Can epilepsy affect normal EEG variants? A comparative study between subjects with and without epilepsy.

OBJECTIVES: To compare the prevalence of benign EEG variants (BEVs) between epileptic and non-epileptic subjects. METHODS: A prospective, observational EEG study of 1,163 consecutive patients, using the 10-20 international system with systematically two additional anterior/inferior temporal electrodes. The video-EEG monitoring duration was between 24 h and eight days. RESULTS: We identified 917 (78.9%) epileptic patients (mean age: 33.42 ± 15.5 years; females: 53.4%) and 246 (21.2%) non-epileptic patients (mean age: 35.6 ± 18.75 years; females: 54.9%). Despite a shorter mean duration of the EEG recordings, the prevalence of BEVs was higher in non-epileptic vs. epileptic patients (73.2% vs. 57.8%, p = 0.000011). This statistical difference was confirmed for lambda waves (23.6% in the non-epilepsy group vs. 14.8% in the epilepsy group, p = 0.001), POSTs (50.8% vs. 32.5%, p < 0.000001), wicket spikes (20.3% vs. 13.6%, p = 0.009) in particular in NREM and REM sleep, and 14- and 6-Hz positive bursts (13% vs. 7.1% p = 0.003). Mu rhythm was observed at the same frequency in both groups (21.1% in the non-epilepsy group vs. 22.7% in the epilepsy group). There was no difference between the two groups for rarer rhythms, such as rhythmic mid-temporal theta burst of drowsiness, small sharp spikes, and midline theta rhythm. CONCLUSIONS: There was no increase in any of the BEVs in the epilepsy group. On the contrary, BEVs were more frequent and diversified in the non-epilepsy group. Epilepsy may negatively affect the occurrence of the most common BEVs, with the exception of the mu rhythm, which is present in about one-fifth of the population with or without epilepsy.

Benign EEG variants in the sleep-wake cycle: A prospective observational study using the 10-20 system and additional electrodes.

OBJECTIVES: To study the prevalence of benign EEG variants (BEVs) in the sleep-wake cycle among 1163 consecutive patients. METHODS: Prospective, observational EEG study using the 10-20 system with systematically two additional anterior-temporal electrodes. Depending on clinical indications, other electrodes were added. REM sleep identification was based on its characteristic EEG grapho-elements and rapid eye movements, clearly detectable with the additional anterior-temporal and fronto-polar electrodes due to eye proximity. The video-EEG monitoring duration was between 24hours and eight days. RESULTS: We identified 710 patients (61%) with BEVs. Positive occipital sharp transients of sleep (POSTs) were observed in 36.4% of participants, mu rhythm in 22.4%, lambda waves in 16.7%, wicket spikes (WS) in 15%, 14- and 6-Hz positive bursts in 8.3%, benign sporadic sleep spikes (BSSS) in 3.3%, rhythmic mid-temporal theta burst of drowsiness (RMTD) in 2.15%, midline theta rhythm in 2.1% and six-Hz spike and wave (SW) bursts in 0.1%. WS and RMTD were present during wakefulness, NREM (14.1%, 1.3%, respectively) and REM sleep (3.3%, 1.1%, respectively). Mu rhythm was also observed during NREM (1.5%) and REM sleep (7.7%). Fourteen- and 6-Hz positive bursts were present during NREM (4.5%) and REM sleep (6.5%). BSSS and six-Hz SW bursts were only observed during NREM sleep. CONCLUSIONS: The prevalence of BEVs is much higher than current estimates. POSTs and WS can no longer be considered as unusual patterns but physiological patterns of NREM sleep. RMTD and mu rhythm may be observed during NREM and REM sleep.

Open-label, uncontrolled retrospective study of perampanel in adults with Lennox-Gastaut syndrome.

