Febrile seizures: Are they truly benign? Longitudinal analysis of risk factors and future risk of afebrile epileptic seizure based on the national sample cohort in South Korea, 2002–2013

Clinical Profile and Predictors of Recurrent Simple Febrile Seizure

BACKGROUND

Recurrent simple febrile seizure (SFS) refers to febrile seizure (FS) that recurs within 24 hours. Patients with recurrent SFS often undergo unnecessary neurodiagnostic tests. To address this, we compared the clinical characteristics of recurrent SFS with those of SFS and investigated the risk factors associated with recurrent SFS.

METHODS

We retrospectively reviewed electronic medical records of patients aged six to 60 months who had been hospitalized for FS at two training hospitals between January 2016 and December 2019. The primary outcome was a comparison of the clinical features of patients with SFS and recurrent SFS. Additionally, the risk factors associated with seizure recurrence within 24 hours were evaluated.

RESULTS

Three quarters (n = 191, 75.2%) of the 254 enrolled patients experienced a single seizure episode during the febrile illness period. The remaining 63 patients (24.8%) were diagnosed with recurrent SFS. Significant differences between SFS and recurrent SFS were observed in the history of recurrent SFS, time from fever onset to seizure, and body temperature on hospital arrival. Multiple logistic regression analysis revealed that a history of previous recurrent SFS (odds ratio [OR] 10.161) and a body temperature below 39°C on arrival (OR 2.377) were significantly associated with early seizure recurrence.

CONCLUSIONS

This study highlights that early FS recurrence is common and has a self-limiting clinical course similar to that of SFS. We recommend close monitoring of the patient for six to eight hours when a history of early recurrence is present or if the seizure occurs at a low body temperature.

Higher Risk of Psychiatric Disorders in Children With Febrile Seizures: A Nationwide Cohort Study in Taiwan

BACKGROUND

Febrile seizures occur commonly in children aged between six months and six years. A previous Danish study found a positive correlation between febrile seizures and the overall incidence of psychiatric disorders. This population-based nationwide observational study was conducted to investigate the association between febrile seizures and different psychiatric disorders in Taiwan and the associated risk factors.

METHODS

This cohort study used data from the National Health Insurance Research Database in Taiwan-a nationwide claims database covering >99% of the Taiwanese population. The study period was from January 2000 to December 2015; the overall median follow-up time was 11.04 ± 10.95 years. Overall, 2464 children with febrile seizures diagnosed between 2000 and 2015 met the inclusion criteria, and 7392 children without febrile seizures matched by index year, age, and sex were included in the control cohorts. Febrile seizures and psychiatric disorders were measured as the exposure and main outcomes, respectively.

RESULTS

Children with febrile seizures (n = 2463) were at a high risk of psychiatric disorders (adjusted hazard ratio, 4.70; 95% confidence interval [CI], 2.44 to 7.30; P < 0.001). The risk for anxiety was the highest (adjusted hazard ratio, 21.92; 95% CI, 11.40 to 34.05; P < 0.001).

CONCLUSIONS

When treating children with febrile seizures, particular attention should be paid to the symptoms of psychiatric disorders, as early referral may be beneficial for these children.

Hypertensive disorders of pregnancy increase the incidence of febrile seizures in offspring

BACKGROUND

Intrauterine exposure to hypertensive disorders of pregnancy (HDP) may increase the risk of neuropsychiatric disorders. This investigation examined for associations between maternal HDP and febrile seizures (FS) in offspring by the age of three years.

METHODS

The present cohort study analyzed data from the Japan Environment and Children's Study, a large national birth cohort. We included mother-child pairs recruited between January 2011 and March 2014. Information regarding maternal HDP, the presence of FS in offspring up to 3 years of age, and potential confounding factors were assessed using written questionnaires administered to mothers.

