Establishing the cross‐cultural applicability of a harmonized approach to cognitive diagnostics in epilepsy: Initial results of the International Classification of Cognitive Disorders in Epilepsy in a Spanish‐speaking sample

Abstract

Objective This study was undertaken to evaluate the cross‐cultural application of the International Classification of Cognitive Disorders in Epilepsy (IC‐CoDE) to a cohort of Spanish‐speaking patients with temporal lobe epilepsy (TLE) living in the United States. Methods Eighty‐four Spanish‐speaking patients with TLE completed neuropsychological measures of memory, language, executive function, visuospatial functioning, and attention/processing speed as part of the Neuropsychological Screening Battery for Hispanics. The contribution of demographic and clinical variables to cognitive performance was evaluated. A sensitivity analysis was conducted by examining the base rates of impairment across several impairment thresholds. The IC‐CoDE taxonomy was then applied, and the base rate of cognitive phenotypes for each cutoff was calculated. The distribution of phenotypes was compared to the published IC‐CoDE taxonomy data, which utilized a large, multicenter cohort of English‐speaking patients with TLE. Results Across the different impairment cutoffs, memory was the most impaired cognitive domain, with impairments in list learning ranging from 50% to 78%. Application of the IC‐CoDE taxonomy utilizing a −1.5‐SD cutoff revealed an intact cognitive profile in 47.6% of patients, single‐domain impairment in 23.8% of patients, bidomain impairment in 14.3% of patients, and generalized impairment in 14.3% of the sample. This distribution was comparable to the phenotype distribution observed in the IC‐CoDE validation sample. Significance We demonstrate a similar pattern and distribution of cognitive phenotypes in a Spanish‐speaking epilepsy cohort compared to an English‐speaking sample. This suggests stability in the underlying phenotypes associated with TLE and applicability of the IC‐CoDE for guiding cognitive diagnostics in epilepsy research that can be applied to culturally and linguistically diverse samples.

Cortical Thickness Patterns of Cognitive Impairment Phenotypes in Drug‐Resistant Temporal Lobe Epilepsy

“…Our study presents one of the first expertly curated German cohorts with cognitive phenotyping that underwent a broad battery of neuropsychological tests spanning 5 cognitive domains. Cognitive phenotyping has previously been established in a large American English‐speaking cohort, 4 and recently validated in an American Spanish‐speaking cohort 37 . Our study shows broader applicability of the IC‐CoDE criteria approach and thus aids in the undertaking to standardize cognitive research across countries and languages.…”

“…Cognitive phenotyping has previously been established in a large American Englishspeaking cohort, 4 and recently validated in an American Spanish-speaking cohort. 37 Our study shows broader applicability of the IC-CoDE criteria approach and thus aids in the undertaking to standardize cognitive research across countries and languages. In our cohort, the largest group of patients was categorized into the MDI (53.2%), followed by FI (29.8%), and finally MI (16.9%) cognitive groups.…”

Cognitive phenotypes in late-onset epilepsy: results from the atherosclerosis risk in communities study

“…In fact, in a sample of 1,409 young-tomiddle aged adults with temporal lobe epilepsy, 49% of the patients with a Single Domain phenotype had isolated deficits in language (53). In a sample of Spanish-speaking patients with temporal lobe epilepsy, memory was the most commonly impaired domain within the Single Domain phenotype (55). The differences in the nature of the Single Domain phenotype across studies may be due to varying underlying epilepsy etiologies, epilepsy-related clinical factors, sociodemographic characteristics, or differences in brain abnormalities (e.g., lateral versus mesial temporal lobe involvement).…”

“…Our group has shown that in young-to-middle aged adults, the phenotyping approach better captures the heterogeneity inherent both within and across epilepsy syndromes compared to analyzing individual scores in isolation (40, [49][50][51][52][53][54][55]. We have demonstrated that cognitive phenotypes are stable and robust across cohorts and are associated with distinct patterns of brain imaging abnormalities (49,51,56,57).…”

The relationship between mood and anxiety and cognitive phenotypes in adults with pharmacoresistant temporal lobe epilepsy

“…5 Of interest, a recent large-scale, multicenter study demonstrated significant heterogeneity in IC-CoDE phenotypes in adults with TLE (i.e., 50% intact, 26% single-domain, 14% bi-domain, 10% generalized), 5 which has since been replicated in independent cohorts. 12,13 Although it remains unclear what combination of factors account for the variability in cognitive phenotypes in adults with TLE, the initial IC-CoDE proposal suggested several potential modifiers as part of the new taxonomy (i.e., extent of impairment, etiology, mood), which have yet to be studied in clinical samples. 5 The goal of the current study was to investigate the relationship between psychiatric comorbidities and IC-CoDE phenotypes in a large cohort of adults with TLE.…”