Full Compensation of Seizures as the Main Goal of Epilepsy Therapy: Will Patients Achieve It More Easily Than 20 Years Ago?

Evaluating Quality of Life in Patients with Epilepsy

Epilepsy is a condition that significantly reduces the quality of life of patients. Reducing the number of seizures is always a good result of therapy, but the ultimate goal of treatment is to achieve a seizure-free state. According to clinical studies, there is a significant relationship between the quality of life of patients and the level of seizure control. A Canadian cross-sectional study evaluated the intrusiveness of the disease and quality of life (QoL) in patients with epilepsy with varying degrees of seizure control. According to the results, intrusiveness changed significantly and inversely proportional to the increasing level of control. Fully compensated disease was associated with the lowest levels of intrusiveness, increased confidence, and QoL.

Another study showed that health-related quality of life (HRQoL) varied significantly among patients with similar seizure frequency, suggesting variability in their subjective perception despite objectively assessed comparable seizure frequency. Only a seizure-free state led to a significantly higher HRQoL.

Findings from a Longitudinal Study

The results of the first part of a longitudinal study from 2000 showed that more than 1/3 of adult patients with epilepsy do not achieve sufficient seizure control when treated with antiepileptics (ASM − antiseizure medication, i.e., antiseizure medication). The authors subsequently expanded the cohort of patients and continued data collection to determine whether the overall outcomes of epilepsy treatment have changed with the development of new ASMs.

The longitudinal cohort study followed patients with newly diagnosed epilepsy who started ASM treatment between 1982 and 2012 at a hospital in Glasgow, Scotland. A total of 1795 patients were included in the analysis. All were followed for at least 2 years or until death. The level of seizure compensation was assessed at the end of the study.

At the last control, a total of 1144 patients (63.7%) were seizure-free for the previous year or longer. 993 (86.8%) patients, who were seizure-free for at least 1 year, were on ASM monotherapy, and in 1028 (89.9%) control of the disease was achieved with the first or second therapeutic regimen.

Of the total number, 906 (50.5%) patients were fully compensated for 1 year or longer with the first ASM used. If the first-choice ASM failed, the 2nd and 3rd therapy regimens were associated with an 11.6% and 4.4% probability of achieving a seizure-free state, respectively. Only 2.1% of patients achieved optimal seizure control with additional ASMs. Epilepsy that was not successfully compensated with the first ASM was 1.73 times more likely to be therapy-resistant with each subsequent treatment regimen.

Summary and Discussion

Achieving full seizure compensation significantly improves the quality of life of patients with epilepsy and represents the primary goal of treatment. Over the past 20 years, however, the overall success rate of ASM therapy has not improved − compared to data from 2000, the proportion of fully compensated patients has not fundamentally changed. According to the results of the longitudinal study, 63.7% of newly diagnosed patients achieve full seizure control for 1 year or longer, the vast majority of them (86.8%) achieve it with ASM monotherapy. More than 1/3 of patients remain insufficiently compensated for epilepsy. The probability of achieving a seizure-free state significantly decreases with each additional tried ASM therapy regimen, and patients also suffer from treatment side effects.

The success rate of therapy in newly diagnosed epilepsy has not improved despite the availability of many new antiepileptics with different mechanisms of action. Therefore, it is essential to develop new disease-modifying drugs that can halt the development or progression of epilepsy.

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Sources:
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