Trends in hospitalization rate, hospital case fatality, and mortality rate of stroke by subtype in Minneapolis-St. Paul, 1980-2002

Background: The stroke mortality rates have been declining in the USA for decades. Less is known about trends in stroke incidence rates, but some studies indicate they have declined. The stroke case fatality has also been declining. Little information exists on trends in stroke subtypes. We examined trends in mortality, hospitalization rate, and hospital case fatality of stroke by subtype in the Minneapolis-St. Paul area from 1980 to 2002. Methods: We estimated hospitalization rates and case fatality for ≥30-year-olds with data from the Minnesota Hospital Association. We estimated mortality rates with counts from the Minnesota Department of Health. Rates were age adjusted to the US 2000 standard by the direct method using census estimates. We tested for significant trends using linear regression. Results: Total stroke mortality and hospital case fatality both declined by almost 50% over the study period, while the rate of stroke hospitalization was relatively stable. Ischemic stroke hospitalization rates increased, while hospital case fatality and mortality rates decreased. Subarachnoid hemorrhage in-hospital case fatality and mortality rates declined, while the hospitalization rate was stable. Intracerebral hemorrhage hospitalization rates increased minimally, hospital case fatality declined, and the mortality rate was stable. Conclusion: These data suggest that declines in total stroke case fatality are contributing most to declining mortality rates in the presence of stable total stroke attack rates.