Epilepsy and deprivation, a data linkage study

Epilepsies with onset during the first year of life: A prospective study on syndromes, etiologies, and outcomes

OBJECTIVE

Infantile seizures cause great concern for both doctors and parents. In addition to modern neuroimaging and genetics, clinical tools helpful in predicting the course of the disease are needed. We prospectively studied the incidence, electroclinical characteristics and etiologies of epilepsy syndromes with onset before the age of 12 months and looked for prognostic determinants of outcome by age 24 months.

METHODS

From February 2017 through May 2019, we recruited all eligible infants diagnosed with epilepsy at our unit. Data on electroclinical studies, genetic investigations and drug response were gathered prospectively. The infants were given a structured neurological examination (Hammersmith Infantile Neurological examination [HINE] and Griffiths scales) at predetermined intervals until age 24 months at which age neurocognitive evaluation with Bayley scales was performed.

RESULTS

Included were 60 infants (27 female). The mean onset age of epilepsy was 5.3 (±2.5 standard deviation) months. The incidence of epilepsy in the population-based cohort was 131 (95% confidence interval 99-172)/100 000. Epilepsy syndrome was identified in 80% and etiology in 58% of infants. Self-limited infantile epilepsy was the second most common syndrome (incidence 18/100 000) after infantile epileptic spasms syndrome. PRRT2 was the most common monogenic cause. At age 24 months, 37% of the infants had drug-resistant epilepsy (DRE) and half had a global developmental delay (GDD). Abnormal first HINE was the strongest predictor of GDD, followed by DRE and identified etiology. DRE was associated with structural etiology and GDD. Those with normal first HINE and good response to treatment had favorable outcomes, irrespective of the identified etiology.

SIGNIFICANCE

Our results support a high incidence of self-limited epilepsy in infancy and PRRT2 as the genetic cause in the first year of life. Notwithstanding the advances in etiological discovery, we want to highlight the importance of clinical evaluation as standardized neurological examination with HINE proved a valuable tool in prognostication.

PLAIN LANGUAGE SUMMARY

One in every 700-800 babies develop epilepsy within the first year after birth. Our study identified an epilepsy syndrome in 80% and the cause of epilepsy in 60% of the participants. By age 2 years, over one-third of the children still experienced seizures, and almost half faced significant developmental delay. Structural brain abnormalities increased the likelihood of difficult epilepsy and developmental challenges. Babies whose epilepsy was caused by a gene defect varied widely in development and response to medications. Babies with normal neurological examination at first visit, especially if their seizures stopped quickly, had favorable development.

Socioeconomic status in adulthood of children with and without a history of seizures: A retrospective cohort study

OBJECTIVE

Compare adulthood socioeconomic status for children with and without a history of seizures.

METHODS

Retrospective cohort study using Aberdeen Children of the Nineteen Fifties (ACONF) data comprising children born 1950-1956 attending primary school 1962-1964, with follow-up data collected in 2001. Adulthood socioeconomic status was based on registrar general measure of occupational social class and categorised as high or low. We adjusted for potentially confounding variables including childhood socioeconomic status, behavioural issues (Rutter A/B scores), biological sex, school test scores, educational attainment, parental engagement with education, peer-status in school, and alcohol use in adulthood. A multivariate binary logistic regression was performed to estimate the adjusted association between children with a history of seizures of any type (for example febrile seizures, or provoked seizures of any other etiology or seizures in the context of epilepsy) or severity and adult socioeconomic status. Multiple imputation using the Monte-Carlo-Markov-Chain method accounted for missing data.

RESULTS

Pooled estimates (N = 2,208) comparing children with a history of seizures (n = 81) and children without a history of seizures (n = 2,127) found no differences between these cohorts in terms of adulthood socioeconomic status in both unadjusted (Odds Ratio (OR) 1.45 [95 % CI 0.71-2.96], p = 0.31) and adjusted (1.02 [0.46, 2.24], p = 0.96) analyses. Compared to males, females were at increased odds of having a lower socioeconomic status in adulthood (1.56 [1.13-2.17], p = 0.01).Compared to those with low educational attainment, those with moderate (0.32 [0.21, 0.48], p < 0.001) and high (0.12 [0.07, 0.20], p < 0.001) educational attainment were at reduced odds of having a lower socioeconomic status in adulthood.

CONCLUSION

Cognitive problems in childhood (using educational attainment and scores on primary school tests proxy markers for cognition) rather than a history of seizures per se, were associated with lower SES in a population of adults born 1950-56 in Aberdeen. This relationship may be different depending on the time in history and nation/region of study. Given the changes in health, education and social support in the management of children with seizures over time, it would be of interest to investigate outcomes in a contemporary cohort. Such studies should ideally have validated diagnoses of seizures, details on seizure characteristics such as seizure type and severity, and a large sample size using national data.

On the Dependence of the Critical Success Index (CSI) on Prevalence

The critical success index (CSI) is an established metric used in meteorology to verify the accuracy of weather forecasts. It is defined as the ratio of hits to the sum of hits, false alarms, and misses. Translationally, CSI has gained popularity as a unitary outcome measure in various clinical situations where large numbers of true negatives may influence the interpretation of other, more traditional, outcome measures, such as specificity (Spec) and negative predictive value (NPV), or when unified interpretation of positive predictive value (PPV) and sensitivity (Sens) is needed. The derivation of CSI from measures including PPV has prompted questions as to whether and how CSI values may vary with disease prevalence (P), just as PPV estimates are dependent on P, and hence whether CSI values are generalizable between studies with differing prevalences. As no detailed study of the relation of CSI to prevalence has been undertaken hitherto, the dataset of a previously published test accuracy study of a cognitive screening instrument was interrogated to address this question. Three different methods were used to examine the change in CSI across a range of prevalences, using both the Bayes formula and equations directly relating CSI to Sens, PPV, P, and the test threshold (Q). These approaches showed that, as expected, CSI does vary with prevalence, but the dependence differs according to the method of calculation that is adopted. Bayesian rescaling of both Sens and PPV generates a concave curve, suggesting that CSI will be maximal at a particular prevalence, which may vary according to the particular dataset.

Prevalence, demographic and spatial distribution of treated epilepsy in France in 2020: a study based on the French national health data system

BACKGROUND

Although still incomplete, the epidemiology of epilepsy shows substantial variations in the burden of the condition according to demographic, social and territorial characteristics. This study aimed to estimate the prevalence of treated epilepsy and to investigate its demographic and spatial distribution in 2020 in France, a country where the nationwide epidemiological situation of the condition remains largely unknown.

METHODS

We used the French national health data system, which covers nearly the entire population residing in France (over 67 million of inhabitants in metropolitan and overseas departments). Prevalent cases were identified using long-term disease status, hospitalisation for epilepsy (ICD-10 codes G40 or G41), and reimbursements for antiseizure medications and electroencephalograms.

RESULTS

In 2020, we identified 685,122 epilepsy cases, corresponding to an overall prevalence of 10.2 per 1000 inhabitants [95% confidence interval 10.1-10.2], with similar rates in men and women. Estimates were found to increase with age, with an accelerated rise in the second half of the life, which occurred earlier in men than in women. We observed a monotonic gradient of variation with socio-economic deprivation (in non-military metropolitan subjects aged 18-54 years) as well as territorial heterogeneity, with the mountainous centre of France as well as some French overseas departments having the highest prevalence.

