EPIDEMIOLOGY OF SUBARACHNOID HEMORRHAGE IN FINLAND FROM 1983 TO 1985

The age-standardized incidence of subarachnoid hemorrhage was 33/100,000/yr among Finnish men and 25/100,000/yr among Finnish women. Subarachnoid hemorrhage represented 11% of all strokes detected during 1983-1985 in the community-based stroke register in three areas of Finland. Age-standardized mortality from subarachnoid hemorrhage was 18/100,000/yr among men and 12/100,000/yr among women aged 25-74 years, representing in men 22% and in women 23% of all deaths from stroke in the register. The case-fatality rate of subarachnoid hemorrhage was high: 35% among men and 33% among women within 2 days after the onset of the stroke attack and 48% in men and 46% in women at 1 month. Our findings suggest that the incidence and mortality of subarachnoid hemorrhage in Finland are among the highest worldwide, although differences in criteria, study methods, and classification procedures reduce the comparability of studies from different countries. The occurrence of subarachnoid hemorrhage in our present study is also higher than that previously reported in this country. We believe that this is more likely due to changes in diagnostic classification and improvements in detection of the disease than to a real increase in the morbidity and mortality of subarachnoid hemorrhage.