Epidemiological and clinical factors impact on the benefit of riluzole in the survival rates of patients with ALS.

Objective To investigate the impact of epidemiological and clinical factors on the benefit of riluzole in patients with amyotrophic lateral sclerosis (ALS). Methods The survival rate of 578 patients with ALS (1999-2011) was analyzed by descriptive statistics and Kaplan-Meier curves. Considering the median of the sample survival time (19 months), patients were divided in two groups: below (B19) and above the median (A19). Kaplan-Meier curves compared the survival rates of patients treated with riluzole and with patients who did not take the medication. Results Riluzole increased the survival rates of patients with lower limb onset who were diagnosed after the first appointment in B19. Patients with bulbar onset and diagnosed on the first, or after the first appointment showed higher survival rates in A19. Males lived longer than females in both groups. Conclusion Epidemiological and clinical factors influenced the benefit of riluzole in the survival rates of patients with ALS.