Epilepsy in classic Rett syndrome: Course and characteristics in adult age

Rett syndrome (RTT) is a neurodevelopmental disorder that almost exclusively affects females. Epilepsy is a major clinical feature, but its long-term course in RTT has not been sufficiently explored. This study addresses the development of the epilepsy in adults with RTT.

Available females diagnosed with RTT in Norway were asked to participate. Parents/caregivers were interviewed, the girls/women were examined and their medical records reviewed. Participants were categorized according to age, epilepsy, seizure patterns and mutation severity groups. RTT severity was assessed (epilepsy score excluded).

70 females with classic RTT were included. A presumed pathogenic mutation in MECP2 was found in 96%. The presence of active epilepsy (seizures last five years) was similar in all age groups above the age of ten: 11 (65%) in adolescents (11-20 years), 9 (60%) in young adults (21-30 years) and 14 (67%) in participants above 30 years of age. Tonic-clonic seizures within the last year were present in 55, 67 and 64%, and ≥ weekly seizures occurred in 27, 45 and 50% in the respective age groups. Among participants with active epilepsy, 69% had unremitting seizures, whereas 31% had experienced remissions for more than six months during the last five years. In the oldest group (>30 years), only 19% had obtained seizure control for >5 years, and 14% had never experienced seizures. Seizure activity correlated with RTT severity score, whereas the relationship to mutation type remained ambiguous.

Epilepsy continues to be a major concern in adults with RTT. Two thirds of women above 30 years of age remained with active epilepsy and 50% of them had seizures at least weekly.