IL6 and amyotrophic lateral sclerosis: When the patients were separated into two groups according disease duration (ALS < 12 m or ALS ≥ 12 m), a positive correlation between IL-6 levels and disease progression was only verified in the ALS < 12 m group (r = 0.6605, p = 0.015) (Figure 3A) but not in the ALS ≥ 12 m group (r = 0.3510, p = 0.1291) (Figure 3B).