RESULTS

A total of 77,699 mother-child dyads were analyzed. The prevalence of FS was 8.4% in children without HDP exposure, 10.6% in those exposed to mild HDP, and 10.4% in those with severe HDP exposure. Among children with full-term birth, logistic regression analysis indicated that exposure to mild or severe HDP was significantly associated with a higher incidence of FS (adjusted odds ratio [95% confidence interval]: 1.27 [1.05-1.53] and 1.27 [0.90-1.78], respectively, P for trend = 0.008), compared with children without HDP exposure.

CONCLUSION

In children with full-term birth, intrauterine exposure to HDP was significantly associated with FS by the age of three years.

IMPACT

This study revealed a significant association between intrauterine exposure to hypertensive disorders of pregnancy (HDP) and the subsequent development of febrile seizures (FS) in offspring by three years. This increased incidence of FS by HDP was independent of preterm birth status. This is the first large nationwide birth cohort study showing the impact of intrauterine exposure to HDP on FS in early childhood.

Febrile Seizures: An Updated Narrative Review for Pediatric Ambulatory Care Providers

BACKGROUND

While generally self-limited, febrile seizures result in significant familial distress. Ambulatory pediatric care providers must be prepared to counsel families on the causes, risk factors, management principles, and prognosis of children with febrile seizures.

OBJECTIVE

To provide an updated, evidence-based review of febrile seizures focused on the needs of an ambulatory pediatric care provider.

METHODS

A narrative review of the literature prioritizing landmark articles, metanalyses, longitudinal population longitudinal cohort studies and national level guidelines.

RESULTS

Febrile seizures are aberrant physiological responses to fever in children caused by complex interactions of cytokine mediated neuroinflammation, environmental triggers, and genetic predisposition. Other than investigations to determine fever etiology, routine bloodwork, lumbar punctures, neuroimaging and electroencephalograms are low yield. The general prognosis is excellent, however, clinicians should be aware of long-term outcomes including: cognitive impairment with non-simple febrile seizures; neuropsychiatric associations; recurrent febrile seizure and epilepsy risk factors; and the association between complex febrile seizures and sudden unexpected death. Children with a high risk of recurrence, complex febrile seizures, limited access to care, or extreme parental anxiety may benefit from intermittent oral diazepam prophylaxis.

CONCLUSION

Clinicians should consider four management priorities: 1) terminating the seizure; 2) excluding critical differential diagnoses; 3) investigating fever etiology; and 4) providing adequate counselling to families. The clinical approach and prognosis of febrile seizure can be based on subtype. Children with non-simple (i.e. complex or febrile status epilepticus) febrile seizures require closer care than the vast majority of children with simple febrile seizures, who have excellent outcomes.

Effects of the coronavirus disease outbreak on the development of neurological disorders in children: A comparison of the incidence of febrile seizure and epilepsy using an interrupted time-series approach

BACKGROUND

With the outbreak of COVID-19, school closures and quarantines following social distancing have brought significant changes to children's lifestyles. Therefore, we aimed to compare the population-adjusted incidence of febrile seizures(FS) and epilepsy before and after the COVID-19 outbreak in Korea and to assess the effects of the COVID-19 outbreak on the incidence by region and age group.

METHODS

A retrospective cohort study was conducted using nationwide claims data and covid data from January 2019 to December 2020. The incidence of diseases and difference in incidence before (Jan 20 to Dec 30, 2019) and after (Jan 20 to Dec 30, 2020) the COVID-19 outbreak was measured using rate ratio. An Interrupted time series analysis was used to identify the effect of COVID-19 on trends of FS and epilepsy. Subgroup analysis by age, sex, insurance, and risk of coronavirus by area were conducted.

RESULTS

Following the onset of the pandemic, the number of newly diagnosed FS cases decreased sharply by 69 % (24,182 to 7238), whereas the incidence of epilepsy, increased to 1.02 times (30,286-29,312), when adjusted in proportion to the population. Notably, a greater decrease in the incidence of FS were found in the regions with high-risk of coronavirus. A result of segmented regression analysis proved the decrease was significant and made immediately after the pandemic started(p < 0.001). In contrast to the incidence of FS, that of epilepsy did not exhibit a significant month-to-month change during the baseline period, immediately after the pandemic started, and during the pandemic.

