Falling status epilepticus mortality rates in England and Wales: 2001-2013?

Characterization and quantification of epilepsy patients with hospital episodes in Portugal: A multicenter retrospective study from Liga Portuguesa Contra a Epilepsia

INTRODUCTION

Epilepsy affects around 50 million people worldwide and is associated with lower quality of life scores, an increased risk of premature death, and significant socio-economic implications. The lack of updated evidence on current epidemiology and patient characterization creates considerable uncertainty regarding the epilepsy burden in Portugal. The study aims to characterize and quantify the epilepsy patients who have been hospitalized, with medical or surgical procedures involved, and to analyze their associated comorbidities and mortality rates.

METHODS

A multicenter retrospective study was conducted using hospital production data of epilepsy patients. The study included all patients diagnosed with epilepsy-related International Classification of Diseases-9/10 codes between 2015 and 2018 in 57 Portuguese National Health Service (NHS) hospitals (n = 57 institutions). Patient characterization and quantification were done for all patients with an epilepsy diagnosis, with specific analyses focusing on those whose primary diagnosis was epilepsy. Baseline, demographic, and clinical characteristics were analyzed using descriptive statistics.

RESULTS

Between 2015 and 2018, a total of 80,494 hospital episodes (i.e., patient visit that generates hospitalization and procedures) were recorded, with 18 % to 19 % directly related to epilepsy. Among these epilepsy-related hospital episodes, 13.0 % led to short term hospitalizations (less than 24 h). Additionally, the average length of stay for all these epilepsy-related episodes was 8 days. A total of 49,481 patients were identified with epilepsy based on ICD-9/10 codes. The median age of patients was 64 years (min: 0; max: 104), with a distribution of 4.8 patients per 1,000 inhabitants. From the total of deaths (9,606) between 2015 and 2018, 14% were associated with patients whose primary diagnosis was epilepsy, with 545 of these being epilepsy-related deaths. Among patients with a primary diagnosis of epilepsy, the most common comorbidities were hypertension (24%) and psychiatric-related or similar comorbidities (15%), such as alcohol dependance, depressive and major depressive disorders, dementia and other convulsions.

CONCLUSION

This study showed similar results to other European countries. However, due to methodological limitations, a prospective epidemiological study is needed to support this observation. Furthermore, the present study provides a comprehensive picture of hospitalized epilepsy patients in Portugal, their comorbidities, mortality, and hospital procedures.

Mortality, and life expectancy in Epilepsy and Status epilepticus-current trends and future aspects

Patients with epilepsy carry a risk of premature death which is on average two to three times higher than in the general population. The risk of death is not homogenously distributed over all ages, etiologies, and epilepsy syndromes. People with drug resistant seizures carry the highest risk of death compared to those who are seizure free, whose risk is similar as in the general population. Most of the increased risk is directly related to the cause of epilepsy itself. Sudden unexplained death in epilepsy patients (SUDEP) is the most important cause of epilepsy-related deaths especially in the young and middle-aged groups. Population based studies with long-term follow up demonstrated that the first years after diagnosis carry the highest risk of death, while in the later years the mortality decreases. Improved seizure control and being exposed to a specialized comprehensive care centre may help to reduce the risk of death in patients with epilepsy. The mortality of status epilepticus is substantially increased with case fatality rates between 4.6% and 39%, depending on its cause and duration, and the age of the population studied. The epidemiological data on overall and cause specific mortality as well as their determinants and risk factors are critically reviewed and methodological issues pertinent to the studies on mortality of epilepsy and Status epilepticus are discussed.

Has the mortality of status epilepticus changed over the past few decades?

