Pain Influences Neuropsychological Performance Following Electrical Injury: A Cross-Sectional Study.

OBJECTIVE: Electrical injury (EI) is a significant, multifaceted trauma often with multi-domain cognitive sequelae, even when the expected current path does not pass through the brain. Chronic pain (CP) research suggests pain may affect cognition directly and indirectly by influencing emotional distress which then impacts cognitive functioning. As chronic pain may be critical to understanding EI-related cognitive difficulties, the aims of the current study were: examine the direct and indirect effects of pain on cognition following EI and compare the relationship between pain and cognition in EI and CP populations. METHOD: This cross-sectional study used data from a clinical sample of 50 patients with EI (84.0% male; Mage = 43.7 years) administered standardized measures of pain (Pain Patient Profile), depression, and neurocognitive functioning. A CP comparison sample of 93 patients was also included. RESULTS: Higher pain levels were associated with poorer attention/processing speed and executive functioning performance among patients with EI. Depression was significantly correlated with pain and mediated the relationship between pain and attention/processing speed in patients with EI. When comparing the patients with EI and CP, the relationship between pain and cognition was similar for both clinical groups. CONCLUSIONS: Findings indicate that pain impacts mood and cognition in patients with EI, and the influence of pain and its effect on cognition should be considered in the assessment and treatment of patients who have experienced an electrical injury.

The relationship between neuropsychological dispersion, processing speed and memory after electrical injury.

Introduction: Previous studies of neuropsychological performance in electrical injury (EI) patients have produced evidence of deficits in various cognitive domains, but studies have yet to investigate relationships among performance in cognitive domains post-EI. This study examined whether dispersion among neuropsychological test scores was associated with injury parameters and neuropsychological performance in EI patients. Additionally, we examined whether dispersion, processing speed and/or executive abilities explain variance in episodic verbal and visual memory performance among EI patients.Method: Data from 52 post-acute EI patients undergoing outpatient evaluation with objectively-verified valid neuropsychological test performance were examined. Tests included measures of verbal and visual memory, processing speed, and executive functioning. Dispersion was calculated from executive functioning and processing speed scores.Results: Dispersion was not related to mean performance or injury characteristics, but was significantly negatively correlated with performance on a test of processing speed, suggesting that increased dispersion is associated with reduced cognitive efficiency post-EI. Delayed visual memory was related to both dispersion scores and processing speed. Stepwise regression equations predicting delayed memory determined that processing speed most significantly predicted delayed visual memory, even after controlling for immediate visual memory. No significant relationships emerged between verbal memory and non-memory neuropsychological scores.Conclusions: This is the first study to examine neuropsychological dispersion and relationships among domains of cognitive functioning in EI. Current results suggested that neuropsychological dispersion is not a marker of general functioning or severity of injury in EI patients, but may represent more specific processing speed abilities. Processing speed predicts delayed visual memory performance in EI patients, which should be considered in interpreting test scores during evaluations.

Establishing the base rate of performance invalidity in a clinical electrical injury sample: Implications for neuropsychological test performance.

Objective: The base rate of neuropsychological performance invalidity in electrical injury, a clinically-distinct and frequently compensation-seeking population, is not well established. This study determined the base rate of performance invalidity in a large electrical injury sample, and examined patient characteristics, injury parameters, and neuropsychological test performance based on validity status.Method: This cross-sectional study included data from 101 patients with electrical injury consecutively referred for post-acute neuropsychological evaluation. Eighty-five percent of the sample was compensation-seeking. Multiple performance validity tests (PVTs) were administered as part of standard clinical evaluation. For patients with four or more PVTs, valid performance was operationalized as less than or equal to one PVT failure and invalid performance as two or more failures.Results: Frequency analysis revealed 66% (n = 67) had valid performance while 29% (n = 29) demonstrated probable invalid performance; the remaining 5% (n = 5) had indeterminate validity. No significant differences in demographics or injury parameters emerged between validity groups (0 vs. 1 vs. ≥2 PVT failures). In contrast, the electrical injury group with invalid performance performed significantly worse across tests of processing speed and executive abilities than those with valid performance (ps< .05, ηp2 = .19-.25).Conclusions: The current study is the first to establish the base rate of neuropsychological performance invalidity in electrical injury survivors using empirical methods and current practice standards. Patient and clinical variables, including compensation-seeking status, did not differ between validity groups; however, neuropsychological test performance did, supporting the need for multi-method, objective performance validity assessment.

