APOA1 and amyotrophic lateral sclerosis: Incorporating all incident ALS cases, higher HDL (HR 0.84, 95% CI 0.73 to 0.96, p=0.010, adjusted p=0.035) and higher apoA1 (HR 0.83, 95% CI 0.72 to 0.94, p=0.005, adjusted p=0.031) were associated with a reduced risk of subsequent diagnosis of ALS.