An epidemiological study of epilepsy in Hong Kong SAR, China

An estimation of global volume of surgically treatable epilepsy based on a systematic review and meta-analysis of epilepsy

OBJECTIVE

Epilepsy is one of the most common neurological disorders, yet its global surgical burden has yet to be characterized. The authors sought to compile the most current epidemiological data to quantify global prevalence and incidence, and estimate global surgically treatable epilepsy. Understanding regional and global epilepsy trends and potential surgical volume is crucial for future policy efforts and resource allocation.

METHODS

The authors performed a systematic literature review and meta-analysis to determine the global incidence, lifetime prevalence, and active prevalence of epilepsy; to estimate surgically treatable epilepsy volume; and to evaluate regional trends by WHO regions and World Bank income levels. Data were extracted from all population-based studies with prespecified methodological quality across all countries and demographics, performed between 1990 and 2016 and indexed on PubMed, EMBASE, and Cochrane. The current and annual new case volumes for surgically treatable epilepsy were derived from global epilepsy prevalence and incidence.

RESULTS

This systematic review yielded 167 articles, across all WHO regions and income levels. Meta-analysis showed a raw global prevalence of lifetime epilepsy of 1099 per 100,000 people, whereas active epilepsy prevalence is slightly lower at 690 per 100,000 people. Global incidence was found to be 62 cases per 100,000 person-years. The meta-analysis predicted 4.6 million new cases of epilepsy annually worldwide, a prevalence of 51.7 million active epilepsy cases, and 82.3 million people with any lifetime epilepsy diagnosis. Differences across WHO regions and country incomes were significant. The authors estimate that currently 10.1 million patients with epilepsy may be surgical treatment candidates, and 1.4 million new surgically treatable epilepsy cases arise annually. The highest prevalences are found in Africa and Latin America, although the highest incidences are reported in the Middle East and Latin America. These regions are primarily low- and middle-income countries; as expected, the highest disease burden falls disproportionately on regions with the fewest healthcare resources.

CONCLUSIONS

Understanding of the global epilepsy burden has evolved as more regions have been studied. This up-to-date worldwide analysis provides the first estimate of surgical epilepsy volume and an updated comprehensive overview of current epidemiological trends. The disproportionate burden of epilepsy on low- and middle-income countries will require targeted diagnostic and treatment efforts to reduce the global disparities in care and cost. Quantifying global epilepsy provides the first step toward restructuring the allocation of healthcare resources as part of global healthcare system strengthening.

Epilepsy in Asia: Disease burden, management barriers, and challenges

This article reviews the burden of epilepsy in Asia, the challenges faced by people with epilepsy, and the management of epilepsy. Comparison is made with other parts of the world. For this narrative review, data were collected using specified search criteria. Articles investigating the epidemiology of epilepsy, diagnosis, comorbidities and associated mortality, stigmatization, and treatment were included. Epilepsy is a global health care issue affecting up to 70 million people worldwide. Nearly 80% of people with epilepsy live in low- and middle-income countries with limited resources. People with epilepsy are prone to physical and psychological comorbidities, including anxiety and depression, which can negatively impact their quality of life. Furthermore, people with epilepsy are at higher risk of premature death than people without epilepsy. Discrimination or stigmatization of people with epilepsy is common in Asia and can affect their education, work, and marriage opportunities. Access to epilepsy treatment varies throughout Asia. Although highly advanced treatment is available in some countries, up to 90% of people with epilepsy are not adequately treated or are not treated with conventional antiepileptic therapy in resource-limited countries. People in remote areas often do not receive any epilepsy care. First-generation antiepileptic drugs (AEDs) are available, but usually only in urban areas, and second-generation AEDs are not available in all countries. Newer AEDs tend to have more favorable safety profiles than first-generation AEDs and provide options to tailor therapy for individual patients, especially those with comorbidities. Active epilepsy surgery centers are present in some countries, although epilepsy surgery is often underutilized given the number of patients who could benefit. Further epidemiologic research is needed to provide accurate epilepsy data across the Asian region. Coordinated action is warranted to improve access to treatment and care.

Estimating the Prevalence of Treated Epilepsy Using Administrative Health Data and Its Validity: ESSENCE Study

Background and Purpose

Few of the epidemiologic studies of epilepsy have utilized well-validated nationwide databases. We estimated the nationwide prevalence of treated epilepsy based on a comprehensive medical payment database along with diagnostic validation.

Methods

We collected data on patients prescribed of antiepileptic drugs (AEDs) from the Health Insurance Review and Assessment service, which covers the entire population of Korea. To assess the diagnostic validity, a medical records survey was conducted involving 6,774 patients prescribed AEDs from 43 institutions based on regional clusters and referral levels across the country. The prevalence of treated epilepsy was estimated by projecting the diagnostic validity on the number of patients prescribed AEDs.

