Naomi Chaytor

The Ecological Validity of Neuropsychological Tests: A Review of the Literature on Everyday Cognitive Skills

Evaluating the ecological validity of neuropsychological tests has become an increasingly important topic over the past decade. In this paper, we provide a comprehensive review of the research on the ecological validity of neuropsychological tests, as it pertains to everyday cognitive skills. This review is presented in the context of several theoretical issues facing ecological validity research. Overall, the research suggests that many neuropsychological tests have a moderate level of ecological validity when predicting everyday cognitive functioning. The strongest relationships were noted when the outcome measure corresponded to the cognitive domain assessed by the neuropsychological tests. Several other factors that may moderate the degree of ecological validity established for neuropsychological tests are in need of further exploration. These factors include the effects of the population being tested, the approach utilized (verisimilitude vs. veridicality), the person completing the outcome measure (significant other vs. clinician), illness severity, and time from injury until evaluation. In addition, a standard measurement of outcome for each cognitive domain is greatly needed to allow for comparison across studies.

Cognitive impairment is not equal in patients with epileptic and psychogenic nonepileptic seizures.

Summary:  Purpose: Patients with psychogenic nonepileptic seizures (PNES) and those with epileptic seizures (ES) purportedly have roughly equal neurocognitive deficits. However, recent findings suggest that patients with somatoform disorders exhibit more variable effort on neurocognitive testing than do controls. We reexamined neurocognitive function in patients with ESs and PNES by using symptom validity testing to control for variability in effort.

PEARLS depression treatment for individuals with epilepsy: A randomized controlled trial

OBJECTIVE Depression is associated with higher rates of suicide and lower levels of functioning and quality of life in individuals with epilepsy. The objective of this randomized controlled trial was to determine the effectiveness of PEARLS, a home-based program for managing depression in adult individuals with epilepsy and clinically significant acute and chronic depression. METHODS Delivered by masters-level counselors, PEARLS is a collaborative care intervention consisting of problem solving treatment, behavioral activation, and psychiatric consultation. Patients were randomly assigned to the PEARLS intervention (N = 40) or usual care (N = 40), and assessed at baseline, 6 months, and 12 months. RESULTS Compared with patients who received usual care, patients assigned to the PEARLS intervention achieved lower depression severity (P<0.005) (Hopkins Symptoms Checklist-20) and lower suicidal ideation (P = 0.025) over 12 months. CONCLUSIONS The PEARLS program, a community-integrated, home-based treatment for depression, effectively reduces depressive symptoms in adults with epilepsy and comorbid depression.

Working memory and aging: A cross-sectional and longitudinal analysis using a self-ordered pointing task

Age-related declines in working memory performance have been associated with deficits in inhibition, strategy use, processing speed, and monitoring. In the current study, cross-sectional and longitudinal methodologies were used to investigate the relative contribution of these components to age-related changes in working memory. In Experiment 1, a sample of 140 younger and 140 older adults completed an abstract design version of the Self-Ordered Pointing Task modeled after Shimamura and Jurica (1994). Experiment 1 revealed that only processing speed and monitoring explained age differences in SOPT performance. Participants in Experiment 2 were 53 older adults who returned 4 years after the initial testing and 53 young adults. A task that assessed the ability to generate and monitor an internal series of responses as compared to an externally imposed series of responses was also administered. Experiment 2 replicated the key findings from Experiment 1 and provided some further evidence for age-related internal monitoring difficulties. Furthermore, the exploratory longitudinal analysis revealed that older age and lower intellectual abilities tended to be associated with poorer performance on the SOPT at Time 2.

Long-term outcomes from the PEARLS randomized trial for the treatment of depression in patients with epilepsy

Depression is associated with higher rates of suicide and lower quality of life in individuals with epilepsy. We previously published the 12-month outcome from our randomized clinical trial of PEARLS (Ciechanowski P, Chaytor N, Miller J, et al. Epilepsy Behav. Epub 5 July 2010). The purpose of this study was to determine the long-term effectiveness of PEARLS, a home-based collaborative care intervention consisting of problem-solving treatment, behavioral activation, and psychiatric consultation, in individuals with epilepsy. Patients were randomly assigned to PEARLS (N=40) or usual care (N=40), and assessed at baseline and 6, 12, and 18 months. Patients assigned to PEARLS achieved lower depression severity (P<0.05) (Hopkins Symptoms Checklist-20), lower suicidal ideation (P<0.02), and better emotional well being (QOLIE-31) (P<0.02) over 18 months, compared with patients given the usual care. The PEARLS program significantly reduces depressive symptoms in adults with epilepsy, and this effect is maintained for 18 months after baseline and for more than 1 year after completion of home visits.

Managing epilepsy well: Self-management needs assessment

Epilepsy self-management interventions have been investigated with respect to health care needs, medical adherence, depression, anxiety, employment, and sleep problems. Studies have been limited in terms of representative samples and inconsistent or restricted findings. The direct needs assessment of patients with epilepsy as a basis for program design has not been well used as an approach to improving program participation and outcomes. This study investigated the perceived medical and psychosocial problems of adults with epilepsy, as well as their preferences for self-management program design and delivery format. Results indicated a more psychosocially challenged subgroup of individuals with significant depressive and cognitive complaints. A self-management program that involves face-to-face individual or group meetings led by an epilepsy professional and trained peer leader for 60 minutes weekly was preferred. Six to eight sessions focused on diverse education sessions (e.g., managing disability and medical care, socializing on a budget, and leading a healthy lifestyle) and emotional coping strategies delivered on weeknights or Saturday afternoons were most highly endorsed. Emotional self-management and cognitive compensatory strategies require special emphasis given the challenges of a large subgroup.