CONCLUSIONS

Our results revise upwards the estimation of epilepsy prevalence in France, showing that it now ranks among the highest in developed countries. Our study also confirms the important socio-territorial heterogeneity of the condition that reflects health inequalities in this country.

Association of neighborhood deprivation with white matter connectome abnormalities in temporal lobe epilepsy

OBJECTIVE

Social determinants of health, including the effects of neighborhood disadvantage, impact epilepsy prevalence, treatment, and outcomes. This study characterized the association between aberrant white matter connectivity in temporal lobe epilepsy (TLE) and disadvantage using a US census-based neighborhood disadvantage metric, the Area Deprivation Index (ADI), derived from measures of income, education, employment, and housing quality.

METHODS

Participants including 74 TLE patients (47 male, mean age = 39.2 years) and 45 healthy controls (27 male, mean age = 31.9 years) from the Epilepsy Connectome Project were classified into ADI-defined low and high disadvantage groups. Graph theoretic metrics were applied to multishell connectome diffusion-weighted imaging (DWI) measurements to derive 162 × 162 structural connectivity matrices (SCMs). The SCMs were harmonized using neuroCombat to account for interscanner differences. Threshold-free network-based statistics were used for analysis, and findings were correlated with ADI quintile metrics. A decrease in cross-sectional area (CSA) indicates reduced white matter integrity.

RESULTS

Sex- and age-adjusted CSA in TLE groups was significantly reduced compared to controls regardless of disadvantage status, revealing discrete aberrant white matter tract connectivity abnormalities in addition to apparent differences in graph measures of connectivity and network-based statistics. When comparing broadly defined disadvantaged TLE groups, differences were at trend level. Sensitivity analyses of ADI quintile extremes revealed significantly lower CSA in the most compared to least disadvantaged TLE group.

SIGNIFICANCE

Our findings demonstrate (1) the general impact of TLE on DWI connectome status is larger than the association with neighborhood disadvantage; however, (2) neighborhood disadvantage, indexed by ADI, revealed modest relationships with white matter structure and integrity on sensitivity analysis in TLE. Further studies are needed to explore this relationship and determine whether the white matter relationship with ADI is driven by social drift or environmental influences on brain development. Understanding the etiology and course of the disadvantage-brain integrity relationship may serve to inform care, management, and policy for patients.

The incidence and prevalence of epilepsy in the United Kingdom 2013-2018: A retrospective cohort study of UK primary care data

PURPOSE

The aim of this study was to update overall incidence and prevalence calculations for epilepsy of the United Kingdom (UK) and its constituent nations (England, Northern Ireland, Scotland, and Wales).

METHODS

We used data from primary care practices contributing to the Clinical Practice Research Datalink (CRPD), based on the electronic health records of 14 million patients, representing approximately 20% of the population. CPRD contains data from two different health record systems: the Vision clinical system (CPRD GOLD database) and the EMIS Web® clinical system (CPRD Aurum database). We calculated incidence and prevalence rates with 95% confidence intervals (CIs). Data were stratified by age, gender, deprivation, country (England, Scotland, Wales and Northern Ireland) and region (England only).

RESULTS

In the UK, the estimated overall point prevalence for epilepsy was 9.37 per 1000 persons / year (95% CI 9.34-9.40) and the overall estimated incidence rate was 42.68 per 100,000 person-years (95% 42.18-43.18) using the CPRD GOLD database. In England, the estimated incidence (37.41 (95% CI 36.96-37.83)) and prevalence (8.85 (95% CI 8.83-8.87)) was lower (combined databases) compared to figures for Scotland (incidence 47.76 (95% CI 46.15-49.42)); prevalence 10.13 (95% CI 10.06-10.20)) (CPRD GOLD only), Wales (incidence 54.84 (95% CI 52.79-56.95); prevalence 11.40 (95% CI 11.31-11.49)) (CPRD GOLD only) and Northern Ireland (incidence 46.18 (95% CI 43.13-49.90); prevalence 12.08 (95% CI 11.93-12.23))(combined databases). Prevalence and incidence were higher in more deprived regions.

CONCLUSION

The prevalence and incidence of epilepsy in the UK is broadly in line with other high income countries, showing the usual pattern of high incidence in the young and the old, with a nadir in middle age. The prevalence of epilepsy has fallen slightly since 2011. There is significant geographical variation (between countries and between regions), and a suggestion of a relationship between deprivation and epilepsy which needs further investigation.

Epilepsy and its neurobehavioral comorbidities: Insights gained from animal models

It is well established that epilepsy is associated with numerous neurobehavioral comorbidities, with a bidirectional relationship; people with epilepsy have an increased incidence of depression, anxiety, learning and memory difficulties, and numerous other psychosocial challenges, and the occurrence of epilepsy is higher in individuals with those comorbidities. Although the cause-and-effect relationship is uncertain, a fuller understanding of the mechanisms of comorbidities within the epilepsies could lead to improved therapeutics. Here, we review recent data on epilepsy and its neurobehavioral comorbidities, discussing mainly rodent models, which have been studied most extensively, and emphasize that clinically relevant information can be gained from preclinical models. Furthermore, we explore the numerous potential factors that may confound the interpretation of emerging data from animal models, such as the specific seizure induction method (e.g., chemical, electrical, traumatic, genetic), the role of species and strain, environmental factors (e.g., laboratory environment, handling, epigenetics), and the behavioral assays that are chosen to evaluate the various aspects of neural behavior and cognition. Overall, the interplay between epilepsy and its neurobehavioral comorbidities is undoubtedly multifactorial, involving brain structural changes, network-level differences, molecular signaling abnormalities, and other factors. Animal models are well poised to help dissect the shared pathophysiological mechanisms, neurological sequelae, and biomarkers of epilepsy and its comorbidities.

Longitudinal analysis of the relationship between motor and psychiatric symptoms in idiopathic dystonia

BACKGROUND AND PURPOSE

Although psychiatric diagnoses are recognized in idiopathic dystonia, no previous studies have examined the temporal relationship between idiopathic dystonia and psychiatric diagnoses at scale. Here, we determine rates of psychiatric diagnoses and psychiatric medication prescription in those diagnosed with idiopathic dystsuponia compared to matched controls.

METHODS

A longitudinal population-based cohort study using anonymized electronic health care data in Wales (UK) was conducted to identify individuals with idiopathic dystonia and comorbid psychiatric diagnoses/prescriptions between 1 January 1994 and 31 December 2017. Psychiatric diagnoses/prescriptions were identified from primary and secondary health care records.

RESULTS

Individuals with idiopathic dystonia (n = 52,589) had higher rates of psychiatric diagnosis and psychiatric medication prescription when compared to controls (n = 216,754, 43% vs. 31%, p < 0.001; 45% vs. 37.9%, p < 0.001, respectively), with depression and anxiety being most common (cases: 31% and 28%). Psychiatric diagnoses predominantly predated dystonia diagnosis, particularly in the 12 months prior to diagnosis (incidence rate ratio [IRR] = 1.98, 95% confidence interval [CI] = 1.9-2.1), with an IRR of 12.4 (95% CI = 11.8-13.1) for anxiety disorders. There was, however, an elevated rate of most psychiatric diagnoses throughout the study period, including the 12 months after dystonia diagnosis (IRR = 1.96, 95% CI = 1.85-2.07).

