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Bruce P Hermann

Publications and source records attributed to Bruce P Hermann.

At least 19 recordsLinked to original sources

Reduced hippocampal activation during episodic encoding in middle-aged individuals at genetic risk of Alzheimer's disease: a cross-sectional study.

BACKGROUND: The presence of the apolipoprotein E (APOE) epsilon4 allele is a major risk factor for the development of Alzheimer's disease (AD), and has been associated with metabolic brain changes several years before the onset of typical AD symptoms. Functional MRI (fMRI) is a brain imaging technique that has been used to demonstrate hippocampal activation during measurement of episodic encoding, but the effect of the epsilon4 allele on hippocampal activation has not been firmly established. METHODS: The present study examined the effects of APOE genotype on brain activation patterns in the medial temporal lobe (MTL) during an episodic encoding task using a well-characterized novel item versus familiar item contrast in cognitively normal, middle-aged (mean = 54 years) individuals who had at least one parent with AD. RESULTS: We found that epsilon3/4 heterozygotes displayed reduced activation in the hippocampus and MTL compared to epsilon3/3 homozygotes. There were no significant differences between the groups in age, education or neuropsychological functioning, suggesting that the altered brain activation seen in epsilon3/4 heterozygotes was not associated with impaired cognitive function. We also found that participants' ability to encode information on a neuropsychological measure of learning was associated with greater activation in the anterior MTL in the epsilon3/3 homozygotes, but not in the epsilon3/4 heterozygotes. CONCLUSION: Together with previous studies reporting reduced glucose metabolism and AD-related neuropathology, this study provides convergent validity for the idea that the MTL exhibits functional decline associated with the APOE epsilon4 allele. Importantly, these changes were detected in the absence of meaningful neuropsychological differences between the groups. A focus of ongoing work in this laboratory is to determine if these findings are predictive of subsequent cognitive decline.

Adult↗

Protracted ictal confusion in elderly patients.

BACKGROUND: Ictal confusion, particularly if protracted, often presents a diagnostic challenge. OBJECTIVES: To define protracted ictal confusion in elderly patients and to characterize its features and outcome. DESIGN: Case series. SETTING: Neurology outpatient and emergency departments at 2 tertiary care centers. PATIENTS: Consecutive series of 22 ambulatory patients with acute ictal confusion. MAIN OUTCOME MEASURES: Duration of ictal confusion was correlated with age and lesions noted on cerebral images and videoelectroencephalographic studies. RESULTS: The ictal basis underlying confusion was not recognized for up to 5 days in 22 patients (mean +/- SD age, 70 +/- 8.5 years). Twenty patients had partial complex status epilepticus, and 2 patients had newly diagnosed primary generalized status epilepticus. Motor movements were not present in either group, although reduced mood states and ictal neglect were noted in some patients. Fifteen patients had previous episodes (2-10) of protracted ictal confusion. Once identified, treatment reversed confusion, and eventually patients were discharged to home, although a few patients sustained persistent reduction in baseline cognition. CONCLUSIONS: Protracted ictal confusion is often not considered in the ambulatory elderly patient, with resulting delay in diagnosis. Electroencephalographic and videoelectroencephalographic studies performed while the patient is experiencing symptoms are crucial to early diagnosis and timely management.

Age Factors↗

Rapid detection of major depression in epilepsy: a multicentre study.

BACKGROUND: Depression is a common comorbid disorder in epilepsy but is not routinely assessed in neurology clinics. We aimed to create a rapid yet accurate screening instrument for major depression in people with epilepsy. METHODS: We developed a set of 46 items to identify symptoms of depression that do not overlap with common comorbid cognitive deficits or adverse effects of antiepileptic drugs. This preliminary instrument and several reliable and valid instruments for diagnosis of depression on the basis of criteria from the Diagnostic and Statistical Manual IV, depression symptom severity, health status, and toxic effects of medication were applied to 205 adult outpatients with epilepsy. We used discriminant function analysis to identify the most efficient set of items for classification of major depression, which we termed the neurological disorders depression inventory for epilepsy (NDDI-E). Baseline data for 229 demographically similar patients enrolled in two other clinical studies were used for verification of the original observations. FINDINGS: The discriminant function model for the NDDI-E included six items. Internal consistency reliability of the NDDI-E was 0.85 and test-retest reliability was 0.78. An NDDI-E score of more than 15 had a specificity of 90%, sensitivity of 81%, and positive predictive value of 0.62 for a diagnosis of major depression. Logistic regression showed that the model of association of major depression and the NDDI-E was not affected by adverse effects of antiepileptic medication, whereas models for depression and generic screening instruments were. The severity of depression symptoms and toxic effects of drugs independently correlated with subjective health status, explaining 72% of variance. Results from a separate verification sample also showed optimum sensitivity, specificity, and predictive power at a cut score of more than 15. INTERPRETATION: Major depression in people with epilepsy can be identified by a brief set of symptoms that can be differentiated from common adverse effects of antiepileptic drugs. The NDDI-E could enable rapid detection and improve management of depression in epilepsy in accordance with internationally recognised guidelines.

