From 1969 to 1990, 180 cases with West syndrome (WS) were admitted to
our hospital. We investigated the long-term outcome of 109 WS cases fo
llowed for over 3 years. Seizure remission and normal mentality were o
btained in 58.7% and 23.9%, respectively. Both seizure and mental prog
noses were significantly more favorable in the idiopathic group than i
n the symptomatic group. High-dose pyridoxal phosphate (PAL-P) therapy
was tried in 170 patients and was effective in 20 patients (11.8%). T
he long-term mental and seizure prognoses for the PAL-P-effective grou
p were favorable. Synthetic adrenocorticotropic hormone therapy (mean
maximum dose/day, 0.03 mg/kg; mean treatment duration, 26.7 days) was
tried in 114 patients and was effective in 101 (88.6%). Seizure remiss
ion and normal mentality were obtained in 55.8% and in 20.8% of patien
ts at the time of follow-up. The therapy duration was shorter, and tot
al dosage for suppression of seizures was lower than those reported in
previous studies. From 1987, high-dose valproate therapy was tried in
15 PAL-P-ineffective cases and was effective in 6 (40.0%), with the i
nitial effect maintained in all responsive cases at the time of follow
-up.