Clinico-epidemiologic study of stroke in Akita, Japan.

An analysis was performed of 2,168 consecutive stroke patients who were examined by computed tomography and entered into a hospital-based stroke registry in Akita Prefecture, Japan. The occurrence of cerebral hemorrhage, cerebral infarction, and subarachnoid hemorrhage was 30, 55, and 14%, respectively. Age-specific rates of subarachnoid hemorrhage were higher in women than men; other types of stroke showed a preponderance in men. Total strokes increased in the winter; this seasonal difference was confined to cerebral hemorrhage. Putaminal hemorrhages predominated in the younger age groups; thalamic hemorrhage and cerebellar hemorrhage were predominant in the older age groups. The increased accuracy of the diagnosis of stroke subtypes by the use of computed tomography in this study is in contrast to other community-based epidemiologic studies that have relied solely on clinical diagnosis. This increased accuracy is seen to be the reason that new ratios of stroke subtype incidence have been identified.