Predicting psychogenic non-epileptic seizures from serum levels of neuropeptide Y and adrenocorticotropic hormone.

OBJECTIVE: Patients with psychogenic non-epileptic seizures (PNES) may present with convulsive events that are not accompanied by epileptiform brain activity. Video-electroencephalography (EEG) monitoring is the gold standard for diagnosis, yet not all patients experience convulsive episodes during video-EEG sessions. Hence, we aimed to construct a predictive model in order to detect PNES from serum hormone levels, detached from an evaluation of patients' convulsive episodes. METHODS: Fifteen female patients with PNES and 60 healthy female controls participated in the study, providing blood samples for hormone analysis. A binomial logistic regression model and the leave-one-out cross-validation were employed. RESULTS: We found that levels of neuropeptide Y and adrenocorticotropic hormone were the optimal combination of predictors, with over 90% accuracy (area under the curve=0.980). CONCLUSIONS: The ability to diagnose PNES irrespective of convulsive events would represent an important step considering its feasibility and affordability in daily clinical practice.

Vulnerability to psychogenic non-epileptic seizures is linked to low neuropeptide Y levels.

Psychogenic non-epileptic seizures (PNES) is a conversion disorder that reflects underlying psychological distress. Female patients with PNES often present with a history of prolonged stressors, especially sexual abuse. In the current study, we studied the relationship between neuropeptide Y (NPY) and PNES symptoms in women with a history of sexual abuse. NPY has been associated with resilience to stress and we hypothesized that low levels would increase the extent and severity of PNES symptoms in this patient population. Serum levels of NPY, and related hormones were measured in fifteen female PNES patients and sixty female controls. PNES patients reported more severe abuse histories, feeling of abandonment, and decreased perception of quality of life than controls. Importantly, they also had lower NPY levels. Our analysis indicates that low levels of NPY in PNES may confer greater vulnerability to exhibit seizure-like symptoms and lower quality of life.

The NAB shape learning subtest as a predictor of lateralized seizure onset.

This study presents the first empirical evaluation of the predictive value of the Neuropsychological Assessment Battery Shape Learning (NAB-SL) subtest in a sample of patients with unilateral temporal lobe epilepsy. Stimulus characteristics of the NAB-SL may improve predictive ability over other commonly used visual memory tests. Forty-nine patients with unilateral temporal lobe epilepsy were compared on measures of non-verbal and verbal memory (NAB-SL and Wechsler Memory Scale-III subtests). Univariate and forward conditional logistic regressions identified predictive values for each memory test individually and in combination. The NAB-SL delayed memory demonstrated consistently stronger predictive power over visual reproduction at the univariate and multivariate levels. The NAB-SL was a good predictor (80% range) of lateralized seizure onset when combined with a verbal memory measure. These preliminary results provide support for the use of the NAB-SL in preoperative epilepsy evaluations as a predictor of non-dominant temporal lobe dysfunction. Potential benefits of this test are discussed.

Motivation, psychopathology, locus of control, and quality of life in women with epileptic and nonepileptic seizures.

To examine factors that may potentially aid in the differential diagnosis and subsequent tailoring of treatment for patients with epileptic (ES) and psychogenic nonepileptic (PNES) seizures, thirty female patients with PNES and 51 female patients with temporal lobe epilepsy were assessed in the areas of motivation, psychopathology, health-related locus of control (HRLOC), and health-related quality of life (HRQOL). The two groups demonstrated equivalent levels of motivation, clinically elevated yet comparable mood symptoms, and no general differences in HRLOC. Despite similar mood disturbances in both groups, the participants with PNES had a later age of seizure onset, exhibited greater personality disturbances, attributed more control over their condition to nonphysicians, and endorsed a greater negative impact of their seizures on physical and emotional aspects of HRQOL. Preliminary analyses suggest that chronic anxiety and overall HRQOL may be core discriminators between these seizure groups. Addressing such issues may prove useful in tailoring more specific treatments for these etiologically disparate conditions.

A comprehensive neuropsychological profile of women with psychogenic nonepileptic seizures.

