Developmental outcomes of childhood-onset temporal lobe epilepsy: a community-based study

To assess the impact of childhood-onset temporal lobe epilepsy (TLE) on the attainment of normative developmental tasks and identify predictors of long-term developmental outcomes.

In 1992-1993, a prospective longitudinal cohort study of childhood-onset TLE was commenced in the State of Victoria, Australia. At review in 2004-2006, we assessed developmental tasks, which are age-specific individual psychosocial achievements tied to particular phases of the lifespan. The cohort comprised 54 individuals (33 female) with a mean age of 20 years (range 12-29), and mean age at TLE onset of 6 years (range 0.2-15).

Individuals were clustered into three groups representing distinct developmental trajectories: (1) a Normal group (52%) who achieved most of their developmental tasks, (2) an Altered group (37%) who achieved some, and (3) a Delayed group (11%) who achieved few. The groups showed significant cognitive differences, with the Normal group outperforming the Altered and Delayed groups on a range of measures (p < 0.05). Multiple discriminant function analysis indicated that membership of the groups was independently predicted by the chronicity of seizures, cognitive functioning, having surgically remediable epilepsy, and gender (p < 0.001). Seizure chronicity and cognition discriminated between all three trajectories, while surgical intervention and gender primarily discriminated between the Altered and Delayed trajectories.

Childhood-onset TLE can disrupt achievement of normative developmental tasks that is independently predicted by medical, biologic, and cognitive factors. Assessment of developmental tasks across the lifespan provides a practical framework for guiding prognostic counseling of patients and families.