Racial disparities in temporal lobe epilepsy

Disparities in Epilepsy Diagnosis and Management in High-Income Countries: A Review of the Literature

Purpose of Review

Currently, an estimated 3.4 million people in the United States live with epilepsy. Previous studies have identified health disparities associated with race/ethnicity, socioeconomic status (SES), sex, insurance status, and age in this population. However, there has been a dearth of research addressing these disparities. We performed a literature review of articles published between 2010 and 2020 pertaining to health disparities in people with epilepsy (PWE), identified key factors that contribute to gaps in their care, and discussed possible solutions.

Recent Findings

Health disparities in prevalence, treatment access, time to diagnosis, health care delivery and engagement, and clinical outcomes were identified among individuals who were either of low SES, rural-based, uninsured/underinsured, older patients, patients of color, or female sex.

Summary

Disparities in care for PWE continue to persist. Greater priority should be placed on addressing these gaps intricately tied to sociodemographic factors. Reforms to mitigate health disparities in PWE are necessary for timely diagnosis, effective treatment, and positive long-term outcomes.

Inequities in therapy for infantile spasms: a call to action

OBJECTIVE

To determine whether selection of treatment for children with infantile spasms (IS) varies by race/ethnicity.

METHODS

The prospective US National Infantile Spasms Consortium database includes children with IS treated from 2012-2018. We examined the relationship between race/ethnicity and receipt of standard IS therapy (prednisolone, adrenocorticotropic hormone, vigabatrin), adjusting for demographic and clinical variables using logistic regression. Our primary outcome was treatment course, which considered therapy prescribed for the first and, when needed, the second IS treatment together.

RESULTS

Of 555 children, 324 (58%) were Non-Hispanic white, 55 (10%) Non-Hispanic Black, 24 (4%) Non-Hispanic Asian, 80 (14%) Hispanic, and 72 (13%) Other/Unknown. Most (398, 72%) received a standard treatment course. Insurance type, geographic location, history of prematurity, prior seizures, developmental delay or regression, abnormal head circumference, hypsarrhythmia, and IS etiologies were associated with standard therapy. In adjusted models, Non-Hispanic Black children had lower odds of receiving a standard treatment course compared with Non-Hispanic white children (OR 0.42, 95% CI 0.20-0.89, p = 0.02). Adjusted models also showed that children with public (vs. private) insurance had lower odds of receiving standard therapy for treatment 1 (OR 0.42, CI 0.21-0.84, p = 0.01).

INTERPRETATION

Non-Hispanic Black children were more often treated with non-standard IS therapies than Non-Hispanic white children. Likewise, children with public (vs. private) insurance were less likely to receive standard therapies. Investigating drivers of inequities, and understanding the impact of racism on treatment decisions, are critical next steps to improve care for patients with IS. This article is protected by copyright. All rights reserved.

Epilepsy, dissociative seizures, and mixed: Associations with time to video-EEG

PURPOSE

Video-electroencephalographic monitoring (VEM) is a core component to the diagnosis and evaluation of epilepsy and dissociative seizures (DS)-also known as functional or psychogenic seizures-but VEM evaluation often occurs later than recommended. To understand why delays occur, we compared how patient-reported clinical factors were associated with time from first seizure to VEM (TVEM) in patients with epilepsy, DS or mixed.

METHODS

We acquired data from 1245 consecutive patients with epilepsy, VEM-documented DS or mixed epilepsy and DS. We used multivariate log-normal regression with recursive feature elimination (RFE) to evaluate which of 76 clinical factors interacting with patients' diagnoses were associated with TVEM.

RESULTS

The mean and median TVEM were 14.6 years and 10 years, respectively (IQR 3-23 years). In the multivariate RFE model, the factors associated with longer TVEM in all patients included unemployment and not student status, more antiseizure medications (current and past), concussion, and ictal behavior suggestive of temporal lobe epilepsy. Average TVEM was shorter for DS than epilepsy, particularly for patients with depression, anxiety, migraines, and eye closure. Average TVEM was longer specifically for patients with DS taking more medications, more seizure types, non-metastatic cancer, and with other psychiatric comorbidities.