CONCLUSIONS

This study suggests a bidirectional relationship between psychiatric disorders and dystonia, particularly with mood disorders. Psychiatric and motor symptoms in dystonia may have common aetiological mechanisms, with psychiatric disorders potentially forming prodromal symptoms of idiopathic dystonia.

Association between social deprivation and incidence of first seizures and epilepsy: a prospective population based cohort

OBJECTIVE

Epidemiologic studies have investigated whether social deprivation is associated with a higher incidence of epilepsy and results are conflicting, especially in children. The mechanisms underlying a potential association are unclear. This study examines whether there is an association between social deprivation and the incidence of first seizures (unprovoked and provoked) and new diagnosis of epilepsy by comparing incidence across an area-level measure of deprivation in a population-based cohort.

METHODS

Multiple methods of case identification followed by individual case validation and classification were carried out in a defined geographical area (population 542,868) to identify all incident cases of first provoked and first unprovoked seizures and new diagnosis of epilepsy presenting during the calendar year 2017. An area-level relative deprivation index, based on ten indicators from census data, was assigned to each patient according to registered address and categorised into quintiles from most to least deprived.

RESULTS

The annual incidence of first unprovoked seizures (n=372), first provoked seizures (n=189) and new diagnosis of epilepsy (n=336) was highest in the most deprived areas compared to the least deprived areas (incidence ratios of 1·79 (95%CI 1·26, 2·52), 1·55 (95%CI 1·04, 2·32) and 1·83 (95%CI 1·28, 2·62), respectively). This finding was evident in both adults and children and in those with structural and unknown aetiologies of epilepsy.

SIGNIFICANCE

The incidence of first seizures and new diagnosis of epilepsy is associated with more social deprivation. The reason for this higher incidence is likely multifactorial.

Impact of covid-19 on primary care contacts with children and young people aged 0-24 years in England; longitudinal trends study 2015-2020

Background: The NHS response to covid-19 altered provision and access to primary care. Aim: To examine the impact of covid-19 on general practitioner (GP) contacts with children and young people in England. Design and Setting: Longitudinal trends analysis using electronic health records from the Clinical Practice Research Datalink Aurum database. Methods: We included all children and young people younger than 25 years registered with a GP. We compared the number of total, remote and face-to-face contacts during the first UK lockdown (March to June 2020) with the mean contacts for comparable weeks from 2015 to 2019. Results: We examined 47 607 765 GP contacts with 4 307 120 million children and young people. GP contacts fell 41% during the first lockdown compared with previous years. Children aged 1-14 had greater falls in total contacts (>50%) compared with infants and 15-24s. Face-to-face contacts fell by 88% with the greatest falls occurring among children aged 1-14 (> 90%). Remote contacts more than doubled, increasing most in infants (over 2.5 fold). Total contacts for respiratory illnesses fell by 74% whereas contacts for common non-transmissible conditions shifted largely to remote, mitigating the total fall (31%). Conclusion: During the covid-19 pandemic, children and young people’s contact with GPs fell, particularly for face-to-face assessment. This may be explained by a lower prevalence of respiratory illnesses due to fewer social contacts and changing health care seeking behaviour. The large shift to remote contacts mitigated total falls in contacts for some age groups and for common non-transmissible conditions.

Epilepsy mortality in Wales during COVID-19

PURPOSE

The COVID-19 pandemic has increased mortality worldwide and those with chronic conditions may have been disproportionally affected. However, it is unknown whether the pandemic has changed mortality rates for people with epilepsy. We aimed to compare mortality rates in people with epilepsy in Wales during the pandemic with pre-pandemic rates.

METHODS

We performed a retrospective study using individual-level linked population-scale anonymised electronic health records. We identified deaths in people with epilepsy (DPWE), i.e. those with a diagnosis of epilepsy, and deaths associated with epilepsy (DAE), where epilepsy was recorded as a cause of death on death certificates. We compared death rates in 2020 with average rates in 2015-2019 using Poisson models to calculate death rate ratios.

RESULTS

There were 188 DAE and 628 DPWE in Wales in 2020 (death rates: 7.7/100,000/year and 25.7/100,000/year). The average rates for DAE and DPWE from 2015 to 2019 were 5.8/100,000/year and 23.8/100,000/year, respectively. Death rate ratios (2020 compared to 2015-2019) for DAE were 1.34 (95%CI 1.14-1.57, p<0.001) and for DPWE were 1.08 (0.99-1.17, p = 0.09). The death rate ratios for non-COVID deaths (deaths without COVID mentioned on death certificates) for DAE were 1.17 (0.99-1.39, p = 0.06) and for DPWE were 0.96 (0.87-1.05, p = 0.37).

CONCLUSIONS

The significant increase in DAE in Wales during 2020 could be explained by the direct effect of COVID-19 infection. Non-COVID-19 deaths have not increased significantly but further work is needed to assess the longer-term impact.

Adult-onset idiopathic dystonia: A national data-linkage study to determine epidemiological, social deprivation, and mortality characteristics

BACKGROUND AND PURPOSE

Accurate epidemiological information is essential for the improved understanding of dystonia syndromes, as well as better provisioning of clinical services and providing context for diagnostic decision-making. Here, we determine epidemiological, social deprivation, and mortality characteristics of adult-onset idiopathic dystonia in the Welsh population.

METHODS

A retrospective population-based cohort study using anonymized electronic health care data in Wales was conducted to identify individuals with dystonia between 1 January 1994 and 31 December 2017. We developed a case-ascertainment algorithm to determine dystonia incidence and prevalence, as well as characterization of the dystonia cohort, based on social deprivation and mortality.

RESULTS

The case-ascertainment algorithm (79% sensitivity) identified 54,966 cases; of these cases, 41,660 had adult-onset idiopathic dystonia (≥20 years). Amongst the adult-onset form, the median age at diagnosis was 41 years, with males significantly older at time of diagnosis compared to females. Prevalence rates ranged from 0.02% in 1994 to 1.2% in 2017. The average annual incidence was 87.7/100,000/year, increasing from 49.9/100,000/year (1994) to 96.21/100,000/year (2017). In 2017, people with dystonia had a similar life expectancy to the Welsh population.

CONCLUSIONS

We have developed a case-ascertainment algorithm, supported by the introduction of a neurologist-reviewed validation cohort, providing a platform for future population-based dystonia studies. We have established robust population-level prevalence and incidence values for adult-onset idiopathic forms of dystonia, with this reflecting increasing clinical recognition and identification of causal genes. Underlying causes of death mirrored those of the general population, including circulatory disorders, respiratory disorders, cancers, and dementia.

Neurobehavioural comorbidities of epilepsy: towards a network-based precision taxonomy

Cognitive and behavioural comorbidities are prevalent in childhood and adult epilepsies and impose a substantial human and economic burden. Over the past century, the classic approach to understanding the aetiology and course of these comorbidities has been through the prism of the medical taxonomy of epilepsy, including its causes, course, characteristics and syndromes. Although this 'lesion model' has long served as the organizing paradigm for the field, substantial challenges to this model have accumulated from diverse sources, including neuroimaging, neuropathology, neuropsychology and network science. Advances in patient stratification and phenotyping point towards a new taxonomy for the cognitive and behavioural comorbidities of epilepsy, which reflects the heterogeneity of their clinical presentation and raises the possibility of a precision medicine approach. As we discuss in this Review, these advances are informing the development of a revised aetiological paradigm that incorporates sophisticated neurobiological measures, genomics, comorbid disease, diversity and adversity, and resilience factors. We describe modifiable risk factors that could guide early identification, treatment and, ultimately, prevention of cognitive and broader neurobehavioural comorbidities in epilepsy and propose a road map to guide future research.

