Compared with non-diabetics, a positive and significant association was found between higher NfL concentrations and cases with treated diabetes (b = 0.979, p < 0.05) but not, for cases with impaired fasting glucose levels (b = 0.950, p = 0.220) or untreated diabetes (b = 0.998, p = 0.624). This evidence concerns the gene NEFL and diabetes mellitus.