Adult↗

Quantitative MRI biomarkers of cognitive morbidity in temporal lobe epilepsy.

PURPOSE: To determine the relation between neuropsychological morbidity, quantitative magnetic resonance imaging (MRI) measures of whole brain structure, and clinical seizure factors reflecting epilepsy cause, course, and treatment. METHODS: Quantitative MRI measurements of total (whole brain) cerebrospinal fluid (CSF) and gray- and white-matter volumes and clinical seizure features were examined in relation to summary indices of cognitive morbidity in 96 patients with temporal lobe epilepsy. MRI volumes were adjusted for intracranial volume (ICV), and cognitive scores were adjusted for age, education, and gender, based on a sample of 82 healthy controls. RESULTS: Whole-brain volumes (gray, white, and CSF) were abnormal in chronic temporal lobe epilepsy patients compared with controls and were related significantly to neuropsychological morbidity, especially total CSF. Statistical modeling demonstrated that markers of total atrophy (CSF) was the primary mediator of the relation between clinical seizure variables and neuropsychological morbidity. CONCLUSIONS: Quantitative measurements of overall brain abnormality (atrophy) in temporal lobe epilepsy are clinically meaningful markers that are associated with increased cognitive morbidity. These biomarkers appear to mediate the adverse effects of some clinical seizure variables on cognition.

Adolescent↗

Cerebellar atrophy in temporal lobe epilepsy.

PURPOSE: The goal of this work was to determine the presence and degree of cerebellar atrophy in chronic temporal lobe epilepsy, its clinical seizure correlates, and its association with general cortical atrophy. METHODS: Study participants were 78 persons with temporal lobe epilepsy and 63 age- and gender-matched healthy controls. All subjects underwent high-resolution MRI with manual tracing of the cerebellum. Clinical seizure features and history were obtained by structured interview and review of medical records. RESULTS: The epilepsy group exhibited significant abnormality in cerebellar volume, with mean reductions ranging from 4 to 6.6% depending on adjustments. Significantly more individual subjects with epilepsy exhibited cerebellar atrophy compared with controls across all operational definitions or thresholds of abnormality including z < or = -2.0 (13% TLE, 3.4% controls) and z < or = 1.5 (22% TLE, 3.4% controls). Clinical seizure features reflecting both neurodevelopmental (history of initial precipitating injuries) and severity of course (longer duration, increased number of lifetime generalized tonic-clonic seizures) factors were associated with cerebellar atrophy. Atrophy of the cerebellum could be observed independent of more general (cerebral) atrophic processes. CONCLUSIONS: The presence of cerebellar atrophy is a reflection of the extratemporal abnormalities that can be observed in localization-related temporal lobe epilepsy, which may be due, at least in part, to factors associated with epilepsy chronicity.

Adult↗

Temporal lobe epilepsy and the selective reminding test: the conventional 30-minute delay suffices.

Conventional memory assessment may fail to identify memory dysfunction characterized by intact recall for a relatively brief period but rapid forgetting thereafter. This study assessed learning and retention after 30-min and 24-hr delays on auditory and visual selective reminding tests (SRTs) in right (n=20) and left (n=22) temporal lobe epilepsy (TLE) patients and controls (n=49). The left TLE group performed significantly worse than controls on all 3 trials of both tests. The right TLE group differed from the controls on all 3 visual SRT trials and on learning for the auditory SRT. There were no between-groups differences in rate of information lost at the 30-min versus the 24-hr delay. At the individual level, there was no difference in the percentage of patients versus controls who demonstrated isolated memory impairment at the 24-hr delay. Accelerated forgetting over 24 hr is uncommon in TLE patients.

Adolescent↗

Sleep architecture in children with idiopathic generalized epilepsy.

