Apathy in people with epilepsy and its clinical significance: A case-control study

Purpose Apathy as a state of decreased motivation has not been highlighted in people with epilepsy (PWE). We investigated its clinical significance in PWE. Methods We invited adult PWE who had been administered antiepileptic drugs (AEDs) for at least 1 year and compared them with age- and gender-matched healthy controls. Eligible participants completed several questionnaires including the Apathy Evaluation Scale-Self (AES-S), the Korean version of the Neurological Disorders Depression Inventory for Epilepsy (K-NDDI-E), the Generalized Anxiety Disorder-7 (GAD-7), the Epworth Sleepiness Scale (ESS), and the Insomnia Severity Index (ISI), and the Quality of Life in Epilepsy-10 (QOLIE-10). We investigated the degree of interictal apathy in PWE compared with controls and identified its predictors. We also measured the impact of apathy on patients’ QOL. Results The mean overall AES-S score in PWE was similar to that of controls. However, the score was significantly higher in patients with uncontrolled epilepsy than controls (p < 0.01). Among subscale scores of the AES-S, the mean behavioral score was significantly higher in PWE than controls (p < 0.01). Education level, employment, household income, disease duration, AED-related factors, seizure control, and scores of the K-NDDI-E, GAD-7, ESS, and ISI were associated with the overall AES-S score by univariate analyses. However, major predictors were the K-NDDI-E (β = 0.476, p < 0.001) and duration of AED intake (β = 0.151, p < 0.01). The degree of apathy was significantly higher in patients receiving AEDs for 20 years or more than those receiving AEDs for 1–9 years (p < 0.01). The overall AES-S score was inversely correlated with the overall QOLIE-10 score (p < 0.001). Conclusion Duration of AED intake in PWE seems to be a critical factor for apathy regardless of comorbid depression.