The Utility of the Repeatable Battery of Neuropsychological Status in Patients with Temporal and Non-temporal Lobe Epilepsy.

OBJECTIVE: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a brief neuropsychological battery that has been validated in the assessment of dementia and other clinical populations. The current study examines the utility of the RBANS in patients with epilepsy. METHODS: Ninety-eight patients with epilepsy completed the RBANS as part of a more comprehensive neuropsychological evaluation. Performance on the RBANS was evaluated for patients with a diagnosis of temporal lobe epilepsy (TLE; n = 51) and other epilepsy patients (non-TLE, n = 47) in comparison to published norms. Multivariate analysis of variance compared group performances on RBANS indices. Rates of impairment were also compared across groups using cutoff scores of ≤1.0 and ≤1.5 standard deviations below the normative mean. Exploratory hierarchical regressions were used to examine the relations between epilepsy severity factors (i.e., age of onset, disease duration, and number of antiepileptic drugs [AEDs]) and RBANS performance. RESULTS: TLE and non-TLE patients performed below the normative sample across all RBANS indices. Those with TLE performed worse than non-TLE patients on the Immediate and Delayed Memory indices and exhibited higher rates of general cognitive impairment. Number of AEDs was the only epilepsy severity factor that significantly predicted RBANS total performance, accounting for 14% of the variance. CONCLUSIONS: These findings suggest that the RBANS has utility in evaluating cognition in patients with epilepsy and can differentiate TLE and non-TLE patients. Additionally, number of AEDs appears to be associated with global cognitive performance in adults with epilepsy.

Neuropsychological correlates of subjective fatigue in non-demented older adults and the moderating effect of physical activity.

This study examined the association between self-reported fatigue and neuropsychological performance in 167 middle-aged and older (age range: 50-91 years) adults without dementia. Participants completed the Fatigue Symptom Inventory, a comprehensive neuropsychological evaluation, and frailty assessment. Higher levels of fatigue were significantly associated with poorer attention/information processing, executive functioning, and psychomotor speed, even after controlling for depression, sleep quality, physical weakness, and other covariates. Participants endorsing moderate-severe fatigue faced higher odds (OR = 6.6, 95% CI = 1.1, 39.1) of exhibiting clinical attention/information processing impairments than those without. Moderation analyses showed that fatigue was related to select cognitive deficits among those reporting mean or lower levels of activity, but not high levels. These findings highlight fatigue as an important clinical marker of select cognitive deficits in non-demented older adults that is distinct from the common confounding conditions examined in this study. High levels of physical activity may buffer this relationship.

Sleep quality mediates the relationship between frailty and cognitive dysfunction in non-demented middle aged to older adults.

ABSTRACTObjectives:Frailty is associated with cognitive decline in older adults. However, the mechanisms explaining this relationship are poorly understood. We hypothesized that sleep quality may mediate the relationship between frailty and cognition. PARTICIPANTS: 154 participants aged between 50-90 years (mean = 69.1 years, SD = 9.2 years) from the McKnight Brain Registry were included. MEASUREMENTS: Participants underwent a full neuropsychological evaluation, frailty and subjective sleep quality assessments. Direct relationships between frailty and cognitive function were assessed using linear regression models. Statistical mediation of these relationships by sleep quality was assessed using nonparametric bootstrapping procedures. RESULTS: Frailty severity predicted weaker executive function (B = -2.77, ß = -0.30, 95% CI = -4.05 - -1.29) and processing speed (B = -1.57, ß = -0.17, 95% CI = -3.10 - -0.16). Poor sleep quality predicted poorer executive function (B = -0.47, ß = -0.21, 95% CI = -0.79 - -0.08), processing speed (B = -0.64, ß = -0.28, 95% CI = -0.98 - -0.31), learning (B = -0.42, ß = -0.19, 95% CI = -0.76 - -0.05) and delayed recall (B = -0.41, ß = -0.16, 95% CI = -0.80 - -0.31). Poor sleep quality mediated the relationships between frailty severity and executive function (B = -0.66, ß = -0.07, 95% CI = -1.48 - -0.39), learning (B = -0.85, ß = -0.07, 95% CI = -1.85 - -0.12), delayed recall (B = -0.47, ß = -0.08, 95% CI = -2.12 - -0.39) and processing speed (B = -0.90, ß = -0.09, 95% CI = -1.85 - -0.20). CONCLUSIONS: Relationships between frailty severity and several cognitive outcomes were significantly mediated by poor sleep quality. Interventions to improve sleep quality may be promising avenues to prevent cognitive decline in frail older adults.

Reliable Digit Span: Does it Adequately Measure Suboptimal Effort in an Adult Epilepsy Population?

OBJECTIVE: Assessment of performance validity is a necessary component of any neuropsychological evaluation. Prior research has shown that cutoff scores of ≤6 or ≤7 on Reliable Digit Span (RDS) can detect suboptimal effort across numerous adult clinical populations; however, these scores have not been validated for that purpose in an adult epilepsy population. This investigation aims to determine whether these previously established RDS cutoff scores could detect suboptimal effort in adults with epilepsy. METHOD: Sixty-three clinically referred adults with a diagnosis of epilepsy or suspected seizures were administered the Digit Span subtest of the Wechsler Adult Intelligence Scale (WAIS-III or WAIS-IV). Most participants (98%) passed Trial 2 of the Test of Memory Malingering (TOMM), achieving a score of ≥45. RESULTS: Previously established cutoff scores of ≤6 and ≤7 on RDS yielded a specificity rate of 85% and 77% respectively. Findings also revealed that RDS scores were positively related to attention and intellectual functioning. Given the less than ideal specificity rate associated with each of these cutoff scores, together with their strong association to cognitive factors, secondary analyses were conducted to identify more optimal cutoff scores. Preliminary results suggest that an RDS cutoff score of ≤4 may be more appropriate in a clinically referred adult epilepsy population with a low average IQ or lower. CONCLUSIONS: Preliminary findings indicate that cutoff scores of ≤6 and ≤7 on RDS are not appropriate in adults with epilepsy, especially in individuals with low average IQ or below.