CONCLUSIONS

The COVID-19 outbreak and resulting social distancing measures reduced the incidence of febrile seizure immediately rather than gradually. Unlike in the case of acute febrile seizure, the COVID-19 pandemic had no effect on the incidence of chronic epilepsy.

Development of a prediction nomogram model of recurrent febrile seizures in pediatric children

The purpose of this study is to develop a prediction nomogram of recurrent febrile seizures in pediatric children based on the identified predictors for developing recurrent febrile seizures. This is a retrospective observational study. The medical records of 320 febrile seizure-afflicted children admitted to Zhoushan Women and Children Hospital from March 2019 to January 2023 were retrospectively reviewed. Children were divided into the recurrent febrile seizures group and the non-recurrent febrile seizures group. The predictors of recurrent febrile seizures were identified by univariate and multivariate analyses. A prediction nomogram model was developed via R software. The performance of the nomogram was internally validated to assess the model's discrimination and consistency, and decision curve analysis was employed to assess clinical utility. There were 41 out of 320 cases that had recurrent febrile seizures during the observation period, with a 12.81% prevalence rate of recurrent febrile seizures. The predictors of recurrent febrile seizures were young age at the first febrile seizures, a family history of febrile seizures in a first-degree relative, diurnal variation of initial febrile seizures occurrence, gender, and a low level of C-reactive protein. The area under the receiver operating characteristic curve of the nomogram is 0.795 (95% confidence interval: 0.720-0.871). Calibration plots and the result of the Hosmer-Lemeshow test (P = 0.472) reveal satisfactory consistency. Decision curve analysis showed a significant net benefit of the nomogram.

CONCLUSIONS

The prediction nomogram model demonstrates good performance and clinical utility, which would be a convenient tool for the detection of children in pediatrics with high-risk recurrent febrile seizures. It is useful for pediatric medical staff to provide early medical interventions and family counseling.

WHAT IS KNOWN

• A proportion of children experience recurrences of febrile seizures. • Recognition of risk factors for recurrent FS in pediatrics would be useful for the prediction of risk probabilities and help provide tailored counseling and follow-up.

WHAT IS NEW

• A nomogram model is developed for risk prediction of recurrent febrile seizures in this study, which would be a convenient risk prediction tool in pediatrics. • The predictor of diurnal variation of recurrent febrile seizures is with new ideas.

Depressive, Anxiety, and Stress Symptoms in Parents of Children Being Admitted for Febrile Seizures in a Tertiary Hospital in the East Coast of Malaysia

Febrile seizures in children are an alarming experience for parents. This study aimed to assess the psychological functioning of parents of children when they were being admitted for treatment of febrile seizures in the hospital, the importance of which is clear, since parents are the primary custodian of their children. This is a cross-sectional study conducted on 110 participants whose child had been admitted for a febrile seizure to Hospital Universiti Sains Malaysia from September 2020 until June 2021. The depression, anxiety, and stress levels were determined based on a validated Bahasa Melayu questionnaire of the Depression Anxiety Stress Scale (DASS-21). In addition, multiple logistic regression was used to determine the associated factors related to the participants' psychological functioning. The mean age of children with febrile seizures were 21 months old, and most children showed features of simple febrile seizures (71.8%). The prevalence of anxiety, stress, and depression were 58.2%, 29%, and 23.6%, respectively. Using multiple logistic regression, child age, family history of febrile seizures, family history of epilepsy, and length of stay in the ward were found to be significantly associated with anxiety when adjusted for other variables. Otherwise, for depression and stress, no significant associated variables were found when adjusted for other variables. Anxiety was highly reported by participants when their children were admitted for febrile seizures. Several factors impacted their anxiety, including the lower the child's age was, participants with no family history of febrile seizures before, and the longer duration of hospital stay. Therefore, further study and intervention on reducing the parent's anxiety could be emphasized in the future.

