Patterns of treatment response in newly diagnosed epilepsy

Abstract

Objective: To delineate the temporal patterns of outcome and to determine the probability of seizure freedom with successive antiepileptic drug regimens in newly diagnosed epilepsy.Methods: Patients in whom epilepsy was diagnosed and the first antiepileptic drug prescribed between July 1, 1982, and April 1, 2006, were followed up until March 31, 2008. Outcomes were categorized into 4 patterns: A) early and sustained seizure freedom; B) delayed but sustained seizure freedom; C) fluctuation between periods of seizure freedom and relapse; and D) seizure freedom never attained. Probability of seizure freedom with successive drug regimens was compared. Seizure freedom was defined as no seizures for Ն1 year.Results: A total of 1,098 patients were included (median age 32 years, range 9-93). At the last clinic visit, 749 (68%) patients were seizure-free, 678 (62%) on monotherapy. Outcome pattern A was observed in 408 (37%), pattern B in 246 (22%), pattern C in 172 (16%), and pattern D in 272 (25%) patients. There was a higher probability of seizure freedom in patients receiving 1 compared to 2 drug regimens, and 2 compared to 3 regimens (p Ͻ 0.001). The difference was greater among patients with symptomatic or cryptogenic than with idiopathic epilepsy. Less than 2% of patients became seizure-free on subsequent regimens but a few did so on their sixth or seventh regimen. Conclusions:Most patients with newly diagnosed epilepsy had a constant course which could usually be predicted early. The chance of seizure freedom declined with successive drug regimens, most markedly from the first to the third and among patients with localization-related epilepsies. Neurology Seventy million people have epilepsy, with 34 -76 per 100,000 developing the condition every year.1 To formulate rational treatment plans, it is important to understand the different clinical courses and patterns of response to antiepileptic drugs (AEDs), ideally by following outcomes from the point of treatment initiation. Most studies conducted at specialist centers were limited by selection bias toward patients with chronic refractory epilepsy.2-5 The few reported cohorts of newly diagnosed patients tended to include only children 6,7 or focus on response over time irrespective of treatment status. 8 We have previously reported outcomes in adolescent and adult patients with newly diagnosed epilepsy.9,10 Over the ensuing years many new AEDs have become available, but their impact on the overall prognosis of epilepsy remains unclear. The main objectives of the present analysis were to delineate the temporal patterns of seizure outcome and to determine the probability of seizure freedom with successive regimens in an expanded cohort of 1,098 newly diagnosed patients, who were recruited between 1982 and 2006 and followed for up to 26 years. Most were referred by their primary care physicians with less than 10% by the hospital's accident and emergency department. The study population included the patients analyzed in our previous reports (n ϭ 470 and 890, ...

Patterns of seizure control in patients with mesial temporal lobe epilepsy with and without hippocampus sclerosis

“…Even those with current seizure remission tried more than two drugs before a later seizure control. However, it is known that epilepsies are dynamic diseases and the response to AEDs may vary throughout life without any external interference, possibly due to fluctuations inherent to its pathophysiology 3 .…”

“…Although the majority of patients will have a stable pattern of response to the medications through long-term follow-ups, an intermittent pattern with refractory seizures interrupted by periods of remission can occur 2 . It has been estimated that around 16% of patients with epilepsies will have a relapse-remitting course, intercalating periods of seizure remission and refractory seizures 3 . It is also current knowledge that the underlying cause of the epilepsy is the major contributor to define AED response 4 .…”

2015 ACVIM Small Animal Consensus Statement on Seizure Management in Dogs

“…Overwhelming evidence exists in people that there is no benefit to starting treatment after a single unprovoked event 14. The earlier AED treatment is started; however, the better the potential outcome may be for seizure control 21, 22, 23. Recurrent epileptic seizures can increase epileptogenesis and drug resistance in a subgroup of patients 24, 25.…”

Genetic Biomarkers in Epilepsy

“…As epilepsy is a chronic disease, many patients receive life-long antiepileptic medication. AED therapy is very effective as 60-70 % of patients become seizurefree with the first or second AED tried [86,87], but side effects are common. More than a third of patients develop specific side effects on AEDs, but we are not able to predict who will suffer from which side effect in which dosage.…”