Abstracts

Understanding the factors that contribute to quality of life (QoL) is essential for designing meaningful, patient-centred interventions for individuals with developmental and epileptic encephalopathies (DEEs). To identify key predictors of QoL without imposing prior assumptions, we employed a hypothesis-free regression tree analysis, allowing for data-driven exploration of variables most strongly associated with QoL outcomes across multiple domains.

A questionnaire was completed by 242 caregivers of individuals with DEEs (74%) and other severe neurodevelopmental encephalopathies ≥2 years of age. QoL was measured using the Quality of Life Inventory-Disability (QI-D). Independent variables described health, functional abilities and daily activities. The R package rpart was used to build the regression trees to explore the most influential factors associated with QoL.

Median age was 8.8y (interquartile range 4.6-14.9y); however, developmental age as measured by the Developmental Profile, Fourth Edition (DP-4) fell below a 12-month level across domains. Mean total QI-D score was 60.2+14.1 out of a total possible score of 100. The subgroup with the lowest QoL scores comprised individuals with low (raw score < 4; age-equivalent of 4-5 months) cognition scores measured with the DP-4 (n=52, mean score 46.4) whereas higher QoL scores were achieved by individuals with higher cognition scores and capacity to engage actively when using a touchscreen (n=123, mean score 67.5; Figure 1). Notably, small differences in DP-4 Cognition scores representing foundational cognitive capacities like alertness and responsiveness to the environment were associated with steep increases in QoL (Figure 2).