Earlier and more aggressive treatment of status epilepticus has long been established orthodoxy. In addition to increasing therapeutic options, it is of critical importance to understand whether or not this has translated into improved prognosis. In this review, we examine the evidence as to whether the mortality of convulsive status epilepticus changed over the past few decades. In particular, we discuss a recent systematic review and meta-analysis examining this question and its implications. We discuss potential reasons why there is no evidence of improved prognosis in terms of mortality and ways in which this may be addressed. Finally, we advocate the urgent need for accurate data on functional outcomes in non-fatal cases of status epilepticus. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Educational inequalities in epilepsy mortality in the Baltic countries and Finland in 2000-2015

Little is known about socioeconomic differences in epilepsy mortality. This study examined educational inequalities in epilepsy mortality in the general population in the Baltic countries and Finland in 2000-2015. Education-specific mortality estimates for individuals aged 30-74 in Estonia, Latvia and Lithuania were obtained from census-linked mortality datasets while data for Finland came from the register-based population and death data file of Statistics Finland. Trends and educational inequalities in epilepsy mortality were assessed using age-standardised mortality rates (ASMRs) per 100,000 person years and age-adjusted mortality rate ratios (RRs) calculated using Poisson regression. ASMRs were higher in men than women in all countries. ASMRs reduced in 2000-2015 among all men and women except for Finnish women. Among men, an inverse educational gradient in epilepsy mortality in 2000-2007 widened in 2008-2015 with ASMRs falling among high and mid educated men in all countries but increasing among low educated men in three countries. An inverse educational gradient in female mortality remained in all countries throughout 2000-2015. Although epilepsy mortality fell in the Baltic countries and Finland (men only) in 2000-2015, this masked a clear inverse educational gradient in mortality that became steeper across the period.

Frequency and Types of Complications Encountered in Patients With Nonconvulsive Status Epilepticus in the Neurological ICU: Impact on Outcome

Objectives. The frequency and types of complications in patients with nonconvulsive status epilepticus (NCSE) who are followed up in the intensive care unit (ICU), and the impact of these complications on outcome are not well-known. We investigated the complications and their effects on prognosis in NCSE patients. Methods. After reviewing the video-EEG monitoring (VEEGM) reports of all the consecutive patients who were followed up in our ICU between 2009 and 2019, we identified two groups of patients: 1-patients with NCSE (study group) and 2-patients who underwent VEEGM for possible NCSE but did not have ictal recordings (no-NCSE group). Electronic health records were reviewed to identify demographic and clinical data, duration of ICU care, medical and surgical complications, pharmacologic treatment, and outcome. These parameters were compared statistically between the groups. We also investigated the parameters affecting prognosis at discharge. Results. Thirty-two patients with NCSE comprised the study group. Infection developed in 84%. More than half were intubated, had tracheostomy or percutaneous endoscopic gastrostomy application. Refractory NCSE was associated with significantly more frequent complications and worse outcome. There was a higher tendency of infections in the study group (P = .059). Higher organ failure scores and prolonged stay in ICU predicted worse outcome (P < .05). Conclusion. The frequency of complications in patients with NCSE who are cared for in the ICU is considerable. Most of the complications are similar to the other patients in ICU, except for the higher frequency of infections. Increased physician awareness about modifiable parameters and timely interventions might help improve prognosis.

Seizure-Induced Oxidative Stress in Status Epilepticus: Is Antioxidant Beneficial?

Epilepsy is a common neurological disorder which affects patients physically and mentally and causes a real burden for the patient, family and society both medically and economically. Currently, more than one-third of epilepsy patients are still under unsatisfied control, even with new anticonvulsants. Other measures may be added to those with drug-resistant epilepsy. Excessive neuronal synchronization is the hallmark of epileptic activity and prolonged epileptic discharges such as in status epilepticus can lead to various cellular events and result in neuronal damage or death. Unbalanced oxidative status is one of the early cellular events and a critical factor to determine the fate of neurons in epilepsy. To counteract excessive oxidative damage through exogenous antioxidant supplements or induction of endogenous antioxidative capability may be a reasonable approach for current anticonvulsant therapy. In this article, we will introduce the critical roles of oxidative stress and further discuss the potential use of antioxidants in this devastating disease.

Clinical outcomes and treatments effectiveness in status epilepticus resolved by antiepileptic drugs: A five-year observational study

Objective

To evaluate clinical outcomes and treatment effectiveness of status epilepticus finally resolved by nonbenzodiazepine antiepileptic drugs (AEDs).

