The prevalence of epilepsy and association with traumatic brain injury in veterans of the Afghanistan and Iraq wars.

OBJECTIVE: To examine the association of epilepsy with traumatic brain injury (TBI) in Afghanistan and Iraq (Operation Enduring Freedom [OEF]/Operation Iraqi Freedom [OIF]) Veterans. DESIGN: Cross-sectional observational study. PARTICIPANTS: A total 256 284 OEF/OIF Veterans who received inpatient and outpatient care in the Veterans Health Administration in fiscal years 2009-2010. MAIN OUTCOME MEASURES: We used algorithms developed for use with International Classification of Diseases, Ninth Revision, Clinical Modification, codes to identify epilepsy, TBI (penetrating TBI [pTBI]/other TBI), and other risk factors for epilepsy (eg, stroke). TBI and other risk factors were identified prior to the index date (first date of seizure or October 1, 2009) for primary analyses. RESULTS: Epilepsy prevalence was 10.6 per 1000 (N = 2719) in fiscal year 2010; age-adjusted prevalence was 6.1. Of 37 718 individuals with a diagnosis of TBI, 29 297 Veterans had a diagnosis of TBI prior to the index date. Statistically significant associations were found between epilepsy and prior TBI diagnosis (pTBI: adjusted odds ratio = 18.77 [95% confidence interval, 9.21-38.23]; other TBI: adjusted odds ratio = 1.64 [1.43-1.89]). CONCLUSIONS: Among OEF/OIF Veterans, epilepsy was associated with previous TBI diagnosis, with pTBI having the strongest association. Because war-related epilepsy in Vietnam War Veterans with TBI continued 35 years postwar, a detailed, prospective study is needed to understand the relationship between epilepsy and TBI severity in OEF/OIF Veterans.

The rate of psychiatric disorders in veterans undergoing intensive EEG monitoring is associated with symptom and performance invalidity.

To determine if the number of participants with psychiatric disorders increased in association with failures on symptom validity tests (SVTs) and a performance validity test (PVT) in Veterans admitted for evaluation of possible seizures.The 254 participants were Veterans undergoing inpatient video-EEG monitoring for the diagnosis of possible seizures. DSM-IV psychiatric disorders were diagnosed with the SCID IV. Symptom exaggeration was assessed with the MMPI-2-RF and performance validity with the TOMM.On the MMPI-2-RF, 27.6%-32.7% showed symptom exaggeration. Participants who exaggerated on the MMPI-2-RF were more often diagnosed with psychiatric disorders. The TOMM was failed by 15.4% of the sample. Participants who failed the TOMM were more often diagnosed with an Axis I disorder but not with a personality disorder. The MMPI-2-RF was invalid in more cases than the TOMM, but 7.9% of the sample generated a valid MMPI-2-RF and an invalid TOMM.The correlational design does not allow conclusions about cause and effect. The invalid groups may have had a higher rate of psychopathology. The number of participants with psychiatric disorders increased in association with symptom exaggeration and performance invalidity. Symptom exaggeration was more frequent than performance invalidity, but the TOMM made a unique contribution to identification of invalidity. The routine clinical use of SVTs and PVTs is supported. The results also suggest the need for caution in diagnosing psychiatric disorders when there is symptom exaggeration or performance invalidity, because diagnostic validity is dependent on the accuracy of symptom reporting.

RBANS Validity Measures and the TOMM in Veterans Undergoing Seizure Monitoring.

OBJECTIVE: To assess the validity of embedded measures of performance validity, the effort index (EI) and effort scale (ES) of the repeatable battery for the assessment of neuropsychological status (RBANS), in Veterans with seizures; to compare the frequency of failure on the test of memory malingering (TOMM) in patients with epileptic versus psychogenic nonepileptic seizures (PNES). METHODS: Seizure diagnosis was established for 309 participants in epilepsy monitoring units using conventional diagnostic criteria who completed both the TOMM and RBANS. The criterion for performance invalidity was failure on any trial of the TOMM. We examined multiple EI and ES cutoffs to establish optimal sensitivity and specificity. RESULTS: An RBANS EI cutoff score of greater than three was optimal with specificity of .98, sensitivity of.19, and positive Likelihood Ratio of 10 but was not useful when below this cutoff. Confidence intervals indicate the need for confirmation of a failed EI with another performance validity test (PVT). No ES cutoff had sufficient specificity for clinical use. Invalid TOMM performance but not invalid RBANS performance was significantly more common in persons with PNES than in persons with epileptic seizures. CONCLUSIONS: In Veterans undergoing seizure monitoring, the RBANS EI was useful as a screen when positive that requires confirmation with another PVT. The RBANS ES was not useful. Invalid performance on the TOMM was more common in persons with PNES than in persons with epileptic seizures.

