NEFL and type 2 diabetes mellitus: The association of serum NFL levels with prevalent DSPN remained consistent when waist circumference and height were substituted with BMI (RR [95% CI] per 1-NPX increase 1.88 [1.47, 2.40]) and when the analyses were restricted to participants with type 2 diabetes (RR [95% CI] 1.96 [1.51, 2.54]).