Long term effects of refractory temporal lobe epilepsy on cognitive abilities: a cross sectional study

Abstract

Objective-Intractable epilepsy is related to various transient and chronic brain electric and neurochemical disturbances. There is increasing evidence that chronic epilepsy induces secondary neuronal metabolic and structural decline. However, there is no convincing evidence that the cognitive abilities of patients deteriorate with increasing duration of intractable epilepsy. A second ANOVA including education as factor showed that in patients with higher educational attainment, the mean FSIQ was stable for a longer duration of TLE than in less educated patients. Retesting 6 months after anterior temporal lobectomy seizure free patients (n=85 of 127) had an higher FSIQ but showed a similar duration eVect before and after anterior temporal lobectomy. The variables age at epilepsy onset, education, frequency of interictal epileptiform discharges, frequency of habitual and generalised seizures, serum concentration of antiepileptic drugs, and polypharmacy were statistically controlled. Conclusions-Psychometric intelligence of patients with a longer duration of refractory TLE were most severely impaired. Consequently, refractory TLE seems to be associated with slow but ongoing cognitive deterioration. It is assumed that epilepsy related noxious events and agents exhaust the compensatory capacity of brain functions. However, as in dementia and Alzheimer's disease, higher educational attainment as an indicator of higher brain reserve might delay the cognitive decline. (J Neurol Neurosurg Psychiatry 1999;67:44-50) Methods-To

Gender‐specific Differences of Hypometabolism in mTLE: Implication for Cognitive Impairments

“…Although this was observed in the majority of cases, it is not the only possible route of spread. The functional and structural changes in the mesial temporal regions correlate with seizure frequency (33,36,37). The most likely explanation for the reduced metabolism in remote brain areas is a functional inhibition of the remote regions by ongoing, subclinical epileptic activity in the epileptogenic mesial temporal lobe (9).…”

Is Refractory Epilepsy Preventable?

“…However, it is less clear that surgery could improve the neuropsychological or psychiatric morbidity associated with refractory epilepsy (77,78). For example, adults are at risk of verbal memory impairment after removal of the dominant temporal lobe (78,79).…”

Cognitive Impairment in Epilepsy: A Clinical Study

“…The present investigators studied exclusively a group of patients with GTCS not associated with brain damage or other factors which could produce cognitive impairment. The other investigators explained that the cognitive impairment could be attributed to brain damage, age of onset of epilepsy, nature and location of seizure focus, duration of epilepsy, anticonvulsant drugs and epilepsy related surgery 5,6,7,8 Few earlier studies reported that there is significant cognitive impairment in patients with idiopathic GTCS without brain damage. 10,11 The cognitive impairment could be due to subtle brain damage which the present investigators could not exclude with neurological and neuropsychological investigations.…”

“…4 Several variables have been implicated in the development of cognitive deficits, including age at onset, nature of seizures, location of seizure foci, duration of seizure free period, use of antiepileptic drugs and epilepsy related surgery. 5,6,7,8 Other studies have focused on cognitive performance at disease onset and found that individuals with epilepsy performed worse than siblings or normal controls on several neuropsychological tests. 9,10,11,12 The domains of cognition most often affected include attention and concentration, language, memory, intelligence, executive functions, motor speed and visuo-spatial processing speed.…”

“…47,50,51 Patients with idiopathic generalized epilepsy, early seizure onset prior to 18 years was a powerful predictor of neuropsychological impairment. 7,8,52 There are several reports about the cognitive impairment and cognitive deterioration in patients with epilepsy.The research data indicate that the cognitive impairment and deterioration are due to associated brain damage and not attributable to Epilepsy. There are only a limited number of studies investigating the cognitive impairment in uncomplicated epilepsy, with good seizure control and without obvious structural brain damage.Aims of the study wereto evaluate the frequency and nature of the cognitive impairment in patients with epilepsy and to evaluate the relationship between sociodemographic and clinical variables and cognitive impairment in patients with epilepsy.…”