PURPOSE: Children with epilepsy experience sleep disturbances, behavioral and attentional problems at higher rates than their peers. However, the relation between sleep disturbances and the observed behavioral and attentional abnormalities is poorly defined. METHODS: Children with primary generalized epilepsy who were seizure free and between the ages of 5 and 18 years were matched with age- and gender-matched healthy controls and underwent two consecutive nights of nocturnal polysomnography with extended electroencephalography. Connor's Continuous Performance Test (CPT) was administered to assess daytime attentional function. Parents completed the Child Behavior Checklist (CBCL) to assess their emotional-behavioral status. Two sample t tests were used to examine group differences. Spearman correlations were used to examine the relation between sleep variables and behavior and attention variables. Multiple regression analysis was used to identify independent predictors of abnormal behavior and attention among patients. RESULTS: Eleven children with primary generalized epilepsy and eight age- and sex-matched controls participated in the study. Children with epilepsy had longer stage 1 sleep percentage (7.19 +/- 3.2 vs. 4.8 +/- 3.5; p = 0.05) and latency to rapid-eye-movement (REM) sleep (123.5 +/- 40.1 vs. 101.75 +/- 24.3; p = 0.018) compared with controls. Children with epilepsy had worse attention (CPT index, 10.94 +/- 6.55 vs. 3.42 +/- 4.04; p = 0.004) and exhibited significantly higher CBCL Total Behavior and Internalizing Behavior Problem scales. Whereas regression analysis showed no independent predictors of abnormal behavior and attention, a tendency toward association between CBCL total behavior scale and REM percentage (r= 0.55; p = 0.07), and between CPT overall index and stage 1 sleep percentage (r= 0.40; p = 0.10) was noted. CONCLUSIONS: Sleep architecture is abnormal in children with primary generalized epilepsy. Further studies are needed to determine whether abnormalities in sleep architecture contribute to poor daytime behavior and attention.

Adolescent↗

Screening for major depression in epilepsy with common self-report depression inventories.

PURPOSE: Major depression is a common psychiatric comorbidity in chronic epilepsy that is frequently unrecognized and untreated. A variety of self-report mood inventories are available, but their validity as well as ability to detect major depression in epilepsy remains uncertain. The purpose of this study was to determine the ability of two common depressive symptom inventories to identify major depression in people with epilepsy. METHODS: In total, 174 adult patients with epilepsy underwent standardized psychiatric interview techniques [Mini International Neuropsychiatric Interview (MINI) and Mood Disorders module of the Structured Clinical Interview for DSM-IV Axis I Disorders-Research Version (SCID-I)] to determine the presence of current major depression. Subjects completed two self-report depression inventories [Beck Depression Inventory-II (BDI-II), Center for Epidemiological Study of Depression (CES-D)]. The ability of these self-report measures to identify major depression as identified by the gold standard structured interviews was examined by using diagnostic efficiency statistics. RESULTS: Both the BDI-II and the CES-D exhibited significant ability to identify major depression in epilepsy. All ROC analyses were highly significant (mean area under the curve, 0.92). Mean sensitivity (0.93) and specificity (0.81) were strong, with excellent negative predictive value (0.98) but lower positive predictive value (0.47). CONCLUSIONS: Common self-report depression measures can be used to screen for major depression in clinical settings. Use of these measures will assist in the clinical identification of patients with major depression so that treatment can be initiated.

Adult↗

Clinical assessment of Axis I psychiatric morbidity in chronic epilepsy: a multicenter investigation.

This study characterizes the rate of current Axis I DSM-IV disorders using a brief standardized psychiatric interview procedure, the Mini International Neuropsychiatric Interview (v5.0) (MINI), and determined the validity of MINI diagnoses of current depressive episodes to the research standard (Structured Clinical Interview for DSM-IV Disorders [SCID]). One hundred seventy-four patients with chronic epilepsy from five tertiary medical centers were interviewed using the MINI and the mood disorders module of the SCID. Current Axis I disorders were evident in one-half the sample (49%), with prevalent anxiety (30.4%) and mood (21.8%) disorders. Major depressive episode was the most common individual diagnosis (17.2%). Concordance was high between the MINI and SCID for diagnoses of current depression, especially for major depression. Of those with current major depression, less than one-half were treated with antidepressant medications. Current Axis I DSM-IV diagnoses can be effectively and accurately identified in clinical settings using shorter standardized psychiatric interview techniques. Issues regarding recognition and treatment of psychiatric morbidity in epilepsy are discussed.

