Managing Status Epilepticus in the Older Adult

Comparative analysis of patients with new onset refractory status epilepticus preceded by fever (febrile infection-related epilepsy syndrome) versus without prior fever: An interim analysis

Febrile infection-related epilepsy syndrome (FIRES) is a subset of new onset refractory status epilepticus (NORSE) that involves a febrile infection prior to the onset of the refractory status epilepticus. It is unclear whether FIRES and non-FIRES NORSE are distinct conditions. Here, we compare 34 patients with FIRES to 30 patients with non-FIRES NORSE for demographics, clinical features, neuroimaging, and outcomes. Because patients with FIRES were younger than patients with non-FIRES NORSE (median = 28 vs. 48 years old, p = .048) and more likely cryptogenic (odds ratio = 6.89), we next ran a regression analysis using age or etiology as a covariate. Respiratory and gastrointestinal prodromes occurred more frequently in FIRES patients, but no difference was found for non-infection-related prodromes. Status epilepticus subtype, cerebrospinal fluid (CSF) and magnetic resonance imaging findings, and outcomes were similar. However, FIRES cases were more frequently cryptogenic; had higher CSF interleukin 6, CSF macrophage inflammatory protein-1 alpha (MIP-1a), and serum chemokine ligand 2 (CCL2) levels; and received more antiseizure medications and immunotherapy. After controlling for age or etiology, no differences were observed in presenting symptoms and signs or inflammatory biomarkers, suggesting that FIRES and non-FIRES NORSE are very similar conditions.

Incidence of First-Episode Status Epilepticus and Risk Factors in Ontario, Canada

BACKGROUND

Status epilepticus (SE) is a neurological emergency characterized by prolonged seizures. However, the incidence of first-episode SE is unclear, as estimates vary greatly among studies. Additionally, SE risk factors have been insufficiently explored. Therefore, the objectives of this study were to estimate the incidence of first-episode SE in Ontario, Canada, and estimate the associations between potential sociodemographic and health-related risk factors and first-episode SE.

METHODS

We conducted a population-based retrospective cohort study using linked health administrative datasets. We included individuals who completed Canada's 2006 Census long-form questionnaire, lived in Ontario, were between 18 and 105, and had no history of SE. A Cox proportional hazards regression model was used to estimate the hazard ratios for SE within three years associated with each potential risk factor.

RESULTS

The final sample included 1,301,700 participants, 140 of whom were hospitalized or had an emergency department visit for first-episode SE during follow-up (3.5 per 100,000 person-years). Older age was the only significant sociodemographic SE risk factor (HR = 1.35, 95% CI = 1.33, 1.37), while health-related risk factors included alcohol or drug abuse (HR = 1.05, 95% CI = 1.02, 1.08), brain tumour or cancer (HR = 1.14, 95% CI = 1.12, 1.15), chronic kidney disease (HR = 1.32, 95% CI = 1.29, 1.36), dementia (HR = 1.42, 95% CI = 1.36, 1.48), diabetes (HR = 1.11, 95% CI = 1.09, 1.12), epilepsy or seizures (HR = 1.05, 95% CI = 1.01, 1.09) and stroke (HR = 1.08, 95% CI = 1.05, 1.11).

CONCLUSION

The estimated incidence of SE in a sample of Ontario residents was 3.5 per 100,000 person-years. Older age and several comorbid conditions were associated with higher first-episode SE risk.

Management of Status Epilepticus, Refractory Status Epilepticus, and Super-refractory Status Epilepticus

PURPOSE OF REVIEW

Status epilepticus is a serious condition caused by disorders and diseases that affect the central nervous system. In status epilepticus, hypersynchronous epileptic activity lasts longer than the usual duration of isolated self-limited seizures (time t1), which causes neuronal damage or alteration of neuronal networks at a certain time point (time t2), depending on the type of and duration of status epilepticus. The successful management of status epilepticus includes both the early termination of seizure activity and the earliest possible identification of a causative etiology, which may require independent acute treatment. In nonconvulsive status epilepticus, patients present only with subtle clinical signs or even without any visible clinical manifestations. In these cases, EEG allows for the assessment of cerebral function and identification of patterns in need of urgent treatment.