Methods

All consecutive SE episodes observed from September 1, 2013, to September 1, 2018, and resolved by AEDs were considered. Diagnosis and classification of SE followed the 2015 ILAE proposal. Nonconvulsive status (NCSE) diagnosis was confirmed according to the Salzburg EEG criteria. The modified Rankin Scale and deaths at 30 days from onset were used to evaluate outcomes.

Results

A total of 277 status episodes (mean age 71 years; 61% female) were treated and resolved by antiepileptic drugs after 382 treatment trials. 68% of the SE resolved after AED use as first/second treatment line, while subsequent trials with AEDs gave an additional 32% resolution. A return to baseline conditions was observed in 48% of the patients, while overall mortality was 19% without significant changes across the study years. Mortality was higher in NCSE than in convulsive SE (22.5% vs 12.9%; P < .05), while mortality did not differ in SE episodes resolved by a first/second AED trial (17.2%) versus SE resolved by successive treatment trials (18.9%). The resolution rate of intravenous AEDs was 82% for valproate, 77% for lacosamide, 71% for phenytoin, and 62% for levetiracetam. No significant differences were found in head-to-head comparison, but for the valproate-levetiracetam one that was related to NCSE episodes in which valproate resulted to be effective in 86% of the trials while levetiracetam in 62% (P < .002).

Significance

A high short-term mortality, stable over time, was observed in SE despite resolution of seizures, especially in SE with nonconvulsive semiology. Comparative AED efficacy showed no significant differences except for higher resolution rate for valproate versus levetiracetam in NCSE.

In-hospital mortality of status epilepticus in China: Results from a nationwide survey

PURPOSE

We attempted to determine the nationwide in-hospital mortality rate in people with status epilepticus (SE) in China.

METHODS

Using the database of the Chinese Hospital Quality Monitoring System (HQMS), we identified people hospitalised from 2013 to 2017 with an ICD-10 code G41 for SE as the primary diagnosis. HQMS was developed by the National Health Commission of the People's Republic of China. Demographics, outcomes at discharge, and financial information were extracted automatically from the medical records.

RESULTS

We identified 29,031 cases with SE as the primary diagnosis from 585 tertiary centres during the five-year period. Among those included, there was a preponderance of men (61 %), and the mean age was 40.4 ± 25.2 years (range: 0-98). The in-hospital mortality rate was 1.46 % over the whole time period, while the overall mortality ranged from 1.80 % in 2013 to 1.20 % in 2017. The mean cost of treatment was 14517.81 RMB ($ 2147.92) per individual, and the mean duration of hospital stay was 9.25 days.

CONCLUSION

We provide an overview of mortality related to SE in China as the HQMS database covers a large number of cases of SE in China, making it one of the most efficient tools for mortality investigation. The use of electronic medical records in China creates several challenges and here we discuss lessons learned. The methodology will be improved and will be used in future studies.

Admission patterns and survival from status epilepticus in critical care in the UK: an analysis of the Intensive Care National Audit and Research Centre Case Mix Programme database

BACKGROUND AND PURPOSE

Factors influencing the outcome after the critical care unit (CCU) for patients with status epilepticus (SE) are poorly understood. Survival for these patients was examined to establish (i) whether the risk of mortality has changed over time and (ii) whether admission to different unit types affects mortality risk over and above other risk factors.

METHODS

The Intensive Care National Audit and Research Centre database and the Case Mix Programme database (January 2001 to December 2016) were analysed. Units were defined as neuro-CCU (NCCU), general CCU with 24-h neurological support (GCCU-N) or general CCU with limited neurological support (GCCU-L).

