators were used less frequently in minority populations and women."
4 p.m. Abstract P282 – A gene variation that protects against stroke? A recently identified protein called growth arrest-specific 6 gene product (GAS6) has clot-producing effects. So a team of Spanish researchers looked at whether the prevalence of one variation of the GAS6 involving a single nucleotide polymorphism (SNP) differed among patients with ischemic or hemorrhagic stroke and healthy individuals. Genetic profiles were studied in 343 patients with ischemic strokes, 157 with hemorrhagic strokes, and 108 healthy controls. It turns out that one gene type with the SNP variant, the AA allele, was less prevalent than the GG allele among stroke patients than the healthy controls. Prevalence of ischemic stroke was 12.5 percent and hemorrhagic stroke 10.2 percent in the AA's, compared to 20.4 percent for controls. The GG allele was present in 40.2 percent of the ischemic stroke patients and 43.3 percent of the hemorrhagic stroke patients, compared to 43.5 percent for the controls. "This finding suggests that this genotype [GAS6-intron8 AA genotype] is associated to mechanisms protective against stroke that deserve further study."