A multicenter, matched case-control analysis comparing burden-of-illness in Dravet syndrome to refractory epilepsy and seizure remission in patients and caregivers in Germany

Abstract

Objective: To compare direct and indirect costs and quality of life (QoL) of pediatric and adult patients with Dravet syndrome (DS), with drug-resistant epilepsy (DRE) and in seizure remission (SR), and their caregivers, in Germany. Methods: Questionnaire responses from 93 DS patients and their caregivers were matched by age and gender with responses from 93 DRE and 93 SR patients collected in independent studies, and were compared across main components of QoL, direct costs (patient visits, medication use, care level, medical equipment, and ancillary treatments), and indirect costs (quitting job, reduced working hours, missed days). Results: Mean total direct costs were highest for DS patients (€4864 [median €3564] vs €3049 [median €1506] for DRE [excluding outliers], P = 0.01; and €1007 [median €311], P < 0.001 for SR). Total lost productivity over 3 months was highest among caregivers of pediatric DS (€4757, median €2841), compared with those of DRE (€1541, P < 0.001; median €0) and SR patients (€891, P < 0.001; median €0). The proportions of caregivers in employment were similar across groups (62% DS, 63% DRE, and 63% SR) but DS caregivers were more likely to experience changes to their working situation, such as quitting their job (40% DS vs 16% DRE and 9% SR, P < 0.001 in both comparisons). KINDL scores were significantly lower for DS patients (62 vs 74 and 72, P < 0.001 in both comparisons), and lower than for the average German population (77). Pediatric caregiver EQ-5D scores across all cohorts were comparable with population norms, but more DS caregivers experienced moderate to severe depressive symptoms (24% vs 11% and 5%). Mean Beck Depression Inventory (BDI-II) score was significantly higher in DS caregivers than either of the other groups (P < 0.001). Significance: This first comparative study of Dravet syndrome to difficult-to-treat epilepsy and to epilepsy patients in seizure remission emphasizes the excess burden of DS in components of QoL and direct costs. The caregivers of DS patients have a greater impairment of their working lives (indirect costs) and increased depression symptoms.