Rod Duncan

A multicenter, randomized clinical study to evaluate the effect on cognitive function of topiramate compared with valproate as add-on therapy to carbamazepine in patients with partial-onset seizures

Summary: Purpose: This study compares the cognitive effects of topiramate (TPM) with those of valproate (VPA) using efficacious doses of each drug when used as adjunctive therapy to carbamazepine (CBZ). A key question of the study is to what extent a more gradual introduction of TPM improves tolerabil‐ity and prevents cognitive impairment.

Minimum requirements for the diagnosis of psychogenic nonepileptic seizures: A staged approach

An international consensus group of clinician‐researchers in epilepsy, neurology, neuropsychology, and neuropsychiatry collaborated with the aim of developing clear guidance on standards for the diagnosis of psychogenic nonepileptic seizures (PNES). Because the gold standard of video electroencephalography (vEEG) is not available worldwide, or for every patient, the group delineated a staged approach to PNES diagnosis. Using a consensus review of the literature, this group evaluated key diagnostic approaches. These included: history, EEG, ambulatory EEG, vEEG/monitoring, neurophysiologic, neurohumoral, neuroimaging, neuropsychological testing, hypnosis, and conversation analysis. Levels of diagnostic certainty were developed including possible, probable, clinically established, and documented diagnosis, based on the availability of history, witnessed event, and investigations, including vEEG. The aim and hope of this report is to provide greater clarity about the process and certainty of the diagnosis of PNES, with the intent to improve the care for people with epilepsy and nonepileptic seizures.

Minimum requirements for the diagnosis of psychogenic nonepileptic seizures: a staged approach: a report from the International League Against Epilepsy Nonepileptic Seizures Task Force.

An international consensus group of clinician‐researchers in epilepsy, neurology, neuropsychology, and neuropsychiatry collaborated with the aim of developing clear guidance on standards for the diagnosis of psychogenic nonepileptic seizures (PNES). Because the gold standard of video electroencephalography (vEEG) is not available worldwide, or for every patient, the group delineated a staged approach to PNES diagnosis. Using a consensus review of the literature, this group evaluated key diagnostic approaches. These included: history, EEG, ambulatory EEG, vEEG/monitoring, neurophysiologic, neurohumoral, neuroimaging, neuropsychological testing, hypnosis, and conversation analysis. Levels of diagnostic certainty were developed including possible, probable, clinically established, and documented diagnosis, based on the availability of history, witnessed event, and investigations, including vEEG. The aim and hope of this report is to provide greater clarity about the process and certainty of the diagnosis of PNES, with the intent to improve the care for people with epilepsy and nonepileptic seizures.

Ictal/postictal SPECT in the pre-surgical localisation of complex partial seizures.

Single photon emission computed tomography (SPECT) used in conjunction with HM-PAO (Ceretec-Amersham International) was used to image regional cerebral blood flow (rCBF) in 28 patients with medically intractable complex partial seizures during or soon after a seizure, and interictally. Changes from interictal rCBF were seen in 26/28 (93%) patients. The main findings were; 1) During the seizure--hyperperfusion of the whole temporal lobe; 2) Up to 2m postically--hyperperfusion of the hippocampus with hypoperfusion of lateral temporal structures; 3) From 2-15m postically--hypoperfusion of the whole temporal lobe. When compared with EEG and MRI data, correct localisation to one temporal lobe was obtained in 23 patients. In one further patient bilateral temporal foci, and in a further two patients frontal foci, were correctly identified. There were no disagreements between EEG and SPECT localisation. Temporal lobe surgery was successful (by the criterion of at least 90% reduction in seizure frequency) in all but one of the 23 patients operated on. It is concluded that ictal/postictal SPECT is a reliable technique for the presurgical localisation of complex partial seizures. The data indicate a likely sequence of changes in rCBF during and after complex partial seizures of temporal lobe origin.

Early outcomes and predictors in 260 patients with psychogenic nonepileptic attacks

Objective: To determine short-term outcome and its predictors in patients with psychogenic nonepileptic attacks (PNEA). Methods: Retrospective cohort study of outcomes relating to attendance at follow-up, spells, use of emergency services, employment, and social security payments recorded at 6 and 12 months post diagnosis in 260 consecutive patients. Results: A total of 187 patients (71.9%) attended at least 1 follow-up visit, and 105 patients (40.4%) attended 2. A total of 71/187 patients (38.0%) were spell-free at last follow-up. In contrast, 35/187 patients (18.7%) had marked increase in spell frequency postdiagnosis. Delay to diagnosis had no relationship to outcome. Patients with anxiety or depression were 2.32 times less likely to become spell-free (p = 0.012), and patients drawing social security payments at baseline were 2.34 times less likely to become spell-free (p = 0.014), than patients without those factors. Men were 2.46 times more likely to become spell-free than women (p = 0.016). While 93/187 patients (49.7%) were using emergency medical services at baseline, only 29/187 (15.5%) were using them at follow-up (p < 0.001). This was independent of whether or not the patient became spell-free. Conclusion: A substantial minority of our patients became spell-free with communication of the diagnosis the only intervention. Previous psychiatric diagnoses, social security payments, and gender were important predictors of outcome. Most patients stopped using emergency services, irrespective of whether or not spells continued. Outcomes other than spell frequency may be important in patients with psychogenic nonepileptic attacks.

