Predictors of mortality at one year after generalized convulsive status epilepticus

Mortality and morbidity of status epilepticus over the long term

Status epilepticus is associated with high mortality and morbidity, both in the acute phase and over the long term. However, the long-term outcome of SE is not well studied, and there is no consensus on how to measure and predict it. Moreover, the factors that influence the long-term outcome of SE are complex and multifactorial, and may vary depending on the patient's characteristics, the SE etiology and type, and the treatment and complications. The aim of this article is to review the current literature on the mortality and morbidity of SE over the long term and to discuss the challenges and perspectives for future research. Proceedings of the 9th London-Innsbruck Colloquium on Status Epilepticus and acute seizures.

Clinical Outcomes and Systemic Complications Related to the Severity and Etiology of Status Epilepticus Using a Common Data Model

BACKGROUND

Status epilepticus (SE) is a critical neurological emergency in patients with neurological and nonneurological diseases. Mortality rises with SE severity. However, whether brain injury or systemic organ dysfunction causes death after SE remains unclear. We studied clinical outcomes and systemic dysfunctions associated with SE using standardized data from the common data model. This model includes clinical evaluations and treatments that provide real-world evidence for standard practice.

METHODS

This retrospective cohort study used the common data model database of a single tertiary academic medical center. Patients diagnosed with SE (corresponding to G41 of the International Classification of Diseases 10 and administration of antiseizure medication) between January 1, 2001, and January 1, 2018, were enrolled. Demographics, classifications of SE severity, and outcomes were collected as operational definitions by using a common data model format. Systemic complications were defined based on the Sequential Organ Failure Assessment criteria.

RESULTS

The electronic medical records of 1,825,196 patients were transformed into a common data model, and 410 patients were enrolled. The proportion of patients classified as having nonrefractory SE was 65.4% (268/410), followed by refractory (28.5%, 117/410) and super-refractory SE (6.1%, 25/410). Patients with more severe SE had longer intensive care unit and hospital stays. Renal dysfunction and thrombocytopenia were higher in the in-hospital death group (P = 0.002 and 0.003, respectively). In multivariable analysis, the Acute Physiology and Chronic Health Evaluation II score and platelet count were significantly different in the in-hospital death group (odds ratio, 1.169, P = 0.004; and 0.989, P = 0.043).

CONCLUSIONS

Systemic complications after SE, especially low platelet counts, were linked to worse outcomes and increased mortality in a common data model. The common data model offers expandability and comprehensive analysis, making it a potentially valuable tool for SE research.

Mortality, Disability and Prognostic Factors of Status Epilepticus: A Nationwide Population-Based Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

The outcome of status epilepticus (SE) largely varies depending on clinical characteristics. Risk stratification is necessary for tailoring the aggressiveness of treatment and predicting outcomes of individual patients with SE. In this study, we assessed differences in mortality, neurologic disability, and prognostic factors associated with SE across sociodemographic and clinical characteristics.

METHODS

We conducted a nationwide population-based retrospective cohort study using the National Health Insurance Service (NHIS) database linked with the national death and disability registries. SE was identified from admission or emergency room visits using a diagnostic code of G41 from the International Classification of Disease, 10^th Revision. Individuals with new-onset SE that occurred from January 1, 2010, to December 31, 2018, were included. Active epilepsy, refractoriness of SE, potential etiology, and comorbidities were ascertained by diagnostic codes and/or prescription records from the NHIS database as potential prognostic factors. Outcomes included 30-day and 1-year mortality and neurologic disabilities following SE. Prognostic factors for mortality were assessed by the Cox regression hazard model. We performed a subgroup analysis according to age: pediatric SE (age < 20 years old) and adult SE (age ≥ 20 years old).

RESULTS

A total of 33,814 new-onset SE patients were included (6,818 children/adolescents and 26,996 adults). The 30-day mortality was 8.5% (1.8% in pediatric SE and 10.2% in adult SE), and the 1-year mortality was 25.1% (4.6% in pediatric SE and 30.3% in adult SE). Overall, 10.7% of patients newly acquired neurologic disabilities following SE, with the highest incidence in children aged 5 to 9 years (21.3%). Intractable epilepsy developed in 0.8% of entire SE. Old age, presence of acute etiology, and refractoriness were poor prognostic factors for mortality in both pediatric and adult SE. Male sex, low economic status, no active epilepsy, and comorbidities were additional factors for a poor prognosis in adults.

CONCLUSIONS

New-onset SE was associated with substantial mortality and disability. While SE-related mortality was higher in adults, disabilities developed more commonly in children and adolescents. The major determinants of mortality differed between pediatric and adult SE.

Status epilepticus after intracranial neurosurgery: incidence and risk stratification by perioperative clinical features

OBJECTIVE

Status epilepticus (SE) is associated with significant mortality, cost, and risk of future seizures. In one of the first studies of SE after neurosurgery, the authors assess the incidence, risk factors, and outcome of postneurosurgical SE (PNSE).

METHODS

Neurosurgical admissions from the MarketScan Claims and Encounters database (2007 through 2015) were assessed in a longitudinal cross-sectional sample of privately insured patients who underwent qualifying cranial procedures in the US and were older than 18 years of age. The incidence of early (in-hospital) and late (postdischarge readmission) SE and associated mortality was assessed. Procedural, pathological, demographic, and anatomical covariates parameterized multivariable logistic regression and Cox models. Multivariable logistic regression and Cox proportional hazards models were used to study the incidence of early and late PNSE. A risk-stratification simulation was performed, combining individual predictors into singular risk estimates.

RESULTS

A total of 197,218 admissions (218,217 procedures) were identified. Early PNSE occurred during 637 (0.32%) of 197,218 admissions for cranial neurosurgical procedures. A total of 1045 (0.56%) cases of late PNSE were identified after 187,771 procedure admissions with nonhospice postdischarge follow-up. After correction for comorbidities, craniotomy for trauma, hematoma, or elevated intracranial pressure was associated with increased risk of early PNSE (adjusted OR [aOR] 1.538, 95% CI 1.183-1.999). Craniotomy for meningioma resection was associated with an increased risk of early PNSE compared with resection of metastases and parenchymal primary brain tumors (aOR 2.701, 95% CI 1.388-5.255). Craniotomies for infection or abscess (aHR 1.447, 95% CI 1.016-2.061) and CSF diversion (aHR 1.307, 95% CI 1.076-1.587) were associated with highest risk of late PNSE. Use of continuous electroencephalography in patients with early (p < 0.005) and late (p < 0.001) PNSE rose significantly over the study time period. The simulation regression model predicted that patients at high risk for early PNSE experienced a 1.10% event rate compared with those at low risk (0.07%). Similarly, patients predicted to be at highest risk for late PNSE were significantly more likely to eventually develop late PNSE than those at lowest risk (HR 54.16, 95% CI 24.99-104.80).

CONCLUSIONS

Occurrence of early and late PNSE was associated with discrete neurosurgical pathologies and increased mortality. These data provide a framework for prospective validation of clinical and perioperative risk factors and indicate patients for heightened diagnostic suspicion of PNSE.