Demographic and historical backgrounds of the elderly with nonepileptic seizures: a comparative study.

BACKGROUND: Non-epileptic seizures (NES) are not infrequent in the elderly. However, the data on NES in the elderly is likited. AIM: To study the demographic and historical background of eldely patients with NES and compare the same with the data in the younger patients with NES. MATERIALS AND METHODS: Patients with NES over 55 years of age and the next two consecutive patients with NES between ages 18 and 45 were compared in terms of demographic and historical features, psychiatric evaluation and MMPI testing. RESULTS: Of all the 128 patients with NES, 13 (10.6%) were over 55 years of age. History of physical/sexual abuse was high in both the groups. The mean length of time for NES diagnosis was longer in the elderly (13.38 +/- 15.33 vs. 6.15 +/- 8.04 years; P < 0.05). Majority of the patients with NES were on AEDs without evidence of epilepsy and almost half in both the groups were using benzodiazepines. CONCLUSION: In demographic and historical aspects old and young patients do not display major differences; however, the diagnosis is significantly delayed in the elderly. Early diagnosis with video EEG is recommended to avoid potential long-term risks associated with inappropriate treatments.

The Portland Neurotoxicity Scale: validation of a brief self-report measure of antiepileptic-drug-related neurotoxicity.

The Portland Neurotoxicity Scale (PNS) is a brief patient-based survey of neurotoxicity complaints commonly encountered with the use of antiepileptic drugs (AEDs). The authors present data on the validity of this scale, particularly when used in longitudinal studies. Participants included 55 healthy controls, 23 epilepsy patient controls, and 86 healthy volunteers who took various AEDs or placebos for 12 weeks as part of randomized, double-blind studies of AED effects on cognitive abilities. Test-retest reliability in the control groups averaged .80 (total score). Test-retest changes in the PNS were sensitive to AED usage in general (p < .001) and to each of the five AEDs tested but not to placebo. Test-retest changes in the PNS were strongly correlated with several scales of the Profile of Mood States but only weakly correlated with objective cognitive test measures. The PNS has satisfactory psychometric properties and is sensitive to AED usage in test-retest studies.

MMPI-2 profiles: fibromyalgia patients compared to epileptic and non-epileptic seizure patients.

We compared MMPI-2 profiles of Gulf War veterans with fibromyalgia (FM) to epileptic seizure (ES) patients, psychogenic non-epileptic seizure (PNES) patients, and Gulf War veteran healthy controls. Both PNES and FM are medically unexplained conditions. In previous MMPI-2 research PNES patients were shown to have significantly higher Hs and Hy clinical scales than ES patients. In the present research the FM group had significantly higher Hs and Hy scale scores than both the ES group and the healthy control group. There was no significant difference between the FM and PNES Hs scale scores; however, the FM Hy scale score was significantly lower than the PNES Hy scale score. Present findings indicate a high level of psychological distress in the FM group.

Psychogenic nonepileptic seizures.

Neurological, neurodiagnostic, and neuropsychological aspects of psychogenic nonepileptic seizures (PNES) are reviewed, including psychosocial, psychiatric, cognitive, and MMPI-2 findings.

MMPI-2 profiles of persons with multiple chemical sensitivity.

We compared the MMPI-2 profiles of adults with multiple chemical sensitivity (MCS), epileptic seizures (ES), and nonepileptic seizures (NES). Both NES and MCS are medically unexplained conditions. In previous studies profiles associated with NES were elevated on scales Hs and Hy, compared with profiles associated with ES. We predicted that profiles associated with MCS would be elevated on Hs and Hy compared with the ES group. Patients with ES and NES were diagnosed after intensive EEG monitoring using published criteria. MCS was diagnosed if there was a complaint of illness in response to multiple common odors at levels that are not noxious to most people. All the MCS cases had legal claims for injury related to chemical exposures. The results showed that on MMPI-2 scales Hs, D, and Hy the MCS group had means significantly higher than both the ES and NES groups. Fake Bad Scale scores were elevated in 11 MCS cases, and regression-based estimates of Fake Bad Scale scores showed elevation in the MCS group compared with both seizure groups. We conclude that MMPI-2 data, obtained from people seeking financial compensation, indicate that there is a strong psychological component to MCS symptoms.

Vagus Nerve Stimulation As Treatment for Epileptic Seizures.

