Ketonuria and Seizure Control in the Medium Chain Triglyceride and Classic Ketogenic Diets.

We hypothesized that children receiving medium-chain triglyceride ketogenic diet (MCTKD) experience similar seizure reduction despite lower ketosis compared with classic ketogenic diet (CKD). Children initiating CKD or MCTKD were enrolled in a prospective observational study. Forty-five children completed 6 months of KD (n = 17 MCTKD, n = 28 CKD). The proportion achieving ≥50% seizure reduction was 71% CKD group and 59% MCTKD group; ≥90% reduction was 32% and 36% in CKD and MCTKD groups, respectively. CKD had higher urine ketones (≥8 mmol/L: 79% vs. 36%, p = 0.005). Children receiving MCTKD experience similar seizure control to CKD despite lower urine ketone measures.

Autopsy-reported cause of death in a population-based cohort of sudden unexpected death in epilepsy.

OBJECTIVE: Sudden unexpected death in epilepsy (SUDEP) is a diagnosis of exclusion; the definition includes individuals with epilepsy who die suddenly without an identifiable toxicological or anatomical cause of death. Limited data suggest underidentification of SUDEP as the cause of death on death certificates. Here, we evaluate the autopsy-reported cause of death in a population-based cohort of SUDEP cases. METHODS: Case summaries of forensic autopsies conducted in Ontario, Canada between January 2014 and June 2016 were retrospectively screened using a language processing script for decedents with a history of epilepsy or seizures. After manual review for potential SUDEP cases, two neurologists independently examined the autopsy reports and classified deaths by Nashef criteria. Demographic characteristics and consideration by the forensic pathologist of the role of epilepsy, seizure, and SUDEP in death were summarized. RESULTS: One hundred and eight Definite, 34 Definite Plus, and 22 Possible SUDEP cases were identified. Seventy-five percent of Definite/Definite Plus SUDEP cases identified by the neurologists were attributed to SUDEP, epilepsy, or seizure disorder in the autopsy report. There was a significant association between the proportion of cases listed in the autopsy report as SUDEP, epilepsy, or seizure disorder and neurologists' SUDEP classification (86% of Definite, 38% of Definite Plus, 0% of Possible). Age was significantly associated with SUDEP classification; Definite cases were younger than Definite Plus, which were younger than Possible SUDEP cases. SIGNIFICANCE: Most SUDEP cases identified by neurologists were classified concordantly by forensic pathologists in Ontario, Canada; however, concordance decreased with increased case complexity. Although the role of epilepsy/seizures was considered in most Definite/Definite Plus cases, this study highlights the need for autopsy report review of potential SUDEP cases in research studies and assessments of the public health burden of SUDEP. The relationship between age and SUDEP classification has important public health implications; SUDEP incidence may be underappreciated in older adults.

Inhibition in the face of emotion: Characterization of the spatial-temporal dynamics that facilitate automatic emotion regulation.

Emotion regulation mediates socio-cognitive functions and is essential for interactions with others. The capacity to automatically inhibit responses to emotional stimuli is an important aspect of emotion regulation; the underlying neural mechanisms of this ability have been rarely investigated. Forty adults completed a Go/No-go task during magnetoencephalographic (MEG) recordings, where they responded rapidly to either a blue or purple frame which contained angry or happy faces. Subjects responded to the target color in an inhibition (75% Go trials) and a vigilance condition (25% Go trials). As expected, inhibition processes showed early, sustained activation (200-450 ms) in the right inferior frontal gyrus (IFG). Emotion-related inhibition processes showed greater activity with angry faces bilaterally in the orbital-frontal gyri (OFG) starting at 225 ms and temporal poles from 250 ms, with right hemisphere dominance. The presence of happy faces elicited earlier activity in the right OFG. This study demonstrates that the timing of inhibition processes varies with the emotional context and that there is much greater activation in the presence of angry faces. It underscores the importance of the right IFG for inhibition processes, but the OFG in automatic emotion regulation.

Effectiveness of antiepileptic drug tapering in the pediatric epilepsy monitoring unit.