Guided self-help for functional (psychogenic) symptoms A randomized controlled efficacy trial

Objectives: Functional (psychogenic or somatoform) symptoms are common in neurology clinics. Cognitive-behavioral therapy (CBT) can be an effective treatment, but there are major obstacles to its provision in practice. We tested the hypothesis that adding CBT-based guided self-help (GSH) to the usual care (UC) received by patients improves outcomes. Methods: We conducted a randomized trial in 2 neurology services in the United Kingdom. Outpatients with functional symptoms (rated by the neurologist as “not at all” or only “somewhat” explained by organic disease) were randomly allocated to UC or UC plus GSH. GSH comprised a self-help manual and 4 half-hour guidance sessions. The primary outcome was self-rated health on a 5-point clinical global improvement scale (CGI) at 3 months. Secondary outcomes were measured at 3 and 6 months. Results: In this trial, 127 participants were enrolled, and primary outcome data were collected for 125. Participants allocated to GSH reported greater improvement on the primary outcome (adjusted common odds ratio on the CGI 2.36 [95% confidence interval 1.17–4.74; p = 0.016]). The absolute difference in proportion “better” or “much better” was 13% (number needed to treat was 8). At 6 months the treatment effect was no longer statistically significant on the CGI but was apparent in symptom improvement and in physical functioning. Conclusions: CBT-based GSH is feasible to implement and efficacious. Further evaluation is indicated. Classification of evidence: This study provides Class III evidence that CBT-based GSH therapy improves self-reported general health, as measured by the CGI, in patients with functional neurologic symptoms.

Outpatient video EEG recording in the diagnosis of non-epileptic seizures: a randomised controlled trial of simple suggestion techniques

Objective: To assess the yield of recorded habitual non-epileptic seizures during outpatient video EEG, using simple suggestion techniques based on hyperventilation and photic stimulation. Design: Randomised controlled trial of “suggestion” v “no suggestion” during outpatient video EEG recording. Setting: Regional epilepsy service (tertiary care; single centre). Participants: 30 patients (22 female, 8 male), aged over 16 years, with a probable clinical diagnosis of non-epileptic seizures; 15 were randomised to each group. Main outcome measures: Yield of habitual non-epileptic seizures recorded, and requirement for additional inpatient video EEG. Results: 10/15 patients had habitual non-epileptic seizures with suggestion; 5/15 had non-epileptic seizures with no suggestion (p = 0.058; NS); 8/9 patients with a history of previous events in medical settings had non-epileptic seizures recorded during study. Logistic regression analysis with an interaction clause showed a significant effect of suggestion in patients with a history of previous events in medical settings (p = 0.003). An additional inpatient video-EEG was avoided in 14 of the 30 patients (47%). Conclusions: Habitual non-epileptic seizures can be recorded reliably during short outpatient video EEG in selected patients. Simple (non-invasive) suggestion techniques increase the yield at least in the subgroup with a history of previous events in medical settings. Inpatient video EEG can be avoided in some patients.

Gender differences in psychogenic non-epileptic seizures

PURPOSE To determine whether male and female populations of patients with psychogenic non-epileptic seizures (PNES) are similar, in terms of demographic and social factors, aetiological factors, the clinical characteristics of events and path to diagnosis. METHODS Prospective study by semi-structured interview of 160 consecutive patients (117 female and 43 male) with video EEG confirmed diagnosis of PNES + epileptic seizures (ES). RESULTS Most parameters showed no significant differences. Males were, however, more likely to be unemployed (P = 0.028), and females were six times more likely to self-harm (P = 0.050), though the numbers were small in these categories. Men were more likely to attribute their PNES to a predisposing factor for epilepsy (P = 0.001), and women were over eight times more likely to report sexual abuse (P = 0.001). Event semiology was similar, but women were more likely to weep after events (P = 0.017). The carers and family of men with PNES were three times less likely to accept the diagnosis of PNES (P = 0.017). CONCLUSIONS Our samples showed few significant gender differences, suggesting that other male and female populations of patients with PNES are likely to be similar also. Some of the differences we found may give insight into causation of PNES.

Pseudosleep events in patients with psychogenic non-epileptic seizures: prevalence and associations

Objectives: To determine the prevalence and clinical associations of a history of events during sleep in patients with psychogenic non-epileptic seizures (PNES, pseudoseizures), and to compare the prevalence of a history of sleep events with that in poorly controlled epilepsy. Methods: Prospective study by semistructured interview of the history of event patterns and their clinical associations in 142 patients with video EEG confirmed PNES, and 100 patients with poorly controlled epilepsy. Results: 84/142 patients with PNES (59%) and 47/100 with epilepsy (47%) gave a history of events during sleep (p = 0.062). In patients with PNES, significant associations were found between a history of sleep events and: convulsive clinical semiology, antiepileptic drug treatment, fatigue, suicide attempts, mood disorder, and physical abuse. A particularly strong association with social security benefit was also found (odds ratio 4.0, p<0.001). Conclusions: The prevalence of a history of sleep events is similar in PNES and epilepsy, and is of no value in discriminating between the two, although a history of events occurring exclusively during sleep does suggest epileptic seizures. The clinical associations found indicate that a combination of psychopathological and external influences may be important in determining whether or not a patient with PNES gives a history of events during sleep.

Misdiagnosis of epilepsy in patients prescribed anticonvulsant drugs for other reasons

Doctors must be clear to patients and other doctors when prescribing anticonvulsants for conditions other than epilepsy