Adult↗

Voxel-based morphometry of unilateral temporal lobe epilepsy reveals abnormalities in cerebral white matter.

Voxel-based morphometric (VBM) investigations of temporal lobe epilepsy have focused on the presence and distribution of gray matter abnormalities. VBM studies to date have identified the expected abnormalities in hippocampus and extrahippocampal temporal lobe, as well as more diffuse abnormalities in the thalamus, cerebellum, and extratemporal neocortical areas. To date, there has not been a comprehensive VBM investigation of cerebral white matter in nonlesional temporal lobe epilepsy. This study examined 25 lateralized temporal lobe epilepsy patients (13 left, 12 right) and 62 healthy controls in regard to both temporal and extratemporal lobe gray and white matter. Consistent with prior reports, gray matter abnormalities were evident in ipsilateral hippocampus and ipsilateral thalamus. Temporal and extratemporal white matter was affected ipsilateral to the side of seizure onset, in both left and right temporal lobe epilepsy groups. These findings indicate that chronic temporal lobe epilepsy is associated not only with abnormalities in gray matter, but also with concomitant abnormalities in cerebral white matter regions that may affect connectivity both within and between the cerebral hemispheres.

Adolescent↗

Memory relationships between MRI volumes and resting PET metabolism of medial temporal lobe structures.

Prior studies of temporal lobe epilepsy (TLE) patients showed that MRI volumes and resting PET scan measures of temporal lobe structures were related to memory. Weintrob and colleagues [Ann. Neurol. 2002;51:442-7] reported that PET glucose uptake in the left perirhinal cortex predicted verbal paired associate (PA) learning, whereas MRI volume of the left hippocampus did not. We investigated whether MRI volumes could account for memory functioning if both PET and volumes were from the same region in 18 TLE patients. Volumes and glucose uptake of the hippocampus and parahippocampal gyrus (PHG) were compared with WMS-III performance. Significant correlations were observed between hippocampal volumes and PA and Logical Memory (LM) Percent Retention, but not between memory and PHG volumes or any PET measures. Multiple regression revealed that hippocampal volumes, but not PHG volumes or PET, significantly predicted PA and LM retention scores. These findings suggest that hippocampal volumes provide unique information regarding memory.

Adolescent↗

Quantitative measurement of cortical surface features in localization-related temporal lobe epilepsy.

Differences in cortical surface features between healthy controls (n = 48) and patients with temporal lobe epilepsy (n = 46), ages 14-59, were characterized by means of advanced quantitative MRI processing techniques. Cortical surface features of interest included gyral and sulcal curvature, cortical depth, and total cortical surface area. Epilepsy patients and controls differed on measures of gyrification; the abnormalities generalized despite the focal nature of the primary epileptic process. Changes in cortical surface features were associated with increasing chronological age in both groups. Abnormalities in gyrification were associated with cognitive performance and with other morphometric measurements (e.g., surface cerebral spinal fluid). These findings are related to the literature regarding morphometric changes associated with temporal lobe epilepsy and normal aging.

Adolescent↗

Significant discrepancies between immediate and delayed WMS-III indices are rare in temporal lobe epilepsy patients.

Initial factor analysis of Wechsler Memory Scale-Third Edition (WMS-III) standardization data resulted in a five-factor model that included separate immediate (IMM) and delayed (DEL) memory factors for auditory (AUD) and visual (VIS) memory. However, recent factor analyses that revealed three factors--AUD, VIS, and working memory--were discovered to be more accurate. Continued use of separate WMS-III IMM and DEL indices has been recommended because future studies with clinical groups might support this distinction. Data from this investigation of 88 temporal lobe epilepsy (TLE) patients suggested separate IMM and DEL WMS-III indices are not necessary in this population. Results were as follows: 1) There was no significant difference between the IMM and DEL indices for AUD or VIS memory. 2) The percentage of individuals with a significant difference between the IMM and DEL indices (IMM minus DEL >11 or <-12) was similar for our TLE group and the standardization sample. 3) The mean percent retention standard score (SS) was at the average level for the four memory subtests, and for each subtest only about 10% of the TLE patients had impaired scores. 4) Hippocampal volumes correlated significantly with both IMM and DEL indices. These data suggest that combining the appropriate WMS-III IMM and DEL memory subtest scores to form AUD and VIS memory indices is appropriate for TLE patients.

