PROGNOSTIC INDICATORS OF SURVIVAL IN ALS

We analyzed data from the 245-patient placebo group of the ALS CNTF Tr eatment Study Group study, a large, prospective, multicenter study of recombinant human ciliary neurotrophic factor to determine prognostic factors for length of survival in ALS. Variables examined included bas eline demographic characteristics, indices of disease severity, pulmon ary function, and clinical laboratory tests. Shorter survival was asso ciated with greater age, lower percent-predicted forced vital capacity (FVC%), and lower serum chloride at study entry. A shorter interval f rom symptom onset to diagnosis of ALS and greater weight loss in the 2 months before study entry also predicted shortened survival times. Th e rate of muscle strength loss before study entry did not predict risk of mortality. Serum chloride, reflecting the degree of respiratory ac idosis, was identified for the first time as being correlated with pro gnosis in ALS. The relationship between a patient's FVC% and the proba bility of survival is described.