UK general practice: Continuing to fail in the care of people with epilepsy?

PURPOSE

To review the standard of clinical care of people with epilepsy (PWE) attending UK general practice after epilepsy was removed from the Quality and Outcomes Framework (QOF) in 2014.

METHOD

The case notes of 324 people were reviewed against standards based on National Institute for Health and Care Excellence (NICE), Drug Safety Unit (DSU), and Medicines and Healthcare products Regulatory Agency (MHRA) guidelines.

RESULTS

Annual face-to-face review fell significantly (p = 0.021) after the removal of epilepsy from QOF in 2014. Clinical Commissioning Group (CCG) downloaded review rates fell significantly from 95% in 2010 to only 14% in 2016. One hundred and twenty seven (39%) people had seen their GP, and108 (33%) had not seen any doctor, in the past year. One hundred and seventy three (53%) were under specialist care. Forty nine percent not under specialist care had poor control. Two hundred and fifty four (78%) people were on ASM (Anti-Seizure Medication) associated with poor bone health, of these 41 (16%) were prescribed vitamin D. Fourteen women of childbearing age were taking sodium valproate, of whom only 5 (36%) had written confirmation of being counseled of the associated risks. Fifty six (17%) people were non-complaint with prescription collection, of which 66% had documented poor control. There was a discrepancy between actual face-to-face review rates and the review rates the CCG collected.

CONCLUSION

This study reveals poor annual review rates for PWE in UK primary care, which have fallen further since the removal of epilepsy from QOF. Unmet needs persist for people with poorly controlled epilepsy not under specialist care, bone health, and the care of women of child bearing age. This study, along with previous work, brings into question the concept of shared care for PWE. Clinical Commissioning Groups should consider investing in the training and employment of GPwSIe (GP with Special Interest in epilepsy) and ENS (Epilepsy Nurse Specialists) to work in the community. The Government should examine re-introducing epilepsy back into QOF with measurable clinical targets and adequate remuneration.

Early childhood epilepsies: epidemiology, classification, aetiology, and socio-economic determinants

Epilepsies of early childhood are frequently resistant to therapy and often associated with cognitive and behavioural comorbidity. Aetiology focused precision medicine, notably gene-based therapies, may prevent seizures and comorbidities. Epidemiological data utilizing modern diagnostic techniques including whole genome sequencing and neuroimaging can inform diagnostic strategies and therapeutic trials. We present a 3-year, multicentre prospective cohort study, involving all children under 3 years of age in Scotland presenting with epilepsies. We used two independent sources for case identification: clinical reporting and EEG record review. Capture-recapture methodology was then used to improve the accuracy of incidence estimates. Socio-demographic and clinical details were obtained at presentation, and 24 months later. Children were extensively investigated for aetiology. Whole genome sequencing was offered for all patients with drug-resistant epilepsy for whom no aetiology could yet be identified. Multivariate logistic regression modelling was used to determine associations between clinical features, aetiology, and outcome. Three hundred and ninety children were recruited over 3 years. The adjusted incidence of epilepsies presenting in the first 3 years of life was 239 per 100 000 live births [95% confidence interval (CI) 216-263]. There was a socio-economic gradient to incidence, with a significantly higher incidence in the most deprived quintile (301 per 100 000 live births, 95% CI 251-357) compared with the least deprived quintile (182 per 100 000 live births, 95% CI 139-233), χ2 odds ratio = 1.7 (95% CI 1.3-2.2). The relationship between deprivation and incidence was only observed in the group without identified aetiology, suggesting that populations living in higher deprivation areas have greater multifactorial risk for epilepsy. Aetiology was determined in 54% of children, and epilepsy syndrome was classified in 54%. Thirty-one per cent had an identified genetic cause for their epilepsy. We present novel data on the aetiological spectrum of the most commonly presenting epilepsies of early childhood. Twenty-four months after presentation, 36% of children had drug-resistant epilepsy (DRE), and 49% had global developmental delay (GDD). Identification of an aetiology was the strongest determinant of both DRE and GDD. Aetiology was determined in 82% of those with DRE, and 75% of those with GDD. In young children with epilepsy, genetic testing should be prioritized as it has the highest yield of any investigation and is most likely to inform precision therapy and prognosis. Epilepsies in early childhood are 30% more common than previously reported. Epilepsies of undetermined aetiology present more frequently in deprived communities. This likely reflects increased multifactorial risk within these populations.

Care After Presenting with Seizures (CAPS): An analysis of the impact of a seizure referral pathway and nurse support on neurology referral rates for patients admitted with a seizure

INTRODUCTION

The National Audit of Seizure Management in Hospitals (NASH) identified low referral rates to neurology and epilepsy services after an emergency department attendance or admission with a seizure.

METHODS

National Health Service Secondary Users Service (SUS) data were used to assess the impact of a seizure pathway at seven hospitals in Cheshire & Merseyside, which was implemented in 2014. Three of these hospitals also had a nurse employed part-time to support the pathway. Patients admitted with a seizure between 2011 and 2018 inclusive were identified using an algorithm based on ICD-10 codes, and the primary outcome was a neurology referral within 3 months of admission. Regression models were used to assess the impact of age, deprivation and comorbidity on post admission clinic referral rates.

RESULTS

13,285 admissions with seizure were included in the analysis. 5,677 had not attended a neurology clinic appointment in the 12 months before the admission. The percentage of whom that were offered an appointment following the admission was: 16.0% before the pathway and 35.9% with the nurse-supported pathway, which was significant in the regression model. 4,700 admissions had attended a neurology clinic appointment in the 12 months before the admission. Of this group, the percentage of whom that were offered an appointment following the admission was: 55.2% before the pathway and 62.4% with the nurse-supported pathway, an increase that was not significant in the regression model. The regression models identified significant health inequalities whereby older patients, those with comorbidities and those living in deprived areas were significantly less likely to be referred.

CONCLUSION

Neurology out-patient appointment rates following an admission with seizures are low, worryingly so for those with no neurology appointment in the previous 12 months. A nurse-supported pathway can improve appointment rates, but the effect is modest. Further service redesign is required; the impact of which should be rigorously evaluated.

Impact of schizophrenia genetic liability on the association between schizophrenia and physical illness: data-linkage study

BACKGROUND

Individuals with schizophrenia are at higher risk of physical illnesses, which are a major contributor to their 20-year reduced life expectancy. It is currently unknown what causes the increased risk of physical illness in schizophrenia.

AIMS

To link genetic data from a clinically ascertained sample of individuals with schizophrenia to anonymised National Health Service (NHS) records. To assess (a) rates of physical illness in those with schizophrenia, and (b) whether physical illness in schizophrenia is associated with genetic liability.

METHOD

We linked genetic data from a clinically ascertained sample of individuals with schizophrenia (Cardiff Cognition in Schizophrenia participants, n = 896) to anonymised NHS records held in the Secure Anonymised Information Linkage (SAIL) databank. Physical illnesses were defined from the General Practice Database and Patient Episode Database for Wales. Genetic liability for schizophrenia was indexed by (a) rare copy number variants (CNVs), and (b) polygenic risk scores.