Results

The mean positive predictive value (PPV) for epilepsy was 0.810 for those prescribed AEDs with diagnostic codes that indicate epilepsy or seizure (Diagnosis-E), while it was 0.066 for those without Diagnosis-E. The PPV tended to decrease with age in both groups, with lower values seen in females. The prevalence was 3.84 per 1,000, and it was higher among males, children, and the elderly.

Conclusions

The prevalence of epilepsy in Korea was comparable to that in other East Asian countries. The diagnostic validity of administrative health data varies depending on the method of case ascertainment, age, and sex. The prescriptions of AEDs even without relevant diagnostic codes should be considered as a tracer for epilepsy.

Prevalence and risk factors of epilepsy among school children in Kayseri City Center, an urban area in Central Anatolia, Turkey

PURPOSE

To investigate the prevalence of epilepsy in schoolchildren aged 7-17 in the province of Kayseri together with the accompanying risk factors.

METHODS

Ten thousand individuals selected using the "stratified cluster sampling method" from a total population of 259,428 students within the borders of Kayseri city center constituted the study sample. A questionnaire was prepared in line with the epidemiological studies protocol recommended by the International Epilepsy Union Epidemiology and Prognosis Committee in 1993. Data were analyzed on IBM SPSS Statistics 20. Significance was set at p<0.05.

RESULTS

Of the 15,000 questionnaires distributed, 72% (n=10,742) were returned fully completed. Eighty-three students had been or were still being monitored with a diagnosis of epilepsy. The raw prevalence of epilepsy was 6/1000 in females, 9/1000 in males and 8/1000 in both groups together. Prevalence of active epilepsy was 4/1000 in females, 7/1000 in males and 6/1000 in both groups together. Premature birth increased the risk of epilepsy 2.6 times, and average and poor family income levels increased the risk of epilepsy 3.3 and 1.6 times, respectively. A history of febrile convulsion increased the risk of epilepsy 15.1 times.

CONCLUSION

The prevalence of epilepsy in the 7-17 age group in Kayseri is closer to that in developed rather than developing countries. We conclude that the risk factors for epilepsy, and particularly febrile convulsion, and the true prevalence rates need to be determined through studies involving wide socioeconomic strata.

Prevalence and clinical characteristics of active epilepsy in southern Han Chinese

PURPOSE

To investigate the prevalence and clinical characteristics of active epilepsy in southern Han Chinese.

METHOD

A door-to-door survey about epilepsy was conducted in communities identified by random cluster sampling among 20 villages and 3 communities of Yueyang city. A questionnaire for epilepsy based on the World Health Organization screening questionnaire was used. A final diagnosis of epilepsy was made by neurology specialists with the support of head magnetic resonance imaging (MRI), computed tomography (CT), and electroencephalography (EEG) if available. The prevalence, clinical characteristics, and treatment gap were analyzed in patients with active epilepsy within the past year and the past 5 years.

RESULTS

Active epilepsy was identified in 91 patients within the past year and 117 patients within the past 5 years. The one-year prevalence was 2.8‰, and the five-year prevalence was 3.7‰. The prevalence for epilepsy active within the last year and the last five years was significantly higher in rural areas than in urban areas (P<0.05). Secondary generalized tonic-clonic seizures (53.8%) were the most common seizure type in patients whose epilepsy had been active in the last year. 34.1% of patients were diagnosed with structural or metabolic epilepsy. The most common cause for epilepsy was cerebrovascular disease (32.3%), followed by traumatic brain injury (29.0%). The treatment gap was 93.4%.

CONCLUSION

The prevalence of epilepsy active within the last one and five years was higher in rural areas than in urban areas of Yueyang city. A large treatment gap exists in this area and a rational intervention strategy is needed.

Risk Factors of Early Seizure Recurrence in Epileptic Patients Presented to an Emergency Department in Hong Kong

Introduction

While epilepsy is a well-known disease, little is known about early recurrence of seizures, and some patients are admitted to medical ward for the risk of recurrence of epilepsy. The aim of this study was to determine the frequency and risk factors of early seizure recurrence (ESR) among the epileptic adult patients attending the emergency department (ED).

Methods

In this retrospective observational study, medical records of all patients presenting to a regional ED in Hong Kong with seizures from 1 January 2010 to 31 December 2011 were reviewed. Their demographic data and clinical features were analysed to look for the relationship with ESR. ESR was defined as a seizure recurrence during the first 24 hours since the last seizure.