The Association of Sociodemographic Factors, Postictal Symptoms, and Medical History With Seizure Type in Patients With Epilepsy: A Cross-Sectional Study

Background Approximately 50 million people globally suffer from epilepsy. The prevalence of epilepsy in Saudi Arabia has been reported at 6.5 per 1,000 persons, affecting nearly 1% of the entire population. However, limited data is available in the country regarding the sociodemographic factors affecting epilepsy and its associated postictal symptoms, which may lead to stigmatization and negatively impact patients. Methods A cross-sectional study was conducted at King Abdulaziz University Hospital (KAUH) in a survey format. Ethical approval was obtained from the Research Ethics Committee of the Faculty of Medicine at King Abdulaziz University. The study population included patients with epilepsy who visited King Abdulaziz University Hospital's outpatient neurology clinics from October 2021 to March 2022. Results The study participants' average age at the time of the first seizure was 16.5 years, with patients experiencing seizures as early as within the first year of life and as late as 70 years of age. Patients who had had their first seizure during the first year of life did not have any schooling (p<0.0001) and had learning difficulties (p<0.00001). Focal onset impaired awareness seizures were significantly associated with motor weakness (p=0.023) and mood alterations (p=0.014), while postictal fear, anxiety or panic, and sleep disruption were statistically significant for focal onset aware seizures (p=0.015 and p=0.050). Conclusion This study highlights the sociodemographic differences between patients in Saudi Arabia and in other areas. It may also point to novel findings regarding the postictal symptoms associated with the various seizure types.

Seasonal Trend of Viral Prevalence and Incidence of Febrile Convulsion: A Korea Public Health Data Analysis

Febrile convulsion (FC) is the most common seizure disease in children, which occurs with a fever. We investigated the Korean Health Insurance Review and Assessment Service data of patients aged between 6 months and 5 years at the time of FC diagnosis. Diseases that can cause seizures with fever, such as neoplasms, metabolic disorders, nervous system disorders, cerebrovascular diseases, perinatal problems, and congenital abnormalities, were excluded. Weekly virus-positive detection rate (PDR) data were obtained from the Korea Disease Control and Prevention Agency for adenovirus, parainfluenza virus, respiratory syncytial virus (HRSV), influenza virus, coronavirus (HCoV), rhinovirus (HRV), bocavirus, metapneumovirus (HMPV), rotavirus, norovirus, and astrovirus. Using the Granger test, we then analyzed the monthly PDR and investigated the association between FC incidence and monthly PDR. We additionally identified monthly and seasonal FC incidence trends using the autoregressive integrated moving average. Between 2015 and 2019, 64,291 patients were diagnosed with FC. Annually, the incidence was the highest in May and the lowest in October. Most patients were diagnosed during the spring (26.7%). The PDRs for HRSV, HCoV, HRV, HMPV, and norovirus were associated with FC incidence after 1 month.

The Negative Association between Breastfeeding Duration and Infant Febrile Seizure: A Retrospective Case-Control Study

Two to five percent of infants and children experience febrile seizures (FS). Breastfeeding is beneficial to the health of mothers and children. Nevertheless, the benefits of breastfeeding in reducing FS remain unclear; thus, the present study aimed to evaluate this association. The case group was selected from 2010 to 2019, and the selected population was children younger than 5 years (i.e., children born from 2005−2019). The control group was selected from newborn infants at our hospital born between 2005 and 2019. Finally, 55 children with FS and 110 children in the control group were recruited. The results show longer breastfeeding duration is associated with an increased risk of FS (adjusted odds ratio: 1.06, 95% confidence interval: 1.01−1.11, p = 0.028). When comparing cases of FS with the control group, the percentage of inclusive breastfeeding over 12 months (32.7% vs. 9.1%, p = 0.017) and longer duration of exclusive breastfeeding were higher (10.86 ± 11.82 vs. 5.40 ± 7.17 months, p < 0.001). However, the comparison of the prevalence of FS between the different breastfeeding duration groups did not reach statistical significance. In conclusion, our study showed that a longer breastfeeding duration was associated with a higher risk of FS. Future large-scale studies evaluating the association between breastfeeding duration and febrile seizures are needed.

