Climate change and epilepsy: Insights from clinical and basic science studies

Effects of ambient temperature on pediatric incident seizure: A case-crossover analysis using distributed lag non-linear models

OBJECTIVE

Emerging evidence supports that brain dysfunction may be attributable to environmental factors. This study aims to examine associations of ambient temperature and temperature variability (TV) with seizure incidence in children, which has not been explored.

MATERIAL AND METHODS

Data on 2718 outpatient visits due to seizure were collected in Shanghai, China, from 2018 to 2023. Exposure to ambient temperature was estimated at children's residential addresses using spatial-temporal models. A time-stratified case-crossover design with a distributed lag non-linear model (DLNM) was conducted to assess the association between seizure incidence and daily average of ambient temperature over a period of 21 days prior to a case date of disease onset. For a given case date, we selected all dates falling on the same day of the week within the same month as control dates. We calculated a composite index of intra-day and inter-day TV, which was the standard deviation of the daily minimum and maximum temperatures, respectively, over 7 days preceding a case date. We then assessed the association between TV and seizure incidence. Stratified analyses were conducted by age (73.51% < 5 years old and 26.49 % ≥ 5 years old), sex (41.83% female), presence of fever (69.72%), and diagnosis of epilepsy (27.63%).

RESULTS

We observed inversed J-shaped temperature-response curves. Lower temperatures had a significant and prolonged effect than higher temperatures. Using 20 °C (with the minimum effect) as the reference, the cumulative odds ratios (ORs) for over 0-21 days preceding the onset at the 5th percentile of the temperature (3 °C) and at the 95th percentile (29 °C) were 3.17 (95% CI: 1.77, 5.68) and 1.54 (95% CI: 0.97, 2.44), respectively. In addition, per 1 °C increases in TV0-7 was associated with OR of 1.08 (95% CI: 1.01, 1.15). Older children and those experiencing seizure with fever exhibited a higher risk of seizure onset at both lower and higher ambient temperatures.

CONCLUSION

Both low and high temperatures can contribute to the morbidity related to pediatric seizure. Lower temperatures, however, exerted a longer period of effect prior to seizure onset than higher temperatures. An increased risk for incident seizure was significantly associated with temperature variability during preceding 7 days.

The Influence of Climatic Factors on the Provocation of Epileptic Seizures

Background/Objectives: Recent studies provide the first indications of the impact of climate factors on human health, especially with individuals already grappling with internal and neurological conditions being particularly vulnerable. In the face of escalating climate change, our research delves into the specific influence of a spectrum of climatic factors and seasonal variations on the hospital admissions of patients receiving treatment for epileptic seizures at our clinic in Kaiserslautern. Methods: Our study encompassed data from 9366 epilepsy patients who were admitted to hospital due to epileptic seizures. We considered seven climate parameters that Germany's National Meteorological Service made available. We employed the Kruskal-Wallis test to examine the correlation between the frequency of admittance to our hospital in the mentioned patient group and seasons. Furthermore, we used conditional Poisson regression and distributed lag linear models (DLMs) to scrutinize the coherence of the frequency of patient admittance and the investigated climate parameters. The mentioned parameters were also analyzed in a subgroup analysis regarding the gender and age of patients and the classification of seizures according to ILAE 2017. Results: Our results demonstrate that climatic factors, such as precipitation and air pressure, can increase the frequency of hospital admissions for seizures in patients with general-onset epilepsy. In contrast, patients with focal seizures are less prone to climatic changes. Consequently, admittance to the hospital for seizures is less affected by climatic factors in the latter patient group. Conclusions: The present study demonstrated that climatic factors are possible trigger factors for the provocation of seizures, particularly in patients with generalized seizures. This was determined indirectly by analyzing the frequency of seizure-related emergency admissions and their relation to prevailing climate factors. Our study is consistent with other studies showing that climate factors, such as cerebral infarcts or cerebral hemorrhages, influence patients' health.

