Mortality Risk in an Adult Cohort with a Newly Diagnosed Unprovoked Epileptic Seizure: A Population-Based Study

Authors


Address correspondence and reprint requests to Dr. Hans Lindsten at Department of Neurology, Umeå University Hospital, S-901 85 Umeå, Sweden. E-mail: Hans.Lindsten.us@vll.se

Abstract

Summary: Purpose: We sought to investigate mortality risk in an adult cohort with newly diagnosed unprovoked epileptic seizures.

Methods: One hundred seven patients who were at least 17 years old and had newly diagnosed unprovoked epileptic seizures were prospectively identified during a period of 20 months between 1985 and 1987. Patients were followed until the date of death or the end of 1996. The standard mortality ratio (SMR) was analyzed in the whole cohort and in the portion of the cohort with recurrent seizures at inclusion. The influences on the SMR of time since diagnosis, sex, age at diagnosis, seizure cause, seizure type, and cause of death were also investigated.

Results: The SMR was significantly increased (SMR, 2.5; 95% confidence interval [CI], 1.2–3.2). This significantly increased risk was found during the first 2 years after diagnosis (year 1: SMR, 7.3; 95% CI, 4.4–12.1; year 2: SMR, 3.6; 95% CI, 1.6–8.1) and at years 9–11 (SMR, 5.4; 95% CI, 2.7–11.2). The increased mortality risk was most pronounced when the seizures occurred before the age of 60 years. Mortality risk was elevated among patients with remote symptomatic epilepsy (SMR, 3.3; 95% CI, 2.4–4.5) but not idiopathic epilepsy.

Conclusions: There is increased mortality risk in an adult cohort with newly diagnosed unprovoked epileptic seizures. This increase is found in symptomatic patients, young patients, and during the first 2 years after the diagnosis.

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