RESULTS

Individuals with schizophrenia in SAIL had increased rates of epilepsy (standardised rate ratio (SRR) = 5.34), intellectual disability (SRR = 3.11), type 2 diabetes (SRR = 2.45), congenital disorders (SRR = 1.77), ischaemic heart disease (SRR = 1.57) and smoking (SRR = 1.44) in comparison with the general SAIL population. In those with schizophrenia, carrier status for schizophrenia-associated CNVs and neurodevelopmental disorder-associated CNVs was associated with height (P = 0.015-0.017), with carriers being 7.5-7.7 cm shorter than non-carriers. We did not find evidence that the increased rates of poor physical health outcomes in schizophrenia were associated with genetic liability for the disorder.

CONCLUSIONS

This study demonstrates the value of and potential for linking genetic data from clinically ascertained research studies to anonymised health records. The increased risk for physical illness in schizophrenia is not caused by genetic liability for the disorder.

A nationwide, retrospective, data-linkage, cohort study of epilepsy and incident dementia

OBJECTIVE

To determine the association of epilepsy with incident dementia by conducting a nationwide, retrospective data-linkage, cohort study to examine whether the association varies according to dementia subtypes and to investigate whether risk factors modify the association.

METHODS

We used linked health data from hospitalization, mortality records, and primary care consultations to follow up 563,151 Welsh residents from their 60th birthday to estimate dementia rate and associated risk factors. Dementia, epilepsy, and covariates (medication, smoking, comorbid conditions) were classified with the use of previously validated code lists. We studied rate of dementia and dementia subtypes in people with epilepsy (PWE) and without epilepsy using (stratified) Kaplan-Meier plots and flexible parametric survival models.

RESULTS

PWE had a 2.5 (95% confidence interval [CI] 2.3-2.6) times higher hazard of incident dementia, a 1.6 (95% CI 1.4-1.8) times higher hazard of incident Alzheimer disease (AD), and a 3.1 (95% CI 2.8-3.4) times higher hazard of incident Vascular dementia (VaD). A history of stroke modified the increased incidence in PWE. PWE who were first diagnosed at ≤25 years of age had a dementia rate similar to that of those diagnosed later in life. PWE who had ever been prescribed sodium valproate compared to those who had not were at higher risk of dementia (hazard ratio [HR] 1.6, 99% CI 1.4-1.9) and VaD (HR 1.7, 99% CI 1.4-2.1) but not AD (HR 1.2, 99% CI 0.9-1.5).

CONCLUSION

PWE compared to those without epilepsy have an increased dementia risk.

Network, clinical and sociodemographic features of cognitive phenotypes in temporal lobe epilepsy

This study explored the taxonomy of cognitive impairment within temporal lobe epilepsy and characterized the sociodemographic, clinical and neurobiological correlates of identified cognitive phenotypes. 111 temporal lobe epilepsy patients and 83 controls (mean ages 33 and 39, 57% and 61% female, respectively) from the Epilepsy Connectome Project underwent neuropsychological assessment, clinical interview, and high resolution 3T structural and resting-state functional MRI. A comprehensive neuropsychological test battery was reduced to core cognitive domains (language, memory, executive, visuospatial, motor speed) which were then subjected to cluster analysis. The resulting cognitive subgroups were compared in regard to sociodemographic and clinical epilepsy characteristics as well as variations in brain structure and functional connectivity. Three cognitive subgroups were identified (intact, language/memory/executive function impairment, generalized impairment) which differed significantly, in a systematic fashion, across multiple features. The generalized impairment group was characterized by an earlier age at medication initiation (P < 0.05), fewer patient (P < 0.001) and parental years of education (P < 0.05), greater racial diversity (P < 0.05), and greater number of lifetime generalized seizures (P < 0.001). The three groups also differed in an orderly manner across total intracranial (P < 0.001) and bilateral cerebellar cortex volumes (P < 0.01), and rate of bilateral hippocampal atrophy (P < 0.014), but minimally in regional measures of cortical volume or thickness. In contrast, large-scale patterns of cortical-subcortical covariance networks revealed significant differences across groups in global and local measures of community structure and distribution of hubs. Resting-state fMRI revealed stepwise anomalies as a function of cluster membership, with the most abnormal patterns of connectivity evident in the generalized impairment group and no significant differences from controls in the cognitively intact group. Overall, the distinct underlying cognitive phenotypes of temporal lobe epilepsy harbor systematic relationships with clinical, sociodemographic and neuroimaging correlates. Cognitive phenotype variations in patient and familial education and ethnicity, with linked variations in total intracranial volume, raise the question of an early and persisting socioeconomic-status related neurodevelopmental impact, with additional contributions of clinical epilepsy factors (e.g., lifetime generalized seizures). The neuroimaging features of cognitive phenotype membership are most notable for disrupted large scale cortical-subcortical networks and patterns of functional connectivity with bilateral hippocampal and cerebellar atrophy. The cognitive taxonomy of temporal lobe epilepsy appears influenced by features that reflect the combined influence of socioeconomic, neurodevelopmental and neurobiological risk factors.

GP prescribing in Northern Ireland by deprivation index: retrospective analysis

Objective

In the present study, we sought to explore the relationship between socioeconomic status and prescribing magnitude and cost in primary care throughout Northern Ireland.

Design

We performed a retrospective data analysis of general practitioner (GP) prescribing using open-source databases with data collected from May to October 2019 to determine the number of prescriptions and cost of drugs and drug classes by area, ranking these by deprivation index. We used Kendall’s tau to quantify the relationship between prescribing and deprivation.

Setting

We analysed open-source data collected from 325 GP practices in Northern Ireland during the period from May to October 2019.

Participants

We analysed a total of 2 764 303 prescriptions signed during our study period.

Results

Our study indicates a clear trend of increased overall spending per patient (r=−0.1232, p=0.02) and number of prescriptions per patient (r=−0.3440, p<0.001) in areas of higher deprivation. The mean cost per item was higher in less deprived areas (r=0.3809, p<0.001). Overall, £13.79 more was spent and 3.5 more items were prescribed per patient in the most compared with the least deprived decile, although more expensive items tended to be prescribed in areas with lower socioeconomic deprivation (£11.27 per item vs £9.20 per item). We found a statistically significant correlation of prescribing of key drug classes, such as bronchodilators, antidepressants and drugs used to treat diabetes, among others, with greater deprivation. Prescribing of vaccines and drugs used in the treatment of glaucoma was correlated with lower deprivation.

Conclusion

We provide an exploration of the correlation of prescribing with deprivation by analysing all prescriptions signed within a 6-month period in Northern Ireland. Our study broadly agrees with published literature, although a few notable exceptions are highlighted. We provide evidence of discrepancies in medication cost between areas of differing deprivation and suggest possible explanations for these trends. This information will be valuable for future investigation of disease prevalence, as well as targeting of patient education and future funding.

Public preferences regarding data linkage for research: a discrete choice experiment comparing Scotland and Sweden

BACKGROUND

There are increasing examples of linking data on healthcare resource use and patient outcomes from different sectors of health and social care systems. Linked data are generally anonymised, meaning in most jurisdictions there are no legal restrictions to their use in research conducted by public or private organisations. Secondary use of anonymised linked data is contentious in some jurisdictions but other jurisdictions are known for their use of linked data. The publics' perceptions of the acceptability of using linked data is likely to depend on a number of factors. This study aimed to quantify the preferences of the public to understand the factors that affected views about types of linked data and its use in two jurisdictions.