OBJECTIVE: Limited evidence on the relationship between antiepileptic drug (AED) tapering and the likelihood of a seizure during an Epilepsy Monitoring Unit (EMU) admission is available, and no evidence specific to the pediatric population has been published. Our study sought to determine whether AED tapering leads to increased seizure likelihood in a pediatric EMU setting. METHODS: We performed a retrospective chart review of children admitted to the pediatric EMU at the Hospital for Sick Children in Toronto between June 1, 2014 and June 1, 2016. Data collected included demographics, reason for EMU referral, and epilepsy and medical characteristics. Among those with nondaily seizures, Kaplan-Meier curves were fit to compare probability of EMU seizure in those who were tapered fully from at least one AED to those not tapered. A Cox proportional hazards model was fit to evaluate this relationship after adjustment for subject sex, distance traveled to hospital, epilepsy duration, seizure frequency, time since last seizure, whether EMU referral was part of presurgical planning, magnetic resonance imaging (MRI) findings, and number of prescribed AEDs. An interaction between medication taper and number of prescribed AEDs was also included. Terms not significant at p < 0.3 were removed from the model, and the reduced model was recomputed. RESULTS: Of the 281 children included in the study, 159 had nondaily seizures. Kaplan-Meier curves indicated fully tapering at least one AED was associated with increased likelihood of seizure during EMU; however, after adjustment for confounding variables, this association was not preserved. Abnormal MRI findings, referral for presurgical evaluation, and shorter (≤3 months) time since last seizure were associated with increased likelihood of seizure during EMU. SIGNIFICANCE: Short-term AED tapering in pediatric patients may not be effective for increasing seizure likelihood in the EMU.

Mental flexibility: An MEG investigation in typically developing children.

Mental flexibility is a core property of cognitive executive functions, relying on an extended frontoparietal network in the brain. fMRI research comparing typically developing children and adults has found that children from an early age recruit the same "classic" brain areas associated with mental flexibility as adults; however, there is evidence that the timing of activation may be different. To investigate the temporal dynamics of brain activity associated with mental flexibility in children, we recruited 22 typically developing children (8-15 years) to complete a set-shifting task in the MEG. Our results showed that while the children relied on the same frontoparietal network of mental flexibility, there was a different emphasis on active brain regions, with children preferentially using their posterior parietal cortices. Additional areas such as the temporal pole and the premotor areas were also recruited, potentially playing a supporting role. Although children shared the same window of peak activity as adults, 75-350ms, we found a significant decrease in activation latency with increasing age, suggesting the presence of developmental differences in timing of brain activity in areas supporting mental flexibility during childhood.

Why child neurologists talk about SUDEP: Results from two cross-sectional surveys.

Objective: To characterize SUDEP discussion practices of child neurologists approximately 6 and 12 months after publication of the American Academy of Neurology SUDEP Clinical Practice Guideline and explore factors associated with discussion practice. Methods: Child Neurology Society members (~2450) were electronically surveyed in November 2017 and May 2018 regarding their practice of discussing SUDEP with patients with epilepsy or their caregivers. Multivariable proportional odds ordinal logistic regression evaluated factors associated with discussing SUDEP with a greater proportion of epilepsy patients/caregivers. Reasons for changing practice were described. Results: Among the 369 child neurologist respondents, 36% reported discussing SUDEP with at least half of their epilepsy patients/caregivers including 12% who discuss with all or almost all (>90%) of their epilepsy patients/families. Those who discussed SUDEP with an increased proportion of their patients were more likely to agree that they knew enough to talk about SUDEP, agree that healthcare providers have an ethical obligation to discuss SUDEP, and disagree that there is not enough time to talk about SUDEP. Those who agreed SUDEP could provoke excessive anxiety or worry were less likely to discuss SUDEP with an increased proportion of their patients. Reading the SUDEP Clinical Practice Guideline was a frequently cited reason among respondents who reported a recent change in discussion practice. Significance: Most child neurologists do not follow the current SUDEP Clinical Practice Guideline regarding SUDEP discussion. Feeling sufficiently knowledgeable and ethically obligated to discuss SUDEP were associated with increased discussion practice, suggesting an educational intervention may be effective at increasing SUDEP discussion rates.

Neutropenia in Children Treated With Ketogenic Diet Therapy.

OBJECTIVES: The objectives were to investigate the relationship between ketogenic diet therapy and neutropenia in children with epilepsy. METHODS: A retrospective chart review of children who initiated ketogenic diet at the Hospital for Sick Children between January 1, 2000, and May 1, 2018 was performed. Factors associated with the development of neutropenia during ketogenic diet therapy were evaluated and the relationship between development of a significant or suspected infection and neutrophil count was analyzed. RESULTS: One hundred two children met inclusion criteria and were followed on the diet for up to 24 months. Thirteen of 102 (13%) children were neutropenic at diet initiation. In the remaining 89 children, 27 developed neutropenia. Developing neutropenia was significantly associated with the ketogenic diet at 6 (13%), 12 (23%), and 24 (25%) months follow-up. Developing neutropenia was associated with higher urinary ketones (OR = 4.26, 95% CI: 1.27, 14.15) and longer duration of ketogenic diet therapy (OR = 3.29, 95% CI: 1.42, 7.96). There was no significant association between development of a clinically significant infection and neutropenia. CONCLUSION: Ketogenic diet therapy is associated with neutropenia in children with epilepsy, however, it does not have a significant clinical impact. Concern regarding neutropenia should not discourage the use of the ketogenic diet in children.