Virus-Induced Epilepsy vs. Epilepsy Patients Acquiring Viral Infection: Unravelling the Complex Relationship for Precision Treatment

The intricate relationship between viruses and epilepsy involves a bidirectional interaction. Certain viruses can induce epilepsy by infecting the brain, leading to inflammation, damage, or abnormal electrical activity. Conversely, epilepsy patients may be more susceptible to viral infections due to factors, such as compromised immune systems, anticonvulsant drugs, or surgical interventions. Neuroinflammation, a common factor in both scenarios, exhibits onset, duration, intensity, and consequence variations. It can modulate epileptogenesis, increase seizure susceptibility, and impact anticonvulsant drug pharmacokinetics, immune system function, and brain physiology. Viral infections significantly impact the clinical management of epilepsy patients, necessitating a multidisciplinary approach encompassing diagnosis, prevention, and treatment of both conditions. We delved into the dual dynamics of viruses inducing epilepsy and epilepsy patients acquiring viruses, examining the unique features of each case. For virus-induced epilepsy, we specify virus types, elucidate mechanisms of epilepsy induction, emphasize neuroinflammation's impact, and analyze its effects on anticonvulsant drug pharmacokinetics. Conversely, in epilepsy patients acquiring viruses, we detail the acquired virus, its interaction with existing epilepsy, neuroinflammation effects, and changes in anticonvulsant drug pharmacokinetics. Understanding this interplay advances precision therapies for epilepsy during viral infections, providing mechanistic insights, identifying biomarkers and therapeutic targets, and supporting optimized dosing regimens. However, further studies are crucial to validate tools, discover new biomarkers and therapeutic targets, and evaluate targeted therapy safety and efficacy in diverse epilepsy and viral infection scenarios.

Drug therapy problems and contributing factors among patients with epilepsy

BACKGROUND

Although antiseizure medications play a crucial role in the management of epilepsy, their benefit can be compromised due to drug-related problems. Drug therapy problems can lead to poor seizure control, reduced quality of life, and increased morbidity and mortality in patients with epilepsy. However, in our setting, there is limited knowledge about drug therapy problems and the factors that contribute to them.

OBJECTIVE

The aim of this study was to investigate the prevalence and contributing factors of drug-therapy problems among patients with epilepsy.

METHODOLOGY

A hospital-based prospective observational study was conducted at the neurologic clinic of Ayder Comprehensive Specialized Hospital, located in the Tigray region of Northern Ethiopia. The study included adult patients diagnosed with epilepsy who had been taking at least one antiseizure medication for a minimum of six months. Data were collected by conducting patient interviews and expert reviews of medical and medication records. Prior to data review and interviews, each patient provided written informed consent. Drug therapy problems were identified and classified using Cipolle's method, followed by a consensus review conducted with a panel of experts. Statistical analysis was performed using a statistical software package; SPSS version 22. Binary logistic regression analysis was conducted to determine the contributing factors of drug therapy problems. Statistical significance was determined at p<0.05.

RESULTS

A study conducted on 250 participants revealed that 55.2% of the patients experienced one or more drug therapy problems. Our analysis identified a total of 282 drug therapy problems, with a mean of 2±0.52 drug therapy problems per patient. The most commonly observed drug therapy problems were dosage too low (30.0%), noncompliance (22%), adverse drug reaction (18%), and unnecessary drug therapy (16.4%). The commonly involved antiseizure medications in these drug therapy problems were phenytoin (22.8%), Valproic acid (20.8%), and Phenobarbital (18.4%). Furthermore, our findings revealed that combination therapy (AOR: 3.92, 95%CI: 1.19-12.97) and uncontrolled seizure (AOR: 108.37, 95%CI: 38.7-303.6) exhibited significant associations with drug therapy problems.

CONCLUSION

Drug therapy problems were prevalent among patients with epilepsy. The use of combination therapy and the presence of uncontrolled seizures were identified as significant indicators of drug therapy problems. Therefore, more emphasis should be given to patients with multiple medications and uncontrolled seizures.