RECENT FINDINGS

In 2015, the International League Against Epilepsy proposed a new definition and classification of status epilepticus, encompassing four axes: symptomatology, etiology, EEG, and age. Various validation studies determined the practical usefulness of EEG criteria to identify nonconvulsive status epilepticus. The American Clinical Neurophysiology Society has incorporated these criteria into their most recent critical care EEG terminology in 2021. Etiology, age, symptomatology, and the metabolic demand associated with an increasing duration of status epilepticus are the most important determinants of prognosis. The consequences of status epilepticus can be visualized in vivo by MRI studies.

SUMMARY

The current knowledge about status epilepticus allows for a more reliable diagnosis, earlier treatment, and improved cerebral imaging of its consequences. Outcome prediction is a soft tool for estimating the need for intensive care resources.

Treatment of established status epilepticus in the elderly - a study protocol for a prospective multicenter double-blind comparative effectiveness trial (ToSEE)

BACKGROUND

Status epilepticus (SE) is a common neurological emergency condition that especially affects the elderly and old population. Older people with SE frequently have non-convulsive SE (NCSE) and are also at special risk of suffering a poor outcome. The application of benzodiazepines fails to control SE in about one third of the cases. For benzodiazepine refractory SE (BRSE) in elderly, there is little evidence that would justify the choice of one of the commonly used antiepileptic drugs. The present study aims to generate evidence for the treatment of BRSE in this age group.

METHODS

We will conduct a prospective, randomized, double-blind comparative effectiveness study in more than twenty hospitals in Germany over a four-year period. Four hundred and seventy-seven elderly patients (≥ 65 years old) diagnosed with BRSE will be allocated by 1:1 randomization to receive either levetiracetam or valproate. All types of SE will be considered. For the diagnosis NCSE a verification by EEG is required. Levetiracetam or valproate will be administered in one single infusion. The primary endpoint is the stable cessation of ictal activity 15 min after the start of infusion persisting for the following 45 min of observation. EEG recording is maintained over the whole observation period, clinical examinations are conducted in predefined intervals. In case of treatment success patients and study staff remain blinded until 60 min after the start of the infusion. Adverse events will be recorded until the end of the study. EEG data will be reviewed by two external independent experts. To obtain data about the further treatment of SE, intrahospital complications and the functional outcome in the short term the study participants will be observed until the day of discharge or day 30 whichever is earliest.

DISCUSSION

ToSEE is the first study which shall deliver evidence for the SE-therapy in the elderly and old population in a controlled prospective comparator study. By design it also shall collect information about therapy regimes and outcome aspects of this disease.

TRIAL REGISTRATION

The trial has been registered at the German Clinical Trials Register on 3 July, 2020 ( DRKS00022308 ,  https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022308 ).

[Epilepsy in old age]

In an aging society, epilepsy in old age will become a more and more relevant disease. The diagnosis is often difficult because of the frequent occurrence of focal seizures in old age, which are easily overlooked. The diagnosis is often delayed, particularly in older patients who, for example also suffer from dementia. The causes of the epilepsy can be manifold in the aging brain. Another challenge for neurologists is the medicinal treatment of geriatric epilepsy, as many anticonvulsive drugs can be associated with serious side effects and interactions. The evidence for the effectiveness and tolerability of anticonvulsive drugs in old age is insufficient, so that the choice of drugs must be made on an individual basis. Status epilepticus is a neurological emergency, which occurs not only more frequently in older than in younger persons but is also associated with a higher mortality, so that immediate diagnosis and adequate treatment is necessary.

