Beyond depression: The impact of executive functioning on quality of life in patients with temporal lobe epilepsy

Abstract

Objective: Individuals with temporal lobe epilepsy (TLE) often experience diminished quality of life (QoL). Although comorbid depression is one of the most recognized predictors of poor QoL in TLE, impairments in verbal memory (VM) and executive functioning (EF), have also been identified as risk factors, independent of other biological and psychosocial factors. In this study, we examine the contribution of depression, VM, and EF to QoL in 52 well-characterized medically-refractory TLE patients. Methods: Quality of life was assessed with the Quality of Life in Epilepsy (QOLIE-31) questionnaire and depression symptomatology was evaluated with the Beck Depression Inventory-II (BDI-II). Tests of VM included the California Verbal Learning Test-Second Edition and the Wechsler Memory Scale-Third Edition, Logical Memory and Verbal Paired Associates subtests. Tests of EF included the D-KEFS Category Switching and Color Word Interference Tests, and the Trail Making Test. Using these measures, a principal component (PC) was derived for VM and for EF. Hierarchical multiple linear regression analysis was used to evaluate the unique contributions of BDI-II Score, VM PC, and EF PC to the QOLIE-31 Total Score, while controlling for important clinical and demographic variables. Post-hoc analyses were also performed to examine the contribution of each variable to specific QOLIE subscales. Results: Of the clinical variables, only number of antiepileptic drugs contributed to QOLIE scores. As expected, severity of depressive symptoms was the most significant predictor of QOLIE Total Score, explaining 43.4% of the variance in total QoL. The VM PC did not contribute to the QOLIE Total Score. Rather, our EF PC emerged as an important predictor of QoL, explaining an additional 5% of the variance, after controlling for clinical variables, depression severity, and VM performance. Significance: These findings suggest that a combination of clinical, affective, and cognitive factors influence QoL in patients with TLE. Designing interventions with careful attention to depression and EF may be needed to optimize QoL in patients with refractory TLE and potentially other epilepsy syndromes.

Predicting mood decline following temporal lobe epilepsy surgery in adults

“…Executive function measures were included in variable selection because neuropsychological studies in major depressive disorder (MDD) have reported executive functioning deficits, and executive dysfunction has been shown to affect the quality of life of patients with TLE, even when controlling for psychiatric comorbidities. 28,35 However, our study shows the inverse relationship; patients who perform better on the verbal fluency test preoperatively are more likely to develop postoperative depression. In our sample, patients who had declines in verbal fluency postoperatively were marginally more likely to experience mood decline that those who did not have verbal fluency worsening.…”

“…The verbal fluency test requires patients to name as many words as they can that begin with each of three letters (F‐A‐S) within a given time frame. Executive function measures were included in variable selection because neuropsychological studies in major depressive disorder (MDD) have reported executive functioning deficits, and executive dysfunction has been shown to affect the quality of life of patients with TLE, even when controlling for psychiatric comorbidities 28,35 . However, our study shows the inverse relationship; patients who perform better on the verbal fluency test preoperatively are more likely to develop postoperative depression.…”

Symptoms of depression can be more frequent in non-surgical patients with left lateralization of Temporal Lobe Epilepsy: A systematic review

“…1). Of all the performed studies, only four were multicenter [15, 19–21], all the others were single center and cross-sectional.…”

Does psychiatric comorbidity influences quality of life and disability among subjects with refractory focal epilepsy- a comparative cross-sectional study

“…A study from the USA of refractory focal epilepsy subjects showed that depression had poorer health perception and reported lower QOL in various domains. 27 In another study, common mental disorders significantly affecting disability were PTSD, MDD, Psychosis(BPAD) and GAD. 28 Schizophrenia and affective psychosis had the highest degree of disability; young age of onset, poor medication adherence and failure of symptom remission as strong predictors of disability.…”