Abstract
The Northern Hokkaido Stroke Study (NOHSS) is a population-based study. We started the stroke registration system in this area, and evaluated the type of stroke, risk factors, outcome, and recurrence rate for 9 years. Between July 1, 2002 and June 30, 2011, 2345 patients (56.6% male and 43.4% female) with acute stroke were registered. The mean age (±SD) of patients were 72.2±12.1. The type of stroke distribution was cerebral infarction in 66.1%, intracerebral hemorrhage in 23.5%, subarachnoid hemorrhage in 9.9%. The clinical category of cerebral infarction was lacunar in 38.1%, atherothrombosis in 31.2%, cardioembolism in 26.6%. In total 2345 cases, 197 cases were recurrent strokes. The annual recurrence rate was 3.8%. We divide the patients into 3 groups every 3 years of the registered period and analyzed clinical data among the groups. We found that intracerebral hemorrhage decreases and cerebral infarction increases for the 9 years. In ischemic stroke subtypes, cardioembolism increases statistically. We also found that anticoagulation therapy, as prevention to cardioembolism, is popularized gradually.
