Long-term cognitive outcomes in tuberous sclerosis complex.
Charlotte Tye, Fiona S Mcewen, Holan Liang and 6 others
PMID 31538337WHAT IT FOUND
Seizures in the first two years, especially non-spasm types, predict lower IQ in children with tuberous sclerosis complex eight years later.
Early seizure control appears critical for long-term intellectual outcomes, independent of socio-economic factors.
Key findings
01The mean estimated IQ at phase 2 in participants with TSC was 68.1, with 56.8% scoring under 70, indicating intellectual disability.
02A relative decrease in IQ over eight years was associated with younger age at seizure onset, history of status epilepticus, and increased severity of non-spasm seizures in the first two years of life.
03Structural equation modelling showed that the genetic mutation type influenced long-term IQ primarily through tuber load and early non-spasm seizure severity, rather than through spasms alone.
STILL TO COME
How it was doneWhat they foundWhat it means for PTsWhat it means for OTsWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
Brain imaging data were derived from routine clinical scans taken at different times and with different protocols, rather than a standardized research protocol. Different measures of intellectual ability were used across phases due to the wide age range, which may introduce measurement inconsistency. It is difficult to separate the cognitive effects of seizures from the effects of the brain tubers themselves, as tubers cause both. The study did not directly test the causal effect of seizure control interventions, but rather observed natural history associations.
Declared interests
Funding was provided by Autism Speaks, the Tuberous Sclerosis Association, the Baily Thomas Charitable Fund, and the Medical Research Council. No specific conflicts of interest regarding commercial entities were declared in the text.
The easy way to misread this
Do not assume that controlling epileptic spasms alone is sufficient to protect long-term IQ. The study found that non-spasm seizure severity in the first two years was a stronger predictor of intellectual decline than spasms in the long-term model.