METHOD

An online discrete choice experiment (DCE) previously conducted in Scotland was adapted and replicated in Sweden. The DCE was designed, comprising five attributes, to elicit the preferences from a representative sample of the public in both jurisdictions. The five attributes (number of levels) were: type of researcher using linked data (four); type of data being linked (four); purpose of the research (three); use of profit from using linked data (four); who oversees the research (four). Each DCE contained 6 choice-sets asking respondents to select their preferred option from two scenarios or state neither were acceptable. Background questions included socio-demographics. DCE data were analysed using conditional and heteroskedastic conditional logit models to create forecasts of acceptability.

RESULTS

The study sample comprised members of the public living in Scotland (n = 1004) and Sweden (n = 974). All five attributes were important in driving respondents' choices. Swedish and Scottish preferences were mostly homogenous with the exception of 'who oversees the research using linked data', which had relatively less impact on the choices observed from Scotland. For a defined 'typical' linked data scenario, the probability (on average) of acceptance was 85.7% in Sweden and 82.4% in Scotland.

CONCLUSION

This study suggests that the public living in Scotland and Sweden are open to using anonymised linked data in certain scenarios for research purposes but some caution is advisable if the anonymised linked data joins health to non-health data.

Temporal trends in incidence of Rolandic epilepsy, prevalence of comorbidities and prescribing trends: birth cohort study

OBJECTIVE

To examine temporal trends in incidence of Rolandic epilepsy (RE), prevalence of comorbidities and antiepileptic drug (AED) prescribing patterns.

DESIGN

Retrospective cohort study.

SETTING

The UK.

PATIENTS

Children aged 0-16 years born 1994-2012 were followed from birth until September 2017, transfer to another general practitioner practice or death or practice withdrawal from The Health Improvement Network (THIN), whichever occurred first.

MAIN OUTCOME MEASURES

Incidence of RE, prevalence of comorbidity and AED prescribing patterns. Read codes for comorbidities and AEDs were adapted from other UK population-based epilepsy studies.

RESULTS

There were 379 children with first RE event recorded between 2000 and 2014 from active THIN practices with available mid-year population counts. Crude annual incidence across all years was 5.31/100 000 (95% CI 4.81 to 5.88). There was no significant time trend in adjusted incidence rate ratios (aIRR) (0.99/year, 95% CI 0.96 to 1.02). Males had higher aIRR (1.48, 95% CI 1.20 to 1.82) as did children aged 6-8 and 9-11 years compared with 4-5 years (aIRR 2.43, 95% CI 1.73 to 3.40; aIRR 2.77, 95% CI 1.97 to 3.90, respectively). There was recorded comorbidity in 12% with 6% with a recorded diagnosis of pervasive developmental disorder. Half of children with RE had a record of being prescribed AEDs.

CONCLUSIONS

UK incidence of RE has remained stable with crude incidence of 5/100 000/year. Carers and clinicians need to be aware that comorbidities may exist, particularly pervasive developmental disorders. Carbamazepine is consistently the most commonly prescribed AED for RE in the UK.

Area deprivation, urbanicity, severe mental illness and social drift - A population-based linkage study using routinely collected primary and secondary care data

We investigated whether associations between area deprivation, urbanicity and elevated risk of severe mental illnesses (SMIs, including schizophrenia and bipolar disorder) is accounted for by social drift or social causation. We extracted primary and secondary care electronic health records from 2004 to 2015 from a population of 3.9 million. We identified prevalent and incident individuals with SMIs and their level of deprivation and urbanicity using the Welsh Index of Multiple Deprivation (WIMD) and urban/rural indicator. The presence of social drift was determined by whether odds ratios (ORs) from logistic regression is greater than the incidence rate ratios (IRRs) from Poisson regression. Additionally, we performed longitudinal analysis to measure the proportion of change in deprivation level and rural/urban residence 10 years after an incident diagnosis of SMI and compared it to the general population using standardised rate ratios (SRRs). Prevalence and incidence of SMIs were significantly associated with deprivation and urbanicity (all ORs and IRRs significantly >1). ORs and IRRs were similar across all conditions and cohorts (ranging from 1.1 to 1.4). Results from the longitudinal analysis showed individuals with SMIs are more likely to move compared to the general population. However, they did not preferentially move to more deprived or urban areas. There was little evidence of downward social drift over a 10-year period. These findings have implications for the allocation of resources, service configuration and access to services in deprived communities, as well as, for broader public health interventions addressing poverty, and social and environmental contexts.

Epilepsy deaths: Learning from health service delivery and trying to reduce risk

Two recent UK reports have highlighted data of concern in relation to potentially preventable epilepsy deaths. Public Health England, an executive agency of the Government Department of Health, using National Health Service data from 2001 to 2014 reported a rise in direct age-standardised mortality for epilepsy-associated deaths, in contrast to a reduction in all-cause deaths over the same period. Premature death was seen in people aged below 50 years, especially in men, and where epilepsy was a contributory cause rather than an association. The Scottish Epilepsy Deaths Study, analysing deaths between 2009 and 2016, similarly found death in those with epilepsy was significantly higher than the matched population below the age of 54, especially between the ages of 16 and 24 (6 times higher). Sudden unexpected death in epilepsy accounted for 38% of epilepsy-related deaths under the age of 45. Both studies found a strong relationship between risk of death and deprivation; we discuss the implications of these and other data for planning service delivery and improving epilepsy care. This paper is for the Special Issue: Prevent 21: SUDEP Summit - Time to Listen.

SUDEP and mortality in epilepsy: The role of routinely collected healthcare data, registries, and health inequalities

Routinely collected data are a powerful research resource and offer the opportunity to further our understanding of epilepsy mortality and Sudden Unexpected Death in Epilepsy (SUDEP). The advantages of using routinely collected data include that it often covers whole populations, is already collected, and can be easily linked to other data sources. A significant disadvantage is the difficulty in obtaining accurate causes of death and correctly identifying cases of SUDEP. Using and linking data from epilepsy death registries can improve the quality of mortality data for research. Epilepsy prevalence, incidence, and mortality rates are associated with socioeconomic deprivation. Further research into understanding the link between deprivation and epilepsy mortality could lead to ways to reduce epilepsy mortality. This paper is for the Special Issue :Prevent 21: SUDEP Summit - Time to Listen.

Risk of Unnatural Mortality in People With Epilepsy

Importance

People with epilepsy are at increased risk of mortality, but, to date, the cause-specific risks of all unnatural causes have not been reported.

Objective

To estimate cause-specific unnatural mortality risks in people with epilepsy and to identify the medication types involved in poisoning deaths.

Design, Setting, and Participants

This population-based cohort study used 2 electronic primary care data sets linked to hospitalization and mortality records, the Clinical Practice Research Datalink (CPRD) in England (from January 1, 1998, to March 31, 2014) and the Secure Anonymised Information Linkage (SAIL) Databank in Wales (from January 1, 2001, to December 31, 2014). Each person with epilepsy was matched on age (within 2 years), sex, and general practice with up to 20 individuals without epilepsy. Unnatural mortality was determined using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes V01 through Y98 in the Office for National Statistics mortality records. Hazard ratios (HRs) were estimated in each data set using a stratified Cox proportional hazards model, and meta-analyses were conducted using DerSimonian and Laird random-effects models. The analysis was performed from January 5, 2016, to November 16, 2017.

