Abstracts

Rationale: There are some lines of evidence that epilepsy is a progressive disease and that some factors related to refractoriness along the life of patients with temporal lobe epilepsy (TLE) can be associated with a progressive cognitive decline. Memory and executive dysfunction have been widely reported in children/adolescents and adults with TLE related to hippocampal sclerosis (HS). The aim of the present study was to investigate the impact of having a refractory unilateral TLE-HS in memory and executive functions performance in three age groups and to determine if some subdomains show a decline along the life. Methods: Sixty-one patients with unilateral TLE-HS categorized into three age groups [children/adolescents – from 8 to 17 y/o; young adults – from 18 to 35 y/o; and middle-age adults – from 36 to 64 y/o] were included in this study. Patients were submitted to an age-appropriate neuropsychological evaluation consisting of attentional, memory, executive functions and intelligence tests. Patients’ scores were standardized based on three age-similar control groups (n=65), with no history of psychiatric or neurological disorders. Patients groups were composed of 21 children/adolescents (13 males; with mean age of 11.76 [±2.17] y/o, and mean IQ of 95.52 [±14.42]), 19 young adults (6 males; with mean age of 25.53 [±6.19] y/o, and mean IQ of 90.24 [±10.46]), and 21 middle-age adults (7 males; with mean age of 48.71 [±7.14] y/o, and mean IQ of 93.50 [±14.54]). Z scores of the three age groups were compared with multivariate analysis of variance. Between groups comparisons were carried out with ANOVA and Sidak post-hoc was used when a significant difference was demonstrated in between-group analysis. Results: A significant effect of age range was observed from the multivariate analysis (Pillai's Trace; F=4.14; p < 0.001). Between group comparisons showed significant differences in distinct domains, such as: attention (young adults had higher scores than middle-age adults [p=0.021]), episodic memory (middle-age adults with lower scores than young adults [p=0.077] and children [p=0.063]), semantic memory (children with higher scores than young adults [p=0.099] and middle-age adults [p < 0.001] and young adults with lower scores than middle-age adults [p=0.043]), learning (children with higher scores than young adults [p=0.001] and middle-age adults [p=0.085]), and in executive functions (children showing higher scores than young adults [p=0.002] and middle-age adults [p=0.046]). Conclusions: A more pronounced cognitive impairment was evident as patients with TLE-HS got older. This cognitive profile was not specific to memory functions but comprised attentional and executive functions as well. Our findings support the concept of TLE-HS as a progressive disease and extend previous literature by showing that other cognitive functions suffer from the impact of neurobiological factors related to temporal lobe epilepsy. Funding: Dr. Vincentiis received grants from Foundation for Research Support of the State of São Paulo (FAPESP 13/11361-4). Dr. Rzezak received a grant from Foundation for Research Support of the State of São Paulo (FAPESP 12/09025-3; 12/13065-0). Dr. Valente received grants from the Brazilian Research and Development Council (CNPQ 307262/2011-1) and Foundation for Research Support of the State of São Paulo (FAPESP 13/11361-4; 12/09025-3). Dr. Leite received grants from the Brazilian Research and Development Council (CNPq 476250/2013-7 and 466995/2014).