Time trends in incidence, mortality, and case-fatality after first episodeof status epilepticus

Purpose: Status epilepticus (SE) is a medical emergency associated with a h igh mortality. Clinical series have suggested that mortality after SE has d ecreased. No studies have systematically examined trends in incidence, mort ality, and case fatality after SE in a well-defined population. Methods: All First episodes of SE receiving medical attention between Janua ry 1, 1935, and December 31, 1984, were ascertained through the Rochester E pidemiology Project Records-Linkage System and followed up until death or s tudy termination (February 1, 1996). We calculated incidence rates in the 5 0-year period (1935-1984), while we considered mortality and case-fatality in the last 30-year period (1955-1984). Results: Incidence of SE increased over time to 18.1/100,000 (1975 through 1984). The increase was related to an increased incidence in the elderly an d to the advent of myoclonic SE after cardiac arrest, a condition not seen in the early decades. In the last decade, similar to 16% of the incidence w as due to myoclonic SE. The mortality rates increased from 3.6 per year in the decade 1955-1965 to 4.0/100,000 per year between 1975 and 1984. The 30- day case-fatality (CF) was unchanged, although a trend toward improvement w as shown after excluding myoclonic SE. Conclusions: Incidence and mortality rates of SE have increased in the last 30 years. Case fatality remained the same. The increased incidence and mor tality are due to the occurrence in the last decade of myoclonic SE after c ardiac arrest. The mortality in the elderly was twice that of the youngest age group, across all study periods. Changes in the age and cause distribut ion of SE over time are responsible for the stable survivorship. There is i mprovement in survivorship in the last decade when myoclonic SE is excluded .