PURPOSE: Perampanel (PER) was added to the anticonvulsant regimen of 71 patients with Lennox-Gastaut Syndrome (LGS) to evaluate its efficacy against seizures and its tolerability. METHOD: We evaluated at 3-month intervals 62 with pure LGS and 9 with LGS-like epileptic encephalopathy (28 females, 43 males, mean age 40.1 ± 11.5 yrs, median 38, range 20-71) in whom PER was introduced by 2 mg steps at 2- to 4-week intervals up to 6 mg/day, with possible dose reduction or increases after that. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines were followed. RESULTS: Mean PER exposure was 538.9 days ± 425 (median 429), with 44 patients (62 %) on PER at last follow-up. About 2/3 of patients were responders, including 35.2 % that had a ≥75 % decrease in their seizures. Among these 16.9 % had a ≥90 % decrease. No improvement was seen in 14 patients; 5 had a less than 50 % response, and 6 had seizure aggravation. Therefore, 25 (35.2 %) were considered non-responders. Half of the patients developed at least one side-effect. Significant negative changes in behavior were noted in 1/3 of the cases, including irritability (8.5 %) and aggressivity (7 %). Contrastingly, 4 patients reported positive behavioral and psychological well-being side-effects. CONCLUSIONS: This retrospective, open-label study provides evidence that PER may significantly help in LGS. PER should be tried in LGS patients who are not satisfactorily controlled. Its use may be limited in some patients due to behavioral side-effects occurring, particularly at doses ≥ 6 mg/d.

Perampanel in 12 patients with Unverricht-Lundborg disease.

OBJECTIVE: Perampanel (PER) was used in 12 patients with Unverricht-Lundborg disease (ULD) to evaluate its efficacy against myoclonus and seizures. METHODS: We treated 11 patients with EPM1 mutations (6 F, 5 M, aged 13-62 years) and a 43-year-old man with de novo KCNC1 mutation. PER was introduced by 2 mg steps at 2-4 week intervals until 6 mg/day, with a possible dose reduction or dose increase. RESULTS: Ten patients had a clear clinical response of myoclonus, and five were able to reduce concomitant therapy. Improvement was noted sometimes as soon as with 2 mg/day. Epileptic seizures stopped on PER in the six patients who still had experienced generalized tonic-clonic or myoclonic seizures (100%). Some abatement of efficacy on myoclonus was seen in two patients who still retained some benefit. Weight gain was reported in six patients (50%). Psychological and behavioral side-effects were observed in six patients (50%) and led to withdrawal of PER in three cases and dose reduction in three, with abatement of the problems. SIGNIFICANCE: This study provides evidence that for ULD patients, PER may show marked efficacy even in severe cases, particularly against myoclonus, but also against seizures. PER should thus be tried in ULD patients whose seizures are not satisfactorily controlled. Its use is limited because of psychological and behavioral side effects, with higher doses of approximately 6 mg/day or greater likely risk factors.

Can emotional stress trigger the onset of epilepsy?

OBJECTIVE: The aim of this study was to investigate the potential role of an acute adverse stress as "trigger" for the onset of epilepsy. METHODS: Among 4618 consecutive patients, twenty-two reported a major life event within three months before the onset of epilepsy. RESULTS: All patients had focal epilepsy except one with idiopathic generalized epilepsy. The temporal lobe was involved in 90% of patients with focal epilepsy. More precisely, 13 patients (62% of patients with focal epilepsy) had medial temporal lobe epilepsy (MTLE), two had lateral temporal lobe epilepsy, four had temporoparietooccipital junction epilepsy, and two patients had central lobe epilepsy. The mean age and the median age at onset of epilepsy for patients with MTLE were both 38 years (range: 9.5-65 years). Ten patients had right and three had left MTLE. Among patients with focal epilepsy, MRI was abnormal in 7 (33%) with hippocampal sclerosis in four, periventricular nodular heterotopia in two, and complex cortical dysgenesis in one. The mean age at onset of epilepsy for patients with brain lesions was 26 years (range: 9.5-49). Twelve patients (54%) reported a death as a triggering factor for the onset of their epilepsy. Seven patients (32%) reported that a relationship of trust had been broken. Three patients (14%) had been subjects of violence. No patient reported sexual abuse as a triggering factor. CONCLUSION: This study provides evidence that some patients (5/1000 patients) began their seizures in the wake of significant life events. The average age at onset of epilepsy is quite late, around age 30, even in the presence of brain lesions. These patients are emotionally and affectively more prone to have consequences of a stressful life event. The recognition and management of such situations may bring significant relief with improvement of the control of epilepsy.