Results

A total of 339 patient records were analysed. The ESR rate was 13.7% at 24 hours and 80% occurred in the first six hours after the last seizure. Age≥40, female sex, repeated seizure in past one day, and abnormal plasma sodium and calcium levels were found to be statistically significantly associated with ESR by univariate analysis. These risk factors remain statistically significant after repeated multivariate logistic regression analysis.

Conclusion

The ESR rate is about 13.7% in our emergency department setting and 80% of them occur within six hour since their last seizure. Five risk factors, namely age group, sex, repeated seizure in past one day and abnormal blood sodium and calcium level are significant factors associated with ESR. We conclude that it is not necessary to admit all the adult epileptic patients with simple breakthrough seizures to hospital. (Hong Kong j.emerg.med. 2014;21:37-43)

Personality traits and social behaviors predict the psychological adjustment of Chinese people with epilepsy

Very little is known about the psychosocial correlates of psychological morbidity among Chinese people with epilepsy (PWE). No studies have investigated the association between social relationships and psychological morbidity, while most studies examined only the negative impact of maladaptive personalities on psychological adjustment in PWE. This study examined the association of psychological morbidity with a broad array of personality traits and social skills in a sample of 54 Chinese PWE. Respondents completed the Temperament and Character Inventory (TCI), the Social Performance Survey Schedule (SPSS), and the Hospital Anxiety and Depression Scale (HADS) via semi-structured interview. Regression analyses revealed that, independent of demographic and medical variables and perceived impact, Harm Avoidance was positively associated with anxiety and depression whereas Self-Directedness was negatively associated with anxiety and depression; that Cooperativeness was inversely associated with anxiety. Social skills were inversely associated with depression whereas negative social skills were inversely associated with anxiety. Clinical implications of adaptive personality traits and social skills functioning are discussed.

An association analysis of reelin gene (RELN) polymorphisms with childhood epilepsy in eastern Indian population from West Bengal

Epilepsy is a common neurological condition characterized by unprovoked seizure attacks. Early brain developmental abnormalities involving neuronal migration and lamination are implicated in childhood epilepsy. Reelin, a neuronal-signaling molecule plays a crucial role in these migratory processes. Therefore, reelin gene (RELN), which is located on human chromosome 7q22 is considered as a potential candidate gene for childhood epilepsy. In this study, we recruited 63 patients with childhood-onset epilepsy and 103 healthy controls from West Bengal in India. Genomic DNA isolated from leukocytes of cases and control individuals were used for genotyping analysis of 16 markers of RELN. Case-control analysis revealed significant over-representation of G/C and (G/C+C/C) genotypes, and C allele of exon 22 G/C marker (rs362691) in cases as compared to controls. Pair-wise linkage disequilibrium analysis demonstrated two separate LD blocks with moderately high D' values in epileptic cases. Based on these data, we have carried out haplotype case-control analysis. Even though we found over-representation of A-C haplotype of intron 12 A/C/exon 22 G/C markers and haplotype combination involving G-allele of exon 22 marker in cases and controls, respectively, the overall test was not significant. LD in this region involving this marker was also more robust in epileptic cases. Taken together, the results provide possible evidences for association of exon 22 G/C marker or any marker in the vicinity, which is in LD with this marker with epilepsy in the West Bengal population. Further investigations involving higher sample sizes are warranted to validate the present finding.

Prevalence of Epilepsy in a Rural District of Central Lao PDR

PURPOSE

To assess the prevalence of epilepsy in a rural district of Lao PDR and to describe the clinical and epidemiological profile of the disease.

METHODS

Door-to-door screening was performed on the entire population of 8 randomly selected villages in the Hinheub district, using an internationally validated and standardized questionnaire. Additional passive case detection was performed through village key informants. Suspected epilepsy patients identified by the questionnaire were revisited and examined by an experienced neurologist on two follow-up visits. The confirmation of epilepsy was based only on an in-depth clinical examination. Electroencephalograms were performed at the district health care center.

RESULTS

In the 8 villages, 277 suspected cases of epilepsy were identified among 4,310 interviewed subjects; 194 of whom (70%) underwent a clinical examination by a neurologist during the first visit while 65 of 83 remaining suspected cases were seen on the second confirmation visit. Twenty-seven persons with epilepsy were identified. Six additional patients were diagnosed in 219 self-referred subjects. An overall prevalence of 7.7 cases of epilepsy per thousand inhabitants was calculated (95% CI 5.3-10.7). Generalized epilepsy (21 cases, 63.6%) was commoner than partial epilepsy (9 cases, 27.3%). The remaining 3 cases (9.1%) were not-classifiable as either generalized or partial. EEG abnormal findings were found in 12 of the 24 patients (50.0%) who had an EEG registration.

CONCLUSIONS

This is the first study in Lao PDR to estimate the prevalence of epilepsy. Compared to Western countries it shows a pattern towards a higher prevalence.