Examination of the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) validity and substantive scales in patients with electrical injury.

Objective: Electrical injury (EI) is a distinct subtype of traumatic injury that often results in a unique constellation of cognitive sequelae and unusual sensory experiences due to peripheral nervous system injury that are uncommon in general medical/neurological populations and have been unexplored with the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). Method: This study examined performance patterns on MMPI-2-RF validity and substantive scales among 62 EI patients who underwent neuropsychological evaluation, of which 46 demonstrated valid symptom reporting and neurocognitive test performance via multiple independent validity indicators and were retained for analysis. Results: Valid EI patients scored significantly higher than the MMPI-2-RF normative sample on several validity scales with the largest effect sizes on F-r (Infrequent Responses), Fs (Infrequent Somatic Responses), FBS-r (Symptom Validity), and RBS (Response Bias), and ≥33% obtaining elevated scores on these scales per standard interpretive criteria. Review of item content on these scales revealed several reflect disturbances in sensation, physical functioning, and/or cognition that are not infrequent in this population. Further, MMPI-2-RF clinical profiles did not reveal generalized distress or noncredible over-reporting. Rather, similar to the MMPI-2, valid EI patients had a specific pattern related to physical/sensory symptoms and reduced positive emotions with elevations on restructured clinical (RC) scale 1 (somatic complaints), somatic/cognitive specific problem scales, and low positive emotions (RC2). Conclusions: Elevations on some MMPI-2-RF validity scale may capture some degree of actual EI sequela that neuropsychologists need to consider to prevent erroneously concluding that a credible EI patient is over-reporting when s/he is reporting bona fide, EI-related symptoms.

Psychiatric Outcome Over a Decade After Electrical Injury: Depression as a Predictor of Long-Term Adjustment.

Electrical injury (EI) produces a variety of physical, cognitive, and emotional consequences. Psychiatric and neurocognitive symptoms may complicate survivors' psychosocial adjustment and ability to return to work. However, due to a paucity of longitudinal research, the long-term course of EI remains poorly understood. The purpose of this study was to investigate psychiatric and functional status in EI patients over a decade after injury. Fourteen EI patients who originally underwent baseline neuropsychological evaluation participated in this long-term follow-up. Participants completed a telephone survey of functional status, neuropsychological symptom checklist, and the Psychosocial Adjustment to Illness Scale Self-Report. Participants were grouped according to baseline Beck Depression Inventory (BDI) scores. After an average of 12.36 years postinjury, participants with elevated baseline BDI scores experienced difficulty across multiple domains of psychosocial adjustment at follow-up. This group was also less likely to return to work and exhibited a significant increase in psychological distress. EI results in significant chronic psychiatric complaints for many survivors. In the current sample, psychiatric sequelae of EI continue to persist over a decade after injury. Moreover, elevated baseline BDI scores predicted worse outcomes for vocational and psychosocial adjustment. Findings underscore the impact of emotional symptoms on recovery and need for specialized psychiatric intervention immediately following injury.

Mood and cognition after electrical injury: a follow-up study.

Individuals who have experienced an electrical injury have been reported to demonstrate both acute and delayed cognitive and psychiatric symptoms. The present study assessed 20 electrically injured patients who underwent neuropsychological evaluations twice following their injury. Time since injury, time between assessments, and longitudinal mood changes were evaluated for their potential impact on simple and complex attention outcomes. As an overall group, there was little change over time from low average to average baseline attention/concentration performance. However, results indicated that longitudinal increases in depressive symptoms were consistently associated with poorer performance on a measure of simple and complex attention. Loss of consciousness, litigation status, baseline injury status (acute vs. post-acute), and time between evaluations were not significant predictors of changes in cognitive performance. Implications for the treatment of comorbid psychiatric issues and for future research on victims of electrical trauma are discussed.

Alteration in functional brain systems after electrical injury.