Idiopathic Epilepsy Risk Allele Trends in Belgian Tervuren: A Longitudinal Genetic Analysis

Idiopathic epilepsy (IE) has been known to be inherited in the Belgian Tervuren for many decades. Risk genotypes for IE in this breed have recently been identified on Canis familiaris chromosomes (CFA) 14 and 37. In the current study, the allele frequencies of these loci were analyzed to determine whether dog breeders had employed a purposeful selection against IE, leading to a reduction in risk-associated allele frequency within the breed over time. The allele frequencies of two generational groupings of Belgian Tervuren with and without IE were compared. Allele frequencies for risk-associated alleles on CFA14 were unchanged between 1985 and 2015, whereas those on CFA37 increased during that time in the control population (p < 0.05). In contrast, dogs with IE showed a decrease (p < 0.05) in the IE risk-associated allele frequency at the CFA37 locus. Seizure prevalence in the Belgian Tervuren appears to be increasing. These results suggest that, despite awareness that IE is inherited, selection against IE has not been successful.

Climate change: Attitudes and concerns of, and learnings from, people with neurological conditions, carers, and health care professionals

OBJECTIVE

Concern about climate change among the general public is acknowledged by surveys. The health care sector must play its part in reducing greenhouse gas emissions and adapting to a changing climate, which will require the support of its stakeholders including those with epilepsy, who may be especially vulnerable. It is important to understand this community's attitudes and concerns about climate change and societal responses.

METHODS

A survey was made available to more than 100 000 people among a section of the neurological community (patients, carers, and clinicians), focused on epilepsy. We applied quantitative analysis of Likert scale responses supported by qualitative analyses of free-text questions with crossover analyses to identify consonance and dissonance between the two approaches.

RESULTS

A small proportion of potential respondents completed the survey; of 126 respondents, 52 had epilepsy and 56 explicitly declared no illness. The survey indicated concern about the impact of climate change on health within this neurological community focused on epilepsy. More than half of respondents considered climate change to have been bad for their health, rising to 68% in a subgroup with a neurological condition; over 80% expected climate change to harm their health in future. Most (>75%) believed that action to reduce greenhouse gas emissions will lead to improved health and well-being. The crossover analysis identified cost and accessibility as significant barriers.

SIGNIFICANCE

The high level of concern about climate change impacts and positive attitudes toward policies to reduce greenhouse gas emissions provide support for climate action from the epilepsy community. However, if policies are implemented without considering the needs of patients, they risk being exclusionary, worsening inequalities, and further threatening neurological health and well-being.

Heat impacts on human health in the Western Pacific Region: an umbrella review

Background

High temperatures and heatwaves are occurring more frequently and lasting longer because of climate change. A synthesis of existing evidence of heat-related health impacts in the Western Pacific Region (WPR) is lacking. This review addresses this gap.

Methods

The Scopus and PubMed databases were searched for reviews about heat impacts on mortality, cardiovascular morbidity, respiratory morbidity, dehydration and heat stroke, adverse birth outcomes, and sleep disturbance. The last search was conducted in February 2023 and only publications written in English were included. Primary studies and reviews that did not include specific WPR data were excluded. Data were extracted from 29 reviews.

Findings

There is strong evidence of heat-related mortality in the WPR, with the evidence concentrating on high-income countries and China. Associations between heat and cardiovascular or respiratory morbidity are not robust. There is evidence of heat-related dehydration and stroke, and preterm and still births in high-income countries in the WPR. Some evidence of sleep disturbance from heat is found for Australia, Japan and China.

Interpretation

Mortality is by far the most studied and robust health outcome of heat. Future research should focus on morbidity, and lower income countries in continental Asia and Pacific Island States, where there is little review-level evidence.

Funding

Funded by the World Health Organization WPR Office.

