Abstracts

Rationale: Childhood epilepsy has a significant impact on the family’s QOL. The Impact of Epilepsy Scale (IPES) is a brief (11 questions), validated, global instrument that specifically measures this issue. No QOL scale for children with epilepsy is known to be responsive or sensitive to changes in epilepsy severity over time. We assessed the responsiveness of the IPES in a cohort of children with epilepsy over 3 years and hypothesized that the impact of childhood epilepsy on the child and family would change in the same direction as seizure frequency/severity. Methods: The original assessment of the psychometric validity of the IPES included 97 families with children at various stages of epilepsy control. Of these 63 (65%) participated in the present longitudinal study. The children (25 boys) had a variety of epilepsy syndromes. Families completed the IPES at baseline (T1) and again 3 years later (T2). The child’s epilepsy frequency/severity was compared at T1 and T2 with a standardized physician-completed questionnaire that yielded 3 simple categories of seizure severity: none, low and high, depending on frequency and seizure type. Changes in IPES scores were then compared with seizure frequency/severity using standard statistical techniques including MANCOVA. Results: Mean age at T1 was 10 years (range 2-17) and mean interval between T1 and T2 was 33 months (20-44). At T1 and T2, 66% had no behavioral diagnosis, 79% were of normal intelligence and 94% had no co-morbid neurological diagnosis. Between T1 and T2, seizure severity improved in 49%, was unchanged in 33% and deteriorated in 18%. 51% of patients had been seizure-free for a year at T2. When all patients were considered, the total IPES scores worsened over time; however, there was a statistically significant close relationship with changes in seizure severity (MANCOVA) – those with improved seizure severity had improved IPES, those with deteriorating seizure severity had worse IPES and those with no change in seizure severity had no change in IPES (p<0.001). All 11 items in the IPES contributed to its responsiveness over time to epilepsy severity (MANCOVA). On univariate analysis with Bonferroni adjustment 4 items were particularly statistically significant (p<0.0045) (overall health, number of activities, academic success and loss of original hopes for child). Conclusions: The IPES is responsive over time to changes in the severity of childhood epilepsy and is a valid instrument to study the effects of longitudinal treatment. Because of its brevity (2-3 minutes to complete) and statistical robustness, it could be considered for use in clinical settings for individual patients to highlight areas of concern.