Neuropsychological studies in electrical injury patients have reported deficits in attention, learning, and working memory, but the neural substrates of these deficits remain poorly characterized. In this study we sought to examine whether electrical injury subjects demonstrate abnormal patterns of brain activation during working memory and procedural learning tasks. Fourteen electrical injury subjects and fifteen demographically matched healthy control subjects performed a spatial working memory paradigm and a procedural learning paradigm during functional MRI studies. For the spatial working memory task, electrical injury patients exhibited significantly greater activation in the middle frontal gyrus and motor and posterior cingulate cortices. Increased activation in EI subjects also was observed on a visually-guided saccade task in several sensorimotor regions, including the frontal and parietal eye fields and striatum. On the procedural learning task, electrical injury patients exhibited significantly less activation in the middle frontal gyrus, anterior cingulate cortex, and frontal eye fields than controls. This is the first study to document task-dependent, system-level cortical and subcortical dysfunction in individuals who had experienced an electrical shock trauma.

Psychiatric morbidity following electrical injury and its effects on cognitive functioning.

OBJECTIVE: This study examines the prevalence of psychiatric morbidity in a large sample of electrical injury (EI) patients in three phases of recovery and its effects on cognitive functioning. METHODS: Eight-six self-referred EI patients received psychiatric and neuropsychological evaluations. Descriptive statistics were conducted to examine the prevalence of psychiatric morbidity. Polytomous logistic regression was used to identify predictors of psychiatric diagnosis. Between-subjects analysis of variances (ANOVA) was conducted to examine the effects of psychiatric morbidity on cognitive functioning. RESULTS: Seventy-eight percent of subjects warranted a psychiatric diagnosis. Long-term patients compared to acute patients were more likely to be diagnosed with two diagnoses than not having any diagnosis (OR=14.30, 95% CI 1.40-38.71). Patients with two diagnoses performed worse than both patients with a single or no diagnosis on all cognitive outcome measures (P<.05). Voltage level, chronic pain and litigation status did not predict psychiatric morbidity. CONCLUSIONS: Psychiatric difficulties commonly emerge and persist following EI. EI patients with psychiatric conditions exhibited poorer cognitive performance as compared to EI patients with no post-injury psychiatric difficulties. Health care professionals need to devote careful attention to psychiatric and cognitive status when treating survivors of EI.

Neuropsychological changes following electrical injury.

The clinical presentation of electrical injury commonly involves physical, cognitive, and emotional complaints. Neuropsychological studies, including case reports, have indicated that electrical injury (EI) survivors may experience a broad range of impaired neuropsychological functions, although this has not been clarified through controlled investigation. In this study, we describe the neuropsychological test findings in a series of 29 EI patients carefully screened and matched to a group of 29 demographically similar healthy electricians. Participants were matched by their estimated premorbid intellectual ability. Multivariate analysis of variance was used to assess group differences in the following neuropsychological domains: attention and mental speed, working memory, verbal memory, visual memory, and motor skills. EI patients performed significantly worse on composite measures of attention/mental speed and motor skills, which could not be explained by demographic differences, injury parameters, litigation status, or mood disturbance. Results suggest that cognitive changes do occur in patients suffering from electrical injury.

Neuropsychologic functioning and health status in systemic lupus erythematosus: does ethnicity matter?

BACKGROUND: Despite increased severity of lupus in blacks, including more frequent neuropsychiatric manifestations, there is sparse data on neuropsychologic function in black patients with lupus. METHODS: Neuropsychologic functioning and health-related variables were examined among blacks (n = 34) and whites (n = 14) fulfilling American College of Rheumatology criteria for systemic lupus erythematosus. RESULTS: Blacks and whites performed comparably on measures of verbal and visual memory, working memory, and motor speed after controlling for estimates of premorbid cognitive ability. Blacks trended towards poorer performance on specific attention/processing speed measures. Pain, fatigue, depression, anxiety, physical and emotional well-being were unrelated to ethnicity. Blacks exhibited a trend towards greater impairment of physical functioning. Ethnicity-related differences in overall damage, noncognitive neuropsychiatric manifestations, and prevalence of nephritis revealed greater severity among blacks. CONCLUSIONS: Initial differences in premorbid cognitive function possibly contribute to disparate clinical outcomes, including a greater proportion of blacks exhibiting subnormal neurocognitive performance. Blacks evidencing lower premorbid ability may be at greater vulnerability for poorer functional outcomes (eg, coping skills, medical compliance and employment) if they experience disease-related cognitive dysfunction.