Stroke subtypes and lesion sites in Akita, Japan

Stroke patients who underwent computed tomography (CT) were enrolled in a stroke registry in Akita, Japan, which comprised 7288 first-ever stroke cases during 1999 to 2001. Differences in age and sex were evaluated with respect to type-specific incidences and lesion sites. The incidence increased with age, except for subarachnoid hemorrhage (SAH) in men after age 40. The incidence of intracerebral hemorrhage (IH) and cerebral infarction (CI) was higher in men than in women, whereas that for SAH was lower. The mean age of putaminal hemorrhage was lower than that of thalamic hemorrhage, and the mean age of cortical infarction was higher than that of CI in perforator regions, the cerebellum, and the pons. In subjects age 70 years and older, the proportion of thalamic hemorrhage in IH was larger in women than in men; for those age 50 years and older, the proportion of cortical infarction in CI was larger in men than in women. The proportions of anterior communicating artery aneurysms in men and internal carotid artery aneurysms in women were largest in SAH for all age groups. In conclusion, thalamic hemorrhage was most common in elderly women and cortical infarction was most common in middle-aged and elderly men. The feature of SAH occurring at a higher incidence in women than in men, with a sexual difference in aneurysmal distribution, was also observed.