Etiological assessment of status epilepticus

Status epilepticus (SE) is a potentially serious condition that can affect vital and functional prognosis and requires urgent treatment. Etiology is a determining factor in the patient's functional outcome and in almost half of all cases justifies specific treatment to stop progression. Therefore, identifying and addressing the cause of SE is a key priority in SE management. However, the etiology can be difficult to identify among acute and remote causes, which can also be multiple and interrelated. The most common etiologies are the discontinuation of antiepileptic medication in patients with a prior history of epilepsy, and acute brain aggression in cases of new onset SE (cerebrovascular pathologies are the most common). The list of remaining possible etiologies includes heterogeneous pathological contexts. Refractory SE and especially New-Onset Refractory Status Epilepticus (NORSE) lead to an extension of the etiological assessment in the search for encephalitis of autoimmune or infectious origin in adults and in children, as well as a genetic pathology in children in particular. This is an overview of current knowledge of SE etiologies and a pragmatic approach for carrying out an etiological assessment based on the following steps: - Which etiological orientation is identified according to the field and clinical presentation?; - Which etiologies to look for in an inaugural SE?; - Which first-line assessment should be carried out? The place of the biological, EEG and imaging assessment is discussed; - Which etiologies to look for in case of refractory SE?

Epilepsy in the elderly: Unique challenges in an increasingly prevalent population

Elderly individuals (aged at least 60 or 65 years) represent a rapidly growing segment of the population. The incidence and prevalence of epilepsy is higher in this age group than in any other. Diagnosing epilepsy in the elderly can be challenging because the causes and clinical manifestations of seizures often differ as compared with younger individuals. Particular differential diagnoses, such as syncope and amyloid spells, are commonly encountered in the elderly population. A diagnosis of epilepsy has important implications in the older adult, many of which already present a variety of concomitant complex medical problems, such as cognitive impairment, comorbid cerebrovascular disease, and frailty. The treatment of epilepsy in the elderly is complicated by a variety of factors related to aging, including physiological changes, medical comorbidities, and polypharmacy. In this narrative review, we will address the descriptive epidemiology, clinical presentation, differential diagnosis, diagnostic evaluation, treatment, and prognosis of epilepsy in the elderly individual.

The medical treatment of epilepsy in the elderly: A systematic review and meta-analysis

OBJECTIVE

To evaluate the efficacy and tolerability of antiepileptic drugs (AEDs) in elderly individuals with epilepsy.

METHODS

We searched four electronic databases as well as bibliographies and conference abstracts. Published and unpublished, randomized, or quasirandomized trials reporting the use of AEDs in people aged at least 60 years with epilepsy were eligible for inclusion. Two authors independently carried out each stage of the review. Meta-analyses were performed using random-effects models.

RESULTS

Three thousand four hundred seventeen titles and abstracts were reviewed. Eighteen studies evaluating 12 AEDs met all eligibility criteria. Ten studies, comprising 1999 subjects, were suitable for meta-analysis. Among the elderly with epilepsy, lamotrigine (LTG) is better tolerated relative to carbamazepine (pooled weighted risk ratio [RR] of experiencing withdrawal due to adverse events = 1.83, 95% confidence interval [CI] = 1.23-2.43). There is a higher probability, although with a 95% CI of borderline importance, of seizure freedom when comparing levetiracetam to LTG (RR = 0.83, 95% CI = 0.68-0.97). Single studies provide evidence for the efficacy and/or tolerability of other AEDs in the elderly, including brivaracetam, gabapentin, lacosamide, perampanel, and topiramate. The risk of bias of the included studies was frequently low or unclear, although there was on occasion a high risk of bias (especially with regard to selective reporting).

SIGNIFICANCE

There is some evidence for AED use in the elderly with epilepsy. More evidence is required, comparing newer AEDs to prior generations as well as examining the effects of determinants such as frailty, to guide clinicians when treating this rapidly growing patient population.

Status epilepticus in the elderly

Children and the elderly (≥60 years of age) have the highest incidence of status epilepticus (SE). Because of their general health, elderly individuals are much more likely than younger (<60 years of age) persons to have more severe consequences from seizures. The incidence of SE is 15.5/100 000 in the 60-69 age group, 21.5/100 000 in the 70-79 age group and 25.9/100 000 in persons 80 and older. The most common cause in the elderly is acute symptomatic, with stroke and hypoxia the most frequent. The overall mortality of SE is quite high and occurs early, often within the first few days, and is related to the cause, with mortality of more than 80% in persons with anoxia. Although the cause of SE is an important factor in mortality, the aging body and brain may contribute to an unfavorable outcome. Treatment in the elderly is essentially the same as in younger adults with benzodiazepines (lorazepam, diazepam, clonazepam) and longer acting antiseizure drugs (phenytoin, fosphenytoin, valproate, levetiracetam, and lacosamide. At this time there are no evidence-based studies regarding Axis 2 (etiology) and Axis 4 (age). All current interventions for SE involve antiseizure drugs that were developed for treatment of chronic epilepsy. Treatments should be developed that are more specific for the various etiologies and involve drugs that work on the underlying cause of the SE.

