THE NATURAL-HISTORY OF TYPE-I (SEVERE) SPINAL MUSCULAR-ATROPHY

The clinical features of 36 patients who satisfied the diagnostic crit eria for type I (severe) spinal muscular atrophy (Werdnig-Hoffmann dis ease) are reported. Survival data for both the whole cohort and for gr oups within the cohort subdivided on the age of onset are presented. T hese data suggest that the patients with onset at birth or within the first 2 months of life have a more uniformly poor prognosis with earli er death. This is of potential importance in any therapeutic trials in the future whose outcome may be based on length of survival.