APOA1 and amyotrophic lateral sclerosis: Higher HDL (HR 0.78, 95% CI 0.64 to 0.96, p=0.017, adjusted p=0.054) and ApoA1 (HR 0.82, 95% CI 0.68 to 0.97, p=0.024, adjusted p=0.088) levels were associated with a lower risk of ALS.