Breastfeeding and risk of febrile seizures in the first 3 years of life: The Japan Environment and Children's Study

OBJECTIVE

Our study was conducted to examine the association between breastfeeding and febrile seizures (FS) in the first 3 years of life.

METHODS

We analyzed the dataset of the Japan Environment and Children's Study (JECS), which is a birth cohort study undertaken to elucidate the influence of environmental factors on children's health during the fetal period and early childhood. Information on feeding duration and feeding pattern, as well as information on febrile seizures, were obtained from questionnaires sent to mothers/caregivers. We categorized a child as having experienced FS if the child was reported as having been diagnosed with FS in the first 3 years. Modified Poisson regression with a robust error variance was used to estimate the effect of duration of breastfeeding and the risk of FS.

RESULTS

Of the 84,321 children included in the analysis, 6264 (7.4%) were reported to have experienced FS at least once in the first 3 years of life. Multivariate analyses showed that the risk of FS during the first 3 years of life tended to decrease as the duration of breastfeeding increased. Male sex and frequent fever episodes were also associated with an increased risk of FS.

CONCLUSIONS

Continued breastfeeding until 2 years of age, the most susceptible age for FS, had a small but protective effect on FS.

Incidence and risk factors of acute encephalopathy with biphasic seizures in febrile status epilepticus

OBJECTIVE

To clarify the incidence and risk factors of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) in pediatric patients with febrile status epilepticus (FSE).

METHODS

We retrospectively surveyed patients with FSE (≥20 min and ≥40 min) who were younger than 6 years by mailing a questionnaire to 1123 hospitals in Japan. The survey period was 2 years. We then collected clinical data on patients with prolonged febrile seizures (PFS) ≥40 min and those with AESD, and compared clinical data between the PFS and AESD groups.

RESULTS

The response rate for the primary survey was 42.3%, and 28.0% of hospitals which had applicable cases responded in the secondary survey. The incidence of AESD was 4.3% in patients with FSE ≥20 min and 7.1% in those with FSE ≥40 min. In the second survey, a total of 548 patients had FSE ≥40 min (AESD group, n = 93; PFS group, n = 455). Univariate analysis revealed significant between-group differences in pH, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine kinase, NH₃, procalcitonin (PCT), uric acid, blood urea nitrogen, creatinine (Cr), and lactate. Multivariate analysis using stratified values showed that high PCT was an only risk factor for AESD. A prediction score of ≥3 was indicative of AESD, as determined using the following indexes: HCO3^- < 20 mmol/L (1 point), Cl <100 mEq/L (1 point), Cr ≥0.35 mg/dL (1 point), glucose ≥200 mg/dL (1 point), and PCT ≥1.7 pg/mL (2 points). The scoring system had sensitivity of 84.2% and specificity of 81.0%.

CONCLUSION

Incidence data and prediction scores for AESD will be useful for future intervention trials for AESD.

CELSR3 variants are associated with febrile seizures and epilepsy with antecedent febrile seizures

Aims

To identify novel pathogenic gene of febrile seizures (FS)/epilepsy with antecedent FS (EFS+).

Methods

The trio‐based whole‐exome sequencing was performed in a cohort of 462 cases with FS/EFS+. Silico programs, sequence alignment, and protein modeling were used to predict the damaging of variants. Statistical testing was performed to analyze gene‐based burden of variants.

Results

Five heterozygous missense variants in CELSR3 were detected in five cases (families) with eight individuals (five females, three males) affected. Two variants were de novo, and three were identified in families with more than one individual affected. All the variants were predicted to be damaging in silico tools. Protein modeling showed that the variants resulted in disappearance of multiple hydrogen bonds and one disulfide bond, which potentially caused functional impairments of protein. The frequency of CELSR3 variants identified in this study was significantly higher than that in controls. All affected individuals were diagnosed with FS/EFS+, including six patients with FS and two patients with EFS+. All cases presented favorable outcomes without neurodevelopmental disorders.

