Hospital-based prospective registration of acute ischemic stroke and transient ischemic attack in Japan

The purpose of this study was to determine the incidence, recurrence, and long-term survival rates of ischemic stroke subtypes by a mechanism-based classification scheme (Trial of ORG 10172 in Acute Stroke Treatment, or TOAST). We identified all 583 residents of the city of Erlangen, Bavaria, Germany, with a first ischemic stroke between 1994 and 1998. Multiple overlapping sources of information were used to ensure completeness of case ascertainment. The cause of ischemic stroke was classified according to the TOAST criteria. Patients were followed up at 3 months and 1 and 2 years after stroke onset. The age-standardized incidence rates for the European population (per 100 000) regarding ischemic stroke subtypes were as follows: cardioembolism, 30.2 (95% CI 25.6 to 35.7); small-artery occlusion, 25.8 (95% CI 21.5 to 30.9); and large-artery atherosclerosis, 15.3 (95% CI 12 to 19.3). When age-adjusted to the European population, the incidence rate for large-artery atherosclerosis was more than twice as high for men than for women (23.6/100 000 versus 9.2/100 000). Two years after onset, patients in the small-artery occlusion subgroup were 3 times more likely to be alive than those with cardioembolism. Ischemic stroke subtype according to the TOAST criteria was a significant predictor for long-term survival, whereas subtype was not a significant predictor of long-term recurrence up to 2 years, both before and after adjustment for age and sex. Epidemiological observational studies that possess wide access to appropriate diagnostic technologies and apply standardized etiologic classifications provide a much better understanding of underlying risk factors for initial stroke, recurrence, and mortality.

Thrombolytic therapy for acute stroke (<3 hours) will not have a major impact on death and dependency unless it is accessible to more patients. To determine why patients with ischemic stroke did not receive IV TPA and assess the availability of this therapy to patients with ischemic stroke. Consecutive patients with acute ischemic stroke were prospectively identified at a university teaching hospital between October 1996 and December 1999. Additional patients with ischemic stroke were identified that were admitted to one of three other hospitals in the Calgary region during the study period. The Oxford Community Stroke Programme Classification was used to record type and side of stroke. Of 2165 stroke patients presenting to the university hospital, 1168 (53.9%) were diagnosed with ischemic stroke, 31.8% with intracranial hemorrhage (intracerebral, subarachnoid, or subdural), and 13.9% with TIA. Delay in presentation to emergency department beyond 3 hours excluded 73.1% (854/1168). Major reasons for delay included uncertain time of onset (24.2%), patients waited to see if symptoms would improve (29%), delay caused by transfer from an outlying hospital (8.9%), and inaccessibility of treating hospital (5.7%). Twenty-seven percent of patients with ischemic stroke (314/1168) were admitted within 3 hours of sympton onset and of these 84 (26.7%) patients received IV TPA. The major reasons for exclusion in this group of patients (<3 hours) were mild stroke (13.1%), clinical improvement (18.2%), perceived protocol exclusions (13.6%), emergency department referral delay (8.9%), and significant comorbidity (8.3%). Of those patients who were considered too mild or were documented to have had significant improvement, 32% either remained dependent at hospital discharge or died during hospital admission. Throughout the region there was a total of 1806 ischemic stroke patients (admitted to all four Calgary hospitals). During this study period, 4.7% received IV TPA. The majority of patients are unable to receive TPA for acute ischemic stroke because they do no not reach the hospital soon enough. Of those patients presenting within 3 hours, 27% received the therapy but a further 31% were excluded because their symptoms were either considered too mild or were rapidly improving. Subsequently, a third of these patients were left either dependent or dead, bringing into question the initial decision not to treat.