The spectrum of epilepsy in children with 15q13.3 microdeletion syndrome.

PURPOSE: To further define the epilepsy phenotype in a cohort of children with 15q13.3 microdeletion syndrome. METHODS: We retrospectively reviewed the phenotypic spectrum of all children aged < 18 years with epilepsy and 15q13.3 microdeletion syndrome. RESULTS: Thirteen children were included, 69% were female. The median age of children in the cohort was 12 years (age range: 3 years-15 years). Median age at seizure onset was 4 years. Eleven children (85%) had intellectual disability. Nine of 13 children (69%) had a history of typical absence seizures with median age of onset at 5 years (2 had absence status epilepticus). Thirty-one percent (4/13) had focal with impaired awareness non-motor onset seizures. ILAE recognized absence epilepsy syndromes were diagnosed in 6/13 (46%). The remainder were classified as having genetic generalized epilepsies with overlap clinical features, combined or focal epilepsies. Electroencephalogram in the cohort showed generalized (85%) and focal epileptiform discharges (62%) and posterior dominant rhythm slowing (33%). One child had electrical status epilepticus of sleep. Neuroimaging was performed in 5 children (38%) and revealed abnormal findings in 3. Seizures were drug resistant in a third of the cohort. Valproate resulted in seizure freedom in 5 (42%). Oxcarbazepine caused clinical worsening in one child with combined seizure types. Two children tried cannabidiol and one tried the ketogenic diet; neither was effective. CONCLUSIONS: The epilepsy phenotype in children with 15q13.3 microdeletion syndrome is defined by childhood onset absence seizures, and may have atypical features such as, early onset absences, persistence into adolescence, status epilepticus, intellectual disability and treatment resistance. Focal seizures and focal EEG findings may be observed and should be treated cautiously, given the possibility of combined seizure types. Valproate appeared effective, although other treatments must be explored further.

The influence of the number of part-set cues on order retention.

Across seven experiments, the present article examined the influence of the number of part-set cues on order retention, as assessed by both reconstruction of order and serial recall tests. Historically, part-set cueing facilitation occurs when half of the items are provided as valid part-set cues on tests of order memory. Using a variety of list lengths (10 or 16), numbers of cues (0-14), and types of cues (full or partial), the present experiments showed disparate effects of the number of part-set cues on reconstruction and serial recall tasks. On reconstruction tests, a minimum number of full cues was required before part-set cueing facilitation was produced and the magnitude of facilitation increased as the number of cues increased. Generally, partial cues did not influence order retention until almost the entire list was provided as partial cues. On serial recall tests, part-set cueing facilitation was only evident with a few full cues. In contrast, part-set cueing impairment was the norm when many partial cues were provided. These results were largely consistent with predictions of the retrieval strategy disruption hypothesis, as well as with an anchoring account of part-set cueing for order.

Temporal trends and autopsy findings of SUDEP based on medico-legal investigations in the United States.

OBJECTIVE: To determine time trends and distinguishing autopsy findings of sudden unexpected death in epilepsy (SUDEP) in the United States. METHODS: We identified decedents where epilepsy/seizure was listed as cause/contributor to death or comorbid condition on the death certificate among all decedents who underwent medico-legal investigation at 3 medical examiner (ME) offices across the country: New York City (2009-2016), San Diego County (2008-2016), and Maryland (2000-2016). After reviewing all available reports, deaths classified as definite/probable/near SUDEP or SUDEP plus were included for analysis. Mann-Kendall trend test was used to analyze temporal trends in SUDEP rate for 2009-2016. Definite SUDEPs were compared to sex- and age ±2 years-matched non-SUDEP deaths with a history of epilepsy regarding autopsy findings, circumstances, and comorbidities. RESULTS: A total of 1,086 SUDEP cases were identified. There was a decreasing trend in ME-investigated SUDEP incidence between 2009 and 2016 (z = -2.2, S = -42, p = 0.028) among 3 regions. There was a 28% reduction in ME-investigated SUDEP incidence from 2009 to 2012 to 2013-2016 (confidence interval, 17%-38%, p < 0.0001). We found no correlation between SUDEP rates and the month of year or day of week. There was no difference between SUDEP and non-SUDEP deaths regarding neurodevelopmental abnormalities, pulmonary congestion/edema, and myocardial fibrosis. CONCLUSIONS: There was a decreasing monotonic trend in ME-investigated SUDEP incidence over 8 years, with a 28% reduction in incidence from 2009-2012 to 2013-2016. Unlike SIDS and sudden cardiac death, we found no correlation between SUDEP and the season of year or day of week. No autopsy findings distinguished SUDEP from non-SUDEP deaths.