Risk Factors Associated With Severe Hypoglycemia in Older Adults With Type 1 Diabetes

OBJECTIVE Severe hypoglycemia is common in older adults with long-standing type 1 diabetes, but little is known about factors associated with its occurrence. RESEARCH DESIGN AND METHODS A case-control study was conducted at 18 diabetes centers in the T1D Exchange Clinic Network. Participants were ≥60 years old with type 1 diabetes for ≥20 years. Case subjects (n = 101) had at least one severe hypoglycemic event in the prior 12 months. Control subjects (n = 100), frequency-matched to case subjects by age, had no severe hypoglycemia in the prior 3 years. Data were analyzed for cognitive and functional abilities, social support, depression, hypoglycemia unawareness, various aspects of diabetes management, C-peptide level, glycated hemoglobin level, and blinded continuous glucose monitoring (CGM) metrics. RESULTS Glycated hemoglobin (mean 7.8% vs. 7.7%) and CGM-measured mean glucose (175 vs. 175 mg/dL) were similar between case and control subjects. More case than control subjects had hypoglycemia unawareness: only 11% of case subjects compared with 43% of control subjects reported always having symptoms associated with low blood glucose levels (P < 0.001). Case subjects had greater glucose variability than control subjects (P = 0.008) and experienced CGM glucose levels <60 mg/dL for ≥20 min on 46% of days compared with 33% of days in control subjects (P = 0.10). On certain cognitive tests, case subjects scored worse than control subjects. CONCLUSIONS In older adults with long-standing type 1 diabetes, greater hypoglycemia unawareness and glucose variability are associated with an increased risk of severe hypoglycemia. A study to assess interventions to prevent severe hypoglycemia in high-risk individuals is needed.

Sociodemographic and clinical factors associated with depression in epilepsy

The impact of mood disorders on patients with epilepsy is an important and growing area of research. If clinicians are adept at recognizing which patients with epilepsy are at risk for mood disorders, treatment can be facilitated and morbidity avoided. We completed a case-control study (80 depressed subjects, 141 nondepressed subjects) to determine the sociodemographic and clinical factors associated with self-reported depression in people with epilepsy. The Patient Health Questionnaire-9 was used to determine clinically significant depression. In multivariate analyses, depressed subjects with epilepsy were significantly less likely than nondepressed subjects to be married or employed and more likely to report comorbid medical problems and active seizures in the past 6 months. Adjusted for all other variables, subjects with epilepsy reporting lamotrigine use were significantly less likely to be depressed (OR=0.4, 95% CI: 0.2-0.8) compared with those not reporting lamotrigine use.

The Personality Assessment Inventory as a tool for diagnosing psychogenic nonepileptic seizures

Using 184 subjects with valid personality assessment interview (PAI) profiles and video–electroencephalography (VEEG)–confirmed diagnoses of epileptic seizures (ES; n = 109) or psychogenic nonepileptic seizures (PNES; n = 75), we present the diagnostic test performance of the PAI PNES Indicator and other PAI scales when used to differentiate PNES from ES. Subjects with PNES reported significantly higher somatic, conversion, depressed, anxious, and suicidal symptoms. As a diagnostic tool, the PNES Indicator does not add additional accuracy beyond the conversion subscale (SOM‐C). The somatization (SOM‐S) and physiological depression (DEP‐P) subscales perform as well as the SOM‐C subscale. The SOM‐C scale (cut point ≥70) was 58.7% sensitive and 83.5% specific at diagnosing PNES. Assuming a 30% prevalence of PNES, the SOM‐C scale has a positive predictive value (PPV) of 60.4% and negative predictive value (NPV) of 82.5%. Overall, the PAI SOM‐C subscale does not appear more accurate than other psychometric tests used to differentiate PNES from ES.

Fractionation of the dysexecutive syndrome in a heterogeneous neurological sample: Comparing the Dysexecutive Questionnaire and the Brock Adaptive Functioning Questionnaire

Primary objective: Research on the ecological validity of neuropsychological tests of executive functioning has been limited by disagreement in the number and make-up of the factors underlying the dysexecutive syndrome. The current study sought to determine whether similar components of everyday executive dysfunction are being measured by the Dysexecutive Questionnaire (DEX) and the Brock Adaptive Functioning Questionnaire (BAFQ). Research design: Using the same sample, a factor analysis of the DEX and the BAFQ was conducted to determine whether a similar underlying factor structure for the dysexecutive syndrome would be found across measures. Methods and procedures: The significant others of 46 adults with varying neurological conditions completed the DEX and BAFQ. Main outcomes and results: Behavioural inhibition, goal-directed behaviour/intentionality and executive memory/cognition were found to be key underlying factors of the everyday dysexecutive syndrome identified by both measures. The remaining factors were divergent. Conclusions: Consistent with prior research, this study indicates that the dysexecutive syndrome is multi-factorial. This research further highlights core factors associated with real world executive functioning deficits and demonstrates that the dysexecutive syndrome has distinct sub-components that transcend the specific questionnaire measure used.