RESULTS

There were 35 595 CCU cases of SE with a 3-fold increase over time (4739 in 2001-2004 to 14 166 in 2013-2016). More recent admissions were older and were more often unsedated on admission. Mortality declined for all units although this was more marked for NCCUs (8.1% in 2001-2004 to 4.4% in 2013-2016 compared to 5.1% and 4.1% for GCCU-L). Acute hospital mortality was two to three times higher than CCU mortality although this has also declined with time. GCCU-L appeared to have lower mortality than NCCUs (odds ratio 0.84, 95% confidence interval 0.72, 0.98) but after post hoc adjustment for case mix there were no differences. Older age and markers of seriousness of morbidity were all associated with increased mortality risk.

CONCLUSIONS

The number of patients admitted to a CCU for SE is rising but critical care and acute hospital mortality is decreasing. Patients treated in an NCCU have higher mortality but this is explicable by more severe underlying disease.

Change in Mortality of Generalized Convulsive Status Epilepticus in High-Income Countries Over Time: A Systematic Review and Meta-analysis

Importance

Status epilepticus (SE) is associated with significant morbidity and mortality. Since the late 1990s, a more aggressive management of prolonged convulsive seizures lasting longer than 5 minutes has been advocated.

Objective

To determine if convulsive SE mortality has decreased during a time of increasing advocacy for out-of-hospital treatment and escalating and earlier treatment protocols for prolonged seizures and SE.

Data Source

This systemic review and meta-analysis on studies focused on the mortality of convulsive status epilepticus was conducted by searching MEDLINE, Embase, PsychINFO, CINAHL Plus, and the Cochrane Database of Systematic Reviews between January 1, 1990, and June 30, 2017.

Study Selection

Studies were excluded if they had fewer than 30 participants (<20 for refractory SE), were limited to SE of single specific etiology or an evaluation of a single treatment modality, or were studies of nonconvulsive SE.

Data Extraction and Synthesis

Data were abstracted and their quality was assessed via a modified Newcastle-Ottawa scale independently by 2 reviewers (A.N. and T.D.G.) using the Meta-analyses of Observational Studies in Epidemiology (MOOSE) guidelines. Data were pooled using a random-effects model.

Main Outcomes and Measures

The main outcome measure was in-hospital mortality or 30-day case fatality expressed as proportional mortality.

Results

Sixty-one studies were included in the analysis. The pooled mortality ratios were 15.9% (95% CI, 12.7-19.2) for adult studies, 13.0% (95% CI, 7.2-19.0) for all-age population studies, 3.6% (95% CI, 2.0%-5.2%) for pediatric studies, and 17.3% (95% CI, 9.8-24.7) for refractory SE studies, with very high between-study heterogeneity. We found no evidence of a change in prognosis over time nor by the definition of SE used.

Conclusions and Relevance

The mortality of convulsive SE is higher in adults than in children and there was no evidence for improved survival over time. Although there are many explanations for these findings, they can be explained by aetiology of SE being the major determinant of mortality. However, there are potential confounders, including differences in case ascertainment and study heterogeneity. This meta-analysis highlights the need for strict international guidelines for the study of this condition.

Status epilepticus in Auckland, New Zealand: Incidence, etiology, and outcomes

OBJECTIVE

To determine the incidence, etiology, and outcome of status epilepticus (SE) in Auckland, New Zealand, using the latest International League Against Epilepsy (ILAE) SE semiological classification.

METHODS

We prospectively identified patients presenting to the public or major private hospitals in Auckland (population = 1.61 million) between April 6, 2015 and April 5, 2016 with a seizure lasting 10 minutes or longer, with retrospective review to confirm completeness of data capture. Information was recorded in the EpiNet database.