Magnetoencephalographic (MEG) brain activity during a mental flexibility task suggests some shared neurobiology in children with neurodevelopmental disorders.

BACKGROUND: Children with neurodevelopmental disorders (NDDs) exhibit a shared phenotype that involves executive dysfunctions including impairments in mental flexibility (MF). It is of interest to understand if this phenotype stems from some shared neurobiology. METHODS: To investigate this possibility, we used magnetoencephalography (MEG) neuroimaging to compare brain activity in children (n = 88; 8-15 years) with autism spectrum disorders (ASD), attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD), as they completed a set-shifting/mental flexibility task. RESULTS: Neuroimaging results revealed a similar parietal activation profile across the NDD, groups suggesting a link to their shared phenotype. Differences in frontal activity differentiated the three clinical groups. Brain-behaviour analyses showed a link with repetitive behaviours suggesting shared dysfunction in the associative loop of the corticostriatal system. CONCLUSION: Our study supports the notion that NDDs may exist along a complex phenotypic/biological continuum. All NDD groups showed a sustained parietal activity profile suggesting that they share a strong reliance on the posterior parietal cortices to complete the mental flexibility task; future studies could elucidate whether this is due to delayed brain development or compensatory functioning. The differences in frontal activity may play a role in differentiating the NDDs. The OCD group showed sustained prefrontal activity that may be reflective of hyperfrontality. The ASD group showed reduced frontal activation suggestive of frontal dysfunction and the ADHD group showed an extensive hypoactivity that included frontal and parietal regions. Brain-behaviour analyses showed a significant correlation with repetitive behaviours which may reflect dysfunction in the associative loop of the corticostriatal system, linked to inflexible behaviours.

Addressing the Language Binding Problem With Dynamic Functional Connectivity During Meaningful Spoken Language Comprehension.

During speech, how does the brain integrate information processed on different timescales and in separate brain areas so we can understand what is said? This is the language binding problem. Dynamic functional connectivity (brief periods of synchronization in the phase of EEG oscillations) may provide some answers. Here we investigate time and frequency characteristics of oscillatory power and phase synchrony (dynamic functional connectivity) during speech comprehension. Twenty adults listened to meaningful English sentences and non-sensical "Jabberwocky" sentences in which pseudo-words replaced all content words, while EEG was recorded. Results showed greater oscillatory power and global connectivity strength (mean phase lag index) in the gamma frequency range (30-80 Hz) for English compared to Jabberwocky. Increased power and connectivity relative to baseline was also seen in the theta frequency range (4-7 Hz), but was similar for English and Jabberwocky. High-frequency gamma oscillations may reflect a mechanism by which the brain transfers and integrates linguistic information so we can extract meaning and understand what is said. Slower frequency theta oscillations may support domain-general processing of the rhythmic features of speech. Our findings suggest that constructing a meaningful representation of speech involves dynamic interactions among distributed brain regions that communicate through frequency-specific functional networks.

Drowning in epilepsy: A population-based case series.

OBJECTIVES: The risk of drowning is reported to be 15-19 times greater in people with epilepsy compared to the general population. Despite this disproportionate burden, there is limited data about the circumstances surrounding drowning deaths in people with epilepsy. This population-based case series characterizes drowning deaths in people with epilepsy. METHODS: Postmortem data from coroner-ordered autopsies conducted in Ontario between 2014 and 2016 were screened for cases of drowning in people with a history of seizures. Demographic information, epilepsy characteristics, and circumstances surrounding death were extracted from post mortem reports. The incidence of drowning in people with epilepsy was calculated using government estimates of the Ontario population and the number of people with epilepsy. RESULTS: Twenty-five people with epilepsy drowned during the three-year study period, giving an estimated incidence of 1.5 per 10,000 epilepsy person-years (95% CI: 0.98, 2.23). Decedents were mostly young (mean age 36 years) and without physical or developmental disability. Approximately one-third had psychiatric comorbidities. Epilepsy severity ranged from well-controlled to drug refractory. Only 3 people had alcohol or illicit drugs detected on toxicological analysis. Forty-four percent of deaths were the result of an unwitnessed drowning in a bathtub. CONCLUSIONS: This population-based case series confirms people with epilepsy drown at a rate nearly ten times greater than the general population (1.5 per 10,000 epilepsy person-years compared to the estimated provincial average of 0.13 per 10,000). Drowning deaths in people with epilepsy most often occur in the bathtub. These deaths are only rarely associated with intoxication. People with epilepsy should receive counseling on the increased risk of drowning, including information regarding the significant risk associated with bathtub use, the potential protective roles of anti-epileptic drug (AED) adherence and supervision when in or around water, and the fact that all people with epilepsy remain at an increased risk of drowning regardless of their apparent seizure control.