Adult↗

Neuropsychological predictors of academic underachievement in pediatric epilepsy: moderating roles of demographic, seizure, and psychosocial variables.

PURPOSE: Academic underachievement is common in pediatric epilepsy. Attempts to identify seizure and psychosocial risk factors for underachievement have yielded inconsistent findings, raising the possibility that seizure and psychosocial variables play a complex role in combination with other variables such as neuropsychological functioning. This study cross-validated a neuropsychological measurement model for childhood epilepsy, examined the relation between neuropsychological functioning and academic achievement, and tested the degree to which demographic, seizure, and psychosocial variables moderate that relation. METHODS: Children with chronic epilepsy (N = 173; ages 8 to 15 years; 49% girls; 91% white/non-Hispanic; 79% one seizure type; 79% taking one medication; 69% with active seizures) completed a comprehensive neuropsychological battery. Children diagnosed with mental retardation were excluded. RESULTS: Structural equation modeling identified a three-factor measurement model of neuropsychological function: Verbal/Memory/Executive (VME), Rapid Naming/Working Memory (RN/WM), and Psychomotor (PM). VME and RN/WM were strongly related to reading, math, and writing; PM predicted writing only. Family environment moderated the impact of neuropsychological deficits on writing (p < or = 0.01) and possibly for reading (p = 0.05); neuropsychological deficits had a smaller impact on achievement for children in supportive/organized homes compared with children in unsupportive/disorganized homes. CONCLUSIONS: These findings lend partial support for our theoretical model showing direct effects of neuropsychological function on achievement and the moderating role of family factors. This study suggests that a subgroup of children with epilepsy (those who have not only neuropsychological deficits but also disorganized/unsupportive home environments) are particularly at risk for adverse academic outcomes. Implications for intervention are discussed.

Adolescent↗

The relative impact of anxiety, depression, and clinical seizure features on health-related quality of life in epilepsy.

PURPOSE: To determine the independent effects of depression and anxiety on health-related quality of life (HRQOL) in epilepsy as well as the relative explanatory power of psychiatric comorbidity compared with demographic and clinical epilepsy variables (e.g., seizure frequency, severity, and chronicity). METHODS: Subjects (n = 87) with temporal lobe epilepsy completed self-report measures of depression, anxiety, HRQOL, and seizure severity. Information was derived regarding subjects' seizure frequency, duration, and treatment. HRQOL status (QOLIE-89) was examined in relation to self-reported symptoms of anxiety and depression, clinical seizure features, and demographic characteristics. RESULTS: Depression and anxiety were independently associated with reduced HRQOL. Psychiatric comorbidity explained more variance in HRQOL than did combined groups of clinical seizure or demographic variables. Although weaker in explanatory power than psychiatric comorbidity, several epilepsy factors were nonetheless significantly related to HRQOL, including seizure frequency, severity, and chronicity. CONCLUSIONS: Interictal anxiety and depression exert independent adverse effects on HRQOL. In addition, frequent, severe, and chronic seizures reduce HRQOL, but appear less powerful predictors of HRQOL than interictal psychiatric symptoms. Recognition and treatment of comorbid depression and anxiety is an important consideration in improving quality of life in epilepsy.

Adult↗

Rates and risk factors for suicide, suicidal ideation, and suicide attempts in chronic epilepsy.

Studies of causes of death among people with epilepsy suggest that the lifetime prevalence rate of suicide is elevated. Although not all of the studies have reported an increased risk for suicide, the collective data yield an average rate of approximately 12% among people with epilepsy, compared with 1.1-1.2% in the general population. The increased risk for suicide appears to affect children and adolescents as well as adults. Rates of suicide attempts have also been reported to be elevated among people with epilepsy. A suicide attempt is a significant risk factor for completed suicide. Certain psychiatric disorders, including primary mood disorders, also increase the risk for suicide. Among people with epilepsy, psychiatric comorbidity is common, and rates of mood disorders, particularly major depression, have consistently been reported to be elevated. Other potential risk factors are family issues, physical health, personality, life stress, previous suicidal behavior, and access to firearms. Assessing severity of risk helps to determine the appropriate level of intervention. The suicidality module of the Mini-International Neuropsychiatric Interview is a practical tool to help quantify current suicide risk.

Chronic Disease↗

Confirmatory factor analysis of the WMS-III in patients with temporal lobe epilepsy.

Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions.

Adult↗