Exposures

People with epilepsy were identified using primary care epilepsy diagnoses and associated antiepileptic drug prescriptions.

Main Outcomes and Measures

Hazard ratios (HRs) for unnatural mortality and the frequency of each involved medication type estimated as a percentage of all medication poisoning deaths.

Results

In total, 44 678 individuals in the CPRD and 14 051 individuals in the SAIL Databank were identified in the prevalent epilepsy cohorts, and 891 429 (CPRD) and 279 365 (SAIL) individuals were identified in the comparison cohorts. In both data sets, 51% of the epilepsy and comparison cohorts were male, and the median age at entry was 40 years (interquartile range, 25-60 years) in the CPRD cohorts and 43 years (interquartile range, 24-64 years) in the SAIL cohorts. People with epilepsy were significantly more likely to die of any unnatural cause (HR, 2.77; 95% CI, 2.43-3.16), unintentional injury or poisoning (HR, 2.97; 95% CI, 2.54-3.48) or suicide (HR, 2.15; 95% CI, 1.51-3.07) than people in the comparison cohort. Particularly large risk increases were observed in the epilepsy cohorts for unintentional medication poisoning (HR, 4.99; 95% CI, 3.22-7.74) and intentional self-poisoning with medication (HR, 3.55; 95% CI, 1.01-12.53). Opioids (56.5% [95% CI, 43.3%-69.0%]) and psychotropic medication (32.3% [95% CI, 20.9%-45.3%)] were more commonly involved than antiepileptic drugs (9.7% [95% CI, 3.6%-19.9%]) in poisoning deaths in people with epilepsy.

Conclusions and Relevance

Compared with people without epilepsy, people with epilepsy are at increased risk of unnatural death and thus should be adequately advised about unintentional injury prevention and monitored for suicidal ideation, thoughts, and behaviors. The suitability and toxicity of concomitant medication should be considered when prescribing for comorbid conditions.

High-resolution mapping of epilepsy prevalence, ambulance use, and socioeconomic deprivation in an urban area of Sweden

OBJECTIVE

Geographic differences in epilepsy prevalence between areas of different socioeconomic standing have been demonstrated in the United Kingdom, but knowledge from other health care systems is scarce. Our objective was to compare epilepsy prevalence and emergency medical service (EMS) assignments for seizures in areas of different socioeconomic standings in the urban area of Gothenburg.

METHODS

Register-based study in Gothenburg (population 690 000), the second largest city in Sweden. Epilepsy cases were identified in the comprehensive national patient register in 2014-2015. EMS assignments were identified in the EMS dispatch system in 2013-2018. Socioeconomic variables were mean income and proportion of welfare recipients.

RESULTS

Significant correlations were seen between epilepsy prevalence and the proportion of welfare recipients (r = .49, P = .0014) and annual income per capita (r = -.42, P = .0071). There were 7907 assignments for seizures during the study years. GPS-based analysis showed that most assignments occurred in the city center. In addition, several high-density areas correlated with areas with a high proportion of inhabitants receiving welfare. Correlation analysis showed significant associations between the number of EMS assignments per capita and the proportion of welfare recipients (r = .31, P < .0001) and income (r = -.19, P < .0001). When comparing representative areas, a greater proportion of assignments was given the highest priority in high status areas compared to low status areas, both by the dispatch center and EMS clinicians on scene.

SIGNIFICANCE

Our findings that epilepsy prevalence and seizure frequency differ with socioeconomic status on a microgeographic level considerably strengthen the generalizability of previous observations across different health care systems. Differences in priority may reflect health utilization behavior or access to neurologic care.

Socioeconomic status and disability progression in multiple sclerosis: A multinational study

OBJECTIVE

To examine the association between socioeconomic status (SES) and disability outcomes and progression in multiple sclerosis (MS).

METHODS

Health administrative and MS clinical data were linked for 2 cohorts of patients with MS in British Columbia (Canada) and South East Wales (UK). SES was measured at MS symptom onset (±3 years) based on neighborhood-level average income. The association between SES at MS onset and sustained and confirmed Expanded Disability Status Scale (EDSS) 6.0 and 4.0 and onset of secondary progression of MS (SPMS) were assessed using Cox proportional hazards models. EDSS scores were also examined via linear regression, using generalized estimating equations (GEE) with an exchangeable working correlation. Models were adjusted for onset age, sex, initial disease course, and disease-modifying drug exposure. Random effect models (meta-analysis) were used to combine results from the 2 cohorts.

RESULTS

A total of 3,113 patients with MS were included (2,069 from Canada; 1,044 from Wales). A higher SES was associated with a lower hazard of reaching EDSS 6.0 (adjusted hazard ratio [aHR] 0.90, 95% confidence interval [CI] 0.89-0.91), EDSS 4.0 (aHR 0.93, 0.88-0.98), and SPMS (aHR 0.94, 0.88-0.99). The direction of findings was similar when all EDSS scores were included (GEE: β = -0.13, -0.18 to -0.08).

CONCLUSIONS

Lower neighborhood-level SES was associated with a higher risk of disability progression. Reasons for this association are likely to be complex but could include factors amenable to modification, such as lifestyle or comorbidity. Our findings are relevant for planning and development of MS services.

Managing epilepsy in austerity - Evaluating the utility and value of the epilepsy specialist nurse in an open access model of service delivery. Aneurin Bevan Epilepsy Specialist Team (A.B.E.S.T.)

PURPOSE

Healthcare organisations in the UK primarily measure clinical activity from data collected on numbers of attendances at outpatient clinics, inpatient admissions and procedures performed etc. Telephone contacts with patients are not typically measured as clinical activity. This service evaluation examines the utility and value of the Epilepsy Specialist Nurse (ESN) within an innovative 'Open Access Model', giving a breakdown of clinical workload and outcomes.

METHODS

A retrospective service evaluation analysing all patient encounters made by the ESN and their outcomes, over a 3-month period from the 01/02/2017 to 30/04/2017.

RESULTS

During the 3-month data collection period there were 620 patient encounters with 251 different patients. Nurse-led clinic appointments and telephone calls were the two most common types of encounter. Eighteen percent of ESN time was spent on the phone directly addressing patient concerns (368 encounters). Of these calls, 72% led to prevention of a clinic appointment (268 appointments avoided) while only 22% needed a subsequent clinic appointment. The most common outcome of telephone encounters was 'medication management' (25%).

CONCLUSIONS

The evaluation demonstrates that timely intervention by telephone reduces the need for outpatient appointments and leads to treatment changes being implemented quickly to address individual need.

Risk of Unnatural Mortality in Epilepsy

[Box: see text]

Risk factors for self-harm in people with epilepsy

OBJECTIVE

To estimate the risk of self-harm in people with epilepsy and identify factors which influence this risk.

METHODS

We identified people with incident epilepsy in the Clinical Practice Research Datalink, linked to hospitalization and mortality data, in England (01/01/1998-03/31/2014). In Phase 1, we estimated risk of self-harm among people with epilepsy, versus those without, in a matched cohort study using a stratified Cox proportional hazards model. In Phase 2, we delineated a nested case-control study from the incident epilepsy cohort. People who had self-harmed (cases) were matched with up to 20 controls. From conditional logistic regression models, we estimated relative risk of self-harm associated with mental and physical illness comorbidity, contact with healthcare services and antiepileptic drug (AED) use.