RESULTS

A total of 477 episodes of SE occurred in 367 patients. Fifty-one percent of patients were aged <15 years. SE with prominent motor symptoms comprised 81% of episodes (387/477). Eighty-four episodes (18%) were nonconvulsive SE. Four hundred fifty episodes occurred in 345 patients who were resident in Auckland. The age-adjusted incidence of 10-minute SE episodes and patients was 29.25 (95% confidence interval [CI] = 27.34-31.27) and 22.22 (95% CI = 20.57-23.99)/100 000/year, respectively. SE lasted 30 minutes or longer in 250 (56%) episodes; age-adjusted incidence was 15.95 (95% CI = 14.56-17.45) SE episodes/100 000/year and 12.92 (95% CI = 11.67-14.27) patients/100 000/year. Age-adjusted incidence (10-minute SE) was 25.54 (95% CI = 23.06-28.24) patients/100 000/year for males and 19.07 (95% CI = 16.91-21.46) patients/100 000/year for females. The age-adjusted incidence of 10-minute SE was higher in Māori (29.31 [95% CI = 23.52-37.14]/100 000/year) and Pacific Islanders (26.55 [95% CI = 22.05-31.99]/100 000/year) than in patients of European (19.13 [95% CI = 17.09-21.37]/100 000/year) or Asian/other descent (17.76 [95% CI = 14.73-21.38]/100 000/year). Seventeen of 367 patients in the study died within 30 days of the episode of SE; 30-day mortality was 4.6%.

SIGNIFICANCE

In this population-based study, incidence and mortality of SE in Auckland lie in the lower range when compared to North America and Europe. For pragmatic reasons, we only included convulsive SE if episodes lasted 10 minutes or longer, although the 2015 ILAE SE classification was otherwise practical and easy to use.

The reliable measurement of temporal trends in mortality attributed to epilepsy and status epilepticus in Northern Ireland between 2001-2015

PURPOSE

Epilepsy mortality is of considerable public health concern, as a leading cause of premature neurological death. Recent English and Welsh mortality data suggests a falling mortality rate where epilepsy was the underlying cause of death, predominantly due to a reduction in status epilepticus (SE) mortality. We sought to validate this finding in Northern Ireland.

METHODS

Officially recorded death certificate data related to epilepsy and SE were obtained from the Northern Ireland statistics and research agency. Data were analysed from 2001 to 2015. The outcomes were the age-adjusted mortality rate for epilepsy and SE. External validation of SE deaths was carried out using data from an intensive care national audit and research centre database.

RESULTS

From 2001 until end of 2015, epilepsy was recorded at death certification in 1484 cases. 458 deaths were considered due to epilepsy. Among 75 in whom SE was recorded, SE was the cause of death in 46 patients. External validation found 103 total deaths related to SE in ICU departments in Northern Ireland, suggesting an overall under-ascertainment of officially recorded statistics. With respect to the 2013 European Standard Population, the mean age-adjusted mortality rate for epilepsy was 1.9 (95% C.I. 1.73-2.07) per 100,000 person years. For SE the mean age-adjusted mortality rate was 2.1 (95% C.I. 0.15-0.27) per 100,000 person years.

CONCLUSIONS

Death certification in SE is likely to be an underestimate of the reality. Further efforts are urgently needed to determine the extent of SE-related deaths and all deaths in patients with epilepsy.

Pathophysiology of status epilepticus

Status epilepticus (SE) is the maximal expression of epilepsy with a high morbidity and mortality. It occurs due to the failure of mechanisms that terminate seizures. Both human and animal data indicate that the longer a seizure lasts, the less likely it is to stop. Recent evidence suggests that there is a critical transition from an ictal to a post-ictal state, associated with a transition from a spatio-temporally desynchronized state to a highly synchronized state, respectively. As SE continues, it becomes progressively resistant to drugs, in particular benzodiazepines due partly to NMDA receptor-dependent internalization of GABA(A) receptors. Moreover, excessive calcium entry into neurons through excessive NMDA receptor activation results in activation of nitric oxide synthase, calpains, and NADPH oxidase. The latter enzyme plays a critical part in the generation of seizure-dependent reactive oxygen species. Calcium also accumulates in mitochondria resulting in mitochondrial failure (decreased ATP production), and opening of the mitochondrial permeability transition pore. Together these changes result in status epilepticus-dependent neuronal death via several pathways. Multiple downstream mechanisms including inflammation, break down of the blood-brain barrier, and changes in gene expression can contribute to later pathological processes including chronic epilepsy and cognitive decline.