Early symptom progression rate is related to ALS outcome: a prospective population-based study

OBJECTIVE: To define the factors related to ALS outcome in a population-based, prospective survey. METHODS: The 221 patients (120 men and 101 women) listed in the Piemonte and Valle d'Aosta ALS Register between 1995 and 1996 were enrolled in the study. The patients were prospectively monitored with a standard evaluation form after diagnosis. RESULTS: Mean age at onset was 62.8 (SD = 11.2) years. According to El Escorial diagnostic criteria (EEDC), 112 patients had definite ALS, 85 probable ALS, 18 possible ALS, and six suspected ALS. The median survival time from symptom onset was 915 days (95% CI = 790 to 1065). The median survival time from diagnosis was 580 days (95% CI = 490 to 670). In univariate analysis, outcome was significantly related to age, onset site, EEDC classification, and symptom progression rate (i.e., the rate of decline of muscle strength and bulbar and respiratory function in the 6 months after diagnosis). In the Cox multivariate model, age, progression rate of respiratory, bulbar, and lower limb symptoms, EEDC classification, percutaneous endoscopic gastrostomy, and treatment with riluzole were significantly related to outcome. CONCLUSIONS: The rate of progression of symptoms in early ALS is predictive of disease outcome.