Incidence of sudden unexpected death in epilepsy in children is similar to adults.

OBJECTIVE: To determine the incidence of sudden unexpected death in epilepsy (SUDEP) in children in Ontario, Canada. METHODS: Cases of suspected pediatric SUDEP occurring between January 1, 2014, and December 31, 2015, in Ontario, Canada, were eligible for inclusion. Potential cases were identified through 3 sources: a national pediatrician surveillance program, child neurologist report, and screening of provincial forensic autopsies. Cases were classified as definite, definite plus, probable, possible, and near/near plus according to criteria described by Nashef et al. (Epilepsia 2012). Overall crude pediatric SUDEP incidence and the incidence of definite or probable pediatric SUDEP were calculated using estimates of the prevalence of pediatric epilepsy in Canada drawn from government survey data and the number of children living in Ontario. Capture-recapture analysis was used to estimate the number of missing cases and determine an adjusted definite/probable SUDEP incidence. RESULTS: Seventeen cases of pediatric SUDEP resulted in an overall incidence of 1.17 (95% confidence interval 0.68-1.88) per 1,000 pediatric epilepsy person-years. The definite/probable incidence, including definite (n = 11), definite plus (n = 2), or probable (n = 3) SUDEP cases, was 1.11 (0.63-1.79). Capture-recapture analysis indicated an estimated 21 (16-39) definite/probable SUDEP cases occurred during the study period, giving an adjusted incidence of definite/probable SUDEP of 1.45 (0.90-2.22) per 1,000 pediatric epilepsy person-years. CONCLUSION: SUDEP may be more common in children than widely reported, with the incidence rate of definite/probable SUDEP in children being similar to rates reported in adults.

Water quality guidance for protection of freshwater mussels (Unionidae) from ammonia exposure.

Ammonia toxicity data for freshwater mussels (Unionidae), a significantly imperiled taxa, were used to derive estimates of concentrations that would not likely be harmful in acute and chronic exposures and to assess the protectiveness of current U.S. Environmental Protection Agency (U.S. EPA) water quality criteria to this family of organisms. Thirty acute (24-96-h) median lethal concentrations (LC50s), covering 10 species in eight unionid genera, were used to calculate genus mean acute values (GMAVs) ranging from 2.56 to 8.97 mg/L total ammonia as N at pH 8. Freshwater mussels are at the sensitive end of the range when added to the GMAVs from the database used to derive the U.S. EPA criteria maximum concentration (CMC). We derived two estimates of acute exposure water quality guidance for the protection of freshwater mussels (CMC(FM)) by a recalculation of the CMC after adding freshwater mussel GMAVs to the U.S. EPA data set. The CMC(FM)s of 1.75 and 2.50 mg/L total ammonia as N at pH 8 average 60% less than the U.S. EPA CMC of 5.62 mg/L total ammonia as N at pH 8 for application when salmonids are present. These values average about 75% less than the CMC for application when salmonids are absent. No chronic ammonia exposure data existed for unionids. Thus, we applied a range of estimated acute:chronic ratios to the acute toxicity data set, expanded with the freshwater mussel GMAVs. to estimate continuous ammonia concentrations that may be protective of freshwater mussels. These estimates ranged from 0.3 to 1.0 mg/L total ammonia as N at pH 8, about 20 to 75% less than the U.S. EPA criteria continuous concentration (CCC) of 1.24 mg/L total ammonia as N at pH 8 and 25 degrees C. The current numeric criteria for ammonia may not be protective of mussels, more than half of whose nearly 300 species are in decline in North America. While the CMC(FM) and CCC(FM) are not equivalent to revised U.S. EPA criteria, they are offered as interim guidance for the protection of freshwater mussels.