First-Ever Acute Stroke in the Very Elderly: A Retrospective Study in Akita Prefecture, Japan, 1996-1998

Abstract

Background: The highest life expectancy is registered in Japan for both women and men at the present. The stroke of the very elderly has different features than the younger’s’ one, but published data is still scarce on this topic. The very elderly seem to receive fewer vascular protection interventions that have been shown to be effective in younger individuals. Although there has been an underrepresentation of the very elderly in studies of stroke therapy, these treatments might be of benefit to this group of patients. Subjects and Methods: The subjects were selected from the Akita Stroke Registry with first-ever acute stroke from 1996 to 1998. Results: 8,046 cases were recorded, 7362 patients aged <85 years, and 684 patients aged ≥85 years. Sex ratio (w/m) was 0.84 and 1.89 in the two age groups. In the population of Akita the crude incidence of first-ever stroke was 222/100,000/year, and 1,085/100,000/year in the very elderly, who were characterized with significantly lower prevalence of stroke risk factors, except that of atrial fibrillation and cardiac diseases. The stroke subtype distribution in the two age groups (young/old) was significantly different (intracerebral haemorrhage 26.7% vs. 20.6%, infarction 60.0% vs. 73.2%, SAH 13.3% vs. 6.2%). Severity at onset was higher in the very elderly patients (consciousness disturbance 29.9% vs. 45.5% and severe motor deficit 75.6% vs. 86.4%). Both 28 day case fatality (10, 1% vs. 22.3%) and 1 year mortality rates (17.8% vs. 48.8%) were poorer in the very elderly. The most powerful prognostic factor of death was consciousness level at onset in both age groups. The following in order was the SAH stroke subtype. In the elder group the risk factors were not independent predictors of death, except diabetes for death within 28 days.