Health equity integrated epilepsy care and research: A narrative review

BACKGROUND

With the unanimous approval of the Intersectoral Global Action Plan on epilepsy and other neurological disorders by the World Health Organization in May 2022, there are strong imperatives to work towards equitable neurological care.

AIMS

Using epilepsy as an entry point to other neurologic conditions, we discuss disparities faced by marginalized groups including racial/ethnic minorities, Americans living in rural communities, and Americans with low socioeconomic status.

MATERIALS AND METHODS

The National Institute on Minority Health Disparities Research Framework (NIMHD) was used to conduct a narrative review through a health equity lens to create an adapted framework for epilepsy and propose approaches to working towards equitable epilepsy and neurological care.

RESULTS

In this narrative review, we identified priority populations (racial and ethnic minority, rural-residing, and low socioeconomic status persons with epilepsy) and outcomes (likelihood to see a neurologist, be prescribed antiseizure medications, undergo epilepsy surgery, and be hospitalized) to explore disparities in epilepsy and guide our focused literature search using PubMed. In an adapted NIMHD framework, we examined individual, interpersonal, community, and societal level contributors to health disparities across five domains: (1) behavioral, (2) physical/built environment, (3) sociocultural, (4) environment, and (5) healthcare system. We take a health equity approach to propose initiatives that target modifiable factors that impact disparities and advocate for sustainable change for priority populations.

DISCUSSION

To improve equity, healthcare providers and relevant societal stakeholders can advocate for improved care coordination, referrals for epilepsy surgery, access to care, health informatics interventions, and education (i.e., to providers, patients, and communities). More broadly, stakeholders can advocate for reforms in medical education, and in the American health insurance landscape.

CONCLUSIONS

Equitable healthcare should be a priority in neurological care.

COVID-19 in Children with West Syndrome: An Ambispective Study

OBJECTIVES

To study the course of West syndrome (WS) and coronavirus disease-19 (COVID-19) in children with WS who contracted SARS-CoV-2 infection.

METHODS

This ambispective study was conducted at a tertiary-care center in North India between December 2020 and August 2021 after approval from the Institute Ethics Committee. Five children with WS, positive for COVID-19 based on RT-PCR, fulfilled the inclusion criteria.

RESULTS

One child with COVID-19 during the first wave was retrospectively included while four children (of the 70 children screened) were prospectively enrolled. The median age at onset of epileptic spasms was 7 mo (2 boys), and that at presentation with COVID-19 was 18.5 mo. Three had underlying acquired structural etiology. Three were in remission following standard therapy, while two had ongoing spasms at the time of COVID-19 illness. During the illness, two of those in remission continued to be in remission while one child had a relapse. The children with ongoing epileptic spasms had variable course [one had persistent spasms and other had transient cessation lasting 3 wk from day 2 of COVID-19 illness, but electroencephalography (on day 8 of COVID-19 illness) continued to show hypsarrhythmia]. Fever was the most typical symptom (and sometimes the only symptom) of COVID-19, with a duration ranging from 1-8 d. Two children had moderate COVID-19 illness requiring hospitalization, while the rest had a mild illness. All the affected children had complete recovery from COVID-19.

CONCLUSION

The severity of COVID-19 illness in children with WS is often mild, while the subsequent course of WS is variable.

Nanowired Delivery of Cerebrolysin with Mesenchymal Stem Cells Attenuates Heat Stress-Induced Exacerbation of Neuropathology Following Brain Blast Injury

