Risk factors for intractable epilepsy at the time of initial diagnosis were determined in a case-control study at Yale University, New Haven, CT. Children with an average of one seizure or more per month over a 2-year period and refractory to at least 3 different AEDs were compared to controls who had been seizure-free for >2 years and had never had intractable epilepsy. Independent predictors of intractability were infantile spasms, early age of onset, remote symptomatic epilepsy, and status epilepticus. 
COMMENT. Age at onset was the predominant predictor of seizure intractability in this study, even after controlling for infantile spasms as a cause. Prognosis was progressively better with increasing age at onset during childhood and adolescence. For reports of neuropathology associated with intractable epilepsy, see Progress in Pediatric Neurology I, 1991, pp 131-138; and II, 1994, pp 129-141.