Probably, our result of a lower odds of association between C9orf72 expansion and hypertension may be due to the lack of this comorbidity among clinical features potentially related to the C9orf72-mediated pathology, although hypertension was proven associated to shorter survival time in ALS-C9Pos patients on univariate analysis. This evidence concerns the gene C9orf72 and amyotrophic lateral sclerosis.