Blast brain injury (bBI) following explosive detonations in warfare is one of the prominent causes of multidimensional insults to the central nervous and other vital organs injury. Several military personnel suffered from bBI during the Middle East conflict at hot environment. The bBI largely occurs due to pressure waves, generation of heat together with release of shrapnel and gun powders explosion with penetrating and/or impact head trauma causing multiple brain damage. As a result, bBI-induced secondary injury causes breakdown of the blood-brain barrier (BBB) and edema formation that further results in neuronal, glial and axonal injuries. Previously, we reported endocrine imbalance and influence of diabetes on bBI-induced brain pathology that was significantly attenuated by nanowired delivery of cerebrolysin in model experiments. Cerebrolysin is a balanced composition of several neurotrophic factors, and active peptide fragment is capable of neuroprotection in several neurological insults. Exposure to heat stress alone causes BBB damage, edema formation and brain pathology. Thus, it is quite likely that hot environment further exacerbates the consequences of bBI. Thus, novel therapeutic strategies using nanodelivery of stem cell and cerebrolysin may further enhance superior neuroprotection in bBI at hot environment. Our observations are the first to show that combined nanowired delivery of mesenchymal stem cells (MSCs) and cerebrolysin significantly attenuated exacerbation of bBI in hot environment and induced superior neuroprotection, not reported earlier. The possible mechanisms of neuroprotection with MSCs and cerebrolysin in bBI are discussed in the light of current literature.

Neurodegenerative Diseases: Implications of Environmental and Climatic Influences on Neurotransmitters and Neuronal Hormones Activities

Neurodegenerative and neuronal-related diseases are major public health concerns. Human vulnerability to neurodegenerative diseases (NDDs) increases with age. Neuronal hormones and neurotransmitters are major determinant factors regulating brain structure and functions. The implications of environmental and climatic changes emerged recently as influence factors on numerous diseases. However, the complex interaction of neurotransmitters and neuronal hormones and their depletion under environmental and climatic influences on NDDs are not well established in the literature. In this review, we aim to explore the connection between the environmental and climatic factors to NDDs and to highlight the available and potential therapeutic interventions that could use to improve the quality of life and reduce susceptibility to NDDs.

Circannual incidence of seizure evacuations from the Canadian Arctic

OBJECTIVES

Emerging evidence suggests that circadian rhythms affect seizure propensity in addition to, and possibly independent of, sleep-wake states. Subject to extreme seasonal changes in light and dark, the northerly Arctic can serve as a "natural experiment" to assess the real-life impact of environmental influences on seizure severity. Therefore, we evaluated the timing of seizure evacuations over 11.25 years in a well-defined region of the Canadian Arctic.

METHODS

Retrospective review of EEG database and patient records at the single "bottleneck" hospital to which all patients from the Kivalliq Region in Nunavut, Canada are evacuated for seizure emergencies. We calculated the mean resultant length (MRL) of circular data for circannual analysis, and conducted Rayleigh's test to assess for a statistical departure from circular uniformity.

RESULTS

Screening 40,392 EEGs, we found 117 medical evacuations from 99 distinct individuals from September 2009 to November 2020. Most evacuations occurred month-wise in May (19%); week-wise within a 7-day period in February (5%), June (5%), or November (5%); and day-wise within a 24-hour period in June (3%) or November (3%). Maximal MRL clustering occurred in April no matter if analyzed by day (0.16333, p = 0.04), week (0.16296, p = 0.04), or month (0.1736, p = 0.03).

CONCLUSIONS

A relative circannual increase in seizure evacuations between the winter and summer solstices may be related to increasing sleep loss when day length grows. Fewer evacuations between the summer and winter solstices may be related to decreased daylight and "catching up" on sleep when night length grows. Additional factors likely also play a role in circannual variation of seizure evacuations in the Arctic, which warrants further research.

Weather patterns and occurrence of epileptic seizures

Background

The results of various studies that have so far evaluated the influence of meteorological conditions on seizures are often divergent. No studies have been performed so far that evaluate the possible correlation between the occurrence of seizure-related events, surface and upper level atmospheric conditions and biometeorological forecasts. The aim of this study is to investigate those interactions.

Methods

Records of “Sveti Duh” University hospital, Zagreb, Croatia between January 2016 and May 2020 were analysed in order to determine number of patients per day who were assessed through Emergency room because of a recent epileptic seizure. The dates were assessed for surface and upper level atmospheric conditions and biometeorological forecasts. Analyses of these factors were performed for two consecutive days preceding that day, the day of seizure, as well as for the following day. Data was analysed using chi-squared test, Mann-Whitney U-test or Kruskal-Wallis test (with Conover’s test for post-hoc analyses), depending on variable type. Additionaly, logistic regression was used to study effects of variables on seizure occurrence. Statistical significance was set to p < 0.05.