RESULTS

Phase 1 included 11,690 people with epilepsy and 215,569 individuals without. We observed an adjusted hazard ratio of 5.31 (95% CI 4.08-6.89) for self-harm in the first year following epilepsy diagnosis and 3.31 (95% CI 2.85-3.84) in subsequent years. In Phase 2, there were 273 cases and 3790 controls. Elevated self-harm risk was associated with mental illness (OR 4.08, 95% CI 3.06-5.42), multiple general practitioner consultations, treatment with two AEDs versus monotherapy (OR 1.84, 95% CI 1.33-2.55) and AED treatment augmentation (OR 2.12, 95% CI 1.38-3.26).

CONCLUSION

People with epilepsy have elevated self-harm risk, especially in the first year following diagnosis. Clinicians should adequately monitor these individuals and be especially vigilant to self-harm risk in people with epilepsy and comorbid mental illness, frequent healthcare service contact, those taking multiple AEDs and during treatment augmentation.

Association between environmental exposure to pesticides and epilepsy

There is increasing evidence of an association between long-term environmental exposure to pesticides and neurodegenerative disorders; however, the relationship with epilepsy has not been addressed thus far. This study was aimed at determining the prevalence and risk of developing epilepsy among people from South-East Spain living in areas of high vs. low exposure to pesticides based on agronomic data. The study population consisted of 4007 subjects with a diagnosis of epilepsy and 580,077 control subjects adjusted for age, sex and geographical area. Data were collected from hospital records of the Spanish health care system (basic minimum dataset) between the years 1998 and 2010. The prevalence of epilepsy was significantly higher in areas of greater pesticide use relative to areas of lesser use. Overall, an increased risk of epilepsy was observed in the population living in areas of high vs. low use of pesticides (OR: 1.65; p < 0.001). Although this study was exploratory in nature, the results suggest that environmental exposure to pesticides might increase the risk of having epilepsy.

Educational attainment of children born to mothers with epilepsy

OBJECTIVE

Small prospective studies have identified that children exposed to valproate in utero have poorer scores on cognitive testing. We wanted to identify whether children exposed to antiepileptic drugs (AEDs) in utero have poorer school performance.

METHODS

We used anonymised, linked, routinely collected healthcare records to identify children born to mothers with epilepsy. We linked these children to their national attainment Key Stage 1 (KS1) tests in mathematics, language and science at the age of 7 and compared them with matched children born to mothers without epilepsy, and with the national KS1 results. We used the core subject indicator (CSI) as an outcome measure (the proportion of children achieving a minimum standard in all subjects) and the results in individual subjects.

RESULTS

We identified 440 children born to mothers with epilepsy with available KS1 results. Compared with a matched control group, fewer children with mothers being prescribed sodium valproate during pregnancy achieved the national minimum standard in CSI (-12.7% less than the control group), mathematics (-12.1%), language (-10.4%) and in science (-12.2%). Even fewer children with mothers being prescribed multiple AEDs during pregnancy achieved a national minimum standard: CSI (by -20.7% less than the control group), mathematics (-21.9%), language (-19.3%) and science (-19.4%). We did not observe any significant difference in children whose mothers were prescribed carbamazepine or were not taking an AED when compared with the control group.

CONCLUSIONS

In utero exposure to AEDs in combination, or sodium valproate alone, is associated with a significant decrease in attainment in national educational tests for 7-year-old children compared with both a matched control group and the all-Wales national average. These results give further support to the cognitive and developmental effects of in utero exposure to sodium valproate as well as multiple AEDs, which should be balanced against the need for effective seizure control for women during pregnancy.

Valproate: life-saving, life-changing

Antiepileptic medications, and valproate principally, are commonly prescribed teratogens. There is significant concern that we are not doing enough to educate clinicians and potential parents about the risks of valproate in pregnancy. There is clear advice from the Medicines and Healthcare products Regulatory Agency and the International League Against Epilepsy about the risks of valproate exposure in utero Reviews and guidelines that are focused on fetal risk, however, fall short in being able to fully replicate the complexity of a real clinical decision. Valproate is certainly life-changing if your child is one of the 10% with a major malformation or 30-40% with a neurodevelopmental disorder, but valproate is also potentially life-saving in the context of ensuring the best possible seizure control for some mothers with epilepsy. There are significant knowledge gaps regarding the risks to mothers who elect to take another drug, or to mother and baby if she comes off medication entirely. We also should be doing more to reduce rates of sudden unexpected death in epilepsy (SUDEP), which is recognised as a key target when evaluating all maternal deaths.

New differentially expressed genes and differential DNA methylation underlying refractory epilepsy

Epigenetics underlying refractory epilepsy is poorly understood, especially in patients without distinctive genetic alterations. DNA methylation may affect gene expression in epilepsy without affecting DNA sequences. Herein, we analyzed genome-wide DNA methylation and gene expression in brain tissues of 10 patients with refractory epilepsy using methylated DNA immunoprecipitation linked with sequencing and mRNA Sequencing. Diverse distribution of differentially methylated genes was found in X chromosome, while differentially methylated genes appeared rarely in Y chromosome. 62 differentially expressed genes, such as MMP19, AZGP1, DES, and LGR6 were correlated with refractory epilepsy for the first time. Although general trends of differentially enriched gene ontology terms and Kyoto Encyclopedia of Genes and Genome pathways in this study are consistent with previous researches, differences also exist in many specific gene ontology terms and Kyoto Encyclopedia of Genes and Genome pathways. These findings provide a new genome-wide profiling of DNA methylation and gene expression in brain tissues of patients with refractory epilepsy, which may provide a basis for further study on the etiology and mechanisms of refractory epilepsy.

Validating epilepsy diagnoses in routinely collected data

•

Cases with and without epilepsy were linked with anonymised primary care data.

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Primary care diagnosis and drug codes accurately identify the cases with epilepsy.

•

Drug codes alone can be used to identify children with epilepsy.

•

Combining drug and diagnosis codes for adults and children increases accuracy.

Purpose

Anonymised, routinely-collected healthcare data is increasingly being used for epilepsy research. We validated algorithms using general practitioner (GP) primary healthcare records to identify people with epilepsy from anonymised healthcare data within the Secure Anonymised Information Linkage (SAIL) databank in Wales, UK.

Method

A reference population of 150 people with definite epilepsy and 150 people without epilepsy was ascertained from hospital records and linked to records contained within SAIL (containing GP records for 2.4 million people). We used three different algorithms, using combinations of GP epilepsy diagnosis and anti-epileptic drug (AED) prescription codes, to identify the reference population.

Results

Combining diagnosis and AED prescription codes had a sensitivity of 84% (95% ci 77–90) and specificity of 98% (95–100) in identifying people with epilepsy; diagnosis codes alone had a sensitivity of 86% (80–91) and a specificity of 97% (92–99); and AED prescription codes alone achieved a sensitivity of 92% (70–83) and a specificity of 73% (65–80). Using AED codes only was more accurate in children achieving a sensitivity of 88% (75–95) and specificity of 98% (88–100).

Conclusion

GP epilepsy diagnosis and AED prescription codes can be confidently used to identify people with epilepsy using anonymised healthcare records in Wales, UK.