Quality of life and cognitive function
The severity of seizures is a major determinant of the impact of epilepsy on quality of life. Harden et al used a data set of 118 women from the baseline phase of a clinical treatment trial to evaluate the relationship between seizure severity and aspects of quality of life. Two domains of the Quality of Life in Epilepsy-31 (QOLIE-31) correlated highly significantly with seizure severity: Seizure Worry (r = −0.265, P = .004) and Social Functioning (r = −0.280, P = 0.002). Two additional domains were significantly correlated: Overall Quality of Life (r = −0.210, P = 0.023) and Cognitive (r = −0.209, P = 0.024). When the potentially confounding effect of depression, measured by the Beck Depression Inventory, was controlled for, the regression of seizure severity with QOLIE-31 Seizure Worry remained significant (P = 0.006, R2 = 0.153), as did the regression with QOLIE-31 Social Functioning (P = 0.002, R2 = 0.184) and the regression with QOLIE-31 Cognitive (P = 0.037, R2 = 0.30). These findings indicate that severe and potentially injurious seizure behaviors contribute to anxiety and socially avoidant behavior for persons with intractable epilepsy.
Likewise, Kent et al assessed the relationship between whether duration (time since diagnosis) of refractory epilepsy and progressive memory loss. They studied 250 individuals with left or right temporal lobe epilepsy and those diagnosed with psychogenic nonepileptic seizures. Verbal and nonverbal memory function was assessed using several memory assessment measures administered to all individuals as part of a larger neuropsychological assessment. Multivariate multiple regression analyses demonstrated that duration of temporal lobe epilepsy and age of seizure onset are significantly related to verbal memory deficits in patients with epilepsy. The interaction between duration of epilepsy and diagnostic group was nonsignificant, as was the interaction between age at spell onset and diagnostic group. As measured by several neuropsychological memory tests, duration of disease adversely affects verbal memory performance in patients diagnosed with temporal lobe epilepsy. Their study also supports the notion that age at seizure onset significantly affects verbal memory performance in this population. These results have implications for the strategy of treatment and counseling of patients with intractable temporal lobe epilepsy.
Adapted from Harden et al. The effect of seizure severity on quality of life in epilepsy. Epilepsy Behav 2007;11:208-11; and Kent et al. The effects of duration of intractable epilepsy on memory function. Epilepsy Behav 2006;9:469-77.
Accidents and injuries occur slightly more frequently among people with epilepsy than in the general population, particularly in those with symptomatic epilepsy, frequent seizures, and associated handicaps. The majority of accidents are minor and occur at home. The most frequent injuries among patients with epilepsy are contusions, wounds, fractures, abrasions, and brain concussions. The mortality in population-based studies is two to three times higher for people with epilepsy than in the general population. This is largely related to the etiology of the epilepsy and is probably not influenced by its treatment. On the other hand, most fatalities in patients with chronic, therapy-resistant epilepsy seem to be seizure related and are often sudden unexpected deaths (SUDEP). The frequency of such seizure-related deaths is most likely to be reduced by intensified treatment aimed at early seizure control, although appropriate studies for definitive evidence are still lacking. Apparently, there is an increased rate of traffic accidents in drivers with epilepsy, even if population-based prospective data are lacking. Many of these accidents are seizure related.
Adapted from Elger CE, Schmidt D. Modern management of epilepsy. Epilepsy Behav 2008;12:501-39.