Status epilepticus in older adults: A critical review

Older adults (≥60 years of age) have the highest incidence of status epilepticus (SE) among adults and experience the highest morbidity and mortality. SE incidence increases with age in adulthood. A recent study from Austria estimated an incidence of 89.6/100 000 and 67.6/100 000 person-years adjusted for age and sex in women and men aged >60 years, respectively, compared to 18.1/100 000 in adults aged <60 years. In-hospital mortality associated with SE increases fourfold from the 3rd to 9th decade of life. There are multiple important considerations unique to older adults. Etiologies, including ischemia, hemorrhage, and neoplasm, are more common in older adults and are independently associated with poorer outcomes. Important physiological changes of aging affect both the pharmacokinetics and pharmacodynamics of established treatments for SE. Pharmacology studies have shown differences in sensitivity to benzodiazepines and benzodiazepine elimination, as well as greater unpredictability of antiseizure medications such as phenytoin. Older adults have been largely underrepresented in high-quality randomized clinical trials of SE treatment relative to the incidence of SE in this population. The Established Status Epilepticus Treatment Trial published a post hoc analysis of older adults that showed similar efficacy of treatments, although many older trials did not stratify by age, limiting the opportunity to recognize age-related differences in efficacy and safety. Future research should be aimed at investigating treatment selection and dosing in older adults with SE.