CONCLUSIONS

In all patients with seizures, trials of numerous antiseizure medications, unemployment and non-student status was associated with longer TVEM. These associations highlight a disconnect between International League Against Epilepsy practice parameters and observed referral patterns in epilepsy. In patients with dissociative seizures, some but not all factors classically associated with DS reduced TVEM.

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.

Racial differences in adult-onset MRI-negative temporal lobe epilepsy

OBJECTIVE

We recently detected a significant racial difference in our population with temporal lobe epilepsy (TLE) at the University of Alabama at Birmingham (UAB) seizure monitoring unit. We found that Black patients were more likely than their White counterparts to carry a TLE diagnosis. Using this same patient population, we focus on the patients with TLE to better describe the relationship between race and epidemiology in this population.

METHODS

We analyzed the data from patients diagnosed with TLE admitted to the UAB seizure monitoring unit between January 2000 and December 2011. For patients with a video electroencephalography (EEG) confirmed diagnosis of TLE (n = 385), basic demographic information including race and magnetic resonance imaging (MRI) findings were collected. Descriptive statistics and multivariate logistic regression were used to explore the relationship between MRI findings, demographic data, and race.

RESULTS

For Black patients with TLE, we found that they were more likely to be female (odds ratio [OR] = 1.91, 95% confidence interval [CI]: 1.14-3.19), have seizure onset in adulthood (OR = 2.39, 95% CI: 1.43-3.19), and have normal MRIs (OR = 1.69, 95% CI: 1.04-2.77) compared to White counterparts with TLE after adjusting for covariates.

CONCLUSIONS

These data suggest that Black race (compared to White) is associated with higher expression of adult-onset MRI-negative TLE, an important subtype of epilepsy with unique implications for evaluation, treatment, and prognosis. If validated in other cohorts, the findings may explain the lower reported rates of epilepsy surgery utilization among Blacks. The racial differences in surgical utilization could be due to a greater prevalence of an epilepsy that is less amenable to surgical resection rather than to cultural differences or access to care.

Presentation of psychogenic nonepileptic seizures in Hawaii's ethnoracially diverse population

PURPOSE

This exploratory study compared the semiology of psychogenic nonepileptic seizures (PNES) between a diverse group of patients in the state of Hawaii. This study may expand understanding of PNES across different ethnocultural and gender groups.

METHODS

A retrospective chart review of patients admitted to our Epilepsy Monitoring Unit (EMU) over a 4-year period was performed to compare semiology in different ethnic groups and gender.

RESULTS

A total of 139 patients were included in this study, 37% (n = 51) with PNES, 34% (n = 47) with epilepsy only, and 29% (n = 41) with other non-PNES, nonepilepsy diagnosis. The number of Asians with PNES were found to differ when compared with the patients with epilepsy and the patients with non-PNES, nonepilepsy diagnosis. A positive trend was found in the number of Native Hawaiians and Caucasians with PNES in comparison with patients with non-PNES, nonepilepsy diagnosis. In addition, three semiology of PNES in Native Hawaiians were found to differ in comparison with other ethnic groups with PNES: rhythmic motor, mixed semiology, and nonepileptic aura. There is a significant difference in all motor manifestation between males and females in Native Hawaiians. Between patients with PNES, patients with epilepsy, and patients with non-PNES, nonepilepsy diagnosis, significant correlation was found in psychiatric disorders including posttraumatic stress disorder (PTSD), anxiety, and any psychiatric disorder.

CONCLUSION

This cross-cultural study found significant differences in the expression of PNES across key ethnoracial groups for the Islands of Hawaii. These findings have implications to the diagnosis and treatment of PNES for Native Hawaiians and other Pacific Islanders in the United States.