The cost-effectiveness of a real-time seizure detection application for people with epilepsy.

OBJECTIVES: Automated seizure detection modalities can increase safety among people with epilepsy (PWE) and reduce seizure-related anxiety. We evaluated the potential cost-effectiveness of a seizure detection mobile application for PWE in Singapore. METHODS: We used a Markov cohort model to estimate the expected changes to total costs and health outcomes from a decision to adopt the seizure detection application versus the current standard of care from the health provider perspective. The time horizon is ten years and cycle duration is one month. Parameter values were updated from national databases and published literature. As we do not know the application efficacy in reducing seizure-related injuries, a conservative estimate of 1% reduction was used. Probabilistic sensitivity analysis, scenario analyses, and value of information analysis were performed. RESULTS: At a willingness-to-pay of $45,000/ quality-adjusted life-years (QALY), the incremental cost-effectiveness ratio was $1,096/QALY, and the incremental net monetary benefit was $13,656. Probabilistic sensitivity analyses reported that the application had a 99.5% chance of being cost-effective. In a scenario analysis in which the reduction in risk of seizure-related injury was 20%, there was a 99.8% chance that the application was cost-effective. Value of information analysis revealed that health utilities was the most important parameter group contributing to model uncertainty. CONCLUSIONS: This early-stage modeling study reveals that the seizure detection application is likely to be cost-effective compared to current standard of care. Future prospective trials will be needed to demonstrate the real-world impact of the application. Changes in health-related quality of life should also be measured in future trials.

Ictal and interictal EEG patterns in patients with nonconvulsive and subtle convulsive status epilepticus.

BACKGROUND: Electroencephalography findings in nonconvulsive or subtle convulsive status epilepticus (NCSE and SCSE, respectively) can be heterogenous. We aimed to study the different patterns on EEG in our cohort of patients. OBJECTIVE: Our objective was to study ictal and interictal EEG patterns in patients with NCSE and SCSE. METHODS: From January 2012 to December 2013, EEGs recorded from patients admitted for altered mental status suspected of having NCSE or SCSE were reviewed retrospectively. Electroencephalography status was defined as having (a) continuous ictal discharges lasting >5 min or (b) >2 discrete bursts of ictal discharges, each lasting <5 min, without returning to previous background rhythm in between these bursts. RESULTS: Among 1698 EEGs recorded for at least 30 min from hospitalized patients, 55 (3.23%) satisfied the criteria of EEG SE. The ictal onset was regional in 37 (67.2%) EEGs, multiregional independent in 8 (14.5%), and generalized in 10 (18.4%). The EEG seizure duration was >5 min in 24 (43.6%) EEGs, between 1 and 5 min in 14 (25.4%), and less than 1 min in 17 (30.8%). Twenty (36.3%) EEGs showed one continuous prolonged seizure episode of >5-minute duration, 15 (27.2%) had 10 or less discrete episodes, 20 (36.3%) had more than 10 episodes, and 11 (20%) had 2 or more ictal patterns. Thirty (54.5%) EEGs had onset ictal frequency of >8 Hz whereas the rest had <8-Hz ictal frequency. In the interictal segment, 29 patients had continuous generalized slow waves, while 12 had intermittent generalized slow waves. Eleven patients had continuous slow waves lateralized to one hemisphere, and these were ipsilateral to the ictal focus in 10 but contralateral in 1. Other interictal waves seen were PLEDS (6), sharp waves (3), suppression (5), and triphasic waves (1). The background alpha rhythm was absent in 36 patients and slow in 14, and normal background alpha was seen in the interictal period in 5 patients. CONCLUSION: The ictal and interictal EEG patterns in NCSE and SCSE can be varied. Further study to look for etiologic and clinical correlates of each pattern could add to its clinical value. This article is part of a Special Issue entitled "Status Epilepticus".

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.

Central pontine myelinolysis presenting as isolated sixth nerve palsy in third trimester of pregnancy.

A 30-year-old primigravida presented with isolated left sixth nerve palsy at 38 weeks gestation. Her MRI showed a lesion consistent with central pontine myelinolysis (CPM). Extensive investigations did not reveal any secondary cause for the CPM. She recovered spontaneously in 2 weeks with complete resolution of her MRI changes. To our knowledge, this is the first report of CPM occurring in third trimester in the absence of identifiable secondary causes and of CPM presenting as an isolated sixth nerve palsy. We discuss the reported causes of CPM in pregnancy, possible pathophysiologic mechanisms involved and the anatomic basis of the unique clinical presentation of sixth nerve palsy in our case.