Conclusions

CELSR3 variants are potentially associated with FS/EFS+.

The recent characteristics of influenza-related hospitalization in Japanese children

We investigated the recent epidemiology and characteristics of influenza-related hospitalization in Japanese children. This study included 3741 children with influenza. Children hospitalized for febrile seizures (FS) induced by etiologies other than influenza also served as a disease control. Most outpatients (92.8%) visited our hospital with complaints of respiratory symptoms, whereas FS were the most predominant symptoms of inpatients (58/154, 37.7%). Children with influenza-induced FS were significantly older than those with FS induced by other etiologies (P <0.001). Although the characteristics of severe influenza may vary throughout the world, the analysis of influenza-induced neurological disorders is important for understanding its epidemiology.

Seizure prevalence in children aged up to 3 years: a longitudinal population-based cohort study in Japan

OBJECTIVE

To investigate the prevalence of seizures/febrile seizures in children up to 3 years of age and examine the effects of gestational age at birth on the risk for febrile seizures.

DESIGN

Retrospective longitudinal population-based cohort study.

SETTING

Kobe City public health center, Kobe, Japan, from 2010 to 2018.

PARTICIPANTS

Children who underwent a medical check-up at 3 years of age.

METHODS

Information regarding seizures was collected from the parents of 96 014 children. We identified the occurrence of seizure/febrile seizure in 74 017 children, whose gestational ages at birth were noted. We conducted a multivariate analysis with the parameter, gestational age at birth, to analyse the risk of seizure. We also stratified the samples by sex and birth weight (<2500 g or not) and compared the prevalence of seizure between those with the term and late preterm births.

RESULTS

The prevalence of seizure was 12.1% (11.8%-12.3%), 13.2% (12.2%-14.4%), 14.6% (12.4%-17.7%) and 15.7% (10.5%-22.8%) in children born at 37-41, 34-36, 28-33 and 22-27 gestational weeks, respectively. The prevalence of febrile seizures was 9.0% (8.8%-9.2%), 10.5% (9.5%-11.5%), 11.8% (9.7%-14.5%) and 11.2% (6.9%-17.7%) in children born at 37-41, 34-36, 28-33 and 22-27 gestational weeks, respectively. Male was an independent risk factor for seizures (OR: 1.15, 95% CI 1.09 to 1.20; absolute risk increase 0.014, 95% CI 0.010 to 0.019) and febrile seizures (OR: 1.21, 95% CI 1.15 to 1.28; absolute risk increase 0.016, 95% CI 0.012 to 0.020), respectively. Late preterm birth was not associated with an increased risk of seizure/febrile seizure.

CONCLUSIONS

Although very preterm birth may increase the risk of seizure/febrile seizure, the risk associated with late preterm birth is considerably small and less than that associated with male.

Neurogenic pulmonary edema following febrile status epilepticus in a 22-month-old infant with multiple respiratory virus co-detection: a case report

BACKGROUND

Neurogenic pulmonary edema is a rare but serious complication of febrile status epilepticus in children. Comprehensive screening for viral pathogens is seldomly performed in the work-up of febrile children.

CASE PRESENTATION

A 22-month-old girl presented with her first episode of febrile status epilepticus, after which she developed acute pulmonary edema and respiratory failure. After the termination of seizure activity, the patient was intubated and managed on mechanical ventilation in the emergency room. The resolution of respiratory failure, as well as the neurological recovery, was achieved 9 h after admission, and the patient was discharged 6 days after admission without any complications. Molecular biological diagnostic methods identified the presence of human coronavirus HKU1, influenza C virus, and human parainfluenza virus 2 from the patient's nasopharyngeal specimens.

CONCLUSIONS

Neurogenic pulmonary edema following febrile status epilepticus was suspected to be the etiology of our patient's acute pulmonary edema and respiratory failure. Timely seizure termination and rapid airway and respiratory intervention resulted in favorable outcomes of the patient. Molecular biological diagnostic methods identified three respiratory viruses; however, their relevance and association with clinical symptoms remain speculative.