Clinical scores and clusters for prediction of outcomes in status epilepticus

Periodic discharges and status epilepticus: A critical reappraisal

OBJECTIVE

Periodic Discharges (PDs) in Status Epilepticus (SE) are historically related to negative outcome, and the Epidemiology-based Mortality Score in SE (EMSE) identifies PDs as an EEG feature associated with unfavorable prognosis. However, supportive evidence is conflicting. This study aims to evaluate the prognostic significance of interictal PDs during and following SE.

METHODS

All 2020-2023 non-hypoxic-ischemic SE patients with available EEG during SE were retrospectively assessed. Interictal PDs during SE (SE-PDs) and PDs occurring 24-72 h after SE resolution (post-SE-PDs) were examined. In-hospital death was defined as the primary outcome.

RESULTS

189 SE patients were finally included. SE-PDs were not related to outcome, while post-SE-PDs were related to poor prognosis confirmed after multiple regression analysis. EMSE global AUC was 0.751 (95%CI:0.680-0.823) and for EMSE-64 cutoff sensitivity was 0.85, specificity 0.52, accuracy 63%. We recalculated EMSE score including only post-SE-PDs. Modified EMSE (mEMSE) global AUC was 0.803 (95%CI:0.734-0.872) and for mEMSE-64 cutoff sensitivity was 0.84, specificity 0.68, accuracy 73%.

CONCLUSION

Interictal PDs during SE were not related to outcome whereas PDs persisting or appearing > 24 h after SE resolution were strongly associated to unfavorable prognosis. EMSE performed well in our cohort but considering only post-SE-PDs raised specificity and accuracy for mEMSE64 cutoff.

SIGNIFICANCE

This study supports the utility of differentiating between interictal PDs during and after SE for prognostic assessment.

The risk of unprovoked seizure occurrence after status epilepticus in adults

OBJECTIVE

Status epilepticus (SE) may lead to long-term consequences. This study evaluated the risk and predictors of seizure occurrence after SE, with a focus on SE due to acute symptomatic etiologies.

METHODS

Prospectively collected data about adults surviving a first non-hypoxic SE were reviewed. The outcome was the occurrence of unprovoked seizures during the follow-up. Kaplan-Meier survival curve analysis and log-rank test were used to analyze the time to seizure occurrence and determine the statistical significance between etiological groups. Three subcategories within acute etiology were considered according to the presence of the following: (1) structural lesion (acute-primary); (2) brain involvement during systemic disorders (acute-secondary); and (3) drug or alcohol intoxication/withdrawal (acute-toxic). Cox proportional hazards model was adopted to estimate hazard ratios (HRs) with the 95% confidence intervals (CIs).

RESULTS

Two hundreds fifty-seven individuals were included. Fifty-four subjects (21.0%) developed seizures after a median of 9.9 (interquartile range 4.3-21.7) months after SE. The estimated 1-, 2-, and 5-year rates of seizure occurrence according to acute SE etiologies were 19.4%, 23.4%, and 30.1%, respectively, for acute-primary central nervous system (CNS) pathology; 2.2%, 2.2%, and 8.7%, respectively, for acute-secondary CNS pathology; and 0%, 9.1%, and 9.1%, respectively, for acute-toxic causes. Five-year rates of seizure occurrence for non-acute SE causes were 33.9% for remote, 65.7% for progressive, and 25.9% for unknown etiologies. In multivariate Cox regression model, progressive etiology (adjusted HR [adjHR] 2.27, 95% CI 1.12-4.58), SE with prominent motor phenomena evolving in non-convulsive SE (adjHR 3.17, 95% CI 1.38-7.25), and non-convulsive SE (adjHR 2.38, 95% CI 1.16-4.90) were independently associated with higher hazards of unprovoked seizures. Older people (adjHR .98, 95% CI .96-.99) and people with SE due to acute-secondary CNS pathology (adjHR .18, 95% CI .04-.82) were at decreased risk of seizure occurrence.