Results

Results showed significant difference between the numbers of patients with seizure depending on upper level type on the following day. We also observed fewer daily patients with seizures when the synoptic situation on the following day was high pressure field then when it was low pressure or non-gradient pressure field (observed just during the colder part of the year), which was supported in our regression analyses. A greater frequency of seizures was observed if the biometerological prognosis was deemed unfavourable on the following day. Furthermore, our results showed significantly larger proportion of days with seizure patients in warmer, than in colder days of the year.

Conclusions

All of the analyzed weather-related parameters seem to be associated with daily numbers of seizures on the previous day. The reason behind this phenomenon is uncertain; however, the results indicate that weather patterns have a certain influence on patients with epilepsy, but are not yet fully understood or adequately appreciated.

Multivariate analysis of the impact of weather and air pollution on emergency department visits for unprovoked seizure among children: A retrospective clinical observational study

BACKGROUND

An unprovoked seizure is a seizure or a cluster of seizures occurring within 24 h in a patient older than 1 month of age without precipitating factors. Recent studies have reported that extrinsic factors, such as meteorological conditions and air pollutants, may be important in seizure occurrence. Thus, this study aimed to examine the association between the number of visits to the emergency department (ED) by children for nighttime unprovoked seizures and exposure to multi-faceted factors, such as meteorological conditions and air pollution.

METHODS

We conducted a clinical observational analysis and reviewed consecutive patients younger than 16 years of age who visited the primary ED center in Kobe City, Japan, during nighttime (7:30 p.m.-7:00 a.m.) between January 1, 2011 and December 31, 2015. We investigated the effects of meteorological factors and air pollutants on the number of patients with unprovoked seizures using multivariate analysis of Poisson regression estimates.

RESULTS

In total, 151,119 children visited the ED, out of which 97 patients presented with unprovoked seizures. The mean age of the patients was 4.7 years (range, 1 month to 15.3 years), and 54.6% of them were boys. The total number of patients with unprovoked seizures showed no significant changes with the seasons; however, there were dominant peaks during the fall and fewer visits during the summer. The multivariate analysis of Poisson regression estimates revealed a significant positive relationship between the number of patients presenting with unprovoked seizures and precipitation (+1 patient/87 mm; p = 0.03) and methane (+1 patient/0.14 ppm; p = 0.03) levels and a negative relationship between the number of patients presenting with unprovoked seizures and nitrogen dioxide level (-1 patient/0.02 ppm; p = 0.04).

CONCLUSIONS

The present study is the first to evaluate the association between the number of children who presented to the ED with nighttime unprovoked seizures and environmental factors after controlling for confounding factors.

Climate change and neurodegenerative diseases

The climate change induced global warming, and in particular the increased frequency and intensity of heat waves, have been linked to health problems. Among them, scientific works have been reporting an increased incidence of neurological diseases, encompassing also neurodegenerative ones, such as Dementia of Alzheimer's type, Parkinson's Disease, and Motor Neuron Diseases. Although the increase in prevalence of neurodegenerative diseases is well documented by literature reports, the link between global warming and the enhanced prevalence of such diseases remains elusive. This is the main theme of our work, which aims to examine the connection between high temperature exposure and neurodegenerative diseases. Firstly, we evaluate the influence of high temperatures exposure on the pathophysiology of these disorders. Secondly, we discuss its effects on the thermoregulation, already compromised in affected patients, and its interference with processes of excitotoxicity, oxidative stress and neuroinflammation, all of them related with neurodegeneration. Finally, we investigate chronic versus acute stressors on body warming, and put forward a possible interpretation of the beneficial or detrimental effects on the brain, which is responsible for the incidence or progression of neurological disorders.