A previous cross-sectional case–control study found that higher concentrations of CSF-neurofilament light protein (NF-L), ratios of CSF-Aβ42/40 and CSF-Aβ42/38 were consistently associated with altered cognitive performance in euthymic patients with BD whereas CSF-p-tau and CSF-Aβ42 were not (Rolstad et al. 2015). Here, NEFL is linked to Behcet disease.