SIGNIFICANCE

SE carries a risk of subsequent seizures. Both the underlying cause and epileptogenic effects of SE are likely to contribute.

How much refractory is 'refractory status epilepticus'? A retrospective study of treatment strategies and clinical outcomes

BACKGROUND AND PURPOSE

This study aimed to evaluate whether differences in clinical outcomes exist according to treatments received and seizure activity resolution in patients with refractory status epilepticus (RSE).

METHODS

Consecutive episodes of non-hypoxic status epilepticus (SE) in patients ≥ 14 years old were included. Episodes of RSE were stratified in: (i) SE persistent despite treatment with first-line therapy with benzodiazepines and one second-line treatment with antiseizure medications (ASMs), but responsive to successive treatments with ASMs (RSE-rASMs); (ii) SE persistent despite treatment with first-line therapy with benzodiazepines and successive treatment with one or more second-line ASMs, but responsive to anesthetic drugs [RSE-rGA (general anesthesia)]. Study endpoints were mortality during hospitalization and worsening of modified Rankin Scale (mRS) at discharge.

RESULTS

Status epilepticus was responsive in 298 (54.1%), RSE-rASMs in 152 (27.6%), RSE-rGA in 46 (8.3%), and super-refractory (SRSE) in 55 (10.0%) out of 551 included cases. Death during hospitalization occurred in 98 (17.8%) and worsening of mRS at discharge in 287 (52.1%) cases. Multivariable analyses revealed increased odds of in-hospital mortality with RSE-rGA (odds ratio [OR] 3.05, 95% confidence interval [CI] 1.27-7.35) and SRSE (OR 3.83, 95%. CI 1.73-8.47), and increased odds of worsening of mRS with RSE-rASMs (OR 2.06, 95% CI 1.28-3.31), RSE-rGA (OR 4.44, 95% CI 1.97-10.00), and SRSE (OR 13.81, 95% CI 5.34-35.67).

CONCLUSIONS

In RSE, varying degrees of refractoriness may be defined and suit better the continuum spectrum of disease severity and the heterogeneity of SE burden and prognosis.

Acute symptomatic status epilepticus: Splitting or lumping? A proposal of classification based on real-world data

This study aimed to group acute symptomatic etiologies of consecutive episodes of status epilepticus (SE) into different subcategories and explore their associations with clinical outcome. Etiologies were first categorized as "acute," "remote," "progressive," "SE in defined electroclinical syndromes," and "unknown." Four subcategories of acute etiologies were then defined: (1) withdrawal, low levels, or inappropriate prescription of antiseizure medications, or sleep deprivation in patients with pre-existing epilepsy; (2) acute insults to central nervous system (CNS; "acute-primary CNS"); (3) CNS pathology secondary to metabolic disturbances, systemic infection, or fever ("acute-secondary CNS"); and (4) drug/alcohol intoxication or withdrawal. Poor outcome at discharge, defined as worsening of clinical conditions (modified Rankin Scale [mRS] at discharge higher than mRS at baseline), was reported in 55.6% of cases. The etiological categories of acute-primary CNS (odds ratio [OR] = 3.61, 95% confidence interval [CI] = 2.11-6.18), acute-secondary CNS (OR = 1.80, 95% CI = 1.11-2.91), and progressive SE (OR = 2.65, 95% CI = 1.57-4.47), age (OR = 1.05, 95% CI = 1.04-1.06), nonconvulsive semiology with coma (OR = 3.06, 95% CI = 1.52-6.17), and refractoriness (OR = 4.31, 95% CI = 2.39-7.77) and superrefractoriness to treatment (OR = 8.24, 95% CI = 3.51-19.36) increased the odds of poor outcome. Heterogeneity exists within the spectrum of acute symptomatic causes of SE, and distinct etiological subcategories may inform about the clinical outcome.