Prognosis of status epilepticus in elderly patients

PURPOSE

To evaluate the clinical features and prognosis of status epilepticus (SE) in patients above 70 years old.

METHODS

Retrospective analysis of all patients ≥70 years old with SE registered prospectively during 4 years. Follow-up after discharge was performed.

RESULTS

Ninety patients were evaluated. Acute symptomatic etiology was the most prevalent. The mean number of antiepileptic drugs (AEDs) used was 2.7 ± 1.2, and 21% of the patients required sedation. A poor outcome was considered when death (31.1%) or developing of new neurological impairment at discharge (32.2%) occurred. After multivariate analysis, four variables predicted a poor outcome: acute symptomatic etiology (OR: 6.320; 95% CI: 1.976-20.217; P = .002), focal motor SE type (OR: 9.089; 95% CI: 2.482-33.283; P = .001), level of consciousness (OR: 4.596; 95% CI: 1.903-11.098; P = .001), and SE duration >12 hours (OR: 3.763; 95% CI: 1.130-12.530; P = .031). Independent predictive factors of mortality were SE duration >12 hours (OR: 4.306; 95% CI: 1.044-17.757; P = .043), modified Status Epilepticus Severity Score (mSTESS) (OR: 2.216; 95% CI: 1.313-3.740; P = .003), and development of complications (OR: 3.334; 95% CI: 1.004-11.070, P = .049). Considering long-term mortality, age (HR 1.036; 95% CI 1.001-1.071; P = .044), a potentially fatal underlying cause (HR 2.609; 95% CI 1.497- 4.548; P = .001), and mSTESS score >4 (HR 1.485; 95% CI 1.158-1.903; P = .002) remained as predictive factors. There was no association between sedation and the number of AEDs used with outcome at discharge or long-term mortality (P > .05).

CONCLUSIONS

SE above 70 years old has a high morbimortality. Prognosis is not related to treatment aggressiveness.

Hypothermia for Neuroprotection in Convulsive Status Epilepticus

BACKGROUND

Convulsive status epilepticus often results in permanent neurologic impairment. We evaluated the effect of induced hypothermia on neurologic outcomes in patients with convulsive status epilepticus.

METHODS

In a multicenter trial, we randomly assigned 270 critically ill patients with convulsive status epilepticus who were receiving mechanical ventilation to hypothermia (32 to 34°C for 24 hours) in addition to standard care or to standard care alone; 268 patients were included in the analysis. The primary outcome was a good functional outcome at 90 days, defined as a Glasgow Outcome Scale (GOS) score of 5 (range, 1 to 5, with 1 representing death and 5 representing no or minimal neurologic deficit). The main secondary outcomes were mortality at 90 days, progression to electroencephalographically (EEG) confirmed status epilepticus, refractory status epilepticus on day 1, "super-refractory" status epilepticus (resistant to general anesthesia), and functional sequelae on day 90.

RESULTS

A GOS score of 5 occurred in 67 of 138 patients (49%) in the hypothermia group and in 56 of 130 (43%) in the control group (adjusted common odds ratio, 1.22; 95% confidence interval [CI], 0.75 to 1.99; P=0.43). The rate of progression to EEG-confirmed status epilepticus on the first day was lower in the hypothermia group than in the control group (11% vs. 22%; odds ratio, 0.40; 95% CI, 0.20 to 0.79; P=0.009), but there were no significant differences between groups in the other secondary outcomes. Adverse events were more frequent in the hypothermia group than in the control group.

CONCLUSIONS

In this trial, induced hypothermia added to standard care was not associated with significantly better 90-day outcomes than standard care alone in patients with convulsive status epilepticus. (Funded by the French Ministry of Health; HYBERNATUS ClinicalTrials.gov number, NCT01359332 .).