The purpose of this study was to compare the neuropsychological profile of women with VEEG-confirmed diagnoses of psychogenic nonepileptic seizures (PNES) with that of an age- and education-matched group of women with left temporal lobe epilepsy (LTLE). Results indicate that in a relatively homogenous PNES sample, no severe neurocognitive impairments were present, further supporting a psychologically versus neurologically driven pathology of PNES. In comparison to age-stratified normative data, the PNES group demonstrated only a modest deficiency across neuropsychological domains and a relative area of weakness in attention and working memory, and generally outperformed their counterparts with LTLE. Although the attentional deficits in the PNES group may have been influenced by their elevated levels of emotional distress, symptoms of depression and anxiety were significant and common in both patients with PNES and those with LTLE, and therefore, the utility of psychological factors in discriminating these groups is limited. The present findings warrant the use of longitudinal research with patients with PNES to identify changes in the presentation of this condition as well as its subsequent neurocognitive and emotional impairments.

Time to first interictal epileptiform discharge in extended recording EEGs.

The presence of interictal epileptiform discharges (IEDs) in the outpatient interictal EEG can provide evidence for a diagnosis of epilepsy and support for a specific epilepsy syndrome. However, there is variation in the duration of outpatient EEGs, and prolonged EEGs may have a higher yield for IEDs. The authors retrospectively reviewed 172 routine, extended, outpatient EEGs of at least 60 minutes duration in adults to determine the time to the first IED. The mean duration was 187 minutes. Twenty-six percent captured IEDs. The initial IED occurred in the first 20 minutes in 53% and after 20 minutes in 47%. The mean time to the first IED was 32.8 minutes with a range of 1 to 216 minutes and a standard deviation of 48.2 minutes. Results were skewed to the right (skew 2.22) with a median time to the first IED of 10 minutes. There was a longer time to the first IED in temporal epileptiform discharges compared with generalized discharges.

Seizure-related motor vehicle crashes in Arizona before and after reducing the driving restriction from 12 to 3 months.

OBJECTIVE: To evaluate whether changing the seizure-free interval in Arizona from 12 months to 3 months affected the number of seizure-related motor vehicle crashes. METHODS: We performed a time trend study with analysis of motor vehicle crash reports in the state of Arizona 3 years before (1991-1993) and 3 years after (1994-1996) the seizure-free interval was decreased from 12 to 3 months. The number of motor vehicle crashes related to seizures, other medical conditions, and other nonmedical crashes was compared before and after the law changed. Other population trends, including population growth, registered vehicles, and registered drivers, are also reported. RESULTS: Seizure-related crashes increased from 125 to 136 for the 3 years before and 3 years after the law changed, respectively. The total rate of seizure-related crashes did not increase on the basis of an incidence rate difference of -0.03/10(9) miles (95% confidence interval [CI], -0.30 to 0.24) and a relative risk of 0.98 (95% CI, 0.77 to 1.24). Over the same time interval, crashes related to other medical conditions increased from 288 to 310, respectively, for an incidence rate difference of -0.09/10(9) miles (95% CI, -0.51 to 033) and a relative risk of 0.97 (95% CI, 0.82 to 1.13). Fatalities due to seizure-related crashes decreased during the same period, whereas the number of multiple vehicle crashes increased. CONCLUSION: The rate of seizure-related crashes did not significantly increase in the state of Arizona after the seizure-free interval was reduced from 12 to 3 months.

Neurologic complications of sit-ups associated with the Valsalva maneuver: 2 case reports.

We present 2 cases of potentially catastrophic neurologic consequences occurring in healthy individuals engaged in sit-up exercises. Two young healthy men were engaged in sit-ups when one developed a stroke and the other developed a spinal epidural hematoma. The Valsalva maneuver involved in the sit-up exercise can produce supraphysiologic increases in blood pressure, which can lead to vascular injury and serious neurologic consequences. Proper breathing should be encouraged and patients with known predisposing factors should avoid such exercises. Prompt recognition of neurologic signs and symptoms during exercise can be life saving. This is the first report of the neurologic complications of sit-ups.