Vagus nerve stimulation is a unique therapy for epileptic seizures. Two randomized controlled trials in patients with medically refractory partial seizures have demonstrated efficacy, leading to US Food and Drug Administration approval of vagus nerve stimulation therapy in 1997. Extensive safety testing has not revealed significant effects on cardiac, respiratory, or gastrointestinal function, though recent reports of intraoperative asystole and sleep-related airway obstruction have raised concerns. Vagus nerve stimulation is indicated for adjunctive therapy of partial-onset seizures in children and individuals older than 12 years (Class I evidence). Based on controlled, randomized trials, approximately 30% of these patients can be expected to have at least a 50% decrease in overall seizure frequency. Vagus nerve stimulation efficacy is similar to that of several newer antiepileptic drugs when used in similar populations in controlled, randomized trials. Long-term follow-up studies suggest continued efficacy over more than 1 year (Class III evidence). Case series suggest similar or greater efficacy in younger children, and in patients with refractory generalized seizures, including those associated with the Lennox-Gastaut syndrome (Class III evidence). Vagus nerve stimulation is appropriate therapy for patients with medically refractory epileptic seizures who are not optimal candidates for resective epilepsy surgery.

Assessment of CNS effects of antiepileptic drugs by using quantitative EEG measures.

PURPOSE: Antiepileptic drugs (AEDs) can be associated with adverse neurologic effects including cognitive dysfunction. Objective methods for recognizing AED effects on the brain could be valuable for long-term management. We compared quantitative EEG measures and cognitive tests in a group of patients beginning or ending AED therapy. METHODS: Subjects included 20 patients beginning AED therapy (AEDon), 12 patients stopping AED therapy (AEDoff), 33 patient controls receiving stable AED therapy (AEDco), and 73 healthy controls (Nco). All subjects underwent structured EEG recording and a cognitive test battery before change in AED dose and again 12-16 weeks later, >or=4 weeks after the last dose change. Four occipital EEG measures (peak frequency, median frequency, relative theta and delta power) were analyzed. Cognitive test changes were scored by using test-retest regression equations based on the Nco subjects. Wilcoxon tests were used for two-group comparisons. RESULTS: AEDons had a significant decrease, and AEDoffs, a significant increase in the peak frequency of the EEG rhythm, as compared with controls. Results for median frequency and theta power were similar. Change in the EEG peak frequency correlated with an aggregate cognitive change measure (r2= 0.71; p < 0.001), individual cognitive measures, and subjective complaints. Of the combined AEDon/AEDoff patients, 58% exceeded the 95% confidence interval for test-retest change in EEG peak frequency. CONCLUSIONS: Quantitative measures derived from the occipital EEG are sensitive to AEDs and correlate with AED-related cognitive effects and subjective complaints. Although this correlation does not indicate a direct relation, quantified EEG may be a practical measure of AED impact on the brain.

Effects of gabapentin and carbamazepine on the EEG and cognition in healthy volunteers.

PURPOSE: Antiepileptic drug (AED) therapy can be associated with neurotoxic side effects including cognitive dysfunction. Objective methods for detection of neurotoxicity in individual patients would be useful. We studied the effects of gabapentin (GBP) and carbamazepine (CBZ) on neurophysiologic and cognitive/behavioral measures in healthy volunteers. METHODS: In a 12-week, randomized, double-blind, parallel-group study of CBZ and GBP in healthy volunteers, 23 subjects completed the protocol. All achieved the target dose of 1,200 mg CBZ or 3,600 mg GBP. A structured EEG for quantitative analysis and a cognitive test battery were administered before AED therapy and again after 12 weeks of therapy. Test-retest differences were compared with those of 72 untreated control subjects. RESULTS: Both CBZ and GBP significantly decreased the peak frequency of the posterior (alpha) rhythm, with CBZ exerting a greater effect. Ten CBZ and six GBP subjects exceeded the 95% confidence interval (CI) for an individual. Cognitive tests revealed AED vs. control group effects for two of seven measures (Digit Symbol, Stroop) and all subjective measures. However, few subjects exceeded the 95% CI for any objective test. Differences between CBZ and GBP were not significant. Greater EEG slowing was associated with greater subjective neurotoxicity and poorer test-retest performance on a cognitive test summary measure. CONCLUSIONS: Prolonged CBZ and GBP therapy induced EEG slowing that correlated with cognitive complaints and often exceeded the confidence interval for individual subjects. Quantitative EEG measures may be useful in the objective determination of AED-related neurotoxicity.