NEFL and Alzheimer disease: One study reported no sex differences in the association between circadian rest-activity patterns and CSF measures of NfL, Aβ42, t-tau, or p-tau181 in mild-moderate AD patients [47], while another found a female vulnerability in the link between degradation in fractal motor activity regulation and PET-derived Aβ burden or CSF p-tau181/Aβ42 ratio in asymptomatic older individuals [48].