Effect of invasive EEG monitoring on cognitive outcome after left temporal lobe epilepsy surgery

OBJECTIVES

The objective of this cohort study was to compare neuropsychological outcomes following left temporal lobe resection (TLR) in patients with epilepsy who had or had not undergone prior invasive monitoring.

METHODS

Data were obtained from an institutional review board-approved, neuropsychology registry for patients who underwent epilepsy surgery at Cleveland Clinic between 1997 and 2013. A total of 176 patients (45 with and 131 without invasive EEG) met inclusion criteria. Primary outcome measures were verbal memory and language scores. Other cognitive outcomes were also examined. Outcomes were assessed using difference in scores from before to after surgery and by presence/absence of clinically meaningful decline using reliable change indices (RCIs). Effect of invasive EEG on cognitive outcomes was estimated using weighting and propensity score adjustment to account for differences in baseline characteristics. Linear and logistic regression models compared surgical groups on all cognitive outcomes.

RESULTS

Patients with invasive monitoring showed greater declines in confrontation naming; however, when RCIs were used to assess clinically meaningful change, there was no significant treatment effect on naming performance. No difference in verbal memory was observed, regardless of how the outcome was measured. In secondary outcomes, patients with invasive monitoring showed greater declines in working memory, which were no longer apparent using RCIs to define change. There were no outcome differences on other cognitive measures.

CONCLUSIONS

Results suggest that invasive EEG monitoring conducted prior to left TLR is not associated with greater cognitive morbidity than left TLR alone. This information is important when counseling patients regarding cognitive risks associated with this elective surgery.

Reliable change indices and standardized regression-based change score norms for evaluating neuropsychological change in children with epilepsy

Reliable change indices (RCIs) and standardized regression-based (SRB) change score norms permit evaluation of meaningful changes in test scores following treatment interventions, like epilepsy surgery, while accounting for test-retest reliability, practice effects, score fluctuations due to error, and relevant clinical and demographic factors. Although these methods are frequently used to assess cognitive change after epilepsy surgery in adults, they have not been widely applied to examine cognitive change in children with epilepsy. The goal of the current study was to develop RCIs and SRB change score norms for use in children with epilepsy. Sixty-three children with epilepsy (age range: 6-16; M=10.19, SD=2.58) underwent comprehensive neuropsychological evaluations at two time points an average of 12 months apart. Practice effect-adjusted RCIs and SRB change score norms were calculated for all cognitive measures in the battery. Practice effects were quite variable across the neuropsychological measures, with the greatest differences observed among older children, particularly on the Children's Memory Scale and Wisconsin Card Sorting Test. There was also notable variability in test-retest reliabilities across measures in the battery, with coefficients ranging from 0.14 to 0.92. Reliable change indices and SRB change score norms for use in assessing meaningful cognitive change in children following epilepsy surgery are provided for measures with reliability coefficients above 0.50. This is the first study to provide RCIs and SRB change score norms for a comprehensive neuropsychological battery based on a large sample of children with epilepsy. Tables to aid in evaluating cognitive changes in children who have undergone epilepsy surgery are provided for clinical use. An Excel sheet to perform all relevant calculations is also available to interested clinicians or researchers.

The effects of training on the ability of adults with an intellectual disability to give informed consent to medication

BACKGROUND

This study had two aims: to investigate the capacity of individuals with intellectual disabilities (ID) to make decisions about their medications, and to evaluate whether the provision of training (information) sessions on medications would increase their capacity.

METHOD

Twenty-eight adults (18 male and 10 female), with a mild to moderate ID were included in this study and they were taking either Epilim, Metformin or Haloperidol medications. The participants were split into groups that comprised of participants taking the same medications. Each of the groups received three training sessions on their own medications. Capacity to consent was measured by the Adapted - Assessment of Capacity Questionnaire (A-ACQ), which was specially adapted for each medication type from the original measure (ACQ). Receptive language ability was measured by the British Picture Vocabulary Scale-II (BPVS-II).

RESULTS

A two-factor mixed anova analysis indicated that the provision of training had improved the capacity of the participants to give informed consent to taking their medications. Analysis using Pearson's correlations indicated that increased levels of receptive language ability correlated with greater ability to give informed consent to taking medication.

CONCLUSIONS

The provision of information that is formatted in a way that individuals with ID can understand may be a useful way to increase knowledge on medications. Further research that investigates the provision of information with larger samples is warranted.

Training distress and performance readiness: laboratory and field validation of a brief self-report measure

Three studies were conducted to validate the Training Distress Scale (TDS), a 19-item measure of training-related distress and performance readiness. Study 1 was a randomized, controlled laboratory experiment in which a treatment group undertook daily interval training until a 25% decrement occurred in time-to-fatigue performance. Comparisons with a control group showed that TDS scores increased over time within the treatment group but not in the control group. Study 2 was a randomized, controlled field investigation in which performance capabilities and TDS responses were compared across a high-intensity interval training group and a control group that continued normal training. Running performance decreased significantly in the training group but not in the control group, and scores on the TDS mirrored those changes in performance capabilities. Study 3 examined the relationship between TDS scores obtained over a 2-week period before major swimming competitions and subsequent performance in those competitions. Significantly, better performance was observed for swimmers with low TDS scores compared with those with moderate or high TDS scores. These findings provide both laboratory and field evidence for the validity of the TDS as a measure of short-term training distress and performance readiness.

Memory performance in older adults before and after temporal lobectomy for pharmacoresistant epilepsy

Little is known about the effects of epilepsy surgery on memory in older adults. The purpose of this study was to determine if older adults exhibit greater memory decline than younger adults after anterior temporal lobectomy (ATL). Patients 55 years and older at time of surgery (23 left, 14 right ATL, range 55-66 years) were compared to patients age 25-35 years (44 left, 33 right ATL) to assess differences in preoperative to postoperative change in WMS-III index scores. Repeated-measures ANOVAs and ANCOVAs revealed that older patients did not demonstrate greater decline than younger patients across any of the memory indices. Rather, in the left ATL group, older patients showed less decline than younger patients on the Auditory Delayed Memory Index. Similarly, in the right ATL group, older patients showed less decline than younger patients on the Visual Delayed Memory Index. These patterns were also apparent in frequency of individual change. Results provide preliminary evidence that older adults who are good candidates for ATL are not at greater risk for memory decline when measured at 7 months postoperatively.