Predicting mood decline following temporal lobe epilepsy surgery in adults.

OBJECTIVE: To develop a model to predict the probability of mood decline in adults following temporal lobe resection for the treatment of pharmacoresistant epilepsy. METHODS: Variable selection was performed on 492 patients from the Cleveland Clinic using best subsets regression. After completing variable selection, a subset of variables was requested from four epilepsy surgery centers across North America (n = 100). All data were combined to develop a final model to predict postoperative mood decline (N = 592). Internal validation with bootstrap resampling was performed. A clinically significant increase in depressive symptoms was defined as a 15% increase in Beck Depression Inventory-Second Edition score and a postoperative raw score > 11. RESULTS: Fourteen percent of patients in the Cleveland Clinic cohort and 22% of patients in the external cohort experienced clinically significant increases in depressive symptoms following surgery. The final prediction model included six predictor variables: psychiatric history, resection side, relationship status, verbal fluency score, age at preoperative testing, and presence/absence of malformation of cortical development on magnetic resonance imaging. The model had an optimism-adjusted c-statistic of .70 and good calibration, with slight probability overestimation in higher risk patients. SIGNIFICANCE: Clinicians can utilize our nomogram via a paper tool or online calculator to estimate the risk of postoperative mood decline for individual patients prior to temporal lobe epilepsy surgery.

The comparative effectiveness of electroencephalographic indices in predicting response to escitalopram therapy in depression: A pilot study.

BACKGROUND: This study aims to compare the effectiveness of EEG frequency band activity including interhemispheric asymmetry and prefrontal theta cordance in predicting response to escitalopram therapy at 8-weeks post-treatment, in a multi-site initiative. METHODS: Resting state 64-channel EEG data were recorded from 44 patients with a diagnosis of major depressive disorder (MDD) as part of a larger, multisite discovery study of biomarkers in antidepressant treatment response, conducted by the Canadian Biomarker Integration Network in Depression (CAN-BIND). Clinical response was measured at 8-weeks post-treatment as change from baseline Montgomery-Asberg Depression Rating Scale (MADRS) score of 50% or more. EEG measures were analyzed at (1) pre-treatment baseline (2) 2 weeks post-treatment and (3) as an ''early change" variable defined as change in EEG from baseline to 2 weeks post-treatment. RESULTS: At baseline, treatment responders showed elevated absolute alpha power in the left hemisphere while non-responders showed the opposite. Responders further exhibited a cortical asymmetry in the parietal region. Groups also differed in pre-treatment relative delta power with responders showing greater power in the right hemisphere over the left while non-responders showed the opposite. At 2 weeks post-treatment, responders exhibited greater absolute beta power in the left hemisphere relative to the right and the opposite was noted for non-responders. A reverse pattern was noted for absolute and relative delta power at 2 weeks post-treatment. Responders exhibited early reductions in relative alpha power and early increments in relative theta power. Non-responders showed a significant early increase in prefrontal theta cordance. CONCLUSIONS: Hemispheric asymmetries in the alpha and delta bands at baseline and at 2 weeks post-treatment have moderately strong predictive utility in predicting response to antidepressant treatment.

Developmental patterns in priming and familiarity in explicit recollection.

Developmental trajectories of two classes of human memory, implicit and explicit memory, appear to diverge. We examined how developmental differences in perceptual and conceptual priming, two types of implicit memory, coincide with differences between familiarity and recollective responses on explicit memory tests that employ the Remember/Know paradigm ( Tulving, 1985 ). Both types of priming were characterized by developmental invariance in 52 children and adolescents ages 8-19 years. Contrary to Komatsu, Naito, and Fuke (1996) results, few age-group differences in perceptual priming were observed following a levels-of-processing encoding manipulation. In contrast, age group differences were found for "Remember" but not "Know" responses. Neither levels of awareness nor strategies influenced priming. Adult levels of performance appear earlier in development on perceptual and conceptual priming tests compared to explicit memory tests. Similar developmental dissociations exist between explicit and implicit memory performance as between "Remember" and "Know" recollective responses.

Cognitive effects of long-term benzodiazepine use in older adults.

This study examined the potential for cognitive morbidity associated with the long-term use of benzodiazepine (BZ) sedative-hypnotics in a sample of healthy older adults. Tests of memory, attention and processing speed were conducted prior to and 1 month after drug discontinuation for 25 BZ-users and at similar intervals for 26 healthy control subjects. After controlling for differences in affective status between BZ-users and controls, there were no significant group differences in cognitive performance. However, BZ-users showed greater gains on tests of attention and speed of processing at repeat testing compared with controls this improvement was not attributable to a change in affective status. These findings suggest that there may be subtle and reversible effects of long-term BZ use on speed-dependent tasks in older adults. However, the magnitude of these effects is quite small and may be of little clinical significance in the healthy elderly.